CSW 2023

Name	Affiliation, Country	Presentation Title
Takaaki Mano	NIMS, Japan	III-V heteroepitaxy on lattice mismatched (111)A-oriented substrates: application for the quantum light emitter and infrared detector
Yuji Zhao	Rice University, USA	Selective Area Regrowth and Doping for Vertical GaN Power Devices
Subhananda Chakrabarti	Indian Institute of Technology, India	Development of Indigenous Infrared Focal Plane Arrays at IIT Bombay
Kunal Mukherjee	Stanford University, USA	Engineering Reliability against Dislocations in InAs Quantum dot Lasers on Silicon

Name	Affiliation, Country	Presentation Title
Takuya Tsutsumi	NTT, Japan	Fabrication Process Technology of InP-based Tera-Hertz ICs for Beyond 5G / 6G Wireless Communication Networks
Austin Minnich	California Institute of Technology, USA	Cryogenic microwave noise characterization of GaN high electron mobility transistors

Name	Affiliation, Country	Presentation Title
Hyunseop Kim	Bristol University, UK	Study on Dynamic RON in AlGaN/GaN HEMTs Using Substate Bias Measurement
Gokhan Atmaca	Hongik University, Asia (Korea)	TCAD Modeling of β-Ga2O3 based High Power and High Frequency Devices
Andrei Kuznetsov	University of Oslo, Norway	Gallium oxide polymorph heterostructures: physics, fabrication, and potential applications
Xiaohang Li	KAUST, Saudi Arabia	Ultrawide bandgap CMOS and NMOS platform for heterogenous power integration
Jungwoo Oh	Yonsei University, Korea	Atomic Layer Deposition of BeO for Wide-Bandgap Semiconductor Heterostructures

Name	Affiliation, Country	Presentation Title
M. Ajmal Khan	FARMROID Co.Ltd. & CPR Riken, Japan	Advances and Challenges in Transparent AlGaN UVB LEDs
Frank Bertram	Otto-von-Guericke-University Magdeburg, Germany	AHighly Spatially Resolved STEM-CL Characterization of GaN-Based Power Devices
Jung-Hoon Song	Kongju National University, Korea	Strain evolution and ex-situ strain-profiling in GaN-related devices by surface-plasmon enhanced Raman spectroscopy
Chao Shen	Fudan University, China	GaN-based superluminescent diodes: advances and perspectives
Soon-Ku Hong	Chungnam National University, Korea	Structural Defects in Ultra-Wide Bandgap Homoepitaxial Ga2O3 Epilayers
Hee Jin Kim	Lumileds, USA	Recent Progress in Blue, Green and Red III-Nitride Epitaxy for Conventional and Micro LED Applications

Name	Affiliation, Country	Presentation Title
Donguk Nam	Nanyang Technological University, Singapore	On-chip light sources for integrated photonic quantum computing
Jae Woong Yoon	Hanyang University, Korea	Non-Hermitian and topological photonics with binary Hamiltonians
Young Joon Hong	Sejong University, Korea	Novel epitaxy of III-V for fabricating high-density hetero-integrated optoelectronics and flexible devices
Nobuhiko Nishiyama	Tokyo Institute of Technology, Japan	Membrane lasers and photonic integrated circuits on Si using room temperature direct bonding
Munho Kim	Nanyang Technological University, Singapore	Nanostructured Inorganic Wide Bandgap Semiconductors for Advanced Ultraviolet Photodetectors
Jooyoung Sung	DGIST, Korea	Spatial Dynamics of Charge Carriers in Perovskite Thin Films.

Name	Affiliation, Country	Presentation Title
Kyoung-Whan Kim	KIST, Korea	InGaN-based micro-LEDs fabricated by hydrogen passivation method
Gong Xiao	National University of Singapore, Singapore	Opportunities of Oxide Semiconductor-based Logic and Memories Devices
Jun Sung Kim	POSTECH, Korea	Novel magnetotransport properties of topological nodal-line fermions
Takashi Kimura	Kyushu University, Japan	Study of nano-scale heat transports using magneto-thermoelectric effects
Sunghun Lee	Sejong University, Korea	Ultrafast carrier dynamics and topological phases emerged in two dimensional materials heterostructures
Seung Chul Chae	Seoul National University, Korea	Neuromorphic device application of ferroelectric fluorite oxide thin film
Si-Young Choi	POSTECH, Korea	Atomic-scale understanding of metal-insulator transition in vanadium oxides
Yunseok Kim	Sungkyunkwan University, Korea	Highly enhanced ferroelectricity in HfO2-based ferroelectrics by defect engineering
Byoung Chul Choi	University of Alabama, USA	Synthetic Skyrmion-based Spin-Orbit Torque Nano-Oscillators

Name	Affiliation, Country	Presentation Title
Stefano Sanguinetti	Universita' degli Studi di Milano-Bicocca, Italy	Droplet Epitaxy Quantum Materials for Photonic and Energy Applications
Darius Kuciauskas	National Renewable Energy Laboratory, USA	Photoluminescence characterization of thin film solar cells to identify and reduce voltage losses
Moonkyu Jang	Hallym University, Korea	Impedance biosensors for cell growth and cell-drug reaction monitoring manufactured by semiconductor processes
Hyeong-Ryeol Park	UNIST, Korea	Low voltage terahertz tunneling plasmonics in metal-insulator-metal nanojunctions

Name	Affiliation, Country	Presentation Title
Yoon Seok Oh	UNIST, Korea	Boosting square tensile strain to promote functional 0-dimensional defect dipoles and reversible control of ternary polar states.
Hyun Sung Kum	Yonsei University, Korea	Remote epitaxy of freestanding single-crystalline complex-oxide membranes and applications
Bharat Jalan	University of Minnesota, USA	Perovskite Stannates as High Mobility Oxide Semiconductors
Elison Matioli	EPFL, Switzerland	Electrically accessible glass-like states in vanadium dioxide: a pathway for data storage and processing
Tianxiang Nan	Tsinghua University, China	Magnon Spin Transport in Spinel Ferrite Thin Films

Name	Affiliation, Country	Presentation Title
Se-Young Jeong	Pusan National University, Korea	A Growth of Cu(111) Thin Film with A Flat-Surface by Atomic-Sputtering Epitaxy and Colossal Oxidation Resistance
Jae-Won Jang	Dongguk University,Korea	Bandgap control of molybdenum disulfide thin-film transistor by tip-based nanolithography
Soaram Kim	Texas A&M University, USA	Quasi-Freestanding Epitaxial Graphene-based IoT Sensors for Remote

Name	Affiliation, Country	Presentation Title
Tae Hee Han	Hanyang Unversity, Korea	Mechanically resilient Perovskite Solar Cells based on Spontaneous Hybrid Cross-linked Network Formation
Hyunseong Kum	Yonsei Unversity, Korea	Remote epitaxy of freestanding single-crystalline complex-oxide membranes and applications
Joo Yeon Kim	ETRI, Korea	Metal Halide Perovskites as Color Conversion Layers in Display Applications
Namyoung Ahn	Los Alamos National Lab, USA	Development of Colloidal Quantum Dot Laser Diodes
Whi Dong Kim	KITECH, Korea	The study of carrier multiplication in quantum dot solids via detection of transient photocurrent
Han-Hee cho	UNIST, Korea	A Photoelectrochemical Tandem Cell Based on Organic Semiconductors for Overall Water Splitting
Hobeom Kim	GIST, Korea	Defect engineering of metal-halide perovskites for next-generation optoelectronic devices
Soyeon Kim	KIMS, Korea	Design and application of organic & inorganic materials for flexible optoelectronics

Name	Affiliation, Country	Presentation Title
Minjoo Lee	UIUC, USA	New directions in MBE growth for integrated photonics
Jonathan Klamkin	UCSB, USA	Direct Heteroepitaxy of Compound Semiconductors on CMOS-compatible Silicon for Photonics Applications
Kei May Lau	The Chinese University of Hongkong, HongKong	Monolithic lasers/photodetectors Grown on SOI for Silicon Photonics
Tatsuro Maeda	AIST,Japan	Monolithic 3D integrated devices by layer transfer technology of post-Si materials

Name	Affiliation, Country	Presentation Title
Zakaria Al Balushi	UC Berkeley, USA	Spatially Controlled Growth of 2D Materials
Hyungjin Kim	Yonsei University, Korea	Monolayer Semiconductors with High Luminescence Efficiency
Soo Min Kim	Sookmyung Woman University, Korea	Large-area uniform multilayer hexagonal boron nitride growth
Chao-Ching Cheng	Taiwan Semiconductor Manufacturing Company, Taiwan	Gate-All-Around Short-Channel Transistor of 2D Materials
Wei-Bo Gao	National University of Singapore, Singapore	Valleytronics by layer engineering
Houk Jang	Brookhaven National Laboratory, USA	In-sensor processing via integration of optoelectronic devices

Name	Affiliation, Country	Presentation Title
Byungjin Cho	Chungbuk National University, Korea	Strategy to implement the synaptic devices with heterosynaptic plasticity
Seyoung Kim	POSTECH, Korea	Resistive Memories and their Cross-point Arrays for AI Computation
Jiyong Woo	Kyungpook National University, Korea	Energy-efficient Neuromorphic Systems Driven by Emerging Device Technologies
Yonghun Kim	KIMS, Korea	All Solid-State Synapse Device Arrays using 2D channel/LiSiOx Electolyte for Next-Generation Neuromorphic Edge Computing

Name	Affiliation, Country	Presentation Title
Jieun Lee	Seoul National University, Korea	Electrical manipulation of quantum light sources in 2D materials
Dohun Kim	Seoul National University, Korea	Coherence of a singlet-triplet qubit driven by magnetic field gradient in isotopically purified silicon
Jehyung Kim	UNIST, Korea	Interfacing single-photon sources to real-world platforms
Donghun Lee	Korea University, Korea	Quantum sensing and imaging based on solid-state spin qubits in diamond
Akira Fujiwara	NTT Basic Research Laboratories, Japan	Electron manipulation in a silicon dynamic quantum dot
DongKeun Ki	The University of Hong Kong, Hong Kong	Quantum Coherence and Correlations in Multilayered Graphene Heterostructures
Sangwon Oh	KRISS, Korea	Diamond on the Brain: Quantum Diamond Magnetometers for Imaging Neuronal Connectivity
Myung-Joong Hwang	Duke Kunshan University, China	Frustration of quantum light and motion induced by qubits

Name	Affiliation, Country	Presentation Title
Jihye Kim	Issac Research, Korea	Atomic-Layer-Deposition for the Advanced Technology
Dong-Chul Shin	Samsung Advanced Institute of Technology Korea	Impact of lattice constant engineering for long wavelength InGaN μLEDs
Jarek Dolak	SVCS, Czech	Unknown Silicon Valley in the Heart of Europe
Sanghyun Jo	Samsung Advanced Institute of Technology, Korea	Negative Differential Capacitance in Ultrathin Ferroelectric Hafnia
Venugopal Govindarajulu	Yield Engineering Systems, USA	TGV Etching for Advanced Packaging - HVM Enablement

01. Epitaxy, Fabrication, and Related Technologies

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Takaaki Mano

NIMS, Japan

Biography

Takaaki mano is a principal researcher in National Institute for Materials Science (NIMS). He received Ph. D degrees in engineering (applied chemistry) from the University of Tokyo in 2000. He was a postdoctoral researcher in Eindhoven University of Technology in the Netherlands from 2000 to 2003. He joined NIMS in 2004 and has been mainly working on epitaxial growth of III-V materials for their optoelectronic device application.

