Publication

2023

Journal

1. S. Takagi, K. Toprasertpong, Z. Cai, E. Nako, R. Nakane, and Mitsuru Takenaka, “Physical understanding of HfZrO2/Si FeFET memory and its AI applications,” ECS Trans., vol. 112, no. 1, pp. 65–??, 2023 (invited). DOI: 10.1149/11201.0065ecst

2. H. Sakumoto, T. Nakayama, Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Numerical evaluation of bandwidth and optical loss in InP-organic hybrid optical modulator with doping optimization,” Jpn. J. Appl. Phys., vol. 63, 02SP52, 2024. DOI: 10.35848/1347-4065/ad189b

3. S.-Y. Min, K. Toprasertpong, E. Nako, R. Nakane, M. Takenaka, and S. Takagi, “Performance improvement in reservoir computing by using HfZrO2 FeFETs through operating voltage optimization,” Jpn. J. Appl. Phys., vol. 63, 03SP19, 2024. DOI: 10.35848/1347-4065/ad2133

4. K. Toprasertpong, M. Takenaka, and S. Takagi, “Understanding memory window of ferroelectric field-effect transistor under coexistence of charge trapping and ferroelectric polarization: violation of linear superposition,” Jpn. J. Appl. Phys., vol. 63, 02SP47, 2024. DOI: 10.35848/1347-4065/ad15e3

5. Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Design of compact and low-loss S-bends by CMA-ES,” Optics Express, vol. 31, no. 26, pp. 43850– 43863, Dec. 2023. DOI: 10.1364/OE.504866

6. E. Nako, K. Toprasertpong, R. Nakane, M. Takenaka, and S. Takagi, “Reservoir computing system with HZO/Si FeFETs in parallel configuration: Experimental demonstration of speech classification,” IEEE Trans. Electron Devices, vol. 70, no. 11, pp. 5675–5664, Nov. 2023. DOI: 10.1109/TED.2023.3318870

7. R. Tang, K. Watanabe, M. Fujita, H. Tang, T. Akazawa, K. Toprasertpong, S. Takagi, and M. Takenaka, “Non-volatile hybrid optical phase shifter driven by a ferroelectric transistor,” Laser & Photonics Reviews, 2300279, October 2023. DOI: 10.1002/lpor.202300279

8. K. Toprasertpong, C. Matsui, M. Takenaka, K. Takeuchi, and S. Takagi, “Ferroelectric source follower for voltage-sensing nonvolatile memory and computing-in-memory,” Journal of Physics D: Applied Physics, vol. 56, 465103, August 2023. DOI: 10.1088/1361-6463/acee09

9. K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takagi, “Interpretation of mobility universality against effective electric field of Si nMOSFETs based on nonlinear model of surface roughness scattering,” Appl. Phys. Exp., vol. 16, no. 6, 064001, June 2023. DOI: 10.35848/1882-0786/acd6d6

10. C.-T. Chen, X. Han, K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takagi, “Hole Mobility Boosters of (110)-Oriented Extremely Thin Body SiGe-on-Insulator (SGOI) pMOSFETs,” IEEE Trans. Electron Devices, vol. 70, no. 7, pp. 3963–3969, June 2023. DOI: 10.1109/TED.2023.3279306

11. K. Sumita, J. Takayasu, K. Toprasertpong, M. Takenaka, and S. Takagi, “Low specific contact resistance between InAs/Ni–InAs evaluated by multi-sidewall TLM,” AIP Advances, vol. 13, 055310, May 2023. DOI: 10.1063/5.0150296

12. K. Sumita, M.-S. Kang, K. Toprasertpong, M. Takenaka, and S. Takagi, “Formulation of ground states for 2DEG at rough surfaces and application to nonlinear model of surface roughness scattering in nMOSFETs,” IEEE Journal of the Electron Devices Society, vol. 11, pp. 216–229, April 2023. DOI: 10.1109/JEDS.2023.3264814

13. X. Han, C.-T. Chen, M. Ke, Z. Zhao, K. Toprasertpong, M. Takenaka, and S. Takagi, “Effects of post deposition annealing temperature and atmosphere on interface properties in ALD Al2O3/plasma oxidation GeOx/(111) and (100) n-Ge MOS structures,” Jpn. J. Appl. Phys., vol. 62, SC1089, 2023. DOI: 10.35848/1347-4065/acbb89

International conference

1. R. Tang, S. Ohno, K. Tanizawa, K. Ikeda, M. Okano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Inference and training in deep learning using a symmetric optical crossbar array,” Optical Fiber Communication Conference (OFC2024), Tu2F, 24–28 March 2024.

2. S. Takagi, K. Toprasertpong, E. Nako, R. Suzuki, S.-Y. Min, M. Takenaka, and R. Nakane, “Physical reservoir computing using HZO-based FeFETs for edge-AI applications,” International Electron Devices Meeting (IEDM2023), 22.2, San Francisco, 9–13 December 2023 (invited).

3. M. Takenaka, N. Sekine, K. Sumita, H. Sakumoto, S. Fu, K. Toprasertpong, and S. Takagi, “III-V CMOS photonics platform for universal photonics applications,” 4th International Conference on Optics, Photonics, and Lasers (OPL2023), Hiroshima, 4–6 December 2023 (invited).

4. M. Takenaka, “Heterogeneous integration of III-V and phase change material for Si programmable photonic integrated circuits,” 12th International Symposium on Photonics and Electronics Convergence (ISPEC2023), B-4, Tokyo, 1–2 November 2023.

5. T. Akazawa, K. Sumita, S. Monfray, F. Boeuf, K. Toprasertpong, S. Takagi, and M. Takenaka, “Low-loss In-line Optical Power Monitoring using InP/Si hybrid phototransistor,” 13th International Symposium on Photonics and Electronics Convergence (ISPEC2023), P-24, Tokyo, 1–2 November 2023.

6. Y. Miyatake, R. Tang, K. Makino, J. Tominaga, N. Miyata, M. Okano, K. Toprasertpong, S Takagi, and M. Takenaka, “Photonic matrix multiplication with Ge2Sb2Te3S2 intensity modulators,” 13th International Symposium on Photonics and Electronics Convergence (ISPEC2023), P-27, Tokyo, 1–2 November 2023.

7. C. Zhang, Z. Zhao, R. Tang, T. Akazawa, Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Ge avalanche photodiode integrated with microring resonator for 2 µm wavelengths on Ge-on-insulator platform,” 13th International Symposium on Photonics and Electronics Convergence (ISPEC2023), P-33, Tokyo, 1–2 November 2023.

8. R. Tang, S. Ohno, K. Tanizawa, K. Ikeda, M. Okano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Demonstration of inference and training in deep learning using a symmetric silicon microring resonator crossbar array,” 13th International Symposium on Photonics and Electronics Convergence (ISPEC2023), P-25, Tokyo, 1–2 November 2023.

9. M. Fujita, R. Tang, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Memory characteristics of FeFET-driven hybrid MOS optical phase shifter,” 13th International Symposium on Photonics and Electronics Convergence (ISPEC2023), P-3, Tokyo, 1–2 November 2023.

10. Y. Wakita, R. Tang, H. Tang, S. Ohno, T. Akazawa, S. Monfray, F. Boeuf, K. Toprasertpong, S. Takagi, and M. Takenaka, “Demonstration of add-drop ring resonator switch using InGaAsP/Si hybrid MOS phase shifter,” 13th International Symposium on Photonics and Electronics Convergence (ISPEC2023), P-5, Tokyo, 1–2 November 2023.

