特邀演講

Invited Talk 1 [A1] – 10/27 (Thu.) 13:00-13:25

Dr. TZUNG-FANG GUO 郭宗枋

國立成功大學光電科學與工程學系 特聘教授
Department of Photonics, National Cheng Kung University, TAIWAN

Characterize and retard the impact of mobile ions in hybrid perovskite-based light-emitting diodes
Tzung-Fang Guo, Teng Lam Shen, Aswaghosh Loganathan, Thi Hoai Do, and Yu-Ting Chen Department of Photonics, Advanced Optoelectronic Technology Center
National Cheng Kung University

Abstract
Herein, the aspects of ion migration in polycrystalline CH3NH3PbBr3 thin film and their phenomenal influences on the output performance of perovskite-based optoelectronic devices is reported. The physical insight of bias-induced migration of mobile ions in the perovskite active layer effectuating the increased output performance of devices as a function of current density is directly evidenced using the capacitance spectroscopy.[1] Adding the zwitterion molecule, Choline chloride (Ch.Cl), in CH3NH3PbBr3 precursor solution for preparing polycrystalline perovskite film effectively passivates the charged defects, either positively or negatively, in organic-inorganic halide perovskite and most importantly interferes the migration of ions crossing the grains as verified by the higher calculated magnitude of the activation energy for the migration of mobile ions. As a result, the Ch.Cl-additive devices exhibited the rather stable electroluminescence (EL) and luminous efficiency (LE) magnitude under the electric bias. EL magnitude increases linearly as a function of current density, revealing the epitome of output characteristics for decent diodes. To suppress the influence of the migrating ions on the output performance of operating perovskite-based optoelectronic devices entails appropriate passivation of the grain interfaces in polycrystalline perovskite active layer, a key issue before we step further to advance the efficiencies and the operational stabilities of perovskite devices.

References
[1] Shen, T. L.; Loganathan, A.; Do, T. H.; Wu, C.-M.; Chen, Y.-T.;   Chen, Z.-J.; Chiu, N.-C.; Shih, C.-H.; Wang, H.-C.; Chou, J.-H.; Hsu, Y.-Y.; Liu, C.-C.; Chang, Y.-C.; Fu, Y.-S.; Lai, W.-C.; Chen, P.-T;. Wen, T.-C.; Guo, T.-F. Characterize and retard the impact of the bias-induced mobile ions in CH3NH3PbBr3 perovskite light-emitting diodes. Adv. Optical Mater. 10, 2101439 (2022).

Biography
Professor Tzung-Fang Guo received Ph.D. degrees in Materials Science and Engineering from University of California Los Angeles in 2002. He became the faculty at Department of Photonics, National Cheng Kung University, Taiwan in 2003 and served the Chairman in 2012 to 2018. His research focuses on high performance O/PLEDs, polymer PVs, n-type pentacene OTFTs, and the magnetic field effect of organic electronic devices. He firstly developed the perovskite-based hybrid solar cells of OPV (p-i-n) device configuration and applied p-type nickel oxide electrode interlayer in fabricating efficient perovskite solar cells and LEDs.

 

Invited Talk 2 [B1] – 10/27 (Thu.) 13:00-13:25

Dr. Pei-Wen Li 李佩雯
國立陽明交通大學電子研究所 教授

Institute of Electronics, National Yang Ming Chiao Tung University, TAIWAN

The Wonderful World of Designer Germanium Quantum Dots
Pei-Wen Li,
Institute of Electronics, National Yang Ming Chiao Tung University, Taiwan