Lecture Summary

III-V heteroepitaxy on lattice mismatched (111)A-oriented substrates: application for the quantum light emitter and infrared detector

InAs is a key semiconductor material for various photonic devices such as quantum light emitters using single QD at telecom wavelengths or infrared photodetectors at SWIR region. We have recently developed heteroepitaxy of InAs on lattice mismatched InP or GaAs (111)A substrates toward the advanced photonic devices. On these lattice mismatched (111)A substrates, lattice-relaxed InAs are formed due to the formation of a misfit dislocation network at the interface, which is in stark contrast to the Stranski-Krastanow growth on (100) substrates. In order to form highly symmetric InAs QDs on InP(111)A for entangled photon emitters, we have applied droplet epitaxy and successfully observed their quantum light emission. In addition to the formation of QDs without dislocation, we have also focused on the lattice-relaxed bulk InAs grown on GaAs(111)A with high density dislocations at the interface. By using the characteristic properties of this InAs/GaAs(111)A system, we demonstrated low-dark current operation of the infrared photodetectors. In this talk, I will present the growth of InAs on the lattice mismatched (111)A substrates and discuss their potential for their application. This work was supported by Innovative Science and Technology Initiative for Security, Grant Number JPJ004596, ATLA, Japan.

01. Epitaxy, Fabrication, and Related Technologies

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Yuji Zhao

Rice University, USA

Biography

Dr. Yuji Zhao is an Associate Professor at Rice University and the director of the Rice WIDE Lab. He received the Ph.D. degree from University of California Santa Barbara (UCSB) under the guidance of Nobel Laureate Professor Shuji Nakamura. Dr. Zhao's research interests are in the area of wide and ultrawide bandgap semiconductor devices for energy efficiency, power and RF electronics, and quantum photonics applications. He has published 4 book chapters, over 100 journal papers, over 100 conference proceedings and presentations, and over 20 patents. His awards include the 2019 Presidential Early Career PECASE Award from the White House, which is the highest honor given by the US government to early-career scientists and engineers. He is also a recipient of TMS Frontiers of Materials Award, MIT TR35 Award, DTRA Young Investigator Award, NASA Early Career Faculty Award, and several best paper awards. He is a committee member of IEEE EDS Optoelectronic Devices Committee. He also serves on the conference committee of Device Research Conference (DRC), CLEO, and ECS Meeting.

Lecture Summary

Selective Area Regrowth and Doping for Vertical GaN Power Devices

Vertical GaN power devices are key enabler for the next-generation power electronic devices with higher efficiency, higher power density and smaller form factor. One of the most critical building blocks for vertical GaN power devices is the laterally patterned GaN p-n junctions, which are the basis for many advanced GaN power devices and edge terminations, such as vertical junction field-effect transistors (VJFETs), junction termination extension (JTE), and junction barrier Schottky (JBS) or merged pn/Schottky (MPS) diodes. Due to the lack of effective ion implantation process, selective area regrowth and doping using MOCVD is widely regarded as the promising method to realize laterally patterned GaN p-n junctions. However, regrown GaN p-n junctions often suffer from high leakage currents and low breakdown voltages, posing significant scientific challenges. In this talk, recent progress on selective area regrowth and doping for vertical GaN power devices is reviewed. Comprehensive materials characterization techniques were utilized to analyze the regrown structures, including scanning electron microscopy, transmission electron microscopy, atom probe tomography, scanning probe microscopy, and secondary-ion mass spectrometry. Cathodoluminescence, secondary electrons in scanning electron microscopy, and atom probe tomography were used to achieve lateral and vertical dopant profiling at a sub-micron scale. Novel etching techniques, such as low-power dry etching, atomic layer etching, and in situ etching, were also developed to improve the regrowth interface. These results represent important progress towards the realization of GaN vertical power transistors.

01. Epitaxy, Fabrication, and Related Technologies

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Subhananda Chakrabarti

Indian Institute of Technology, India

Biography

Subhananda Chakrabarti received the M.Sc. and Ph.D. degrees in Electronic Science from the Department of Electronic Science, University of Calcutta, Kolkata, India in 1993 and 2000 respectively. He was a Senior Research Fellow with the University of Michigan, Ann Arbor, MI, USA, from 2001 to 2005, a Senior Researcher with Dublin City University, Dublin City, Ireland, from 2005 to 2006, and a Senior Researcher (RA2) with the University of Glasgow, Glasgow, U.K., from 2006 to 2007. He joined the Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai, India, in 2007. Presently, he is a Professor in the same department. He has extensively researched molecular beam epitaxial growth, and characterization and fabrication of semiconductor optoelectronic materials and devices, such as quantum dot laser, inter-subband detectors, and vertical-cavity surface and emitting lasers. He has authored or coauthored more than 500 papers in international journals and conferences. He has guided/graduated 26 PhDs till date and 6 more PhD students are still working under his supervision. He demonstrated a completely indigenous infrared focal plane arrays, which could image human signature. Dr. Chakrabarti is a reviewer of various international journals of repute such as Applied Physics Letters, Journal of Applied Physics, IEEE PHOTONICS TECHNOLOGY LETTERS, the IEEE JOURNAL OF QUANTUM ELECTRONICS etc. He has also coauthored a couple of book chapters on inter-subband quantum dot detectors and four monographs of his have been published by SPRINGER. He is the recipient of the MRSI medal (2016), NASI-Reliance Industries Platinum Jubilee Award for Application Oriented Innovations in Physical Sciences (2016), Abdul Kalam Technology Innovation National Fellowship, INAE (2020), Fellow IETE, etc. He is a Fellow of SPIE, USA, Fellow of IET, UK, Fellow of IOP UK, Fellow of INAE India, Senior Member of IEEE (USA) and Member of OSA, USA.

Lecture Summary

Development of Indigenous Infrared Focal Plane Arrays at IIT Bombay

Self-assembled In(Ga)As/GaAs quantum dot (QD) heterostructures grown by Stranski-Krastanov (SK) mode have been extensively used in various optoelectronic applications such as detectors, lasers, VCSELs etc. The three dimensional carrier confinements along with phonon bottleneck in these QD based devices deliver better performance over bulk and quantum-well counterparts. In order to enhance the performance characteristics of future QD heterostructures, a detailed investigation of (i) the impact of varying strain, (ii) coupling of homogenous and heterogenous QD families and (iii) the effect of various ex-situ treatments (such as ion implantation and rapid thermal annealing) on the optical, structural and device characteristics of In(Ga)As/GaAs Quantum Dot based Heterostructures were investigated. The impact of some of the techniques on the performance of QD based infrared focal plane arrays would also be presented. DST, SERB, IITBNF, INAE are acknowledged.

01. Epitaxy, Fabrication, and Related Technologies

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Kunal Mukherjee

Stanford University, USA

Biography

A reliable III-V semiconductor laser monolithically integrated on silicon is key to cost-effective and scalable advanced photonic integrated circuits. The reliability of such a direct epitaxially grown device has traditionally been held back by very rapid degradation due to a large density of vertical threading dislocations (TDs), even for the more defect tolerant InAs quantum dots. We show that the root cause for rapid degradation in these devices are actually horizontal misfit dislocations (MDs) that form after growth as the sample cools due to a combination of: (1) residual tensile strain in the III-V layers due to thermal expansion mismatch with silicon and (2) pinning of the threading dislocation segment by the indium-containing regions during cool down. Understanding this leads us to use a new type of indium-based trapping-layer filter using random alloy hardening to displace the location of these MDs away from the active region and improving the laser lifetime by a factor of 100× at elevated temperatures of 80 °C to record values. Even so, state-of-the-art device lifetimes still fall somewhat short of requirements for more widespread adoption as the lasers still exhibit a much more gradual degradation with aging. We demonstrate that this gradual degradation is a result of the generation of point defect populations during aging, which, over time, coalesce into dislocation microloops which we characterize using detailed electron microscopy. In summary, our work identifies both rapid and gradual degradation mechanisms and points the way to engineering a truly reliable monolithically integrated laser on silicon.

Lecture Summary

Engineering Reliability against Dislocations in InAs Quantum dot Lasers on Silicon

Kunal Mukherjee is an assistant professor in the Department of Materials Science and Engineering at Stanford University. His research interests are in semiconductor thin film synthesis and defect science. Kunal received his B.Eng. in Electrical Engineering from Nanyang Technological University in Singapore and his Ph.D. in Materials science from MIT. Before joining Stanford, he has been an assistant professor in the Materials department at UC Santa Barbara (2016-2020), held postdoctoral appointments at IBM TJ Watson Research Center and MIT, and worked as a transceiver engineer at Finisar Corporation.

03. High Power and High Frequency Electron Devices

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Jungwoo Oh

Yonsei University, Korea

Biography

Dr. Jungwoo Oh received his Ph.D. in Engineering from the University of Texas at Austin 2004. He conducted research on Ge photodiodes and Si photonics in Dr Joe C. Campbell's group at the Microelectronic Research Center. He joined the SEMATECH CMOS Extension team and developed alternative channel materials using Ge/III-V semiconductors with an international consortium. Dr. Oh was appointed in 2012 as a tenure track faculty at the School of Integrated Technology, College of Engineering Yonsei University, which was established for convergence education and research. His research team developed "Chemical Imprinting" technology using metal-assisted chemical etching, and this technology was well evaluated as alternative lithography and published the results in ACS NANO and US patents. In addition, his team developed “Atomic layer deposition of BeO” and heterostructures of wide-band gap semiconductors and published papers in top tier journals. The high thermal conductivity and unique physical properties of crystalline BeO show the potential to significantly improve the performance of power semiconductors and Si 3D integrated circuits. Dr. Jungwoo Oh received B.S. and M.S. degrees from Yonsei University and POSTECH, respectively.