11. S. Takagi, K. Toprasertpong, Z. Cai, E. Nako, R. Nakane, and M. Takenaka, “Physical understanding of HfZrO2/Si Fefet memory and its AI applications,” 244th ECS Meeting, Symposium G02, Gothenburg, Sweden, 8–12 October 2023 (invited).

12. Y. Maeda, R. Yokogawa, S. Sugawa, C. T. Chen, K. Toprasertpong, M. Takenaka, S. Takagi, and A. Ogura, “Evaluation of anisotropic biaxial stress in extremely thin body (100) SGOI p-MOSFETs By oil-immersion Raman spectroscopy,” 244th ECS Meeting, Symposium G02, Gothenburg, Sweden, 8–12 October 2023.

13. R. Yokogawa, Y. Maeda, S. Sugawa, C. T. Chen, M. Takenaka, S. Takagi, and A. Ogura, “Stress relaxation of extremely-thin-body Ge-on-insulator p-type metal-oxide-semiconductor field-effect transistor along <100> and <110> observed by oil-immersion Raman spectroscopy,” 244th ECS Meeting, Symposium G02, Gothenburg, Sweden, 8–12 October 2023.

14. Y. Miyatake, R. Tang, K. Makino, J. Tominaga, N. Miyata, M. Okano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Photonic tensor core with low-insertion-loss, non-volatile Ge2Sb2Te3S2 intensity modulators,” European Conference on Optical Communication (ECOC2023), Tu.B.3.3, Glasgow, UK, 1–5 October 2023.

15. T. Akazawa, K. Sumita, S. Monfray, F. Boeuf, K. Toprasertpong, S. Takagi, M. Takenaka, “Transparent in-line optical power monitor integrated with MOS optical phase shifter using InP/Si hybrid integration,” European Conference on Optical Communication (ECOC2023), We.D.4.5, Glasgow, UK, 1–5 October 2023.

16. Y. Wakita, R. Tang, H. Tang, S. Ohno, T. Akazawa, Y. Miyatake, S. Monfray, F. Boeuf, K. Toprasertpong, S Takagi, M. Takenaka, “Low-power add-drop microring resonator switch with positive/negative phase tuning using InGaAsP/Si hybrid MOS phase shifter,” European Conference on Optical Communication (ECOC2023), We.D.4.2, Glasgow, UK, 1–5 October 2023.

17. S. Takagi, K. Toprasertpong, E. Nako, R. Suzuki, S.-Y. Min, M. Takenaka, R. Nakane, “Reservoir computing utilizing ferroelectric-gate-insulator FETs and capacitors,” International Conference on Integrated Circuit Design & Technology (ICICDT), Tokyo, Japan, 25–27 September 2023 (invited).

18. H. Sakumoto, T. Nakayama, Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Numerical evaluation of modulation bandwidth and insertion loss in InP-EO polymer hybrid optical modulator with doping optimization,” International Conference on Solid State Devices and Materials (SSDM2023), H-7-04, Nagoya Congress Center, Nagoya, Japan, 5–8 Sept. 2023.

19. K. Toprasertpong, M. Takenaka, and S. Takagi, “Understanding memory window of FeFETs under coexistence of charge trapping and ferroelectric polarization: Violation of linear superposition,” International Conference on Solid State Devices and Materials (SSDM2023), K-1-02, Nagoya Congress Center, Nagoya, Japan, 5–8 Sept. 2023.

20. S. Min, K. Toprasertpong, E. Nako, R. Nakane, M. Takenaka, and S. Takagi, “Improvement in HZO FeFET-based reservoir computing capacities through operating voltage optimization,” International Conference on Solid State Devices and Materials (SSDM2023), K-6-05, Nagoya Congress Center, Nagoya, Japan, 5–8 Sept. 2023 (Late News).

21. M. Takenaka, H. Tang, K. Watanabe, T. Ochiai, T. Akazawa, M. Huang, Y. Wakita, Y. Miyatake, S. Ohno, K. Sumita, S. Monfray, F. Boeuf, R. Tang, K. Toprasertpong, and S. Takagi, “Scalable programmable photonic integrated circuits by III-V/Si hybrid integration,” Optica Advanced Photonics Congress (OAPC), Busan, Korea, 9–13 July 2023 (invited).

22. S. Takagi, M.-S. Kang, K. Toprasertpong, M. Takenaka, H. Oka and T. Mori, “Quantitative understanding of sub-threshold swing of Si MOSFETs at cryogenic temperatures down to 4 K,” 23rd IEEE International Conference on Nanotechnology (IEEE-NANO 2023), Jeju Island, Korea, 2–5 July 2023 (invited).

23. T. Odagawa, K. Sakaino, S. Kimura, T. Inagaki, H. Tang, K. Tanizawa, K. Ikeda, M. Okano, M.  Takenaka, H. Yamada, N. Matsuda, “Demonstration of a low-depth universal linear optical circuit,” CLEO/Europe-EQEC, CK-8.2, Munich, Germany, 26–30 June 2023.

24. Z. Cai, K. Toprasertpong, M. Takenaka, and S. Takagi, “HZO scaling and fatigue recovery in FeFET with low voltage operation: Evidence of transition from interface degradation to ferroelectric fatigue,” VLSI Symposium, T5-2, 11–16 June 2023.

25. M. Takenaka, “Si photonics for optical interconnects,” International Interconnect Technology conference (IITC), Dresden, Germany, 22–25 May 2023 (invited).

26. S. Takagi, K. Toprasertpong, E. Nako, X. Luo, M. Takenaka, and R. Nakane, “HfZrO-based ferroelectric capacitors and FETs for ultralow-power signal processing,” International Conference on Semiconductor Technology for Ultra Large Scale Integrated Circuits and Thin Film Transistors (ULSIC vs. TFT 8), Sapporo, Japan, 15–18 May 2023 (invited).

27. Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Compact Low-loss S-bends Designed by CMA-ES,” Conference on Lasers and Electro-Optics (CLEO2023), SF3E.1, San Jose, USA, 7–12 May 2023.

2022

Journal

14. K. Iwashige, K. Toprasertpong, M. Takenaka, and S. Takagi, “Effect of HfxZr1-xO2/Ge metal-ferroelectrics-insulator-semiconductor interfaces on polarization reversal behavior,” Jpn. J. Appl. Phys., vol. 62, SC1093, 2023. DOI: 10.35848/1347-4065/acb829

15. M. Kang, K. Sumita, H. Oka, T. Mori, K. Toprasertpong, M. Takenaka, and S. Takagi, “Influence of substrate impurity concentration on sub-threshold swing of Si n-channel MOSFETs at cryogenic temperatures down to 4 K,” Jpn. J. Appl. Phys., vol. 62, SC1062, 2023. DOI: 10.35848/1347-4065/acb362

16. R. Yoshizu, K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takagi, “Accurate evaluation of interface trap density at InAs MOS interfaces by using C-V curves at low temperatures,” Jpn. J. Appl. Phys., vol. 62, SC1055. 2023. DOI: 10.35848/1347-4065/acb1bd

17. Y. Miyatake, K. Makino, J. Tominaga, N. Miyata, T. Nakano, M. Okano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Proposal of low-loss non-volatile mid-infrared optical phase shifter based on Ge2Sb2Te3S2,” IEEE Trans. Electron Devices, vol. 70 no. 4, pp. 2106–2112, April 2023. DOI: 10.1109/TED.2023.3235865