Abstract

Cutting-edge research on Si-based quantum dots (QDs) has opened up access to wide-ranging applications in electronics, photonics, quantum computing, and sensing. The “holy grail” for device manufacturers is to achieve scalability through precise control and repeatable fabrication of QDs with desired shapes, sizes, and ac-curate placement for predictable electrical and optical proper-ties. A Bohr radius of 5 nm in Si dictates the fabrication of ultrasmall Si QDs, which are difficult to controllably produce using either self-assembly or lithographic techniques. In contrast, a large Bohr radius of 25nm in Ge enables easier modification of electronic structures using Ge QDs, imposing less stringent demands on lithographic control. Starting with our remarkable discovery of spherical germanium (Ge) QD formation, we have embarked on an exciting journey of further discovery, all the while maintaining CMOS-compatible processes. We have taken advantage of the many peculiar and symbiotic interactions of Si, Ge and O interstitials to create a novel portfolio of electronic, photonic and quantum computing devices. This paper summarizes several of these completely new and counter-intuitive accomplishments. Using a coordinated combination of lithographic patterning and self-assembly, size-tunable spherical Ge QDs were controllably placed at designated spatial locations within Si-containing layers. We exploited the exquisite control available through the thermal oxidation of Si1-xGex patterned structures in proximity to Si3N4/Si layers. Our so-called “designer” Ge QDs have succeeded in opening up myriad device possibilities, including paired QDs for qubits, single-hole transistors (SHTs) for charge sensing, photodetectors and light-emitters for Si photonics, and junctionless (JL) FETs using standard Si processing.

Biography
PEI-WEN LI received her Ph.D. degree from Columbia University in New York city, in Electrical Engineering in 1994. She is a Professor in Institute of Electronics and served as the Director of Nano Facility Center at National Chiao Tung University (NCTU) in Hsinchu. Prior to joining NCTU in 2015, she has been the Distinguished Professor (2006-2015), the Chair of Electrical Engineering Department (2007-2010), Director of Nano Science and Technology (2012-2015), and Associate Dean of Academic Affair (2013-2015) in National Central University. She was a Research Visiting Scholar with Caltech in 2011-2012. She has also worked with Vanguard International Semiconductor Corporation on DRAM technology integration in 1995-1996. Her research themes focus on experimental silicon-germanium nanostructures and devices, encompassing germanium quantum-dot single electron transistors, photodetectors, nonvolatile memory, and energy saving/harvest (photovoltaic and thermoelectric) devices, making use of self-assembly nanostructures in silicon integration technology. She is an IEEE Distinguished Lecturer and serves VLSI Technology and Education committees of IEEE EDS. She has served on various important conference committees, e.g., IEEE SNW, IEEE EDTM, SSDM etc. She is also the Editor Board Member of Applied Physics A-Materials Science & Processing, Springer. She was awarded Distinguished Professor from Chinese Electrical Engineering Society (2015) and Top 10 Rising Stars in Taiwan (Science and Technology) from Central News Agency in 2008.
Invited Talk 3 [C1] – 10/27 (Thu.) 13:00-13:25

Dr. Peide (Peter) Ye 葉培德 教授

Elmore School of Electrical and Computer Engineering, Purdue University, USA
Atomic-layer-deposited atomically thin In2O3 transistors for BEOL logic and memory applications
Peide (Peter) Ye
Elmore School of Electrical and Computer Engineering, Purdue University, USA

Abstract
In this talk, we report on the first demonstration of atomically thin In2O3 channel for logic and memory devices by a back-end-of-line (BEOL) compatible atomic layer deposition (ALD) process [1,2]. High performance planar In2O3 transistors with high mobility of 113 cm2/V⋅s and record high maximum drain current of near 20 mA/um are achieved by gate-all-around structure and thermal engineering. High-performance ALD In2O3 based zero-VGS-load inverter is demonstrated with maximum voltage gain of 38 V/V and minimum supply voltage (VDD) down to 0.5 V. ALD In2O3 3D Fin transistors are also demonstrated, benefiting from the conformal deposition capability of ALD [3]. High-performance In2O3 ferro-electric transistors are demonstrated using ALD HfZrO2 gating with
>2.2V large memory window, >10 years retention and >109 endurance [4, 5]. These results suggest ALD oxide semiconductors and devices have unique advantages and are promising toward BEOL-compatible monolithic 3D integration [6].
1. M. Si et al. IEEE EDL 42(2), 184-187, 2020.
2. M. Si et al. Nano Lett. 21 (1), 500-506, 2020.
3. M. Si et al. VLSI, T2.4, 2021.
4. Z. Lin et al. IEDM, TF17.4, 386, 2021.
5.  Z. Lin et al. VLSI, TF13-2, 2022.
6.  M. Si, Z. Lin et al. Nature Electronics 5(3), 164-170, 2022.