Lecture Summary

Atomic Layer Deposition of BeO for Wide-Bandgap Semiconductor Heterostructures

BeO (Beryllium Oxide) is a material that has a higher thermal conductivity than most insulators and metals. Among metals, gold, silver and copper have higher thermal conductivity than BeO. Among insulators, a diamond is the only material that has a higher thermal conductivity than BeO. In addition, BeO has a high dielectric strength and good electrical insulation properties. These characteristics make BeO an attractive dielectric for use in high-temperature and high-power electronic applications and substrates of integrated circuits to dissipate large amounts of heat. Historically, BeO was synthesized by powder sintering method and was mostly used in a mechanical structure requiring high heat conduction. The number of cases used for nano-scale front-end electronic devices was very small. We developed atomic layer deposition (ALD) of crystalline BeO thin films on wide bandgap semiconductors (GaN, SiC, Ga2O3). This talk presents the electrical and physical properties of ALD BeO deposited on wide-bandgap semiconductors. Our team's results on epitaxial crystalline characteristics, conduction band-offsets measurements, and polarization characteristics demonstrated in heterostructures are comprehensively presented. The precise control of the film thickness and the ability to deposit BeO with a high degree of conformality that ALD offers, can help to improve the performance of power transistors.

03. High Power and High Frequency Electron Devices

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Andrei Kuznetsov

University of Oslo, Norway

Biography

Andrej Kuznetsov was awarded with his Ph.D. degree in physics from the Russian Academy of Sciences in 1992 and accomplished his habilitation in solid state electronics in 2000 at the Royal Institute of Technology in Sweden. In 2001 he joined the Department of Physics at the University of Oslo in Norway as an associate professor and was subsequently promoted to the full professor rank in 2003. From 2018 he acts as the Chair of the Centre of Excellence: Light and Electricity from Novel Semiconductors (LENS)-as a part of the Centre for Materials Science and Nanotechnology at the University of Oslo. His focus is to understand novel semiconductors, searching for new fundamental phenomena and enabling new device functionalities. He taught at different levels, at present gives an introductory condensed matter physics course at the BSc level, as well as supervised a big number of students at the MSc and PhD levels. He managed research funds in Russia, Sweden, Norway, as well as EU grants.

Lecture Summary

Gallium oxide polymorph heterostructures: physics, fabrication, and potential applications

There are no perfectly regular organized systems in nature. In crystals, there are always defects occurring in lattices, e.g. in form of vacancies, helping to decrease the Gibbs energy due to increasing entropy. Nevertheless, on many occasions, structural defects bare a negative connotation, provoking efforts to reduce their contents. On the other hand, many unique material properties may become possible only with defects in materials. In this talk, I will review a recent observation of the disorder-induced ordering in gallium oxide controlled by the accumulation of intrinsic defects (PRL 128, 15704 (2022). Indeed, polymorphs are common in nature and can be stabilized by applying external pressure in materials. The pressure/strain can also be induced by the gradually accumulated radiation disorder. However, in semiconductors, the radiation disorder accumulation typically results in the amorphization instead of engaging polymorphism. By studying these phenomena in gallium oxide, we found that the amorphization may be prominently suppressed by the formation of a new polymorph. Utilizing this discovery, we fabricated polymorph heterostructures having unprecedently sharp interfaces, potentially applicable in devices.

03. High Power and High Frequency Electron Devices

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Xiaohang Li

KAUST, Saudi Arabia

Biography

Xiaohang obtained Ph.D. in Electrical Engineering from Georgia Institute of Technology where he received the Institute’s highest graduate student honor, the Edison Prize. He is an Associate Professor and leads the Semiconductor Initiative at KAUST. His research focuses on ultrawide bandgap (UWBG) semiconductors for next-generation electronics and photonics. His team has made notable inventions and contributions in the field, including the first UWBG CMOS. He has authored >130 journal and >180 conference publications along with five book chapters and editorials. He has >14 issued and 28 pending patents. He has given >110 invited and plenary talks and seminars. His Polarization Toolbox software is used by >70 institutions and companies. He is the recipient of several prestigious awards including the biennial Harold M. Manasevit Young Investigator Award from the American Association for Crystal Growth, the SPIE D. J. Lovell Scholarship, the IEEE Photonics Graduate Student Fellowship, the Georgia Tech 40 under 40 Alumni Award. He has served as an Associate Editor of Photonics Research and as a committee member of several leading conferences including IWN, EMC, CSW, IC-MOVPE. His students have received competitive student awards from organizations, conferences, and industry such as SPIE, MRS, IWN, Fulbright Program, Oxford Instruments. Outside of work, he is fond of hiking and traveling.

Lecture Summary

Ultrawide bandgap CMOS and NMOS platform for heterogenous power integration

Saravanan Yuvaraja, Vishal Khandelwal, Dhanu Chettri, Yi Lu, Xiao Tang, Xiaohang Li

Advanced Semiconductor Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia

Compared to silicon, ultrawide bandgap NMOS and CMOS integrated circuits (ICs) could offer superior temperature and radiation tolerance and excellent processing compatibility with (ultra)wide bandgap devices. This is crucial for future generations of “intrawafer” heterogeneous integration with power devices. Because it would allow the whole power system to have miniaturized footprint, less cooling/heating, and greatly enhanced energy efficiency. In this talk, we will discuss our latest works of demonstrating the ultrawide bandgap CMOS for heterogeneous integration along with our works of UWBG materials, physics, and devices.

03. High Power and High Frequency Electron Devices

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Jang-kwon Lim

RISE, Sweden

Biography

Jang-Kwon Lim received the M.E. and the Ph.D. degrees in Electrical Engineering from the Korea University Seoul, Korea, in 2005 and from the Royal Institute of Technology (KTH), Stockholm, Sweden in 2015, respectively. From 2004 to 2005, he was a Research Fellow at Korea Electronics Technology Institute (KETI), Seongnam, Korea. From 2005 to 2007, he was an Associate Research Engineer with LG materials/Components R&D center, Ansan, Korea. From 2008 to 2018, he was a Research Scientist at RISE Acreo AB, Kista, Sweden, where he was involved in several projects related to the research on SiC power devices and power electronics. From 2018 to 2020, he was a SiC Power Devices and Apps Engineer in ON Semiconductor Corporate R&D, where he had the responsibilities on the high voltage dynamic testings and the improvement on the switching performance for SiC MOSFETs. From 2020, he was back to RISE AB as a Senior Research Scientist and currently focusing on Wide bandgap semiconductor devices and power electronics applications. His expertise is device simulations, electrical characterizations (static, dynamic, and reliability testings), and apps testing. He is currently IEEE senior member.

Lecture Summary

WBG Power Device Modelling, Characterizations, and Reliability Studies

Jang-Kwon Lim
Division of Digital Systems, Department of Smart Hardware, Unit of System Integration,
Research Institutes of Sweden (RISE) AB, Electrum 236, 164 25, Kista, Sweden
Email: Jang-Kwon.Lim@ri.se

The power electronics and wide bandgap (WBG) power semiconductor devices are key enabling technologies for the sustainable future. They are important tools to be employed to master growing global demand for electric energy and the threat of climate change. Introduction of WBG power devices in power electronics systems used in generation, distribution and consumption of electricity results in significant improvement of system efficiency and spectacular energy savings. In order to accelerate adoption of the WBG devices it is necessary to prove and quantify advantages for different applications and ascertain reliability and robustness of commercial devices.
RISE AB has over 20 years of experience and competence in WBG technology and device development based on simulations and performance analysis. In this paper, author presents selected examples from the research and industrial development projects in the areas of device design, characterization and reliability. Specific examples of device studies are modelling and characterization of diodes and MOSFETs for system analysis, short circuit and cosmic radiation robustness, oxide reliability and threshold voltage stability and power cycling capability.

04. Wide Bandgap Semiconductors

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M. Ajmal Khan

FARMROID Co.Ltd. & CPR Riken, Japan

Biography

Dr. M. Ajmal Khan (Wazir) was born in Wana (South Waziristan), Pakistan. He received his M.Sc and M.Phil degrees in Applied Physics from Quaid-i-Azam University, Islamabad, Pakistan, in 1998 and 2001, respectively. Later, he received his PhD degree in applied physics from Graduate School of Pure and Applied Sciences, University of Tsukuba, Japan in 2013. In 2012, during his PhD work, he has discovered the thin film of boron (B) doped p-type BaSi2 layer "p+" along with his PhD supervisor Prof. Takashi Suemasu (Appl. Phys. Lett. 104, 252104 (2014)). After his discovery the efficiency of the solar cell was enhanced from 1.4% to 10%. Later he joined the team of FUTURE PV-Innovation, Japan Science and Technology Agency, Fukushima Renewable Energy AIST Institute (FREA), Koriyama in 2014 and worked on Si NWs, c-SiGe and a-Si/c-Si heterojunction solar cells. In 2017, he moved to Prof. Hideki Hirayama Lab at RAP Riken and later in 2020 moved to RIKEN Cluster for Pioneering Research as a research scientist. Since then, he has been doing research on the epitaxial growth, characterization, and device applications of group III-nitride semiconductor-based UV LEDs and UV Laser Diodes. He has developed an AlGaN UVB LED with a world record efficiency of 9.6% with a light power of 40 mW on the wafer (Sci Rep 12, 2591 (2022)). In 2021, he moved to Farmroid Co., Ltd as a senior research scientist and to work on the R&D project of Far-UVC LED for SARS-CoV-2 inactivation. He bears various roles and responsibilities, such as being a visiting Scientist at RIKEN, a renowned member of the Japan Society of Applied Physics (JSAP), and guest editor of the MDPI journal of “Crystals”. He delivered more than 100 talks including keynote and invited talks in the international conferences. Also contributed more than 120 research papers.