18. K. Toprasertpong, M. Takenaka, and S. Takagi, “Breakdown-limited endurance in HZO FeFETs: Mechanism and improvement under bipolar stress,” Frontiers in Electronics, vol. 3, 1091343, 2022. DOI: 10.3389/felec.2022.1091343

19. T. Ochiai, T. Akazawa, Y. Miyatake, K. Sumita, S. Ohno, S. Monfray, F. Boeuf, K. Toprasertpong, S. Takagi, and M. Takenaka, “Ultrahigh-responsivity waveguide-coupled optical power monitor for Si photonic circuits operating at near-infrared wavelengths,” Nature Communications, vol. 13, 7443, 2022. DOI: 10.1038/s41467-022-35206-4

20. K. Toprasertpong, M. Takenaka, and S. Takagi, “On the strong coupling of polarization and charge trapping in HfO2/Si-based ferroelectric field-effect transistors: Overview of device operation and reliability,” Applied Physics A, vol. 128, no. 12, pp. 1114, 2022. DOI: 10.1007/s00339-022-06212-6

21. T. Piyapataraku, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Efficient optical phase modulator based on III–V metal-oxide-semiconductor structure with doped graphene transparent electrode,” Jpn. J. Appl. Phys., vol. 62, SC1008, 2023. DOI: 10.35848/1347-4065/aca59c

22. Y. Miyatake, C.-P. Ho, P. Pitchappa, R. Singh, K. Makino, J. Tominaga, N. Miyata, T. Nakano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Non-volatile compact optical phase shifter based on Ge2Sb2Te5 operating at 2.3 µm,” Opt. Mater. Express, vol. 12, no. 12, pp. 4582–4593, 2022. DOI: 10.1364/OME.473987

23. K. Toprasertpong, K. Tahara, Y. Hikosaka, K. Nakamura, H. Saito, M. Takenaka, and S. Takagi, “Low operating voltage, improved breakdown tolerance, and high endurance in Hf0.5Zr0.5O2 ferroelectric capacitors achieved by thickness scaling down to 4 nm for embedded ferroelectric memory,” ACS Applied Materials & Interface, vol. 14 no. 45, pp. 51137–51148, November 2022. DOI: 10.1021/acsami.2c15369

24. K. Toprasertpong, M. Takenaka, and S. Takagi, “Memory window in ferroelectric field-effect transistors: Analytical approach,” IEEE Trans. Electron Devices, vol. 69 no. 12, pp. 7113–7119, December 2022. DOI: 10.1109/TED.2022.3215667

25. T. Akazawa, D. Wu, K. Sumita, N. Sekine, M. Okano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Low-Capacitance Ultrathin InGaAs Membrane Photodetector on Si Slot Waveguide Toward Receiverless System,” IEEE Trans. Electron Devices, vol. 69 no. 12, pp. 7184–7189, December 2022. DOI: 10.1109/TED.2022.3214797

26. M. Takenaka, Z. Zhao, C.-P. Ho, T. Fujigaki, T. Piyapatarakul, Y. Miyatake, R. Tanga, K. Toprasertpong, and S. Takagi, “Ge-on-insulator Platform for Mid-infrared Photonic Integrated Circuits,” ECS Trans., vol. 109, no. 4, pp. 47–58, 2022 (invited). DOI: 10.1149/10904.0047ecst

27. S. Takagi, C.-T. Chen, X. Han, K. Sumita, K. Toprasertpong, and Mitsuru Takenaka, “Extremely-thin body GOI channel technology in nano-sheet FET era,” ECS Trans., vol. 109, no. 4, pp. 59–71, 2022 (invited). DOI: 10.1149/10904.0059ecst

28. R. Yokogawa, C. -T. Chen, K. Toprasertpong, M. Takenaka, S. Takagi, and A. Ogura, “Evaluation of Strained Group IV Semiconductor Devices by Oil-Immersion Raman Spectroscopy,” ECS Trans., vol. 109, no. 4, pp. 351–357, 2022 (invited). DOI: 10.1149/10904.0351ecst

29. R. Tang, M. Okano, K. Toprasertpong, S. Takagi, D. Englund, and M. Takenaka, “Two-layer integrated photonic architectures with multiport photodetectors for high-fidelity and energy-efficient matrix multiplications,” Optics Express, vol. 30, no. 19, pp. 33940–33954, Sep. 2022. DOI: 10.1364/OE.457258

30. K. Toprasertpong, E. Nako, Z. Wang, R. Nakane, M. Takenaka, and S. Takagi, “Reservoir computing on a silicon platform with a ferroelectric field-effect transistor,” Communications Engineering, vol. 1, 21, August 2022. DOI: 10.1038/s44172-022-00021-8

31. S. Ohno, R. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Si Microring Resonator Crossbar Array for On-Chip Inference and Training of the Optical Neural Network,” ACS Photonics, vol. 9, no. 8, pp. 2614– 2622, July 2022. DOI: 10.1021/acsphotonics.1c01777

32. N. Sekine, K. Sumita, K. Toprasertpong, S. Takagi, and M. Takenaka, “Monolithic integration of electro-absorption modulators and photodetectors on III-V CMOS photonics platform by quantum well intermixing,” Optics Express, vol. 30, no. 13, pp. 23318– 23329, June 2022. DOI: 10.1364/OE.462626

33. H. Tang, Q. Li, C.-P. Ho, J. Fujikata, M. Noguchi, S. Takahashi, K. Toprasertpong, S. Takagi, and M. Takenaka, “Modulation bandwidth improvement of III-V/Si hybrid MOS optical modulator by reducing parasitic capacitance,” Optics Express, vol. 30, no. 13, pp. 22848– 22859, June 2022. DOI: 10.1364/OE.457444

34. M. Yokoyama, H. Yokoyama, M. Takenaka, and S. Takagi, “Characterization of interface properties of Al2O3/n-GaSb and Al2O3/InAs/n-GaSb metal-oxide-semiconductor structures,” Jpn. J. Appl. Phys., vol. 61, 061010, 2022. DOI: 10.35848/1347-4065/ac66b0 

International conference

28. S. Takagi, K. Toprasertpong, E. Nako, M. Takenaka, and R. Nakane, “Hafnia-based ferroelectric devices for lower power memory and AI applications,” Electron Devices Technology and Manufacturing Conference (EDTM2023), 10C-1, Seoul, Korea, 7–10 March 2023 (invited).

29. S. Takagi, K. Sumita, C.-T. Chen, X. Han, K. Toprasertpong, and M. Takenaka, “Superiority of extremely-thin body GOI channels in nano-sheet MOSFETs,” 13th International Workshop on New Group IV Semiconductor Nanoelectronics, I-12, Sendai, 23–24 January 2023 (invited).

30. Y. Miyatake, K. Makino, J. Tominaga, N. Miyata, T. Nakano, M. Okano, K. Toprasertpong, S. Takagi, M. Takenaka, “Record-low loss non-volatile mid-infrared PCM optical phase shifter based on Ge2Sb2Te3S2,” International Electron Devices Meeting (IEDM2022), 19.1, San Francisco, 3–7 December 2022.

31. M. Takenaka, T. Ochiai, T. Akazawa, Y. Miyatake, K. Sumita, S. Ohno, S. Monfray, F. Boeuf, K. Toprasertpong, and S. Takagi, “Si hybrid integration using ultrathin III-V membrane for photodetection,” 12th International Symposium on Photonics and Electronics Convergence (ISPEC2022), D-2, Tokyo, 1–2 December 2022.

