Department of Materials Engineering, The University of Tokyo  KITA RESEARCH GROUP
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PUBLICATIONs

Schedules of Presentations at Coming Conferences


... and more to be updated.

Recent Publications & Presentations

< Journals >
  • Jun Koyanagi, Mizuki Nishida, and Koji Kita, “Significant reduction of interface trap density of SiC PMOSFETs by post-oxidation H2O annealing processes with different oxygen partial pressures”, Jpn. J. Appl. Phys. 59, SMMA06 (2020); doi:10.35848/1347-4065/ab8e1f.
  • Takashi Hamaguchi and Koji Kita, “Impacts of density of deposited dielectric films on temperature dependence of interface dipole layer strength in multilayered dielectric capacitors for energy harvesting”, Jpn. J. Appl. Phys. 59, SMMA05 (2020); doi:10.35848/1347-4065/ab8bbe.
  • Qiao Chu, Masato Noborio, Sumera Shimizu, Koji Kita, “Influences of coexisting O2 in H2O-annealing ambient on thermal oxidation kinetics and MOS interface propertieson 4H–SiC (1–100)”, Mater. Sci. Semicond. Proc., 116, 105147 (2020); doi:10.1016/j.mssp.2020.10514.
  • Tae-Hyeon Kil and Koji Kita, “Anomalous band alignment change of SiO2/4H-SiC (0001) and (000-1) MOS capacitors induced by NO-POA and its possible origin”, Appl. Phys. Lett., 116, 122103 (2020); doi:10.1063/1.5135606.
  • Adhi Dwi Hatmanto and Koji Kita, “Physical analysis of remained oxidation byproducts as the origins of lattice distortion at the surface of 4H-SiC by Fourier-transform infrared spectroscopy”, Jpn. J. Appl. Phys., 59, SMMA02 (2020); doi:10.35848/1347-4065/ab7fe9.
  • Koji Kita, Eiki Suzuki, and Qin Mao, “Study on the Effects of Post-Deposition Annealing on SiO2/β-Ga2O3 MOS Characteristics”, ECS Transactions, 92 (1) 59-63 (2019); doi:10.1149/09201.0059ecst.
  • Adhi Dwi Hatmanto and Koji Kita, "Similarity and difference of the impact of ion implantation and thermal oxidation on the lattice structure of 4H-SiC (0001) surface", Appl. Phys. Express, 12, 085507 (2019); doi:10.7567/1882-0786/ab30d4.
  • Adhi Dwi Hatmanto and Koji Kita, "Consideration on kinetics of lattice distortion introduction and lattice relaxation at the surface of thermally-oxidized 4H-SiC (0001)", Appl. Phys. Express, 12, 055505 (2019); doi:10.7567/1882-0786/ab103e.
  • Siri Nittayakasetwat and Koji Kita, "Anomalous temperature dependence
    of Al
    2O3/SiO2 and Y2O3/SiO2 interface dipole layer strengths", J. Appl. Phys., 125, 084105 (2019); doi:10.1063/1.5079926. (Selected for Editor's Pick)
  • H. Hirai and Koji Kita, "Low temperature wet-O2 annealing process for enhancement of inversion channel mobility and suppression of Vfb instability on 4H-SiC (0001) Si-face", Appl. Phys. Lett. 113, 172103 (2018); doi: 10.1063/1.5042038.
  • Koji Kita and Adhi Dwi Hatmanto, "Significant Structural Distortion in the Surface Region of 4H-SiC Induced by Thermal Oxidation and Recovered by Ar Annealing", ECS Trans. 86(12): 63-67 (2018); doi:10.1149/08612.0063ecst.
  • Koji Kita, Mizuki Nishida, Ryota Sakuta, and Hirohisa Hirai, "Minimization of SiO2/4H-SiC (0001) Interface State Densityby Low-Temperature Post-Oxidation-Annealing in Wet Ambient after Nitrogen Passivation" ,ECS Trans. 86(2), 61-65 (2018); doi:10.1149/08602.0061ecst.
  • Adhi Dwi Hatmanto and Koji Kita, "Thermal-oxidation-induced local lattice distortion at surface of 4H-SiC(0001) characterized by in-plane X-ray diffractometry", Appl. Phys. Express 11, 011201 (2018).
  • Mykhailo Pankieiev and Koji Kita, "Effects of oxide replacement with fluoride at the CoFeB interface on interface magnetic anisotropy and its voltage control", AIP Advances 8, 055901 (2018).
  • Hirohisa Hirai and Koji Kita, "Effects of high-temperature diluted-H2 annealing on effective mobility of SiC MOSFETs estimated by split capacitance–voltage technique", Jpn. J. Appl. Phys. 56, 111302 (2017).
  • Koji Kita and Hironobu Kamata, "Demonstration of Large Flatband Voltage Shift by Designing Al2O3/SiO2 Laminated Structures with Multiple Interface Dipole Layers", ECS Transactions, 80 (1) 379-385 (2017).
  • Koji Kita, Hirohisa Hirai, and Kei Ishinoda, "Difference of Near-Interface SiO2 Structures between O2-oxidation and H2O-oxidation of 4H-SiC (0001) and Its Impact on MOS Interface Characteristics", ECS Transactions, 80 (7) 123-128 (2017).