Lecture Summary

Advances and Challenges in Transparent AlGaN UVB LEDs

Eco-friendly and non-toxic semiconducting aluminum gallium nitride (AlGaN) materials for the development of ultraviolet - B (UVB) light sources are strongly needed for medical, agricultural and environmental applications [1]. When producing AlGaN-based epitaxial-structures on c-sapphire for UVB emitters, then threading dislocations (TDs) arise from the large lattice-mismatch of 13.3% between c-sapphire and the AlN epitaxial layer, as well as the possibility of kinetic separation using an Al-contents of 40-50 percent. We found that the nature of relaxation in the n-AlGaN electron-source layer (ESL) strongly influences piezoelectricity, extended defects, point defects, aluminium-alloy fluctuations and non-radiative recombination centres in the in the multi-quantum wells (MQWs), which can ultimately degrade the internal-quantum efficiency (IQE). We have found at Riken, together with Yamaguchi University, when we insert a 3.4 μm-thick n-AlGaN buffer layer underneath an n-AlGaN ESL, the relaxation ratio of n-AlGaN ESL reached to 49%, and the density of TDs are reduced to 7 × 108 cm-2 (IQE ~ 54%) [1]. Furthermore, when Al-graded p-type multi-quantum-barrier electron-blocking-layer (Al-grad p-MQB EBL) and Al-graded p-AlGaN hole-source layer (HSL) for the generation and injection of 3D holes in the active region was used then the record efficiency of 9.6% and light output power of 40 mW, on bare-wafer under continuous-wave operation at RT were achieved [1]. It is of no surprise that these devices are overshadowed by their bl

05. Photonic and Optoelectronic Devices and Related Technologies

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Nobuhiko Nishiyama

Tokyo Institute of Technology, Japan

Biography

Nobuhiko Nishiyama received his B.E., M.E., and Ph.D. degrees from the Tokyo Institute of Technology, Japan, in 1997, 1999, and 2001, respectively. During his Ph.D. work, he demonstrated single-mode 0.98- and 1.1-µm VCSEL arrays with stable polarization using misoriented substrates for high-speed optical networks and MOCVD-grown GaInNAs VCSELs. In 2001, he joined Corning, Inc., New York, where he worked with the Semiconductor Technology Research Group on several subjects, including short-wavelength lasers, 1060-nm DFB/DBR lasers, and long-wavelength InP-based VCSELs. In 2006, he was appointed as an Associate Professor with the Tokyo Institute of Technology, and since 2020, he has been a Professor there. His current main interests include transistor lasers, silicon photonics, III-V silicon hybrid optical devices, and terahertz-optical signal conversions involving optics-electronics-radio integration circuits.
Dr. Nishiyama is a member of the Japan Society of Applied Physics (JSAP), IEEE, and IEICE. He has served and is serving in several society roles, such as the IEEE Photonics Society Board of Governors and JSAP Director. He was the recipient of the Excellent Paper Award from the Institute of Electronics, Information and Communication Engineers (IEICE) of Japan in 2001, the Young Scientists’ Prize of the Commendation for Science and Technology from the Minister of Education, Culture, Sports, Science and Technology in 2009, and the Ichimura Prize in Science for Distinguished Achievement in 2016.

Lecture Summary

Membrane lasers and photonic integrated circuits on Si using room temperature direct bonding

Membrane lasers and photonic integrated circuits (PICs) are thin-film semiconductor devices with desirable features such as compactness and low power consumption. This talk will provide a brief overview of their fabrication process, characteristics, and applications. In order to integrate InP-based membrane layers on Si, a few-nm amorphous-Si was introduced to modify the bonding interface to Si/Si. This was followed by a room temperature surface activated bonding process, which produced a high yield hybrid bonded wafer. The membrane laser offers over three times higher optical confinement to the active layers than the conventional double hetero laser structure. Additionally, introducing a surface grating enables high coupling coefficients, as distributed feedback or distributed reflector lasers. These devices are highly efficient, with a threshold of less than 0.2 mA and modulation exceeding 20 Gbps. Membrane PICs can operate at temperatures over 100°C, making them versatile and suitable for a variety of applications.

06. Semiconductor Physics, Spintronics, Ferroelectronics, and Novel Device Concepts

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Kyoung-Whan Kim

KIST, Korea

Biography

Academic Experience

11/2018 - Present Senior Research Scientist Center for Spintronics, KIST, Korea
09/2016 - 10/2018 Postdoctoral Researcher Institute of Physics, JGU Mainz, Germany
09/2016 - 09/2016 Guest Researcher Institute of Physics, JGU Mainz, Germany
03/2015 - 08/2016 Postdoctoral Researcher Center for Nanoscale Science and Technology, NIST, USA
02/2015 - 08/2016 Postdoctoral Researcher Institute for Research in Electronics and Applied Physics, UMD, USA
08/2014 - 02/2015 Guest Researcher Center for Nanoscale Science and Technology, NIST, USA
02/2013 - 02/2015 Postdoctoral Researcher Basic Science Research Institute, POSTECH, Korea
03/2009 - 02/2013 Research Assistant Department of Physics, POSTECH, Korea
03/2009 - 06/2010 Teaching Assistant Department of Physics, POSTECH, Korea
08/2008 - 12/2008 Grading Assistant Department of Physics, POSTECH, Koreav

Research Interests

Graphics Illustrator, Mathematica, Powerpoint, Photoshop, Blender, Inkscape
(*) Certificate in Craftsman Computer Graphics Operation (July 1, 2002) by Ministry of Trade, Industry and Energy, Korean Government
Documentation LaTeX, Word, Mathematica, Excel, HTML
Programming Mathematica, TeX, C, C++, Python, Java, Fortran, Matlab, Basic, Assembly
Presentation Powerpoint, LaTeX
Language Korean (native), English, Japanese (basic)

Lecture Summary

Orbital Angular Momentum and Orbital Angular Position Dynamics in Solids

Kyoung-Whan Kim
Center for Spintronics, Korea Institute of Science and Technology

Roles of orbital angular momentum of electrons in solids have been ignored for a long time because of the orbital quenching. However, recent theoretical and experimental reports imply that orbital angular momentum is not quenched in nonequilibrium. Furthermore, it is claimed that the orbital degree of freedom is crucial for anomalous spin transport phenomena such as spin Hall effect. Therefore, understanding the dynamics of orbital angular momentum has become important in the aspect of both fundamental science and spintronic applications. However, it has been believed that the dynamics of orbital angular momentum and that of spin angular momentum are qualitatively similar, so it is difficult to separate those contributions experimentally.
In this work, we point out a fundamental difference between the orbital and spin angular momenta by revealing a hidden degree of freedom of the orbital angular momentum, which we call the orbital angular position. It mediates the oscillation of the orbital angular momentum even without breaking time-reversal or spatial-inversion symmetry, which is impossible for spin. Our quantum Boltzmann approach indicates that considering the orbital angular position is essential for theoretical description of orbital transport. Also, we propose several experimental methods to measure the distinct dynamics of orbital angular momentum.

06. Semiconductor Physics, Spintronics, Ferroelectronics, and Novel Device Concepts

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Takashi Kimura

Kyushu University, Japan

Biography

TBA

Lecture Summary

Study of nano-scale heat transports using magneto-thermoelectric effects

Recent development of nano-fabrication techniques enables to realize functional electronic devices with the lateral dimension down to nano-meter scale. In the operation of such nano sized devices, understanding and controlling the heat transfer is an important issue because a small cross section produces a significant Joule heating effect. Since the characteristic lengths such as the mean free path and phase coherent length are comparable to the device dimension, the heat transport in nanostructured systems may be different from the bulk state and its combination. On the other hand, In the field of spintronics, in addition to the intriguing spin-dependent transports, various conversion phenomena between spin and heat have been reported recently, and a new research field has been emerged named as spincaloritronics. Therefore, it is essential to deepen understanding the heat transfer in nanospintronic devices for manipulating the heat as well as for developing spincaloritronics. In this presentation, we introduce heat-transport phenomena in various ferromagnetic/nonmagnetic metal hybrid structures by using unique magneto-thermoelectric effects.
First, the spatial temperature distribution in a laterally configured nanostructure based on GMR nanowire has been investigated.[1] A large thermal spin valve effect enables us to distinguish the flowing direction of the heat in the GMR nanowire. We find that the heat flow from the substrate is significant. Second, a temperature distribution in a ferromagnetic nanowire has been investigate by using various magneto-thermoelectric effects.[2] The combination between the anisotropic magento-Seebeck effect and anomalous Nernst effect enables us to understand a three-dimension temperature gradient in a ferromagnetic nanowire precisely. We find that the transverse heat flow is a significant contribution on the field dependence of the Seebeck voltage. Finally, temperature dependence of the thermal spin valve effect and anisotropic magneto-Seebeck effect have been investigated. We find that the signs of the voltage changes were reversed at specific temperatures. Possible mechanism has been discussed in order to explain the unique signatures.
Thus, by the optimization of the device structures, enhanced thermal spin valve version of the GMR effect, anisotropic magneto-Seebeck effect and anomalous Nernst effect have been obtained. Multiple ways in which heat interacts with spin and the interplay of such effects enablesus to evaluate the heat distribution. These demonstration paves the way for the precise analysis of the heat flow in nano-structured electronic devices.

07. Nanostructure and Nano Characterization

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Moonkyu Jang

Hallym University, Korea

Biography

Research

Nano Transistor, Schottky transistor, Quantum devices, Graphene devices, Thermoelectric devices, Biosensor

Career

1997. 3 ~ 2001. 10: Principal Research Staff, Hynix
2001. 10 ~ 2014. 8: Electronics and Telecommunication Research Institute
2010. 3 ~ 2014. 8: Professor of University of Science and Technology
2014. 9 ~ current: Professor of Hallym university

Committee

Korean Physical Society & Korean Vacuum Society member
2009. 6 ~ 2012. 7: Editor of Journal of Korean Physical Society
2010. 1 ~ current: NanoKorea program committee member
2010. 9 ~ current: Editor of Journal of Nanoscience Letters (USA)
2013 ISPSA Energy session organizer
2013~ current: NanoKorea nanoelectronics session organizer

Awards

Best paper awards in Korean Conference on Semiconductors (2004, 2005).
Best paper awards (2005) and best research staff awards in ETRI (2006)
Best lecturer awards in University of Science and Technology (2012).
Best project quality awards in ETRI (2013)
Semiconductor awards in Korean Physical Society (2017).
Award from Minister, Ministry of Science and ICT (2018)

Lecture Summary

Impedance biosensors for cell growth and cell-drug reaction monitoring manufactured by semiconductor processes

Electrical Cell-substrate Impedance System and Electrical Impedance Spectroscopy are the widely used methods in the field of biosensors for the monitoring of the status of cell. On the contrary, the usually used biosensors are bulky and hard to monitor in real time.
In this work, temperature/impedance integrated sensors are manufactured using semiconductor process for the simultaneous monitoring of the temperature and impedance variations during the cell-drug reactions. The developed platinum thin film temperature sensor showed the inaccuracy less than ±0.05 ℃ and the MEMS process is adopted to enhance the temperature sensitivity. HeLa cancer cells and NIH 3T3 cells are grown on the biosensors and the drug reactions are monitored as a function of time and frequency. The impedance rapidly increase at the early stage and gradually decreased with time as a results of cell-drug reactions. From the impedance measurements, we evaluated the single cell capacitance of NIH 3T3 cells with various frequencies. Also, the temperature variations are monitored during the Hela cancer cell-drug reactions. The results are compared with the results by biological cell viability test on the conventional culture plates. The time and frequency dependent impedance signals are analysed in detail with the comparison between biological results.