Biography
Dr. Peide Ye is Richard J. and Mary Jo Schwartz Professor at School of Electrical and Computer Engineering. His research focuses on atomic layer deposition and its integration on various novel channel materials including III-V, Ge, 2D materials and complex oxides. He obtained his Ph.D. from Max-Planck Institute for Solid State Research in Germany and postdoc training at NTT Basic Research Laboratory, National High Magnetic Field Laboratory and Princeton University. He worked for Bell Labs of Lucent Technologies and Agere Systems before joining Purdue faculty in 2005. Prof. Ye received the 2011 IBM Faculty Award, Sigma Xi Award and Arden Bement Jr. Award. He is IEEE Fellow and APS Fellow for his contributions to materials and device development for compound semiconductor MOSFETs. Prof. Ye is also recognized as a Highly Cited Researcher among 6000 world wide in all fields.

Invited Talk 4 [D1] – 10/27 (Thu.) 13:00-13:25

Dr. Chao-Yu Chen 陳昭宇
國立成功大學光電科學與工程學系 特聘教授

Department of Photonics, National Cheng Kung University, TAIWAN

Characteristics of Halide Perovskites
via Low-pressure Vapor-assisted Solution Process (LP-VASP)
Hung-Hsiang Yeh, Yu-An Chen, Wei-Ting Hung, Ming-Hsien Li,
Peter Chen* Dept. Photonics, National Cheng Kung University, Taiwan

Abstract
The halide perovskites materials have received exceptional attention for various photonics applications due to their unique materials characteristics. In this presentation, we will show halide perovskites thin film made of low-dimensional/3D mixed structure fabricated via Low-pressure vapor-assisted solution process (LP-VASP) which demonstrated for the first to synthesis Low-dimensional and 3D mixed perovskite by vapor phase method. Their performances in photovoltaic and non-linear optical properties will be presented and discussed. Such families of hybrid organic-inorganic halide perovskite semiconductors are promising candidates for next generation photonic and applications such as solar cells, light-emitting diode, and lasing devices. The slightly 2D doped perovskite showed larger grain size and better photovoltaic performances in both power conversion efficiency and stability. For highly 2D doped perovskite thin film, we observed multiple PL emission spectra with significant multiphoton absorption characteristics, which implies the co-existence of multiple n-layered perovskites domains in one film. The nonlinear optical effects and materials properties are characterized in detail by multiphoton spectroscopy, KPFM, TR-PL, and PL mapping.

Figure 1. (a) Cross sectional SEM image of highly efficient perovskite solar cell made of Low-pressure vapor-assisted solution process (LP-VASP). (b) Multiphoton PL from highly 2D layer doped perovskite.

References
1)  Ming-Hsien Li, Hung-Hsiang Yeh, Yu-Hsien Chiang, U-Ser Jeng, Chun-Jen Su, Hung-Wei Shiu, Yao-Jane Hsu, Nobuhiro Kosugi, Takuji Ohigashi,Yu-an Chen, Po-Shen Shen, Peter Chen*, Tzung-Fang Guo*. Highly efficient 2D/3D hybrid perovskite solar cells via low-pressure vapor-assisted solution process. Advanced Materials, 2018, 30, 1801401.
2)  Yu-An Chen, Hung Wei Shiu, Yao-Jane Hsu, Laura Mundt, Wei-Ting Hung, Takuji Ohigashi, Ming-Hsien Li*, Peter Chen*, Effect of Large Size A Site Cation on the Crystal Growth and Phase Distribution of 2D/3D Mixed Perovskite Film via Low-Pressure Vapor-Assisted Solution Process, The Journal of Physical Chemistry C, 2021, 125, 26601

Biography
Prof. Peter Chen received his PhD from Photonic Program of EPFL Switzerland in 2009 with research topic focused on solid-state dye-sensitized solar cells under the supervision of Prof. Michael Grätzel. Then he moved to Monash University as a post-doctoral research fellow with Prof. Udo Bach. He joined the Dept. of Photonic in National Cheng Kung University (NCKU, Tainan, Taiwan) in 2010 and became associate Professor and Professor in 2014 and 2017, respectively. Currently his research interests are in the area of various functional materials and devices including hybrid organic–inorganic perovskite-based solar cells (HOIPs), semiconductor-based materials and neuromorphic devices. Prof. Chen has been identified in the list of 2018 Clarivate highly cited researchers (cross field).