  • Jiayang Fei and Koji Kita, “Opportunity of dipole layer formation at non-SiO2 dielectric interfaces in two cases: Multi-cation systems and multi-anion systems”, Microelectronic Engineering,178, 225-229 (2017).
  • Koji Kita, Hirohisa Hirai, Hiroyuki Kajifusa, Kohei Kuroyama, Kei Ishinoda“Investigation of origins of the critically different MOS interface characteristics between dry-oxidized and wet-oxidized silicon carbide”, Microelectronic Engineering, 178, 186-189 (2017).
  • Jiayang Fei, Ryota Kunugi, Takanobu Watanabe and Koji Kita, “Anomalousflatband voltage shift of AlFxOy/Al2O3 MOS capacitors: A consideration on dipole layer formation at dielectric interfaces with different anions”, Appl. Phys. Lett. 110, 162907 (2017).
  • Hirohisa Hirai and Koji Kita, “Difference of near-interface strain in SiO2 between thermal oxides grown on 4H-SiC by dry-O2 oxidation and H2O oxidation characterized by infrared spectroscopy”, Appl. Phys. Lett. 110, 152104 (2017).
  • Hironobu Kamata and Koji Kita, “Design of Al2O3/SiO2 laminated stacks with multiple interface dipole layers to achieve large flatband voltage shifts of MOS capacitors”, Appl. Phys. Lett.110, 102106 (2017).
  • Y. Fujino and K. Kita, “Estimation of near-interface oxide trap density at SiO2/SiC metal-oxide-semiconductor interfaces by transient capacitance measurements at various temperatures”, J. Appl. Phys. 120, 085710 (2016).
  • Jiayang Fei and Koji Kita, “Understanding the impact of interface reaction on dipole strength at MgO/SiO2 and Y2O3/SiO2 interfaces”, Jpn. J. Appl. Phys. 55, 04EB11 (2016).
  • Kosuke Shimura, Ryota Kunugi, Atsushi Ogura, Shinichi Satoh, Jiayang Fei, Koji Kita and Takanobu Watanabe“Positive and negative dipole layer formation at high-k/SiO2 interfaces simulated by classical molecular dynamics”, Jpn. J. Appl. Phys. 55, 04EB03 (2016).
  • Yuki Fujino and Koji Kita, “Quantitative Characterization of Near-Interface Oxide Traps in 4H-SiC MOS Capacitors by Transient Capacitance Measurements”, ECS Trans, 69 (5) 219-225 (2015).
  • Hirohisa Hirai and Koji Kita, "Suppression of byproduct generation at 4H-SiC/SiO2 interface by the control of oxidation conditions characterized by infrared spectroscopy", Appl. Phys. Express 8, 021401 (2015).
  • Koji Kita, Richard Heihachiro Kikuchi, Hirohisa Hirai, and Yuki Fujino, "Control of 4H-SiC (0001) Thermal Oxidation Process for Reduction of Interface State Density", ECS Trans. 64 (8) 23-28 (2014).
  • Richard Heihachiro Kikuchi and Koji Kita, "Fabrication of SiO2/4H-SiC (0001) Interface with Nearly-Ideal Capacitance-Voltage Characteristics by Thermal Oxidation", Appl. Phys. Lett. 105, 032106 (2014).
  • Koji Kita, Richard Heihachiro Kikuchi, and Hirohisa Hirai, "Understanding of Growth Kinetics of Thermal Oxides on 4H-SiC (0001) for Control of MOS Characteristics", ECS Trans. 61 (2) 135-142 (2014).
  • Richard Heihachiro Kikuchi and Koji Kita, "Interface-reaction-limited growth of thermal oxides on 4H-SiC (0001) in nanometer-thick region", Appl. Phys. Lett. 104, 052106 (2014).
  • Hirohisa Hirai and Koji Kita, "FTIR-ATR Study on Near-Interface Structure of Thermal Oxides on 4H-SiC Substrates", ECS Trans. 58 (7) 317-323 (2013).
  • Jiro Koba and Koji Kita, "Voltage-Induced Nonvolatile Change of Magnetic Anisotropy of CoFeB Ultrathin Films Stacked With Multivalent Oxides", ECS Trans. 58 (5) 127-133 (2013).
  • Hirohisa Hirai and Koji Kita, "Structural difference between near interface oxides grown on Si and C faces of 4H-SiC characterized by infrared spectroscopy", Appl. Phys. Lett. 103, 132106 (2013).
  • W. F. Zhang, T. Nishimula, K. Nagashio, K. Kita, and A. Toriumi, "Conduction Band Offset at GeO2/Ge Interface Determined by Internal Photoemission and Charge-corrected X-ray Photoelectron Spectroscopies", Appl. Phys. Lett. 102, 102106 (2013).
  • Naruto Miyakawa, D. C. Worledge, and Koji Kita, "Impact of Ta Diffusion on the Perpendicular Magnetic Anisotropy of Ta/CoFeB/MgO", IEEE Magnetic Lett. ,4, 1000104 (2013).
  • Yugo Chikata, Koji Kita, Tomonori Nishimura, Kosuke Nagashio, and Akira Toriumi, "Quantitative Characterization of Band-Edge Energy Positions in High-k Dielectrics by X-ray Photoelectron Spectroscopy", Jpn. J. Appl. Phys., 52, 021101 (2013).