08. Oxide Semiconductors

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Yoon Seok Oh

UNIST, Korea

Biography

Research Focus

Magnetic/Electric/Electronic phase transition in strongly correlated condensed matter system
Quantitative determination of physical property under cryogenic temperature, high magnetic field, and high hydrostatic/uniaxial pressure
Single crystal synthesis of the strongly correlated electron system, and development of new material system.

Professional Experience

Associate Professor, Department of Physics, UNIST, March 2021 - present
Assistant Professor, Department of Physics, UNIST, August 2014 - February 2021
Postdoctoral Research Associates, Department of Physics & Astronomy, Rutgers University, USA, December 2011 - July 2014
Postdoctoral Researcher, Department of Physics & Astronomy, Rutgers University, USA, December 2010 - December 2011
Postdoctoral Researcher, Department of Physics & Astronomy, Seoul National University, USA, March 2010 - November 2010

Education

Doctor of Philosophy in Physics, February 2010, Seoul National University, Department of Physics & Astronomy (Supervisor: Professor Kee Hoon Kim)
Master of Science in Physics, February 2006, Seoul National University, Department of Physics & Astronomy.
Undergraduate study at Seoul National University, March 1997 - February 2004. (Department of Physics)

Publications, selected

[2022] Reversibly controlled ternary polar states and ferroelectric bias promoted by boosting square-tensile-strain, Jun Han Lee et al. and Yoon Seok Oh*, Advanced Materials 34, 2205825 (2022). [IF: 32.086, Citation: 2]
[2015] Experimental demonstration of hybrid improper ferroelectricity and the presence of abundant charged walls in (Ca,Sr)3Ti2O7 crystals, Yoon Seok Oh* et al., Nature Materials 14, 407 (2015). [IF: 46.863, Citation 370]
[2014] Non-hysteretic colossal magnetoelectricity in a collinear antiferromagnet, Yoon Seok Oh* et al., Nature Comm. 5, 3201 (2014). [IF: 14.919, Citation: 116]
[2013] Anionic Depolymerization Transition in IrTe2, Yoon Seok Oh* et al., Phys. Rev. Lett. 110, 127209 (2013). [IF: 9.161, Citation: 101]
[2010] Quantitative determination of anisotropic magnetoelectric coupling in BiFeO3-CoFe2O4 nanostructures, Yoon Seok Oh* et al., Appl. Phys. Lett. 97, 052902 (2010). [IF: 3.791, Citation: 73]
[2007] Interplay between Fermi Surface Topology and Ordering in URu2Si2 Revealed through Abrupt Hall Coefficient Changes in Strong Magnetic Fields, Yoon Seok Oh* et al., Phys. Rev. Lett. 98, 016401 (2007). [IF: 9.161, Citation: 73]

Lecture Summary

Boosting square tensile strain to promote functional 0-dimensional defect dipoles and reversible control of ternary polar states.

The manipulation of ground states in complex oxides using heterostructures offers a breakthrough in terms of creating/enhancing advanced functionalities as well as understanding their fundamental nature. For epitaxial heterostructures and free-standing membranes, feasible materials and physical properties strongly depend on the symmetry and misfit lattice constant of substrates because the substrate stipulates a fundamental platform to build up thin films. Prevalent perovskite oxide substrates, such as cubic SrTiO3 and orthorhombic R(Al/Sc/Lu)O3 (R=rare earth), have been prominently employed to develop advanced functional heterostructures. However, their congenital symmetry and limited lattice constants circumscribe advances in the functionality and material diversity of the heterostructures. Here, we introduce a new substrate of cubic perovskite BaZrO3 to boost square tensile strain and demonstrate promoted 4-variants in-plane ferroelectricity on BaZrO3 substrates. The lattice constant of BaZrO3 is +8.7 % larger than that of SrTiO3, which enables the application of a very large tensile strength, and the cubic symmetry promotes a 4-fold symmetric square lattice on the (001) surface, in contrast to the orthorhombic substrates. The square tensile strain is found to coin built-in defect dipoles as well as in-plane ferroelectrics with 4-variants polar domains, the cooperation of which gives rise to switchable ternary polar sates characterized by a switchable bias field and in the ferroelectric hysteresis loop similar to the exchange bias effect in a magnetic heterostructure.

08. Oxide Semiconductors

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Bharat Jalan

University of Minnesota, USA

Biography

Bharat Jalan is a professor, and Shell chair in the Department of Chemical Engineering and Materials Science at the University of Minnesota, Twin Cities where he leads the quantum materials design and synthesis Group. Jalan also serves as the Director of Graduate Studies for Materials Science and Engineering in addition to holding graduate faculty appointment in the Department of Physics, and the Department of Electrical and Computer Engineering at the University of Minnesota.

His interests are in study of structure defect-electronic properties relationships of functional oxide films and artificially designed structures. Jalan was awarded the highly competitive Young Investigator MBE Award, conferred by the 19th International Conference on Molecular Beam Epitaxy in Montpellier, France in September 2016. Jalan has received several awards including the Air Force Office of Science Research Young Investigator Award (2016), Royal Society of Chemistry Emerging Young Investigator (2017), and American Association for Crystal Growth Young Author Award (2017) and the prestigious 2017 AVS Paul Holloway Young Investigator Award. He received the highly prestigious presidential early career awards for science and engineers (PECASE) from the Office of Science and Technology (OSTP) White House. This citation reads “for innovative research at the frontier of science and technologies, and the exceptional potential to shape the future through intellectual and inspired leaderships.” He also won the highly prestigious 2021 AVS Peter Mark Memorial award “For excellence and international leadership in metal-organic molecular-beam epitaxy of complex oxide heterostructures for new electronic materials”. And now, just a few weeks ago, he was recognized by the National academy of Engineering as a highly accomplished early-career engineers. Jalan has (co)-authored more than 100 peer-reviewed publications and given more than 90 invited talks and colloquiums.

Jalan received a BS dual degree in MSE from Indian Institute of Technology (IIT) Madras in India (2006) and a PhD degree in Materials Science from the University of California, Santa Barbara (2011). From 2011-2016, he was an assistant professor at the University of Minnesota, Twin Cities and was promoted to the associate professor in 2017 and to the rank of a full professor in 2022.

Lecture Summary

Perovskite Stannates as High Mobility Oxide Semiconductors

Materials with wide bandgap, high conductivity and high electrical breakdown voltage are of significant interest for power electronics and transparent conducting applications. Stannates (BaSnO3, SrSnO3 and CaSnO3) meet these criteria with the added benefits of having perovskite structure. I will present our group’s effort in developing all-three stannates in thin film form using a novel radical-based hybrid molecular beam epitaxy (MBE) approach. I will present a comprehensive growth, and electronic transport study of these films yielding the record-high conductivity, mobility in these optically transparent films through defect management. I will present the important role of defects such as dislocations, and non-stoichiometry on electronic transport in addition to discussing different scattering mechanisms that limit the room temperature electron mobility. I will present pathways to enhance electron mobilities towards high room-temperature mobility oxide heterostructures using band structure engineering.

09. Nanocarbon and Novel 2D Materials/Devices

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Se-Young Jeong

Pusan National University, Korea

Biography

Se-Young Jeong is a Professor in the Department of Optics and Mechatronics engineering at Pusan National University. He serves as the Director of the Crystal bank institute. He received BS and MS from Pusan National University (1981 and 1985) and a Ph.D. from Koln University, Germany (1990), Then, he worked in ETRI for 1 year and in 1992, he joined Pusan National University as a faculty. He studied at the beginning mostly in the areas of dielectric single crystals, dilute magnetic semiconductors, and bulk metal single crystals. His current research interests are the growth of 2D metal single crystal thin film, electronic behavior in 2D metal, and controlling and blocking oxidation as a tensor quantity.

Lecture Summary

A Growth of Cu(111) Thin Film with A Flat-Surface by Atomic-Sputtering Epitaxy and Colossal Oxidation Resistance

The properties including oxidation phenomena of metal single-crystal thin films have never been clearly unveiled because unlike foils, the crystallinity of film relies strongly on the underlying substrate lattices [1] and thus the formation of twin boundary (TB) and grain boundary (GB) is inevitable. The formation of TB in thin film crystal is attributed to the lattice mismatch with the substrate. The effects of GB and TB on the chemical bonding and electrical properties of copper are very different. In this study, we discuss the peculiarities of the chemical and electrical properties of thin films grown by atomic-sputtering epitaxy (ASE).
The ASE-grown thin film consists mostly of flat surfaces and occasional mono-atomic steps[2]. A mono-atomic step edge is as impervious as a flat surface to oxygen and the ultra-flat surface is appropriate for the growth of 2D materials such as grahphene[2, 3]. They also provide the abrupt oxide layer controlled like vector-quantity, when oxidized intentionally at a high temperature [4]. In this talk, oxidation physics, flat-surface-assisted phenomena, and a part of metaltronics are introduced.
A study of metal is considered to be far from that of semiconductor, but considering the serious problems in the semiconductor manufacturing process as the structure design becomes more complex, the role of metal thin films becomes more important.

1. T.W. Ha et al., Nature communications (to be published 2023)
2.S. J. Kim, et al., Nature 603, 434-438, (2022).
3. VL Nguyen, et al., Nature Nanotech. 15, 861-867, (2020).
4. S. J. Kim, et al., Adv. Mat. 202007345, (2021).

09. Nanocarbon and Novel 2D Materials/Devices

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Soaram Kim

Texas A&M University, USA

Biography

Soaram Kim is an Assistant Professor in the Department of Electrical and Computer Engineering with a joint appointment in the Center for Remote Health Technologies and Systems at Texas A&M University. He received his B.S. and M.S. degrees in Nano Engineering from Inje University in 2012 and 2014, respectively, and the Best Thesis Award from Inje University in 2014. He received his Ph.D. degree in Electrical Engineering from Clemson University in 2018. Following his graduation, he served as a Postdoctoral Researcher at the Institute for Research in Electronics and Applied Physics, University of Maryland, College Park from 2018 to 2021. He also served as a Robert J. Eichelberger Distinguished Postdoctoral Fellow residing at the U.S. Army Research Laboratory (Adelphi, Maryland) for a year before joining Texas A&M University. He has been a conference technical director for the 62nd Electronic Materials Conference (EMC 2020, virtual) and an organizer for the Symposium on 2D and other Low-dimensional Materials (American Conference on Crystal Growth and Epitaxy & US Workshop on Organometallic Vapor Phase Epitaxy) since 2021. His research interests include flexible/wearable electronics, multifunctional sensors, health/environmental monitoring systems, and energy harvesting and storage devices. He has published over 65 journal articles and presented more than 70 conference talks. His research has also resulted in 3 issued patents and 2 invention disclosures.