Invited Talk 5 [A2] – 10/27 (Thu.) 15:20-15:45

Dr. Chia-Feng Lin 林佳鋒
國立中興大學材料科學與工程學系 教授

Department of Materials Science and Engineering, National Chung Hsing University, TAIWAN

Nitride-based Optoelectronic Devices with Porous-GaN Structure
Chic-Feng Lin
Department of Materials Science and Engineering, National Chung Hsing University, Taichung, Taiwan
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Taiwan

Abstract
High-efficiency GaN-based light emitting diodes (LEDs) and photodiodes have been widely unveiled to study in the visible and ultraviolet spectrum range. The Si-heavy doped n+-GaN:Si layers in the epitaxial structure can be transformed into the conductive porous-GaN structures through the electrochemical etching process. The 20 pairs of n+-GaN:Si/n-GaN:Si stack structure were treated as the porous-GaN/n-GaN distributed Bragg reflectors (DBRs). InGaN LED structure with an embedded porous-GaN DBR structure had small divergent angle and high color purity for the directional-emission micro-LEDs applications. InGaN vertical-cavity surface-emitting lasers at 430nm were demonstrated with top dielectric Ta2O5/SiO2 DBR and bottom porous-GaN DBR structures. The optical properties of the porous-GaN/n-GaN DBR structure has been analyzed through the angle- and polarization-dependent reflectance spectra. The optical birefringence behavior of the InGaN active layer in the resonant cavity were observed clearly through the electroluminescence (EL) spectra. EL emission peaks with high polarization ratio and narrow line-width were observed due to the short resonance cavity effect with the birefringence porous-GaN DBR structure. InGaN-based VCSEL structure consisted of the top dielectic DBR, short cavity length of InGaN active layer and bottom porous-GaN DBR which can be used for high-efficiency optoelectronic applications.

Biography
Chia-Feng Lin received the B.S. degree in Department of Physics from Tunghai University, Taiwan, in 1994, and the M.S. degree in Department of Physics from National Central University, Taiwan, in 1996, and the Ph.D. degree in Electronics Engineering from National Chiao Tung University, Taiwan, in 1999. He joined National Chung Hsing University as a faculty member of the Department of Materials Science and Engineering in February, 2004. His current research interests include material characterization and optical devices fabrication on III-V Nitride compound semiconductor light emitting diodes.
Invited Talk 6 [B2] – 10/27 (Thu.) 15:20-15:45

Dr. Kuei-Shu Chang-Liao 張廖貴術
國立清華大學工程科學系 教授

Department of Engineering and System Science, National Tsing Hua University, TAIWAN
High-k Gate Stack on SiGe/Ge Channel for High Performance CMOS Device
Kuei-Shu Chang-Liao
Department of Engineering and System Science, National Tsing Hua University, TAIWAN

Abstract
Process development of gate stack and channel in CMOS device is the key challenge beyond sub-3 nm technology node. The application of high-k dielectric or alloy in gate stack demonstrates both low EOT and gate leakage current. However, carrier mobility degradation caused by high-k gate dielectric is an issue for high performance device. Ge channel is promising to replace Si due to its higher carrier mobility and compatible material properties. Since the properties of high-k/Ge interfaces are usually poor, the interface quality is a critical issue to realize high performance Ge MOSFETs. In this talk, engineering interface and buffer layers for Ge MOSFETs, HfO2/ZrO2/HfO2 gate stack for FinFET, and Ge CMOS with super-critical fluid treatments will be presented. Low EOT, low gate leakage current, and high mobility in SiGe/Ge MOSFET/FinFET are simultaneously achieved.