  • Koji Kita, David W. Abraham, Martin J. Gajek, and D. C. Worledge, "Electrci-field-control of magnetic anisotropy of Co0.6Fe0.2B0.2/oxide stacks using reduced voltage", J. Appl. Phys., 112, 033919 (2012).
  • Choong Hyun Lee, Tomonori Nishimura, Toshiyuki Tabata, Kosuke Nagashio, Koji Kita, and Akira Toriumi, "Variation of Surface Roughness on Ge Substrate by Cleaning in Deionized Water and its Influence on Electrical Properties in Ge Metal–Oxide–Semiconductor Field-Effect Transistors", Jpn. J. Appl. Phys. 51, 104203 (2012).
  • Shinji Hibino, Tomonori Nishimura, Kosuke Nagashio, Koji Kita, and Akira Toriumi, "Counter Dipole Layer Formation in Multilayer High-k Gate Stacks", Jpn. J. Appl. Phys. 51, 081303 (2012).
< International Conference Presentations >
  • M. Noguchi, T. Iwamatsu, H. Amishiro, H. Watanabe, K. Kita and N. Miura, “Improvement in the Channel Performance and NBTI of SiC-MOSFETs by Oxygen Doping”, 2019 IEEE International Electron Device Meeting (IEDM2019) 20.4 (Dec 2019, San Francisco, CA, USA).
  • Koji Kita, "Consideration on Thermodynamics and Kinetics of SiC Thermal Oxidation in O2 and H2O", 8th International Symposium on Control of Semiconductor Interfaces (ISCSI-VIII), FAI1-2, Nov 29, 2019, Sendai, invited.
  • Munetaka Noguchi, Toshiaki Iwamatsu, Hiroyuki Amishiro, Hiroshi Watanabe, Koji Kita, and Naruhisa Miura, "Improved Channel Characteristics of 4H-SiC MOSFETs by Sulfur Doping Based on the Understanding of Carrier Transport in Inversion Layer", 8th International Symposium on Control of Semiconductor Interfaces (ISCSI-VIII), FA1-1, Nov 29, 2019, Sendai, invited.
  • Qiao Chu, Masato Noborio, Sumera Shimizu and Koji Kita, "Influences of Coexisting O2 in H2O-Annealing Ambient on Thermal Oxidation and MOS Interface Properties on 4H-SiC (1-100)", 8th International Symposium on Control of Semiconductor Interfaces (ISCSI-VIII), FA1-3, Nov 29, 2019, Sendai.
  • Takashi Hamaguchi and Koji Kita, "Difference of Temperature Effects on Al2O3/SiO2 Interface Dipole Layer Strength by SiO2 Growth Methods", 2019 International Workshop on Dielectric Thin Films for Future Electron Devices: Science and Technology (IWDTF2019), S6-3, Nov 20, 2019, Tokyo.
  • Jun Koyanagi and Koji Kita, "Suppression of VFB Instability of p-type 4H-SiC (0001) MOS capacitor by H2O-POA without O2 Introduction", 2019 International Workshop on Dielectric Thin Films for Future Electron Devices: Science and Technology (IWDTF2019), S7-2, Nov 20, 2019, Tokyo.
  • Adhi Dwi Hatmanto and Koji Kita, "Investigation of Thermal Oxidation-induced Lattice Distortion at the Surface of 4H-SiC and Its Origins", 2019 International Workshop on Dielectric Thin Films for Future Electron Devices: Science and Technology (IWDTF2019), S8-2, Nov 20, 2019, Tokyo, Selected for "Best Paper Award".
  • Atsushi Tamura, Masahiro Masunaga, Shintaroh Sato, and Koji Kita, "Study on Leakage Current Conduction Mechanism at high temperature in Al2O3/SiO2/n-type 4H-SiC MOS Capacitors", 2019 International Conference on Silicon Carbide and Related Materials (ICSCRM2019), Tu-P-27, Oct 1, 2019, Kyoto.
  • Jun Koyanagi and Koji Kita, "Improvement of Channel Characteristics of 4H-SiC PMOSFET by Low Temperature Wet-POA with H2-annealing", 2019 International Conference on Silicon Carbide and Related Materials (ICSCRM2019), Mo-P-35, Sep. 30, 2019, Kyoto.
  • Tae-Hyeon Kil and Koji Kita, "Anomalous band alignment change of SiO2/4H-SiC MOS capacitors induced by NO-POA and its possible origin", 2019 International Conference on Silicon Carbide and Related Materials (ICSCRM2019), Mo-2A-01, Sep. 30, 2019, Kyoto.
  • Takashi Hamaguchi and Koji Kita, "Investigation on the Factors to Determine the Efficiency of Energy Harvesting Method with Multilayered Dielectric Capacitors in Temperature Fluctuating Environment", 2019 International Conference on Solid State Devices and Materials (SSDM2019), N-7-04, Sep 5, 2019, Nagoya.
  • Adhi Dwi Hatmanto and Koji Kita, "Investigation of the Possible Origins of Lattice Distortion at the Surface of ThermallyOxidized 4H-SiC (0001) based on the Physical Analysis of Remained Byproducts", 2019 International Conference on Solid State Devices and Materials (SSDM2019), K-6-05, Sep 5, 2019, Nagoya.