32. T. Piyapatarakul, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Design of the III-V MOS optical modulator with doped graphene electrode for efficient, high-speed phase modulation,” 12th International Symposium on Photonics and Electronics Convergence (ISPEC2022), P-1, Tokyo, 1–2 December 2022.

33. Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Optimization of Compact and Low-loss 2×2 Si Optical Coupler based on CMA-ES,” 12th International Symposium on Photonics and Electronics Convergence (ISPEC2022), P-2, Tokyo, 1–2 December 2022.

34. C. Zhang, Z. Zhao, K. Toprasertpong, S. Takagi, and M. Takenaka, “Sub-bandgap photodetection at mid-infrared wavelengths using Ge Micro-ring resonator on Ge-on-insulator platform,” 12th International Symposium on Photonics and Electronics Convergence (ISPEC2022), P-4, Tokyo, 1–2 December 2022.

35. R. Tang, M. Okano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Two-layer integrated photonic architectures for matrix-vector and matrix-matrix multiplications,” 12th International Symposium on Photonics and Electronics Convergence (ISPEC2022), P-5, Tokyo, 1–2 December 2022.

36. T. Akazawa, D. Wu, K. Sumita, N. Sekine, M. Okano, K. Toprasertpong, S. Takagi, and M. Takenaka, “Low-capacitance InGaAs/Si Waveguide Photodetector for Energy-efficient Receiver System,” 12th International Symposium on Photonics and Electronics Convergence (ISPEC2022), P-26, Tokyo, 1–2 December 2022.

37. M. Takenaka, Z. Zhao, T. Piyapatarakul, Y. Miyatake, K. Toprasertpong, and S. Takagi, “Ge-on-insulator platform for mid-infrared photonic integrated circuits,” 242th ECS Meeting, Symposium G03, Hilton Atlanta, Atlanta, USA, 9–13 October 2022 (invited).

38. T. Fukui, K. Sumita, M. Takenaka, S. Takagi, Y. Nakano, T. Tanemura, “Numerical investigation of high-speed surface-normal modulator using InP high-contrast grating,” 28th IEEE International Semiconductor Laser Conference (ISLC 2022), TuP-40, Kunibiki Messe, Japan, 16–19 October 2022.

39. S. Takagi, C. T. Chen, X. Han, K. Sumita, K. Toprasertpong, and M. Takenaka, “Extremely-thin body GOI channel technology in nano-sheet FET era,” 242th ECS Meeting, Symposium G03, Hilton Atlanta, Atlanta, USA, 9–13 October 2022 (invited).

40. T. Piyapataraku, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Analysis of III-V MOS optical modulator with transparent doped graphene gate electrode,” International Conference on Solid State Devices and Materials (SSDM2022), A-2-03, Makuhari Messe, Japan, 26–29 Sept. 2022.

41. T. Nakayama, K. Toprasertpong, S. Takagi, and M. Takenaka, “Investigation of Au-InGaAs Alloy for plasmonic InGaAs waveguide photodetector,” International Conference on Solid State Devices and Materials (SSDM2022), A-9-04, Makuhari Messe, Japan, 26–29 Sept. 2022.

42. Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Compact, low-loss, fabrication-tolerant, and thermally stable 2x2 Si optical coupler designed by CMA-ES,” International Conference on Solid State Devices and Materials (SSDM2022), A-10-04, Makuhari Messe, Japan, 26–29 Sept. 2022.

43. K. Toprasertpong, E. Nako, Z. Wang, R. Nakane, M. Takenaka, and S. Takagi, “FeFET reservoir with four-terminal operation for efficient and flexible reservoir computing hardware,” International Conference on Solid State Devices and Materials (SSDM2022), F-7-03, Makuhari Messe, Japan, 26–29 Sept. 2022.

44. M.-S. Kang, K. Sumita, H. Oka, T. Mori, K. Toprasertpong, M. Takenaka, and S. Takagi, “Substrate impurity concentration dependence of sub-threshold swing of Si n-channel MOSFETs at cryogenic temperatures down to 4 K,” International Conference on Solid State Devices and Materials (SSDM2022), G-1-01, Makuhari Messe, Japan, 26–29 Sept. 2022.

45. K. Sumita, M.-S. Kang, K. Toprasertpong, M. Takenaka, and S. Takagi, “Accurate evaluation of interface trap density at InAs MOS interfaces by using C-V characteristics at low temperatures,” International Conference on Solid State Devices and Materials (SSDM2022), G-1-02, Makuhari Messe, Japan, 26–29 Sept. 2022.

46. R. Yoshizu, K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takagi, “Electron mobility of Si nMOSFETs in a nonlinear model of surface roughness scattering at cryogenic temperature,” International Conference on Solid State Devices and Materials (SSDM2022), G-1-04, Makuhari Messe, Japan, 26–29 Sept. 2022.

47. X. Luo, K. Toprasertpong, M. Takenaka, and S. Takagi, “ZrO2/Si gate stack for antiferroelectric MFIS capacitors and antiferroelectric Si n-FETs,” International Conference on Solid State Devices and Materials (SSDM2022), G-6-06, Makuhari Messe, Japan, 26–29 Sept. 2022.

48. C.-T. Chen, X. Han, K. Toprasertpong, M. Takenaka, and S. Takagi, “Mobility enhancement in extremely-thin body (110) SiGe-on-insulator pMOSFETs using starting substrates with thin SiGe layers,” International Conference on Solid State Devices and Materials (SSDM2022), G-7-02, Makuhari Messe, Japan, 26–29 Sept. 2022.

49. K. Iwashige, K. Toprasertpong, M. Takenaka, and S. Takagi, “Effects of HfxZr1-xO2 Ferroelectrics/Ge MFIS interfaces on polarization reversal behavior,” International Conference on Solid State Devices and Materials (SSDM2022), G-8-02, Makuhari Messe, Japan, 26–29 Sept. 2022.

50. X. Han, C.-T. Chen, M. Ke, Z. Zhao, K. Toprasertpong, M. Takenaka, and S. Takagi, “Impacts of annealing temperature and atmosphere on (111) and (100) n-Ge MOS interface properties with plasma oxidation GeOx and ALD Al2O3,” International Conference on Solid State Devices and Materials (SSDM2022), G-10-04, Makuhari Messe, Japan, 26–29 Sept. 2022.

51. H. Tang., R. Tang, J. Fujikata, M. Noguchi, S. Takahashi, K. Toprasertpong, S. Takagi, and M. Takenaka, “Crossbar wiring for III-V/Si MOS optical phase shifters with diode selectors,” European Conference on Optical Communication (ECOC2022), We4E.4, Basel, Switzerland, 18–22 September 2022.

52. M. Takenaka, H. Tang, K. Watanabe, T. Ochiai, T. Akazawa, Y. Miyatake, S. Ohno, K. Sumita, S. Monfray, F. Boeuf, R. Tang, K. Toprasertpong, and S. Takagi, “III-V/Si hybrid integration for scalable optical switching and computing,” International Conference on Photonics in Switching and Computing (PSC2022), Toyama, 3–7 July 2022 (invited).

53. T. Akazawa, D. Wu, K. Sumita, N. Sekine, M. Okano, K. Toprasertpong, S. Takagi and M. Takenaka, “Low-capacitance ultrathin InGaAs membrane photodetector on Si slot waveguide towards receiver-less system,” VLSI Symposium, T15-4, 12–17 June 2022.

54. E. Nako, K. Toprasertpong, R. Nakane, M. Takenaka, and S. Takagi, “Experimental demonstration of novel scheme of HZO/Si FeFET reservoir computing with parallel data processing for speech recognition,” VLSI Symposium, C25-1, 12–17 June 2022.