Biography
Kuei-Shu Chang-Liao received the B.S. and M.S. degrees in Telecommunication and Electronics from National Chiao Tung University, 1984 and 1989, respectively, and the Ph.D. degree in Electrical Engineering from National Taiwan University in 1992.
In 1992, Dr. Chang-Liao joined the faculty at the National Tsing Hua University where he has been a Professor of Department of Engineering and System Science since 1999. In 2000, he was a visiting research fellow at the Department of Electrical Engineering of Yale University, where he was involved in Flash memory and charge pumping measurement. During 2007-2010, he served as the Associate Chairman of Department of Engineering and System Science, and currently is the Chairman. His current research interests include high-k/metal gate stack processes in FinFET/GAAFET, Ge or SiGe MOS devices, charge-trapping flash memory devices, trap analysis in MOS device by charge pumping measurement, and radiation effects on semiconductor devices.
Dr. Chang-Liao is a Distinguished Lecturer of IEEE EDS, senior member of IEEE, and member of the Electrochemical Society. He served as the Editor of IEEE Electron Device Letters during 2012-15. He received the excellent Industry-Academic Research Award from Ministry of Education in 2003. He has published over 300 papers in prestigious journals and conferences. He has chaired and served as committee members in several international conferences.
Invited Talk 7 [C2] – 10/27 (Thu.) 15:20-15:45

Mr. Thien Luan Phan

Department of Physics and Electronic Engineering,
University of Science (Vietnam National University of Ho Chi Minh City), Vietnam
A biorecognition-element free sensor for the identification and quantification of E.Coli
Thien Luan Phan
Department of Physics and Electronic Engineering, Faculty of Physics and Engineering Physics, University of Science, VNU-HCMC, Vietnam

Abstract
Compared with conventional methods of biosensor technology, label-free methods are becoming popular due to their simplicity and ability to directly detect the target in real-time. Electrochemical impedance biosensors have been studied for qualitative and quantitative detection and monitoring of bacteria by means of the change impedance with captured bacteria in the medium or on electrodes. However, despite the advantages of their label-free nature, these biosensors still rely on biorecognition elements, which present challenge to mass production. To overcome this limitation, an immobilization and biorecognition-element-free detection method would bring new hope for effective biosensor application in the food industry. Aim. A bio-recognition-element free sensor was investigated in this study on the ability to distinguished differents analytes, Escherichia coli and Salmonella. The interdigitated microelectrode (IDμE) sensor is designed and developed with this in mind, with good reliability and affordability. At the frequency of 7.69MHz, the developed sensor can identify Escherichia coli with good selectivity. And at the optimum measurement frequency of 1.3kHz it can correctly quantify E. Coli in a range of measurement (103.2~106 cfu/mL), linearity (R2 = 0.97), sensitivity (18.15 kΩ/log (cfu/mL)), and limit of detection (103.2 cfu/mL).
Fig. Diffrences in Impedance value between E. coli and Salmonella samples with NC at the characteristic frequency of 7.69 MHz.

Biography
Thien Luan Phan is an Assistant Lecturer in the Department of Physics and Electronic Engineering, Faculty of Physics and Engineering Physics, University of Science, VNU-HCMC, Vietnam. He received his Bachelor degree from the Faculty of Physics and Engineering Physics, University of Science, VNU-HCMC, Vietnam, in 2019. He earned his Master degree from Graduate Institute of Biomedical Engineering, College of Engineering, National Chung Hsing University, Taiwan in 2021. He is currently working toward a Ph.D. degree in the Graduate Institute of Biomedical Engineering, College of Engineering, National Chung Hsing University, Taiwan. His research interest includes biomedical engineering, medical instruments, electrochemical impedance and biosensors.
Invited Talk 8 [D2] – 10/27 (Thu.) 15:20-15:45

Dr. Chia-Yun Chen 陳嘉勻
國立成功大學材料科學及工程學系 副教授

Department of Materials Science and Engineering, National Cheng-Kung University, TAIWAN
Toward solution-processed heterojunction-based photodetectors: Characteristics of flexible UV and wavelength-selective detection
Chia-Yun Chen
Department of Materials Science and Engineering, National Cheng Kung University, Taiwan