  • Koji Kita, Eiki Suzuki, and Qin Mao, "Nearly-Ideal Characteristics of SiO2/β- Ga2O3 MOS Capacitors Fabricated with High-Temperature O2-Annealings", The 3rd International Workshop on Gallium Oxide and Other Related Materials (IWGO-3), Aug 16, 2019, Columbus, OH, USA.
  • Siri Nittayakasetwat and Koji Kita, "Experimentally Observed Temperature-Induced Changes in Interface Dipole Layer  Strengths in high‐k/SiO2 and high‐k/high‐k Systems", 2019 International Conference on Insulating Films on Semiconductors (INFOS2019), July 2, 2019, Cambridge, UK.
  • Tae-Hyeon Kil, Atsushi Tamura and Koji Kita, &quot;Anomalous Change of Band Alignment of SiO2/4H‐SiC (0001) Stacks Induced by the Nitrogen Introduction to The  Interface", 2019 International Conference on Insulating Films on Semiconductors (INFOS2019), July 1, 2019, Cambridge, UK.
  • Koji Kita, "Formation of Interface Dipole Layers between Two Dielectrics: Considerations on Physical Origins and Opportunities to Manipulate Its Strength",
    SEMI Technology Symposium, S2 Advanced Materials & Technologies for Emerging Devices, SEMICON Korea (Jan 23, 2019, Seoul, Korea), invited.
  • M. Noguchi, T. Iwamatsu, H. Amishiro, H. Watanabe, K. Kita and N. Miura, "Channel engineering of 4H-SiC MOSFETs using sulfur as a deep level donor", 2018 IEEE International Electron Device Meeting (IEDM2018) 8.3 (Dec. 3, 2018, San Francisco, CA, USA), in collaboration with Mitsubishi Electric.
  • Eiki Suzuki and Koji Kita, "Impact of O2 Annealing on Chemical State of Ga at SiO2/β-Ga2O3 Interface", 14th International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures / 26th International Colloquium on Scanning Probe Microscopy (ACSIN-14/ICSPM26), 22E15 (Oct. 22, 2018, Sendai).
  • Adhi Dwi Hatmanto and Koji Kita, "Introduction and Recovery of Thermal-oxidation-induced Lattice Distortion at the Surface of 4H-SiC (0001)", 14th International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures / 26th International Colloquium on Scanning Probe Microscopy (ACSIN-14/ICSPM26), 25D14 (Oct. 25, 2018, Sendai).
  • Koji Kita, Mizuki Nishida, Ryota Sakuta, and Hirohisa Hirai, "Minimization of SiO2/4H-SiC (0001) Interface State Density by Low-Temperature Post-Oxidation-Annealing in Wet Ambient after Nitrogen Passivation", 2018 Americas International Meeting on Electrochemistry and Solid State Science (AiMES2018), ECS & SMEQ Joint International Meeting, in Symposium D01 "Semiconductor, Dielectrics, and Metals for Nanoelectronics 16" (Oct. 2, 2018, Cancun, Mexico).
  • Koji Kita and Adhi Dwi Hatmanto, "Significant Structural Distortion in the Surface Region of 4H-SiC Induced By Thermal Oxidation and Recovered By Ar Annealing", 2018 Americas International Meeting on Electrochemistry and Solid State Science (AiMES2018), ECS & SMEQ Joint International Meeting, in Symposium H05 "Gallium Nitride and SIlicon Cabide Power Technologies" (Oct. 3, 2018, Cancun, Mexico).
  • Adhi Dwi Hatmanto and Koji Kita, "Recovery of Local Lattice Distortion at the Surface of Thermally-Oxidized 4H-SiC (0001) by Post-Oxidation Annealing", 2018 International Conference on Solid State Devices and Materials (SSDM2018), D-2-02 (Sep.11, 2018, Tokyo).
  • Mizuki Nishida, Ryota Sakuta, Hirohisa Hirai, and Koji Kita, "Reduction of SiO2/4H-SiC Interface Defects by H2O-PostNitridation-Annealing", 2018 International Conference on Solid State Devices and Materials (SSDM2018), D-2-04 (Sep.11, 2018, Tokyo).
  • Jun Koyanagi, Mizuki Nishida, and Koji Kita, "Significant Improvement of p-type 4H-SiC MOS Interface Characteristics by Low Temperature Post-Oxidation Annealing in H2O + O2 Ambient ", 2018 International Conference on Solid State Devices and Materials (SSDM2018), D-2-05 (Sep.11, 2018, Tokyo).
  • Takashi Hamaguchi, Siri Nittayakasetwat, and Koji Kita, "Study on interface dipole layer strength change by temperature in high-k/SiO2 and high-k/high-k systems and its possible origin ", 2018 International Conference on Solid State Devices and Materials (SSDM2018), B-5-01 (Sep.12, 2018, Tokyo).
  • Siri Nittayakasetwat, and Koji Kita, "Consideration on the effective dipole length in Al2O3/SiO2 and Y2O3/SiO2 interface dipole layers via temperature dependences of their dipole strength ", 2018 International Conference on Solid State Devices and Materials (SSDM2018), PS-1-31(Late News)(Sep.13, 2018, Tokyo).