Lecture Summary

Quasi-Freestanding Epitaxial Graphene-based IoT Sensors for Remote

Common air pollutants, including greenhouse gases, volatile organic compounds, and even cleaning/sanitizing products for coronavirus, have adverse effects on the human body and the environment as they have been linked to cancers, asthma, and various neurological problems. In addition, COVID-19 by itself is a newly emerging human infectious disease and causes respiratory illnesses of varying severity from the common cold to fatal pneumonia in both humans and animals. Therefore, the need and demand for low power, sensitive, selective and robust sensors at room temperature are significant in many fields, including military, environmental, biomedical, agricultural, automotive, wearable, and industrial emission applications, due to the impact of COVID-19 crisis. This talk will provide an overview of my research interests in biological and chemical sensor development for remote health/environmental monitoring systems and highlight some of my previous work on materials synthesis and sensing applications.

10. Organic Semiconductors and Flexible Materials

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Namyoung Ahn

Los Alamos National Lab, USA

Biography

Solution-processable optical gain materials such as organic semiconductors, perovskites, and colloidal nanocrystals have attracted worldwide attention for emerging laser technologies. The realization of electrically pumped laser diodes employing this class of materials have been not demonstrated yet due to multiple remaining challenges including material stability, not sufficient optical gain, and photonic integration. Out of these solution-processable materials, colloidal nanocrystals show superior optoelectronic properties for lasing devices. These include tunable emission wavelength, low optical gain threshold, strong optical gain and high stability under ultrahigh current density operation. Especially, development of continuously-graded nanocrystals exhibiting strongly suppressed Auger recombination have started to open a new possibility of realization of solution-processable laser diodes. In this presentation, the status of colloidal nanocrystal lasing devices will be discussed together with challenges faced in the course of development of lasing devices and corresponding solutions to tackle the challenges. Also, colloidal nanocrystal lasing devices as a technologically viable device in future laser technologies will be prospected.

Lecture Summary

Development of Colloidal Quantum Dot Laser Diodes

Solution-processable optical gain materials such as organic semiconductors, perovskites, and colloidal nanocrystals have attracted worldwide attention for emerging laser technologies. The realization of electrically pumped laser diodes employing this class of materials have been not demonstrated yet due to multiple remaining challenges including material stability, not sufficient optical gain, and photonic integration. Out of these solution-processable materials, colloidal nanocrystals show superior optoelectronic properties for lasing devices. These include tunable emission wavelength, low optical gain threshold, strong optical gain and high stability under ultrahigh current density operation. Especially, development of continuously-graded nanocrystals exhibiting strongly suppressed Auger recombination have started to open a new possibility of realization of solution-processable laser diodes. In this presentation, the status of colloidal nanocrystal lasing devices will be discussed together with challenges faced in the course of development of lasing devices and corresponding solutions to tackle the challenges. Also, colloidal nanocrystal lasing devices as a technologically viable device in future laser technologies will be prospected.

10. Organic Semiconductors and Flexible Materials

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Han-Hee cho

UNIST, Korea

Biography

Han-Hee Cho is an Assistant Professor in Materials Science and Engineering at Ulsan National Institute of Science and Technology (UNIST). He studied at Korea Advanced Institute of Science and Technology (KAIST), where he obtained a Bachelor’s degree in Chemical & Biomolecular Engineering. He joined the research group of Prof. Bumjoon Kim in Chemical & Biomolecular Engineering at KAIST and worked to control the electrical and structural properties of conjugated polymers for their use in organic solar cells. He received his Ph.D. in 2017 and shortly after, joined the Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO) headed by Prof. Kevin Sivula at EPFL in Switzerland, where he worked as a postdoctoral researcher to demonstrate organic semiconductor photoelectrochemical cells before joining UNIST in 2022. Currently, he leads a research group at UNIST with the aim of demonstrating next-generation organic semiconductor photoelectrodes and photocatalysts for efficient and sustained production of solar fuels.

Lecture Summary

A Photoelectrochemical Tandem Cell Based on Organic Semiconductors for Overall Water Splitting

Given the terrestrial abundance of H2O and enormous solar energy, solar-driven water splitting into hydrogen (H2) and oxygen (O2) by photoelectrochemical (PEC) cells has been recognized as one of leading approaches to reduce our dependence on fossil fuels since hydrogen can be converted into electrical energy using a fuel cell. However, the identification of ideal light harvesting semiconductors that meet requirements for industrialization of solar water splitting remains elusive. In this talk, I will present a series of studies to demonstrate highly efficient and robust PEC cells based on organic semiconductors (OSs). In- depth study using sacrificial agents for photoreduction and photooxidation is carried out to identify critical parameters affecting the conversion efficiency and operational stability of organic semiconductor PEC (OPEC) cells. By leveraging the insights gained in this study, the optimized OS-based photocathode and photoanode show outstanding performance and unprecedented robustness. Furthermore, combining these OS-based photoelectrodes leads to the demonstration of a large-area OPEC tandem cell for overall water splitting which attains a solar-to-hydrogen (STH) conversion efficiency of 0.3% under unassisted two- electrode operation (1 Sun illumination). Consequently, this work establishes the use of OSs as a promising path towards the demonstration of efficient, scalable, and economical photoelectrochemical cells for solar water splitting.

11. Optoelectronics, Integrated Photonics, and III-V Electronic Devices on Si

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Kei May Lau

The Chinese University of Hongkong, HongKong

Biography

Kei May Lau is a Research Professor in the Department of Electronic Engineering at the Chinese University of Hong Kong. She was a Chair Professor of Electronic and Computer Engineering at the Hong Kong University of Science & Technology (HKUST). She received her degrees from the University of Minnesota and Rice University and served as a faculty member at the University of Massachusetts/Amherst until 2000. Prof. Lau is a Fellow of the IEEE, Optica (formerly OSA), and the Hong Kong Academy of Engineering Sciences. She is also a recipient of the IET J J Thomson medal for Electronics, Optica (formerly OSA) Nick Holonyak Jr. Award, IEEE Photonics Society Aron Kressel Award, US National Science Foundation (NSF) Faculty Awards for Women (FAW) Scientists and Engineers, and Hong Kong Croucher Senior Research Fellowship. She was an Editor of the IEEE Transactions on Electron Devices (1996-2002) and Electron Device Letters (2016-2019), an Associate Editor for the Journal of Crystal Growth and Applied Physics Letters. Lau’s research work is focused on the development of monolithic integration of semiconductor quantum devices on industry-standard silicon substrates.

Lecture Summary

Monolithic lasers/photodetectors Grown on SOI for Silicon Photonics

Si photonics has been developed to enable the next generation tele- and data-communications taking advantage of the mature silicon CMOS technologies. It is also fueling various applications such as imaging, sensing, spectroscopy, quantum science and optical metrology. To efficiently couple light between active and passive components for Si photonics, we developed a novel lateral aspect ratio trapping (LART) technique to grow lasers and high-speed photodetectors on patterned commercial SOI substrates for integrated Si photonics. Multimode and single-mode lasing from lateral quantum wells (QWs) as the gain media using LART have been achieved in the 1433 -1630 nm band with varying dimensions of lasers. High-performance PDs coupled to Si tapers were also constructed on the monolithic InP/SOI platform with laterally grown p-i-n structures and show open eye diagram exceeding 100 Gb/s. The talk will introduce Si photonics and the motivation of our research for future electronic/photonic integration on the silicon platform.

SS1. Emerging Materials and Devices

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Hyungjin Kim

Yonsei University, Korea

Biography

Hyungjin Kim is an Assistant Professor in the department of Materials Science and Engineering at Yonsei University. He earned his bachelor’s and master’s degree in Electrical and Computer Engineering at Seoul National University in 2014 and 2016, respectively, and Ph.D. in Electrical Engineering and Computer Sciences at University of California, Berkeley in 2021. Before joining Yonsei University, he also worked at Stanford University as a postdoctoral fellow conducting research on improving the properties of nanoscale semiconductors and solving the challenges in their next-generation device applications. During his Ph.D., he was a recipient of Samsung Scholarship and he has published first-authored papers in international peer-reviewed journals including Nature and Science. His research is at the multidisciplinary interface between materials science, electrical engineering, chemistry, and physics where he pursues energy-efficient nanoelectronics and optoelectronics.

Lecture Summary

Monolayer Semiconductors with High Luminescence Efficiency

Two-dimensional (2D) transition metal dichalcogenide (TMDC) monolayers such as MoS2, WS2, and WSe2 have aroused significant attention among researchers over past years due to their unique properties which possess the promise for future optoelectronic applications. Atomically thin TMDC monolayers exhibit the tunability of their properties through electric field and strain as well as the capability to achieve van der Waals heterostructures free of lattice mismatch. While these advantages enable their application for various optoelectronic devices including light-emitting diodes (LEDs) and photodetectors, one of the main constraints for their implementation in practical applications is the low photoluminescence (PL) quantum yield (QY), which is reported in the range of 0.01 to 6% at room temperature. PL QY is a key figure of merit in optoelectronic applications because it directly determines the maximum efficiency that the device can achieve.
In this work, 2D TMDC monolayers with high optoelectronic quality were demonstrated in both mechanically exfoliated and synthesized samples through proper material processing [1, 2]. Moreover, we achieved near-unity PL QY in monolayers at all exciton densities, which paves the way for developing LEDs that will retain high efficiency at all brightness [3].

SS1. Emerging Materials and Devices

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Chao-Ching Cheng

Taiwan Semiconductor Manufacturing Company, Taiwan

Biography

Chao-Ching (Albert) Cheng joined Taiwan Semiconductor Manufacturing Company (TSMC) since 2009 and currently is technical manager in Corporate Research in TSMC. He is responsible for the technology development of two-dimensional (2D) materials and oxide semiconductors. Till now he has co-published total 12 IEDM and 7 VLSI conference papers and over 33 journal papers, covering the material and device studies of TMD, Ge, and III-V materials. He owned 67 US patents related to the SixGe1-x logic technologies and novel electronics based on low-dimensional materials. Albert Cheng also had the working expertise in the module development of SiGe S/D epitaxy (2011-2012) and Ge gate dielectrics (2013-2014) and moved to the process integration and architecture pathfinding of Si-based CMOS technologies from 2015 to 2018. Prior to joining TSMC, he received the M.S. and Ph.D degrees of Electrical Engineering from National Chiao-Tung university in 2005 and 2009 for high mobility III-V and Ge device research.