Abstract
Heterostructures stand for the artificial structures composed of two or more different solid-state materials. When the dimensionality of materials scales down to nanoscale, the interfaces associated with constitute materials play the dominant role on their materials chemistry, materials physics and even being decisive for the correlated device performances. In this talk, two compelling strategies that enable to realize practical photodetection features including flexible UV sensing and wavelength-selective detection, respectively. First, all-carbon based OD/2D heterostuctures on PET substrates that can simulate the capability of converting weak UV irradiation into photo carriers are demonstrated. The integrated devices demonstrate the responsivity of 142.1 A/W, detectivity of 1015 Jones, on/off ratio of 1.73×109, and can sustain the reliable performances after experiencing cycling flexibility test. Next, the facile oxidation treatment for the formation of rational polymer/SiOx/Si nanowire hybrid photodetectors is realized that presents extraordinary wavelength-selective photodetection under light illumination with wavelength of 590 nm. Our findings evidence the existence of surface dipoles at interfaces between polymeric layer and SiOx manifest the modulation of charge-transfer characteristics and account for the effective suppressions of photoresponse under shorter (365 nm) or longer (850 nm) light illuminations. The present photodetector design, along with the mechanism validation was anticipated to be potential for the development of next-generation optoelectronic devices with desired properties.

Biography
Chia-Yun Chen is an Associate Professor in the Department of Materials Science and Engineering at National Cheng Kung University (NCKU). Prior to joining NCKU, he served as an Assistant Professor at National Chi Nan University (NCNU) for two and half years. He received his Ph.D. degree in the Department of Materials Science and Engineering at National Tsing Hua University, and joined Georgia Institute of Technology, USA, as a postdoctoral scholar and visiting research faculty during 2013-2014.
His fields of research interests include functional nanomaterials and devices, materials characterizations, semiconductor processing, solar cells and optical sensing with a focus on their optoelectronic applications. He was the recipient of the Young Scholar Award, MRS-T (2021), Ta-You Wu Memorial Award (2020), Taiwan Vacuum Society Young Scholar Award, TVS (2020), Rising Star Award, NCKU (2018), Special Outstanding Talent Award, MOST (2016), and Outstanding Young Scholar Award, MOST (2014).

Invited Talk 9 [A4] – 10/27 (Fri.) 10:30-10:55

Dr. Yung-Sen Lin 林永森
逢甲大學化學工程學系 特聘教授

Department of Chemical Engineering, Feng Chia University, TAIWAN
Electrochromic Oxide Thin Films Synthesized by Cold Atmospheric Pressure Plasma Polymerization for Flexible Electrochromic Devices
Yung-Sen Lin
Department of Chemical Engineering, Feng Chia University, Taiwan

Abstract
Electrochromic (EC) smart windows are the most attracted smart glazing in buildings for all climatic composition even with their high initial cost. Once cost effective alternative methods can be used to fabricate electrochromic devices (ECDs), EC smart windows will be extensively accepted. EC smart windows can be prepared more reasonably priced and commercially available by using flexible electrochromic devices (FECDs), producing on polymer substrates that can diminish costs with manufacturing via roll-to-roll processes, attaching to lasting windows as a layer and being substituted for full replacement. Cold atmospheric pressure plasma-enhanced chemical vapor deposition (CAP-PECVD) have been frequently investigated to offer an alternative method for thin films deposition due to CAP-PECVD possesses advantages: continuous and easy processes, low equipment costs (by preventing the need of expensive pumping systems), and open system. Cold atmospheric pressure plasma polymerization (CAPPP) is a particular CAP-PECVD that can polymerize thin films at atmospheric pressure even without substrate heating. This talk presents WOxCy thin films have been rapidly deposited onto flexible PET/ITO substrate by co-synthesized with MoOxCy, TaOxCy, FeOxCy and TiOxCy using CAPPP at a simple process for the durations less than 60 s to enhance notable lithium EC properties, such as optical modulation (ΔT%), and switch speeds of coloration and bleaching, and remain supreme flexibility,