55. F. Boeuf, S. Monfray, C. Barrera, A. Fincato, H. Tang, S. Guerber, S. Ohno, D. Fowler, I. Charlet, L. Maggi, M. Shaw, K. Toprasertpong, S. Takagi, and M. Takenaka, “Beyond interconnects applications using a 300mm silicon photonics technology,” European Conference on Integrated Optics (ECIO2022), F.C.1, Milan, Italy, 4–6 May 2022 (invited). 

2021

Journal

35. K. Sumita, C.-T. Chen, K. Toprasertpong, M. Takenaka, S. Takagi, “Optimum channel design of extremely-thin-body nMOSFETs utilizing anisotropic valley--Robust to surface roughness scattering,” IEEE Trans. Electron Devices, vol. 69 no. 4, pp. 2115–2121, 2022. DOI: 10.1109/TED.2022.3143484

36. X. Han, C.-T. Chen, C.-M. Lim, K. Toprasertpong, M. Takenaka, and S. Takagi, “Introduction of high tensile strain into Ge-on-Insulator structures by oxidation and annealing at high temperature,” Jpn. J. Appl. Phys., vol. 61, SC1027, 2022. DOI: 10.35848/1347-4065/ac4075

37. T. Piyapataraku, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Numerical analysis of optical phase modulator operating at 2 μm wavelength using graphene/III-V hybrid metal-oxide-semiconductor capacitor,” Jpn. J. Appl. Phys., vol. 61, SC1031, Feb. 2022. DOI: 10.35848/1347-4065/ac4443

38. M.-S. Kang, K. Toprasertpong, M. Takenaka, H. Oka, T. Mori, and S. Takagi, “Verification of influence of tail states and interface states on sub-threshold swing of Si n-channel MOSFETs over a temperature range of 4–300 K,” Jpn. J. Appl. Phys., vol. 61, SC1032, Feb. 2022. DOI: 10.35848/1347-4065/ac4444

39. R. Nur, T. Tsuchiya, K. Toprasertpong, K. Terabe, S. Takagi, and M. Takenaka, “Floating gate negative capacitance MoS2 phototransistor with high photosensitivity,” Nanoscale, vol. 14, pp. 2013–2022, Jan. 2022. DOI: 10.1039/D1NR06315D

40. C.-T. Chen, K. Sumita, K. Toprasertpong, M. Takenaka, S. Takagi, “Effective mobility enhancement through asymmetric strain channels on extremely thin body (100) GOI pMOSFETs,” IEEE Trans. Electron Devices, vol. 69, no. 1, pp. 25–30, 2021. DOI: 10.1109/TED.2021.3130221

41. Z. Zhao, C.-M. Lim, C. Ho, K. Sumita, Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Low-loss Ge waveguide at the 2-µm band on an n-type Ge-on-insulator wafer,” Opt. Mater. Express, vol. 11, no. 12, pp. 4097–4106, 2021. DOI: 10.1364/OME.444071

42. S. Takagi, K. Toprasertpong, K. Tahara, E. Nako, R. Nakane, Z. Wang, X. Luo, T.-E. Lee, and M. Takenaka, “HfZrO-based ferroelectric devices for low power AI and memory applications,” ECS Trans., vol. 104, no. 4, pp. 17–26, 2021 (invited). DOI: 10.1149/10404.0017ecst

43. K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takagi, “Evaluation of interface traps inside the conduction band of InAs-on-insulator nMOSFET by self-consistent Hall-QSCV method,” Appl. Phys. Lett., vol. 119, 103501, 2021. DOI: 10.1063/5.0057182

44. T.-E. Lee, K. Toprasertpong, M. Takenaka, and S. Takagi, “Re-examination of effects of ALD high-k materials on defect reduction in SiGe metal–oxide–semiconductor interfaces,” AIP Advances, vol. 11, 085021, August 2021. DOI: 10.1063/5.0061573

45. T.-E. Lee, K. Toprasertpong, M. Takenaka, and S. Takagi, “Impacts of equivalent oxide thickness scaling of TiN/Y2O3 gate stacks with trimethylaluminum treatment on SiGe MOS interface properties,” IEEE Electron Dev., vol. 42, no. 7, pp. 966–969, July 2021. DOI: 10.1109/LED.2021.3081513

46. X. Luo, K. Toprasertpong, M. Takenaka, and S. Takagi, “Antiferroelectric properties of ZrO2 ultra-thin films prepared by atomic layer deposition,” Appl. Phys. Lett., vol. 118, 232904, 2021. DOI: 10.1063/5.0051068

47. C.-H. Lim, Z. Zhao, K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takagi, “Electrical properties of ultra-thin body (111) Ge-on-insulator n-channel MOSFETs fabricated by smart-cut process,” IEEE Journal of the Electron Devices Society, vol. 9, pp. 612–617, June 2021. DOI: 10.1109/JEDS.2021.3085981

International conference

56. M. Takenaka, N. Sekine, K. Toprasertpong, and S. Takagi, “III-V CMOS photonics platform based on quantum well intermixing,” 11th International Symposium on Photonics and Electronics Convergence (ISPEC2021), G-4, Tokyo, 13–15 December 2021.

57. T. Piyapatarakul, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Computational analysis of optical phase modulation using graphene/III-V hybrid MOS capacitor,” 11th International Symposium on Photonics and Electronics Convergence (ISPEC2021), P-16, Tokyo, 13–15 December 2021.

58. Y. Miyatake, C.-P. Ho, K. Makino, J. Tominaga, N. Miyata, T. Nakano, N. Sekine, K. Toprasertpong, S. Takagi, and M. Takenaka, “Reduction of optical loss of phase-change phase shifter based on Ge2Sb2Te5 operating at mid-infrared wavelength,” 11th International Symposium on Photonics and Electronics Convergence (ISPEC2021), P-22, Tokyo, 13–15 December 2021.

59. T. Akazawa, K. Sumita, S. Monfray, F. Boeuf, K. Toprasertpong, S. Takagi, and M. Takenaka, “Infrared photodetection using ultrathin InP MSM structure on Si waveguide,” 11th International Symposium on Photonics and Electronics Convergence (ISPEC2021), P-11, Tokyo, 13–15 December 2021.

60. K. Watanabe, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Non-volatility of hybrid MOS optical phase shifter using Si FeFET,” 11th International Symposium on Photonics and Electronics Convergence (ISPEC2021), P-36, Tokyo, 13–15 December 2021.

61. R. Tang, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Robust Optimization of Programmable Unitary Optical Processors,” 11th International Symposium on Photonics and Electronics Convergence (ISPEC2021), P-02, Tokyo, 13–15 December 2021.

62. H. Tang, R. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Numerical analysis of distributed slab capacitance in III-V/Si hybrid MOS phase shifter,” 11th International Symposium on Photonics and Electronics Convergence (ISPEC2021), P-17, Tokyo, 13–15 December 2021.

63. F. Boeuf, C. Barrera, A. Fincato, H. Tang, S. Guerber, S. Monfray, S. Ohno, D. Fowler, I. Charlet, L. Gianini, A. Simbula, L. Maggi, M. Shaw, K. Toprasertpong, S. Takagi and M. Takenaka, “Silicon photonics beyond optical interconnects,” International Electron Devices Meeting (IEDM2021), 29.2, San Francisco, 11–15 December 2021.