  • Mizuki Nishida, Ryota Sakuta, Hirohisa Hirai, Koji Kita, "Combination of NO-annealing with H2O-annealing at low temperature to reduce SiO2/4H-SiC (0001) interface defect density", 2018 European Conference on Silicon Carbide and Related Materials (ECSCRM2018), TU.01a.04. (Sep.4, 2018, Birmingham, UK).
  • Adhi Dwi Hatmanto and Koji Kita, "Introduction and recovery of local lattice distortion at the surface of thermally-oxidized 4H-SiC (0001)", 2018 European Conference on Silicon Carbide and Related Materials (ECSCRM2018), WE.02b.02. (Sep.5, 2018, Birmingham, UK).
  • Hironobu Kamata and Koji Kita, "Demonstration of a large Vfb shift induced by selectively formed multiple dipole layers in Al2O3/SiO2 laminated dielectric stacks", 48th IEEE Semiconductor Interface Specialists Conference (SISC2017), 12.1 (Dec. 9, 2017, San Diego, CA, USA).
  • Hirohisa Hirai, Kei Ishinoda and Koji Kita, "Control of thermal oxidation
    of 4H-SiC (0001) to enhance MOSFET channel mobility by tuning partial pressures of oxidants (O
    2 and H2O) and oxidation temperature", 48th IEEE Semiconductor Interface Specialists Conference (SISC2017), 5.17 (Dec. 7, 2017, San Diego, CA, USA).
  • M. Noguchi, T. Iwamatsu, H. Amishiro, H. Watanabe, K. Kita and S. Yamakawa,
    "Determination of intrinsic phonon-limited mobility and carrier transport property extraction of 4H-SiC MOSFETs", 2017 IEEE International Electron Device Meeting (IEDM2017) 9.3, pp. 219-222 (Dec. 4, 2017, San Francisco, CA, USA), in collaboration with Mitsubishi Electric.
  • Ryota Sakuta, Hirohisa Hirai and Koji Kita, "Change of SiO(N) Thermal Growth Kinetics and Element Distribution on 4H-SiC by Foreign Elements (La and N) Introduction", 2017 International Workshop on Dielectric Thin Films for Future Electron Devices (2017 IWDTF), S8-1 (Nov. 22, 2017, Todaiji Temple Cultural Ceter, Nara).
  • Adhi Dwi Hatmanto and Koji Kita, "In-Plane X-ray Diffractometry Study on Thermal Oxidation-induced Anomalous Lattice Distortion at 4H-SiC Surfaces", 2017 International Workshop on Dielectric Thin Films for Future Electron Devices (2017 IWDTF), S8-2 (Nov. 22, 2017, Todaiji Temple Cultural Ceter, Nara).
  • Mizuki Nishida, Hirohisa Hirai and Koji Kita, "Evaluation of Deep Trap and Near-interface Oxide Trap Density at SiO2/SiC Interface by Photo-assisted CV Measurement", 2017 International Workshop on Dielectric Thin Films for Future Electron Devices (2017 IWDTF), S8-4 (Nov. 22, 2017, Todaiji Temple Cultural Ceter, Nara).
  • Siri Nittayakasetwat and Koji Kita, "Temperatures Induced Anomalous Change in Effective Charges of Al2O3/SiO2 Interface Dipole Layer", 2017 International Workshop on Dielectric Thin Films for Future Electron Devices (2017 IWDTF), S5-2 (Nov. 21, 2017, Todaiji Temple Cultural Ceter, Nara).
  • Mykhailo Pankieiev and Koji Kita, "Effect of Fluorine Addition to the Ferromagnetic Interface on the PMA and its Voltage Control", IEEE 62nd Annual Conference on Magnetism and Magnetic Materials (MMM2017), FF-05 (Nov. 9, 2017, Pittsburgh, PA, USA).
  • Koji Kita and Hironobu Kamata, "Demonstration of Large Flatband Voltage Shift by Designing Al2O3/SiO2 Laminated Structures with Multiple Interface Dipole Layers", 232nd The Electrochemical Society (ECS) Meeting, D01-863 (Oct. 6, 2017, National Harbor, MD, USA).
  • Koji Kita, Hirohisa Hirai, and Kei Ishinoda, "Difference of Near-Interface SiO2 Structures between O2-oxidation and H2O-oxidation of 4H-SiC (0001) and Its Impact on MOS Interface Characteristics", 232nd The Electrochemical Society (ECS) Meeting, D01-863 (Oct. 4, 2017, National Harbor, MD, USA).
  • Hirohisa Hirai, Kei Ishinoda and Koji Kita, "Interface-Selective Low-Temperature Wet-O2 Annealing to Enhance 4H-SiC (0001) MOSFET Mobility by Improving Near Interface SiO2 Quality", International Conference on Silicon Carbide and Related Materials (ICSCRM 2017), FR.C1.2 (Sep. 22, 2017, Washington DC,USA).
  • Koji Kita, Hironobu Kamata, and Jiayang Fei, "Interface Dipole Layers between Two Dielectrics: Considerations on Physical Origins and Opportunities to Control Their Formation", 2017 International Conference on Solid State Devices and Materials (SSDM 2017), K-1-01 (Sep. 20, 2017, Sendai International Center,Sendai), invited.