Lecture Summary

Gate-All-Around Short-Channel Transistor of 2D Materials

Si nanosheet (NS) has been considered as the most promising architecture for next generation device. Further down the road, scaling Si channel thickness by using 2D semiconductors such as transition metal dichalcogenides (TMDs) in their monolayer form can enable the gate length scaling because of the better electrostatic control. It makes NS device integration with monolayer TMDs as an interesting option in future logic transistor. Both the performance and process of the stacked 2D sheet transistors are still new field to explore. In this talk, we will present the first demonstration of monolayer TMD single sheet FET in a gate-all-around (GAA) configuration with high-k metal gate (HKMG). How to enable the conformal and high-quality gate dielectrics on TMD is discussed. The LG=40 nm GAA transistor of monolayer MoS2 channel displays a high ION ~410 A/ m, large on-off ratio ~8 orders, and positive VTH ~1.4 V at VDS = 1 V. Furthermore, an integration flow specific for stacked TMD NS device is proposed and critical module challenges are addressed. The demonstration of MoS2 NS performance and stacked NS modules in this work further clarifies the value proposition in 2D materials and their potential in semiconductor industry.

SS2. Self-Driving Mobility and AI Applications

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Byungjin Cho

Chungbuk National University, Korea

Biography

Byungjin Cho is an Associate Professor in the Department of Advanced Material Engineering at Chungbuk National University (CBNU), Korea. He received both his Doctor and Master of Science degrees from Gwangju Institute of Science and Technology (GIST) in Korea in 2012, followed by a postdoctoral researcher position at UCLA. After that, he joined the Korea Institute of Materials Science in Korea, and finally joined CBNU in 2017.

Cho's research focuses on the synthesis of atomically thin layered nanomaterials and their multi-electronic applications, such as high-performance transistors, neuromorphic synaptic devices to mimic the information processing mechanism of the human brain, and photonic devices to detect low-energy IR wavelengths. He investigates the physical and electrical properties of these electronic devices, with a particular emphasis on their working mechanisms. His further work aims to develop advanced photonics and electronics for practical applications.

He has received numerous awards and honors for his work, including the President's Award of the Korea Industry-Academia Cooperation Association, the KIMS Talent Award, and multiple Best Poster Awards. He has been invited to present his research at conferences and seminars. He is currently the editor of a special issue of Nanomaterials journal since 2022 and has served as a session committee for Nano Korea 2021~2023 Symposium.

Cho has published his research in over 70 academic journals and provided over 100 poster and oral presentations at international and local conferences. He has collaborated with researchers from other research universities and institutions in Korea and abroad. He has also served as the head of the Department of Advanced Material Engineering at CBNU.

As a professor, he is committed to mentoring the next generation of materials scientists and engineers. He has advised numerous graduate students and postdoctoral researchers, many of whom have gone on to successful careers in academia and industry. He is also actively involved in promoting diversity and inclusion in 2D material fields, serving as a mentor and advocate for underrepresented groups in his department and beyond.

Lecture Summary

Strategy to implement the synaptic devices with heterosynaptic plasticity

Artificial synapses based on two-dimensional (2D) MoS2 memtransistors have recently attracted considerable attention as a promising device architecture for complex neuromorphic systems. However, previous memtransistor devices occasionally cause uncontrollable analog switching and unreliable synaptic plasticity due to random variations in the field-induced defect migration. Thus, it is necessary to demonstrate the synaptic devices with reliable memtransistor switching property. Here we provide the case studies to enable the promising concept.
First, we demonstrate a highly reliable 2D MoS2/oxide heterostructure memtransistor device, in which the oxide interlayer thickness is a critical material parameter to induce and tune analog switching characteristics of the 2D MoS2. Ultraviolet photoelectron spectroscopy and photoluminescence analyses reveal that the Schottky barrier height at the 2D channel-electrode junction of the MoS2/oxide heterostructure films is increased, leading to more effective contact barrier modulation and allowing more reliable resistive switching. The 2D/oxide memtransistors attain dual-terminal (drain and gate) stimulated heterosynaptic plasticity and highly precise multi-states. In addition, the memtransistor devices show an extremely low power consumption of ~6 pJ and reliable potentiation/depression endurance characteristics over 2000 pulses. A high pattern recognition accuracy of ~94.2% is finally achieved from the synaptic plasticity modulated by the drain pulse configuration using an image pattern recognition simulation. Thus, the novel 2D/oxide memtransistor makes a potential neuromorphic circuitry more flexible and energy-efficient, promoting the development of more advanced neuromorphic systems.
Another approach is to demonstrate tunable sulfur vacancy-modulated MoS2 memtransistor using O2 plasma treatment method. The reduction of sulfur concentrations in MoS2 film depending on O2 plasma treatment was analyzed by X-ray photoelectron spectroscopy. The corresponding work function and energy band structure were confirmed by ultraviolet photoelectron spectroscopy and UV-visible spectroscopy analysis. Vibrational modes of the MoS2 film as O2 plasma treatment time were also investigated by Raman spectrometer. The resistive switching characteristics of MoS2 memtransisor were effectively tuned with O2 plasma treatment time and location. Furthermore, the essential synaptic behavior, such as long-term potentiation/depression, were implemented successfully by the drain and gate pulse. The promising results demonstrated by O2 plasma treated MoS2 memtransistor would contribute to the implementation of the reconfigurable neuromorphic computing system.

SS3. High-Resolution and Multi-Functional Display Technology

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Yong-Ho Ra

Jeonbuk National University, Korea

Biography

Research Activity

Epitaxial growth/synthesis of III-nitride materials using MOCVD and MBE technique.
Novel semiconductor nanowire/nanorod, quantum dot and thin film structures
Nano-scale optoelectronic devices (LEDs, LDs, PDs etc) for micro/nano display, real 3D display, smart lighting, lamp applications.

Education

2014 Ph.D. Electronic Information Materials Engineering, Jeonbuk National University, Korea
2010 M.S. Electronic Information Materials Engineering, Jeonbuk National University, Korea
2008 B.S. Electronic Information Materials Engineering, Jeonbuk National University, Korea

Professional Experience

2021-present Associate Professor, Dept. of Advanced Materials Engineering, Jeonbuk National University, yhra@jbnu.ac.kr
2018-2021 Senior Researcher, Optic & Electronic Component Material Center, Korea Institute of Ceramic Engineering & Technology (KICET)
2014-2017 Postdoctoral Fellow, Dept. of Electrical & Computer Engineering, McGill university

Representative Publications ( First-author )

Yong-Ho Ra et al, Ultracompact display pixels: Tunnel junction nanowire photonic crystal laser, Nano Energy, 2021, Vol. 84, p105870.
Yong-Ho Ra et al, Core-shell tunnel junction nanowire white light-emitting diode, Nano Letters, 2020, Vol. 20, p4162-4168.
Yong-Ho Ra et al, An electrically pumped surface-emitting semiconductor green laser, Science Advances, 2020, Vol. 6, eaav7523.
Yong-Ho Ra et al, Scalable Nanowire Photonic Crystals: Molding the Light Emission of InGaN, Advanced Functional Materials, 2017, Vol. 27, p1702364.
Yong-Ho Ra et al, Full-color single nanowire pixels for projection displays, Nano Letters, 2016, Vol. 16, p4608-4615.
Yong-Ho Ra et al, Single nanowire LED using uniaxial and coaxial InGaN/GaN MQWs synthesized by MOCVD, Nano Letters, 2014, Vol. 14, p1537-1545.
Yong-Ho Ra et al, Coaxial InGaN/GaN MQW nanowire arrays on Si substrate for high-performance LEDs, Nano Letters, 2013, Vol. 13, p3506-3516.

Lecture Summary

Group III-Nitride Based Nanorod Structures For Next-Generation Display Applications

The development of next-generation pixels with smaller size, lower power consumption and higher luminance is required for VR and XR display applications. III-nitride based nanorod structures have been employed in a broad range of optoelectronic and electronic devices. Recently, a new approach to fabricating uniform nanorod structures using a selective area epitaxial growth has been reported by a few research groups. The selective area growth approach has shown tremendous promise in controlling directive radiation, in improving carrier injection efficiency, and in tuning uniform wavelength emission, and enhanced light-extraction, by controlling the diameter and location of the nanorods. Here, we investigated the epitaxial growths and optical and electrical characteristics of the nanorod heterostructures by using the selective area epitaxial growth. It is found that, by controlling of spacings and diameters on the nanorods, the optical performance can be drastically improved due to the formation of high-quality crystal structures and the suppression of the defects, controllable light emissions in the GaN nanocrystal. This study provides a new fundamental understanding in the nanorod structures to achieve the high-performance p-i-n structures, which is critically important for a broad range of applications, including electronic and photonic devices.

SS5. Highly Efficient Energy-harvesting Technology

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Jongchul Lim

Chungnam National University, Korea

Biography

Education

2002. 03 - 2009. 02 B.S., Department of Polymer Eng. & Mater. Sci. (double major), Chungnam National University
2009. 03 - 2015.02 Integrated Ph.D., Department of Chemical Engineering, Pohang University of Science and Technology

Experiences & Careers

2020.03 - present Assistant Professor, Graduate school of Energy Science and Technology, Chungnam National University
2015.06 - 2020.02 Post-Doc, Department of Physics, University of Oxford, UK
2015.02 - 2015.06 Post-Doc, Pohang University of Science and Technology

Representative Awards/Publications

“Long-range charge carrier mobility in metal halide perovskite thin-films and single crystals via transient photo-conductivity”, Nature Communications (2022) 13, 4210
“Excellent long-range charge-carrier mobility in 2D perovskites”, Advanced Functional Materials (2022) 32, 2203064
“Exploration of sub-bandgap states in 2D halide perovskite single-crystal photodetector” NPJ 2D Materials and Applications (2022) 6, 43
“Toward Understanding Space-Charge Limited Current Measurements on Metal Halide Perovskites” ACS Energy Letters (2020) 5, 376
“Elucidating the long-range charge carrier mobility in metal halide perovskite thin films” Energy & Environmental Science (2019) 12, 169

Lecture Summary

Insights into Charge Carrier Dynamics in Metal Halide Perovskites

It is important to understand the long-range charge transport within the metal halide perovskite for optimisation of operating devices, where the charges have to travel over on the order of microns, and if these properties change in different carrier density regimes, or through different methods of processing the films. Here this presentation introduces applied methodologies and also highlights an advanced optical and electrical methodologies: Pulsed-voltage space charge limited current (PV-SCLC)[1], Dynamic trapping model (TRPL)[2], Photoinduced transmission and reflection (PITR)[3], Transient photo-conductivity (TPC)[4,5]. With these methods, we accurately estimated the internal free-carrier density during photo-excitation, accounting for both early-time recombination and exciton-to-free-carrier branching ratios to determine long-range charge carrier mobility in metal halide perovskite thin films and single crystals, to be reliable value over many orders of magnitude of charge density. We believe this study is the accurate evaluation of photo-induced long-range mobility of metal halide perovskites, and therefore represents a powerful handle for future optimisation of perovskite solar cells and optoelectronic devices.