64. K. Sumita, C.-T. Chen, K. Toprasertpong, M. Takenaka, and S. Takagi, “Optimum design of channel material and surface orientation for extremely-thin-body nMOSFETs under new modeling of surface roughness scattering,” International Electron Devices Meeting (IEDM2021), 18.3, San Francisco, 11–15 December 2021.

65. R. Nur, T. Tsuchiya, K. Toprasertpong, K. Terabe, S. Takagi, and M. Takenaka, “Ferroelectric HfO2-based monolayer MoS2 optical synaptic transistor for neuromorphic vision systems,” 4th International Conference on Memristive Materials, Devices and Systems (MEMRISYS2021), 4A-4, Tsukuba, Japan, 1–4 November 2021.

66. M. Takenaka, K. Toprasertpong, and S. Takagi, “Materials drive Si photonics,” 34th International Microprocesses and Nanotechnology Conference (MNC2021), virtual, 26–29 October 2021 (keynote).

67. K. Toprasertpong, E. Nako, Z. Wang, C. Matsui, R. Nakane, K. Takeuchi, M. Takenaka, and S. Takagi, “HfZrO2-based ferroelectric FETs for emerging computing technologies,” International Workshop on Dielectric Thin Films for Future Electron Devices: Science and Technology (IWDTF2021), S7-1, virtual, 14–16 November, 2021 (invited).

68. S. Takagi, K. Toprasertpong, K. Tahara, E. Nakoh, R. Nakane, Z. Wang, X. Luo, T. E. Lee, and M. Takenaka, “HfZrO-Based ferroelectric devices for lower power AI and memory applications,” 240th ECS Meeting, Symposium G02, Orlando, Florida, USA, 13–17 October 2021 (invited).

69. Z. Zhao, C.-P. Ho, Q. Li, K. Toprasertpong, S. Takagi, and M. Takenaka, “Ge ring modulator based on carrier-injection phaser shifter operating at two micrometer band,” European Conference on Optical Communication (ECOC2021), Tu4D-4, Bordeaux, France, 13–16 September 2021.

70. T. Piyapataraku, H. Tang, K. Toprasertpong, S. Takagi, and M. Takenaka, “Design of efficient low-loss graphene/InGaAsP hybrid MOS optical phase modulator operating at 2µm wavelength,” International Conference on Solid State Devices and Materials (SSDM), E-6-02, virtual, 7–9 Sept. 2021.

71. M.-S. Kang, K. Toprasertpong, M. Takenaka, S. Takagi, “Characterization of Sub-threshold Swing of Si n-MOSFETs over a Temperature Range of 4 K to 300 K,” International Conference on Solid State Devices and Materials (SSDM), A-1-03, virtual, 7–9 Sept. 2021.

72. X. Han, C.-T. Chen, C.-M. Lim, K. Toprasertpong, M. Takenaka, and S. Takagi, “Introduction of high tensile strain in Ge-on-Insulator structures by oxidation/annealing at high temperature,” International Conference on Solid State Devices and Materials (SSDM), A-4-02, virtual, 7–9 Sept. 2021.

73. R. Yokogawa, C.-T. Chen, K. Toprasertpong, M. Takenaka, S. Takagi, A. Ogura, “Anisotropic strain states in extremely-thin body Ge-on-insulator p-type MOSFET observed by oil-immersion raman spectroscopy,” International Conference on Solid State Devices and Materials (SSDM), A-4-03, virtual, 7–9 Sept. 2021.

74. K. Toprasertpong, M. Takenaka, and S. Takagi, “Four-terminal polarization-voltage measurement technique for analyzing polarization characteristics of ferroelectric FETs,” International Conference on Solid State Devices and Materials (SSDM), B-3-03, virtual, 7–9 Sept. 2021.

75. Z. Wang, E. Nako, K. Toprasertpong, R. Nakane, M. Takenaka, and S. Takagi, “Improvement in computing capabilities of FeFET-based reservoir computing by using an inverted signal scheme,” International Conference on Solid State Devices and Materials (SSDM), B-3-04, virtual, 7–9 Sept. 2021.

76. E. Nako, K. Toprasertpong, R. Nakane, Z. Wang, M. Takenaka, S. Takagi, “Impact of endurance characteristics of FeFETs on reservoir computing capabilities,” International Conference on Solid State Devices and Materials (SSDM), B-5-07, virtual, 7–9 Sept. 2021.

77. X. Luo, K. Toprasertpong, M. Takenaka, and S. Takagi, “Antiferroelectric properties of ALD ZrO2 ultra-thin films: correlation with the crystalline structure,” International Conference on Solid State Devices and Materials (SSDM), A-5-03, virtual, 7–9 Sept. 2021.

78. T.-E. Lee, S.-T. Huang, C.-Y. Yang, K. Toprasertpong, M. Takenaka, Y.-J. Lee, and S. Takagi, “Improvement of performance of Si0.8Ge0.2/SOI p-FinFETs by ultrathin Y2O3 gate stacks with TMA treatment,” International Conference on Solid State Devices and Materials (SSDM), A-7-05, virtual, 7–9 Sept. 2021.

79. C.-T. Chen, R. Yokogawa, K. Toprasertpong, A. Ogura, M. Takenaka, and S. Takagi, “Impact of asymmetric strain on performance of extremely-thin body (100) GOI and (110) SGOI pMOSFETs,” VLSI Symposium, T3-4, 13–19 June 2021.

80. N. Sekine, K. Toprasertpong, S. Takagi and M. Takenaka, “Bandgap-tunable III-V-OI photonics platform with quantum well intermixing for versatile active-passive integration of chip-scale photonic integrated circuits,” VLSI Symposium, JFS3-6, 13–19 June 2021.

81. K. Tahara, K. Toprasertpong, Y. Hikosaka, K. Nakamura, H. Saito, M. Takenaka, and S. Takagi, “Strategy toward HZO BEOL-FeRAM with low-voltage operation (≤ 1.2 V), low process temperature, and high endurance by thickness scaling,” VLSI Symposium, T7-3, 13–19 June 2021.

82. S. Ohno, S. Monfray, F. Boeuf, K. Toprasertpong, S. Takagi, and M. Takenaka, “Monolithic integration of III-V/Si hybrid MOS optical phase shifter and InGaAs membrane photodetector,” Optical Fiber Communication Conference (OFC2021), F2C.1, 6–11 June 2021.

83. H. Tang, S. Ohno, Y. Miyatake, K. Toprasertpong, S. Takagi, and M. Takenaka, “Thermo-optic Mach–Zehnder interferometer integrated with Si PN diode switch for bipolar optical phase control,” Optical Fiber Communication Conference (OFC2021), Tu5B.5, 6–11 June 2021.

84. S. Takagi, K. Kato, and M. Takenaka, “Bilayer Tunneling Field Effect Transistors using Oxide Semiconductor/Group-IV Semiconductor Hetero-structures,” Display Week, 7-5, virtual, 16–21 May 2021 (invited).

85. M. Takenaka, Z. Zhao, C.-P. Ho, T. Fujigaki, K. Toprasertpong, and S. Takagi, “Germanium mid-infrared integrated photonics on GeOI platform,” Conference on Lasers and Electro-Optics (CLEO2021), SM3J.3, 9–14 May 2021 (invited).