  • Jiayang Fei and Koji Kita, "Consideration on the interfacial dipole layer formation at non-SiO2 oxide interfaces in the examples of MgO/Al2O3 and HfO2/Al2O3", 2017 International Conference on Solid State Devices and Materials (SSDM 2017), K-1-03 (Sep. 20, 2017, Sendai International Center,Sendai).
  • Mykhailo Pankieiev and Koji Kita, "High Electronegativity Element Compounds as Way of Increasing Ferromagnetic Interface PMA and its Voltage Control ", 2017 International Conference on Solid State Devices and Materials (SSDM 2017), PS-12-03 (Sep. 20, 2017, Sendai International Center,Sendai).
  • Kei Ishinoda and Koji Kita, "Kinetics of Enhanced Oxide Growth on 4H-SiC in O2 and H2O Coexisting Ambient", 2017 International Conference on Solid State Devices and Materials (SSDM 2017), O-1-03 (Sep. 20, 2017, Sendai International Center,Sendai).
  • Adhi Dwi Hatmanto and Koji Kita, "Oxidation-induced Lattice Distortion at 4H-SiC (0001) Surface Characterized by Surface Sensitive In-plane X-ray Diffractometry", 2017 International Conference on Solid State Devices and Materials (SSDM 2017), O-1-04 (Sep. 20, 2017, Sendai International Center,Sendai).
  • Jiayang Fei and Koji Kita, "Opportunity of dipole layer formation at non-SiO2 dielectric interfaces in two cases: multi-cation systems and multi-anion systems", 20th Conference on Insulating Films on Semiconductors (INFOS2017) (Jun 29, 2017, Potsdom, Germany).
  • Koji Kita, Hirohisa Hirai, Hiroyuki Kajifusa, Kohei Kuroyama and Kei Ishinoda, "Investigation of Origins of the Critically Different MOS Interface Characteristics between Dry-oxidized and Wet-Oxidized Silicon Carbide", 20th Conference on Insulating Films on Semiconductors (INFOS2017) (Jun 28, 2017, Potsdom, Germany).
  • Weidong Li and Koji Kita, "Enhancement of Interface Anisotropy Energy by Fluoride Introduction at CoFeB/Al2O3 and CoFeB/MgO Interfaces", SPINTECH-IX International School and Conference 2017 (Jun4-8, 2017, Fukuoka International Congress Center, Fukuoka).
  • Koji Kita and Hirohisa Hirai, "Impact of Sacrificial Cosumption of Substrate By Thermal Oxidation on Electron Mobility of 4H-SiC MOSFETs", Pacific Rim Meeting on Electrochemcal and Solid State Science / 230th ECS Meeting, "Symposium G02-Semiconductors, Dielectrics, and Metals for Nanoelectronics 14" (Oct. 5, 2016, Honolulu, HI).
  • Koji Kita, "Opportunities to Design Thermal Oxidation and Post-Oxidation Processes to Control 4H-SiC MOS Interface Characteristics", 2016 Int. Conf. on Solid State Devices and Materials (SSDM), E-3-01 (Sep. 28, 2016, Tsukuba), invited.
  • Hiroyuki Kajifusa and Koji Kita, "Study on the Guideline to Control Dry and Wet Oxidation Conditions to Improve 4H-SiC (000-1) C-face MOS Interface Characteristics," 2016 Int. Conf. on Solid State Devices and Materials (SSDM), E-1-02 (Sep. 27, 2016, Tsukuba).
  • Hirohisa Hirai and Koji Kita,"Impacts on 4H-SiC MOSFET Mobility of High Temperatue Annealing in Oxidizing Or Inert Ambient before Gate Oxide Growth," 2016 Int. Conf. on Solid State Devices and Materials (SSDM), E-1-03 (Sep. 27, 2016, Tsukuba).
  • Hironobu Kamata and Koji Kita,"Design of Al2O3/SiO2 Laminated Stacks with Mutiple Interface Dipole Layers to Induce Large Flatband Voltage Shifts of MOS Capacitors," 2016 Int. Conf. on Solid State Devices and Materials (SSDM), O-1-03 (Sep. 27, 2016, Tsukuba).
  • Jiayang Fei, Ryota Kunugi, Takanobu Watanabe and Koji Kita,"Study on Dipole Layer Formation and its Origin at Al2O3/AlFxOy and Al2O3/AlNxOy Multi-anion Dielectric Interfaces by considering Anion Areal Density and Valence Differences," 2016 Int. Conf. on Solid State Devices and Materials (SSDM), O-1-05 (Sep. 27, 2016, Tsukuba).
  • Koji Kita, Hirohisa Hirai, Yuki Fujino and Hiroyuki Kajifusa, "Control of SiC thermal oxidation processes for the improvement of MOSFET performance", 229th Meeting of the Electrochemical Society, (May 29, 2016, San Diego, CA), invited.
  • Ryusuke Oishi and Koji Kita, "Enhancement of voltage-induced magnetic anisotropy change by preventing ferromagnetic surface oxidation in CoFeB/Al2O3 and CoFeB/ZrO2 stacks", 2016 Joint MMM (Magnetism and Magnetic Materials) -Intermag Conference, EG-09 (Jan 14,2016, San Diego, CA, USA).