Biography
Prof. Yung-Sen Lin received the M.S and Ph.D. degrees in chemical engineering from the University of Missouri–Columbia, Columbia, MO, USA, in1993 and 1996, respectively. He was a Researcher with the Industrial Technology Research Institute, Hsinchu, Taiwan, in 1997, where he was involved in semiconductor package R&D, and a Section Manager with Siliconware Precision Industries Company, Ltd., Taichung, Taiwan, in 1997, where he was involved in development of semiconductor package technology and materials. He was an assistant Professor with the Department of Materials Science and Engineering, I-Shou University, Kaohsiung, Taiwan, in 2000. In 2003, he joined the Department of Chemical Engineering at Feng Chia University, Taichung, where he is currently a Distinguished Professor. His current research interests include Electrochromic thin films and devices, Plasma polymerization, Plasma surface modification, Li+ conducting electrolytes, Semiconductor packaging technology and materials, and Functional coating
Invited Talk 10 [B4] – 10/27 (Fri.) 10:30-10:55

Dr. Tien-Sheng Chao 趙天生
國立陽明交通大學電子物理系 教授

Department of Electrophysics,
National Yang Ming Chiao Tung University, TAIWAN
Hafnium Oxide Based Ferroelectrics for Next Generation Memories
Tien-sheng Chao
Department of Electrophysics, National Yang Ming Chiao Tung University, Taiwan

Abstract
The ferroelectricity based on hafnium oxide has attracted increasing attention since 2011. Memories with hafnium oxide-based show advantages such as CMOS compatibility, matured atomic layer deposition techniques. However, some issues such as the wake-up effect and insufficient endurance are remaining reliability issues. In this paper, the basics and recent research on hafnium oxide-based ferroelectric memory are reviewed. Three types of ferroelectric memories, including ferroelectric RAM (FeRAM), ferroelectric field effect transistors (FeFETs) and ferroelectric tunneling junctions (FTJs), are described and reviewed. Novel processes are proposed to mitigate the wake-up and reliability issues, resulting in improved ferroelectricity and reliability.

Biography
Prof. Tien-Sheng Chao was born in Penghu, Taiwan, in 1963. He received the Ph. D. degrees in Electronics Engineering from National Chiao-Tung University, Hsinchu, Taiwan in 1992. He joined the National Nano Device Laboratories (NDL) as an associate researcher in July, 1992, and became as a researcher in 1996. He was engaged in developing the thin dielectrics preparations, cleaning processes, and CMOS devices fabrication. Then, he joined the Department of Electrophysics, National Yang Ming Chiao Tung University in 2001, and became as a professor from 2002.

Invited Talk 11 [C4] – 10/27 (Fri.) 10:30-10:55

Dr. Po-Wen Chiu 邱博文
國立清華大學電機工程學系 特聘教授

Department of Electrical Engineering, National Tsing Hua University, TAIWAN
Atom-thin 2D electronics: opportunities and challenges
Po-Wen Chiu
Department of Electrical Engineering, National Tsing Hua University, Taiwan

Abstract
Atomically thin transition metal dichalcogenides (TMDs) are layered materials which show exotic electronic properties that differentiate largely from those of conventional bulk semiconductors. Field-effect transistors comprising of TMD channels have been the quest for the transistor era with dimensions close to atomic scale. Certainly, quite a number of technical hurdles remains on the way towards the practical applications of TMD transistors, such as on-site synthesis of n- and p-channels, contact resistivity, mobility fluctuation, defect characterization, post-growth doping, dielectric interfaces, and reliability. In this talk, I will discuss some pressing barriers as we rationally assess the qualification of TMD materials being used as the next-generation transistors. It is important to design contacts such that the transmission is dictated by intrinsic properties of the TMD channel rather than by details of the contacts. Insight into the metal/TMD contacts will be given, with examples showing how the contact barrier can be modulated through the engineering of contact configurations.