2020

Journal

1. Q. Li, C. P. Ho, H. Tang, M. Okano, K. Ikeda, S. Takagi, and M. Takenaka, “Si racetrack optical modulator based on the III–V/Si hybrid MOS capacitor,” Optics Express, vol. 29, no. 5, pp. 6824–6833, March 2021. DOI: 10.1364/OE.418108

2. K. Sumita, K. Toprasertpon, M. Takenaka, and S. Takagi, “Proposal and experimental demonstration of ultrathin-body (111) InAs-on-insulator nMOSFETs with L valley conduction,” IEEE Trans. Electron Devices, vol. 68, no. 4, pp. 2003–2009, January 2021. DOI: 10.1109/TED.2021.3049455

3. R. Nur, T. Tsuchiya, K. Toprasertpon, K. Terabe, S. Takagi, and M. Takenaka, “High responsivity in MoS2 phototransistors based on charge trapping HfO2 dielectrics,” Communications Materials, vol. 1, 103, Dec. 2020. DOI: 10.1038/s43246-020-00103-0

4. M. Mitsuhara, T. Gotow, T. Hoshi, H. Sugiyama, M. Takenaka, and S. Takagi, “Comparative studies of structural and photoluminescence properties between tensile-strained In0.39Ga0.61As and GaAs0.64Sb0.36 layers grown on InP (001) substrates,” J. Crystal Growth, vol.555, 125970, Feb. 2021. DOI: 10.1016/j.jcrysgro.2020.125970

5. S. Ohno, Q. Li, N. Sekine, J. Fujikata, M. Noguchi, S. Takahashi, K. Toprasertpong, S. Takagi, and M. Takenaka, “Taperless Si hybrid optical phase shifter based on a metal-oxide-semiconductor capacitor using an ultrathin InP membrane,” Optics Express, vol. 28, no. 24, pp. 35663– 35673, Nov. 2020. DOI: 10.1364/OE.405038

6. K. Toprasertpong, K. Tahara, T. Fukui, Z. Lin, K. Watanabe, M. Takenaka, and S. Takagi, “Improved ferroelectric/semiconductor interface properties in Hf0.5Zr0.5O2 ferroelectric FETs by low-temperature annealing,” IEEE Electron Dev., vol. 41, no. 10, pp. 1588 – 1591, 2020. DOI: 10.1109/LED.2020.3019265

7. T.-E. Lee, M. Ke, K. Toprasertpong, M. Takenaka and S. Takagi, “Reduction of MOS interface defects in TiN/Y2O3/Si0.78Ge0.22 structures by trimethylaluminum treatment,” IEEE Trans. Electron Devices, vol. 67, no. 10, pp. 4067–4072, Oct. 2020. DOI: 10.1109/TED.2020.3014563

8. N. Sekine, K. Toprasertpong, S. Takagi, and M. Takenaka, “Numerical analyses of optical loss and modulation bandwidth of an InP organic hybrid optical modulator,” Optics Express, vol. 28, no. 20, pp. 29730–29739, Sep. 2020. DOI: 10.1364/OE.402470

9. K. Kato, T. Tanamoto, T. Mori, Y. Morita, T. Matsukawa, M. Takenaka, and S. Takagi, “Impact of switching voltage on complementary steep-slope tunnel field effect transistor circuits,” IEEE Trans. Electron Devices, vol. 67, no. 9, pp. 3876–3882, September 2020. DOI: 10.1109/TED.2020.3010177

10. K. Sumita, J. Takeyasu, K. Toprasertpong, M. Takenaka, and S. Takagi, “Influence of layer transfer and thermal annealing on the properties of InAs-On-Insulator films,” J. Appl. Phys., vol. 128, 015705, July 2020. DOI: 10.1063/5.0007978

11. R. Takaguchi, M. Takenaka, and S. Takagi, “Diffusion properties of n-type dopants diffused from spin on glass into Ge,” J. Appl. Phys., vol. 128, 015707, July 2020. DOI: 10.1063/5.0002070

12. C.-M. Lim, Z. Zhao, K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takagi, “Operation of (111) Ge-on-insulator n-channel MOSFET fabricated by smart-cut technology,” IEEE Electron Dev., vol. 41, no. 7, pp. 985 – 988, 2020. DOI: 10.1109/LED.2020.2999777

13. K. Kato, T. Mori, Y. Morita, T. Matsukawa, M. Takenaka, and S. Takagi, “Source engineering for bilayer tunnel field effect transistor with hetero tunnel junction: Thickness and impurity concentration,” Appl. Phys. Express, Vol. 116, 242903, 2020. DOI: ??

14. K. Toprasertpong, K. Tahara, M. Takenaka, and S. Takagi, “Evaluation of polarization characteristics in metal/ferroelectric/semiconductor capacitors and ferroelectric field-effect transistors,” Appl. Phys. Lett., vol. ?, ??, 2020. DOI: 10.1063/5.0008060

15. Z. Zhao, C.-P. Ho, Q. Li, Z. Lin, K. Toprasertpong, S. Takagi and M. Takenaka, “Efficient mid-infrared germanium variable optical attenuator fabricated by spin-on-glass doping,” IEEE/OSA Journal of Lightwave Technology, vol. 38, no.17, pp. 4808–4816, 2020. 10.1109/JLT.2020.2995427

16. T.-E. Lee, M. Ke, K. Kato, M. Takenaka, and S. Takagi, “Metal-oxide-semiconductor interface properties of TiN/Y2O3/Si0.62Ge0.38 gate stacks with high temperature post metallization annealing,” J. Appl. Phys., vol. 127, 185705, 2020. DOI: 10.1063/1.5144198

17. M. Takenaka, Q. Li, S. Ohno, F. Boeuf, K. Toprasertpong, and S. Takagi, “III-V/Si hybrid optical modulators based on MOS capacitor,” Proc. SPIE, Integrated Photonics Platforms: Fundamental Research, Manufacturing and Applications, 1136402, 2020 (invited). DOI: 10.1117/12.2558305

18. K. Kato, H. Matsui, H. Tabata, T. Mori, Y. Morita, T. Matsukawa, M. Takenaka, and S. Takagi, “Improvement in electrical characteristics of ZnSnO/Si bilayer TFET by W/Al2O3 gate stack,” IEEE Journal of the Electron Devices Society, vol. 8, no. 1, pp. 341–345, 2020. DOI: 10.1109/JEDS.2020.2982424

19. K. Kato, K.-W. Jo, H. Matsui, H. Tabata, T. Mori, Y. Morita, T. Matsukawa, M. Takenaka, and S. Takagi, “P-channel TFET Operation of Bilayer Structures with Type-II Hetero Tunneling Junction of Oxide- and Group-IV-Semiconductors,” IEEE Trans. Electron Devices, vol. 67, no. 4, pp. 1880–1886, March 2020. DOI: 10.1109/TED.2020.2975582

20. C.-P. Ho, Z. Zhao, Q. Li, S. Takagi, and M. Takenaka, “Tunable germanium-on-insulator band-stop optical filter using thermo-optic effect,” IEEE Photonics Journal, vol. 12, no. 2 , pp. 1–7, April 2020. DOI: 10.1109/JPHOT.2019.2904050

21. K. Sumita, K. Kato, J. Takeyasu, K. Toprasertpong, M. Takenaka and S. Takagi, “Accurate evaluation of specific contact resistivity between InAs/Ni-InAs alloy by using a multi-sidewall transmission line method,” Jpn. J. Appl. Phys., vol. 59, SGGA08, 2020. DOI: 10.35848/1347-4065/ab6cb3

22. S. Ohno, K. Toprasertpong, S. Takagi, and M. Takenaka, “Si microring resonator crossbar arrays for deep learning accelerator,” Jpn. J. Appl. Phys., vol. 59, SGGE04, 2020. DOI: 10.35848/1347-4065/ab6d82

23. Y. Miyatake, N. Sekine, K. Toprasertpon, S. Takagi, and M. Takenaka, “Computational design of efficient grating couplers using artificial intelligence,” Jpn. J. Appl. Phys., vol. 59, SGGE09, 2020. DOI: 10.7567/1347-4065/ab641c

International conference

1. T.-E Lee, K. Toprasertpong, M. Takenaka and S. Takagi, “Characterization of slow traps in SiGe MOS interfaces by TiN/Y2O3 gate stacks,” IEEE International Reliability Physcis Symposium (IRPS2021), 2A.2, virtual, 21-25 March 2021.