  • Jiayang Fei and Koji Kita, "Consideration on the Origin of Dipole Layer Formation at Chemically Reactive and Non-Reactive Oxide/SiO2 Interfaces", 2015 Int. Workshop on Dielectric Thin Films for Future Electron Devices (IWDTF2015) (Nov 2, 2015, Tokyo).
  • Yuki Fujino and Koji Kita, "Quantitative Characterization of Near-Interface Oxide Traps in 4H-SiC MOS Capacitors by Transient Capacitance Measurements", 228th Meeting of the Electrochemical Society (Oct. 12, 2015, Phoenix, USA).
  • Hirohisa Hirai and Koji Kita, "Extraction of electron effective mobility of 4H‐SiC MOS inversion channel with thermally‐grown SiO2 by high‐frequency split C‐V technique", 2015 Int. Conf. on Silicon Carbide and Related Materials (ICSCRM2015) (Oct 6, 2015, Giardini Naxos, Italy).
  • Koji Kita, Richard Heihachiro Kikuchi, and Hirohisa Hirai,"Combination of High‐temperature Oxidation and Low‐temperature O2‐Annealing toward Nearly‐Ideal MOS Characteristics on 4H‐SiC (0001)", 2015 Int. Conf. on Silicon Carbide and Related Materials (ICSCRM2015) (Oct 4, 2015, Giardini Naxos, Italy).
  • Jiayang Fei and Koji Kita, "Understanding on the Impact of Interface Reactions on Dipole Strengths at MgO/SiO2 and Y2O3/SiO2 Interfaces", 2015 Int. Conf. on Solid State Devices and Materials (SSDM2015) (Sep 29, 2015, Sapporo).
  • Yuki Fujino and Koji Kita, "Characterization of Near-Interface Oxide Trap Density in SiC MOS Capacitors by Transient Capacitance Measurements at Various Temperatures", 2015 Int. Conf. on Solid State Devices and Materials (SSDM2015) (Sep 29, 2015, Sapporo).
  • Hiroyuki Kajifusa and Koji Kita, "Removal of Near-Interface Oxide Traps at SiO2/SiC Interface by Post-Oxidation Annealing in Reducing Ambient", 2015 Int. Conf. on Solid State Devices and Materials (SSDM2015) (Sep 29, 2015, Sapporo).
  • Hirohisa Hirai and Koji Kita, "Effects of High-Temperature Diluted-H2 Annealing on Effective Mobility of 4H-SiC MOSFETs with Thermally-Grown SiO2", 2015 Int. Conf. on Solid State Devices and Materials (SSDM2015) (Sep 28, 2015, Sapporo).
  • Hirohisa Hirai and Koji Kita, "Infrared Spectroscopic Study on Near-Interface Structure of THermally-Grown Oxides and Oxidation-Induced Byproducts at 4H-SiC/SiO2 Interface", 45th IEEE Semiconductor Interface Specialists Conference (SISC) (Dec 10, 2014, San Diego, USA).
  • Richard Heihachiro Kikuchi and Koji Kita, "Reduction of Defect State Density at SiO2/SiC Interface Formed by the Thermal Oxidation Accompanied with Direct CO Generation", 2014 Int. Conf. on Solid State Devices and Materials (SSDM2014) (Sep 11, 2014, Tsukuba).
  • Hirohisa Hirai and Koji Kita, "Generation and Suppression of Oxidation Byproducts at 4H-SiC C-face/SiO2 Interface Characterized by Infrared Spectroscopy", 2014 Int. Conf. on Solid State Devices and Materials (SSDM2014) (Sep 10, 2014, Tsukuba).
  • Yuki Fujino, Richard Heihachiro Kikuchi, Hirohisa Hirai and Koji Kita, "Quantitative Characterization of Border Traps with Widely-Spread Time Constant in SiC MOS Capacitors by Transient Capacitance Measurements", 2014 Int. Conf. on Solid State Devices and Materials (SSDM2014) (Sep 10,2014, Tsukuba).
  • Koji Kita, "Achievement of Nearly-Ideal MOS Characteristics on 4H-SiC (0001) Based on Kinetic and Thermodynamic Control of Thermal Oxidation", The 18th Workshop on Dielectrics in Microelectronics (WODIM2014) (Jun 10, 2014, Kinsale, Ireland), invited.
  • Koji Kita, Richard Heihachiro Kikuchi, and Hirohisa Hirai, "Understanding of Growth Kinetics of Thermal Oxides on 4H-SiC (0001) for Control of MOS Characteristics", 225th ECS Meeting (May 12, 2014, Orlando, USA), invited.
  • Richard Heihachiro Kikuchi, Hirohisa Hirai, and Koji Kita, "Understanding of Growth Kinetics and Microscopic Structures of Nanometer-Thick Thermal Oxides on 4H-SiC", International Workship on Dielectric Thin Films for Future Electron Devices: Science and Technology (2013 IWDTF), pp.107-108 (Nov. 8, 2013, Tokyo).
  • Jiro Koba and Koji Kita, "Voltage-Induced Nonvolatile Change of Magnetic Anisotropy of CoFeB Ultrathin Films Stacked With Multivalent Oxides", 224th ECS Meeting, in symposium E5 Nonvolatile Memories 2 (Oct. 31, 2013, San Francisco).