Biography
P. W. Chiu received his B.S. and M.S. in materials science from National Tsing Hua University. He studied PhD under the supervision of Prof. Klaus von Klitzing, Nobel laureate in physics for quantum Hall effect, at the Max-Planck Institut für Festkörperforschung in Stuttgart in 2000 and received his degree in Physics at the Technische Universität München (TUM) in 2003. His PhD work was focused on quantum transport in one-dimensional conductor, carbon nanotubes. Upon graduation, he stayed at the Max-Planck Institute for postdoctoral research, exploring spin-dependent electronics using ballistic carbon nanotubes. As motivated by the rise of Mn-doped GaAs diluted magnetic semiconductors, he joined Prof. Hedeo Ohno’s group at the Tohoku University for spintronics. In 2005, he accepted the Assistant Professorship at the Department of Electrical Engineering of National Tsing Hua University. He is now a Distinguished Professor and concurrently the Vice President for research & development at NTHU. His latest research interest spans widely from materials science to fundamental physics and low dimensional electronic devices, with particular focus on the realization of 2D electronic and optoelectronic devices based on graphene and transition metal dichalcogenides..
Invited Talk 12 [D4] – 10/28 (Fri.) 10:30-10:55

Dr. Harry H. L. Kwok 郭漢利 教授

Department of Electrical and Computer Engineering,
University of Victoria, Canada
Carrier Mobility in Pentacene Organic Field-Effect Transistors
Harry H. L. Kwok1, You-Lin Wu2
1Department of Electrical and Computer Engineering, Victoria BC, Canada
2Department of Electrical Engineering, National Chi Nan University, Puli, Nantou, Taiwan

Abstract
Pentacene is one of the more widely studied organic semiconductors used in the making of devices such as the organic field-effect transistor (OFET). While this organic material is well known for its semiconducting properties, the charge transport mechanism in pentacene device is not as well understood. In particular, researchers have found that the hole mobility in pentacene device is rather low, some two orders of magnitude less than the value found in popular materials such as silicon. This is a very important issue as far as electronic devices are concerned as the low hole mobility could translate into very slow devices with low gains. Earlier measurements in the transport properties of pentacene OFETs were mainly done on polycrystalline materials but more recently, the study of single crystal devices are preferred. The rationale appears to be that measurements obtained from single crystal devices would be more reliable. Attention is also directed towards eliminating parasitic and contact resistance. Notwithstanding the efforts, in our opinion, there is generally speaking a lack of agreement regarding the transport mechanism(s) in these devices as well as the appropriate methodology to process and interpret the data. This work focused on the pentacene organic field-effect transistors OFETs and applied the Correlated Disorder Model (CDM) to explain the observed changes in the field-effect mobility at different temperatures and for different biases. A parameter extraction scheme was developed and applied to data reported in the literature. The scheme is capable of reducing the number of fitting parameters to two and offers a better insight into the transport mechanism(s). We examined both single-crystal and polycrystalline pentacene OFETs and achieved satisfactory results. Of the different materials parameters contributing to the value of the field-effect mobility, we identified the localization length, the (hopping) site spacing, and the escape frequency to be most important. It will be through the combined optimization of these parameters that we believe higher values of the field-effect mobility would result. The sensitivity of these parameters to gate bias and structural changes are indicative that further improvements are possible.

Biography
Harry H.L. Kwok obtained his Ph.D. in Electrical Engineering and is currently a Professor and Co-director of the Center for Advanced Materials and Related Technology (CAMTEC). His research interests are in materials, devices, circuits and applications. He has worked with processing technology, ion implantation, thin films, as well as Bipolar, CMOS and GaAs IC design. His recent research include: i) collaboration with researchers at TRIUMF (Tri-University Meson Facility) in the development of high-speed charge-coupled device transient digitizers for the study of kaon decay in EXP787 at Brookhaven National Lab, USA; ii) collaboration with researchers at BCCA (British Columbia Cancer Agency) in the development of an intra-operative ultra compact gamma-ray camera using hybrid multi-pixel hybrid photodiodes (M-HPD) for the study and detection of malignant lymph nodes; iii) development of image sensors (and other types of sensors) and related processing circuits; iv) modeling and development of polymer devices for use in display. The above projects have been supported by NSERC, Micronet (National Center of Excellence), BC Health Research Foundation, and BC Advanced Systems Institute.