SS5. Highly Efficient Energy-harvesting Technology

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Jae Sung Yun

University of Surrey, UK

Biography

Dr. Jae Sung Yun is a Lecturer in Energy Technology at the Advanced Technology Institute, School of Computer Science and Electronic Engineering, University of Surrey, UK. He completed his bachelor's degree in Materials Science and Engineering (MSE) at Yonsei University, Korea in 2008, followed by a Master of Philosophy in MSE at the University of New South Wales, Australia in 2010, and received his PhD in silicon thin film solar cells in 2015. Dr. Yun's research focuses on developing emerging photovoltaic technologies and investigating nanoscale topological defects, using scanning probe microscopy techniques to study the correlation between local topological defects and the properties of photovoltaic devices. He has published over 60 peer-reviewed journal articles and has an h-index of 27.

Lecture Summary

Scanning Probe Microscopy Investigation of Wide Bandgap Halide Perovskites Solar Cells

Halide perovskites have demonstrated exceptional progress in their optoelectronic performance over recent years. Solar cells fabricated utilizing mixed-cations and mixed-halides have allowed for bandgap adjustability for multi-junction solar cells.
In this study, microstructural inhomogeneity in (FAPbI3)x(MAPbBr3)1-x with a bandgap ranging from 1.55 eV to 2.3 eV was explored utilizing several advanced scanning probe microscopy techniques. Kelvin probe force microscopy (KPFM) was utilized to measure contact potential difference (CPD) maps, which revealed an increase in lower CPD grains corresponding to the flat polymorph grains in the topographical map as MAPbBr3 concentration was increased. Chemical component analysis was conducted using helium ion microscopy with secondary ion mass spectrometry to reveal that the flat grains were rich in MA, Pb, and I. Spectral photoluminescence demonstrated clear compositional dependent phase segregation as MAPbBr3 concentration increased, which was responsible for the formation of the abnormal grains. Lastly, light-assisted KPFM measurements revealed that the flat grains contributed to phase segregation.
The results of various microstructural characterizations suggest that the abnormal grains as defect sites are detrimental to phase segregation and ion migration. Therefore, further research in this area is necessary to fully understand the behavior of mixed perovskites and to optimize their performance in optoelectronic devices.

SS6. Advanced Convergence Technologies

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Jarek Dolak

SVCS, Czech

Biography

(Mr.) Jarek Dolak is co-founder and CEO of SVCS Process Innovation, front-end semiconductor equipment manufacturer based in the Czech republic and established in 2000. Jarek graduated in 1985 at Brno Technical University in Electronics and Computer Science, but shortly after political changes in the Eastern Europe (so called “Velvet Revolution”) in 1989 founded at first a trading company and later together with his university school-mate a manufacturing company, that was inspired and motivated by long tradition of semiconductor industry in the former Czechoslovakia. SVCS manufacture front-end thermal reactors (“furnaces”) and other deposition tools together with high-purity gas and liquid delivery systems. Besides several Wafer Fabs in Europe, SVCS customers include leading universities and R&D institutes worldwide.

Lecture Summary

Unknown Silicon Valley in the Heart of Europe

This presentation introduce beautiful mountain area in the center of Europe - in the Czech republic, near a border line with Slovakia and Poland. This area is full of tourists both in summer or winter. Hundreds of historical movie makers shoot here the scenery of old wooden villages and historical handicrafts. The semiconductor industry was born here in former Czechoslovakia after WW II., started in production of vacuum electron tubes followed by semiconductors only 9 years after invention of transistor in the USA. The company took name of scientist Nicola Tesla. The new age for Czech semiconductor industry started in 1990’s after taking over by US investors from Motorola, followed by onsemi. The new US owners provided to Czech engineers quite independent position in choosing local suppliers and business partners. This enabled formation of the Czech semiconductor ecosystem and resulted in establishment several local equipment manufacturers - one of them is SVCS. The history of SVCS started in refurbishment of obsolete control systems, followed by development own technology first for silicon device. With new strategy of onsemi towards silicon carbide, also SVCS has to change portfolio of own products to support this new and promising technology.

My personal note: I really wonder if such a topic, describing the 32 years of building our small company (we are still < 50 people) would be interesting for your scientific community who will probably come to learn more scientific facts - and I am definitely not a scientist. I will be able to show a few historical pictures, but only limited information about our new high temperature furnace for Silicon Carbide anneal due to competition.

Kazuhiro Ohkawa	King Abdullah University of Science and Technology (KAUST), Saudi Arabia	InGaN-based micro-LEDs fabricated by hydrogen passivation method
Yong-Ho Ra	Jeonbuk National University, Korea	Group III-Nitride Based Nanorod Structures For Next-Generation Display Applications
Jaehoon Lim	Sungkyunkwan University , Korea	Heteroepitaxial Chemistry of Zinc Chalcogenides on InP Nanocrystals Enabling Defect-free Heterointerface

Jin Wook Lee	Sungkyunkwan University, Korea	Characterization and Mitigation of Defects in Metal Halide Perovskites for Optoelectronic Applications
Hui-Seon Kim	Inha University, Korea	Interface engineering for perovskite layer
Jongchul Lim	Chungnam National University, Korea	Insights into Charge Carrier Dynamics in Metal Halide Perovskites
Hui Joon Park	Hanyang University, Korea	Sn-based perovskite: high performance Pb-free perovskite photodetector and all-perovskite tandem solar cell
Wooseok Yang	Sungkyunkwan University, Korea	Efficient unassisted solar water splitting by photoelectrochemical tandem cells
Sang-Wan Ryu	Chonnam National University, Korea	Hierarchical Si-ZnO Nanowires for Photoelectrochemical Solar Hydrogen Generation
Jae Sung Yun	University of Surrey, UK	Scanning Probe Microscopy Investigation of Wide Bandgap Halide Perovskites Solar Cells

Invited Speakers

01. Epitaxy, Fabrication, and Related Technologies

02. RF and THz Devices

03. High Power and High Frequency Electron Devices

04. Wide Bandgap Semiconductors

05. Photonic and Optoelectronic Devices and Related Technologies

06. Semiconductor Physics, Spintronics, Ferroelectronics, and Novel Device Concepts

07. Nanostructure and Nano Characterization

08. Oxide Semiconductors

09. Nanocarbon and Novel 2D Materials/Devices

10. Organic Semiconductors and Flexible Materials

11. Optoelectronics, Integrated Photonics, and III-V Electronic Devices on Si

SS1. Emerging Materials and Devices

SS2. Self-Driving Mobility and AI Applications

SS3. High-Resolution and Multi-Functional Display Technology

SS4. New-Conceptual Quantum Information and Communication

SS5. Highly Efficient Energy-harvesting Technology

SS6. Advanced Convergence Technologies

Invited Speakers

01. Epitaxy, Fabrication, and Related Technologies

02. RF and THz Devices

03. High Power and High Frequency Electron Devices

04. Wide Bandgap Semiconductors

05. Photonic and Optoelectronic Devices and Related Technologies

06. Semiconductor Physics, Spintronics, Ferroelectronics, and Novel Device Concepts

07. Nanostructure and Nano Characterization

08. Oxide Semiconductors

09. Nanocarbon and Novel 2D Materials/Devices

10. Organic Semiconductors and Flexible Materials

11. Optoelectronics, Integrated Photonics, and III-V Electronic Devices on Si

SS1. Emerging Materials and Devices

SS2. Self-Driving Mobility and AI Applications

SS3. High-Resolution and Multi-Functional Display Technology

SS4. New-Conceptual Quantum Information and Communication

SS5. Highly Efficient Energy-harvesting Technology

SS6. Advanced Convergence Technologies

Biography

Lecture Summary

III-V heteroepitaxy on lattice mismatched (111)A-oriented substrates: application for the quantum light emitter and infrared detector

Biography

Lecture Summary

Selective Area Regrowth and Doping for Vertical GaN Power Devices

Biography

Lecture Summary

Development of Indigenous Infrared Focal Plane Arrays at IIT Bombay

Biography

Lecture Summary

Engineering Reliability against Dislocations in InAs Quantum dot Lasers on Silicon

Biography

Lecture Summary

Fabrication Process Technology of InP-based Tera-Hertz ICs for Beyond 5G / 6G Wireless Communication Networks

Biography

Lecture Summary

Cryogenic microwave noise characterization of GaN high electron mobility transistors

Biography

Lecture Summary

Atomic Layer Deposition of BeO for Wide-Bandgap Semiconductor Heterostructures

Biography

Lecture Summary

Study on Dynamic RON in AlGaN/GaN HEMTs Using Substate Bias Measurement

Biography

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TCAD Modeling of β-Ga2O3 based High Power and High Frequency Devices

Biography

Lecture Summary

Gallium oxide polymorph heterostructures: physics, fabrication, and potential applications

Biography

Lecture Summary

Ultrawide bandgap CMOS and NMOS platform for heterogenous power integration

Biography

Lecture Summary

WBG Power Device Modelling, Characterizations, and Reliability Studies

Biography

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Advances and Challenges in Transparent AlGaN UVB LEDs

Biography

Lecture Summary

Highly Spatially Resolved STEM-CL Characterization of GaN-Based Power Devices

Biography

Lecture Summary

Strain evolution and ex-situ strain-profiling in GaN-related devices by surface-plasmon enhanced Raman spectroscopy

Biography

Lecture Summary

GaN-based superluminescent diodes: advances and perspectives

Biography

Lecture Summary

Structural Defects in Ultra-Wide Bandgap Homoepitaxial Ga2O3 Epilayers

Biography

Lecture Summary

Recent Progress in Blue, Green and Red III-Nitride Epitaxy for Conventional and Micro LED Applications

Biography

Lecture Summary

On-chip light sources for integrated photonic quantum computing

Biography

Lecture Summary

Biography

Lecture Summary

Novel epitaxy of III-V for fabricating high-density hetero-integrated optoelectronics and flexible devices