  • Hirohisa Hirai and Koji Kita, "FTIR-ATR Study on Near-Interface Structure of Thermal Oxides on 4H-SiC Substrates", 224th ECS Meeting, in symposium E10 Semiconductors, Dielectrics, and Metals for Nanoelectronics 11 (Oct. 30, 2013, San Francisco).
  • Richard Heihachiro Kikuchi and Koji Kita, "Re-investigation of the Post-oxidation Effects on 4H-SiC MOS Interface with High-Temperature Thermal Oxide", Technical Digest of International Conference on Silicon Carbide and Related Materials (ICSCRM2013), p234 (Oct 2, 2013, Miyazaki).
  • Hirohisa Hirai and Koji Kita, "Structural Difference between Near Interface Oxides Grown on Si and C Faces of 4H-SiC Characterized by FTIR-ATR Method", Technical Digest of International Conference on Silicon Carbide and Related Materials (ICSCRM2013), p114 (Oct 1, 2013, Miyazaki).
  • Jiro Koba and Koji Kita, "Voltage–Induced Nonvolatile Change of Magnetic Anisotropy in TiOx/CoFeB/Ta", Extended Abstracts of the 2013 International Conference on Solid State Devices and Materials (SSDM2013), pp. 802-803 (Sep 25, 2013, Fukuoka).
  • Koji Kita, "Voltage Control of Magnetic Anisotropy of Ferromagnetic/Dielectric Stacks"; Collaborative Conference on Material Research 2013 (CCMR2013)
    (Jun 25, 2013, Jeju, Korea), invited.
  • Naruto Miyakawa, Daniel C. Worledge, and Koji Kita, "Enhanced Voltage Control of Magnetic Anisotropy of Ta/CoFeB/MgO by Suppression of Ta Diffusion and CoFeB Surface Oxidation", 12th Joint MMM/Intermag Conference, BF-02 (Chicago, IL, 1/15/2013).
  • Jiro Koba, Takaho Kuribara, Naruto Miyakawa, and Koji Kita, "Characterization of Voltage Control of Magnetic Anisotropy up to 8 MV/cm by Using Substrate Bias Structure", 12th Joint MMM/Intermag Conference, BF-05 (Chicago, IL, 1/15/2013).
  • Koji Kita and D. C. Worledge, "Challenges and Opportunities in Voltage Control of Magnetic Anisotropy of Ultrathin Ferromagnetic Metals for Future Spintronics",International Conference on Emerging Advanced Nanomaterials (ICEAN2012) (Brisbane, Australia, 10/22/2012), invited.
  • S. Hibino, T. Nishimura, K. Nagashio, K. Kita and A. Toriumi, "Interface Dipole Concellation in SiO2/High-k/SiO2/Si Gate Stacks", 2012 Pacific Rim Meeting on Electrochemical and Solid-State Science (PRiME 2012), (Honolulu, HI, 10/9/2012).
  • W. Zhang, T. Nishimura, K. Nagashio, K. Kita and A. Toriumi, "Conduction Band-offset in GeO2/Ge Stack Determined by Internal Photoemission Spectroscopy", 2012 Pacific Rim Meeting on Electrochemical and Solid-State Science (PRiME 2012), (Honolulu, HI, 10/9/2012).
  • Jiro Koba, Takaho Kuribara, Naruto Miyakawa, and Koji Kita, "Voltage Control of Magnetic Anisotropy of CoFeB Thin Films Stacked with Various Oxides", 2nd Int. Conf. of Asian Union of Manetics Societies (ICAUMS2012), (Nara, 10/05/2012).
  • N. Miyakawa, D. C. Worledge, and K. Kita, "Study on Interface Magnetic Anisotropy Deterioration Mechanisms in Ta/CoFeB/MgO stacks" (Kyoto, Sep. 28, 2012).
  • K. Kita, T. Nishimura, K. Nagashio, and A. Toriumi, "Control of Ge/High-k Interface for Ge CMOS Technology", 39th Conference on the Physics and Chemistry of Surfaces and Interfaces (PCSI-39), we1400 (SantaFe, NM, Jan. 25, 2012), invited.
  • K. Kita, T. Nishimura, K. Nagashio, and A. Toriumi, "Study on Interface Reactions in GeO2/Ge Stacks for Gate Stack Application", 31st Hyoumen-Kagaku-Kai (Annual Meeting of the Surface Science Society of Japan), p.172 (Edokawa-ku, Tokyo, Dec 17, 2011), invited.
  • Koji Kita, D. W. Abraham, M. J. Gajek, and D. C. Worledge, "ElectricElectric-field Induced Change of Magnetic Anisotropy in CoFeB/Oxide Stacks", 56th Conference on Magnetism and Magnetic Materials (MMM)(Scottsdale, AZ, 11/02/2011).
  • K. Kita and A. Toriumi, "Study on Dipole Layer Formation between Two Oxides : Experimental Evidences and Possible Models", 2011 MRS Spring Meeting (San Francisco, CA, 04/27/2011), invited.

    Please also see TORIUMI research group web site for old publications of Prof. Kita.

    Please see the Japanse page for the lists of domestic conference papers.


 
 KITA RESEARCH GROUP The University of Tokyo