2. S. Takagi, K. Toprasertpong, K. Kato, K. Sumita, E. Nako, R. Nakane, K.-W. Jo, and M. Takenaka, “Advanced CMOS technologies for ultra-low power logic and AI applications,” Electron Devices Technology and Manufacturing Conference (EDTM2020), Chengdu, China, 9–12 March 2021 (invited).

3. T.­E. Lee, Z. Lin, K. Toprasertpong, M. Takenaka, and S. Takagi, “– Revision of conductance method for evaluating interface state density at MFIS interfaces,” 51th IEEE Semiconductor Interface Specialists Conference (SISC), 11.2, virtual, 16–18 December 2020.

4. K. Sumita, K. Toprasertpong, M. Takenaka, and S. Takag, “Subband engineering by combination of channel thickness scaling and (111) surface orientation in InAs-on-insulator nMOSFETs,” International Electron Devices Meeting (IEDM2020), 2.5, San Francisco, 13–18 December 2020.

5. S. Ohno, K. Toprasertpong, S. Takagi, and M. Takenaka, “Demonstration of classification task using optical neural network based on Si microring resonator crossbar array,” European Conference on Optical Communication (ECOC 2020), Tu1C-4, Brussels, Belgium, 6–10 December 2020.

6. S. Ohno, Q. Li, N. Sekine, H. Tang, S. Monfray, F. Boeuf, K. Toprasertpong, S. Takagi, and M. Takenaka, “Si microring resonator switch based on III-V/Si hybrid MOS optical phase shifter using ultrathin InP membrane,” European Conference on Optical Communication (ECOC 2020), Tu1B-5, Brussels, Belgium, 6–10 December 2020.

7. Y. Miyatake, C.-P. Ho, P. Pitchappa, R. Singh, K. Makino, J. Tominaga, N. Miyata, T. Nakano, N. Sekine, K. Toprasertpong, S. Takagi, and M. Takenaka, “Mid-infrared non-volatile compact optical phase shifter based on Ge2Sb2Te5,” European Conference on Optical Communication (ECOC 2020), Tu2B-5, Brussels, Belgium, 6–10 December 2020.

8. M. Takenaka, “Si hybrid MOS optical modulators toward high-speed operation,” 10th International Symposium on Photonics and Electronics Convergence (ISPEC2020), E-4, Tokyo, 30 November–1 December 2020.

9. Y. Miyatake, C. P. Ho, P. Pitchappa, R. Singh, K. Makino, J. Tominaga, N. Miyata, T. Nakano, N. Sekine, K. Toprasertpong, S. Takagi, and M. Takenaka, “Non-volatile compact optical phase shifter based on Ge2Sb2Te5 operating at mid-infrared wavelength,” 10th International Symposium on Photonics and Electronics Convergence (ISPEC2020), S-5, Tokyo, 30 November–1 December 2020.

10. S. Ohno, K. Toprasertpong, S. Takagi, and M. Takenaka, “Demonstration of 4×4 microring resonator crossbar array for optical neural network,” 10th International Symposium on Photonics and Electronics Convergence (ISPEC2020), S-8, Tokyo, 30 November–1 December 2020.

11. Z. Zhao, C.-P. Ho, Q. Li, K. Toprasertpong, S. Takagi, and M. Takenaka, “Experimental evaluation of the free-carrier plasma dispersion effect in germanium,” 10th International Symposium on Photonics and Electronics Convergence (ISPEC2020), S-11, Tokyo, 30 November–1 December 2020.

12. Z. Zhao, C.-P. Ho, Q. Li, K. Toprasertpong, S. Takagi, and M. Takenaka, “Two-micrometer monolithic germanium waveguide photodetector integrated with lateral PIN junction,” 10th International Symposium on Photonics and Electronics Convergence (ISPEC2020), S-12, Tokyo, 30 November–1 December 2020.

13. R. Nur, T. Tsuchiya, M. Takenaka, K. Terabe, “Bandgap tuning of monolayer and bilayer MoS2 for broadband UV-VIS-NIR photodetection using an electric double layer device structure,” MRS Autumn Meeting, Symposium F.EL03.02.10, virtual, 27 November–4 December.

14. K. Toprasertpong, E. Nako, R. Nakane, Z. Wang, Y. Miyatake, M. Takenaka, and S. Takagi, “CMOS-compatible physical reservoir computing using ferroelectric field-effect transistors,” International Symposium on Nonlinear Theory and Its Applications (NOLTA2020), virtual, 16–19 Nov. 2020 (invited).

15. X. Luo, K. Toprasertpong, M. Takenaka, and S. Takagi, “Antiferroelectricity and cycling behavior of ALD ZrO2 ultra-thin films,” International Conference on Solid State Devices and Materials (SSDM), B-2-04, virtual, 27–30 Sept. 2020.

16. R. Nur, K. Toprasertpong, S. Takagi, and M. Takenaka, “Broadband UV-VIS-NIR photodetection with high responsivity MoS2 phototransistors based on light reflection,” International Conference on Solid State Devices and Materials (SSDM), H-10-06, virtual, 27–30 Sept. 2020.

17. K. Toprasertpong, K. Tahara, T. Fukui, Z. Lin, K. Watanabe, M. Takenaka, and S. Takagi, “Critical impact of ferroelectric-phase formation annealing on MFIS interface of HfO2-based Si FeFETs,” International Conference on Solid State Devices and Materials (SSDM), A-1-02, virtual, 27–30 Sept. 2020.

18. E. Nako, K. Tahara, R. Nakane, Z. Wang, M. Takenaka, and S. Takagi, “Demonstration of Reservoir Computing Using a Ferroelectric Capacitor,” International Conference on Solid State Devices and Materials (SSDM), B-9-03, virtual, 27–30 Sept. 2020.

19. K. Toprasertpon, Z.-Y. Lin, T.-E. Lee, M. Takenaka, and S. Takagi, “Asymmetric polarization response of electrons and holes in Si FeFETs: Demonstration of absolute polarization hysteresis loop and inversion hole density over 2×1013 cm-2,” VLSI Symposium, Hawaii, USA, 14–19 June 2020.

20. E. Nako, K. Toprasertpon, R. Nakane, Z. Wang, Y. Miyatake, M. Takenaka, and S. Takagi, “Proposal and experimental demonstration of reservoir computing using Hf0.5Zr0.5O2/Si FeFETs for neuromorphic applications,” VLSI Symposium, Hawaii, USA, 14–19 June 2020.

21. N. Sekine, K. Toprasertpong, S. Takagi, and M. Takenaka, “Active-passive integration on III-V-OI platform using quantum well intermixing,” Conference on Lasers and Electro-Optics (CLEO2020), STu3O.5, 11–15 May 2020.

22. M. Takenaka, Q. Li, S. Ohno, F. Boeuf, K. Toprasertpong, and S. Takagi, “III-V/Si hybrid optical modulators based on MOS capacitor,” SPIE Photonics Europe Digital Forum, 11364-1, 6–10 April 2020 (invited).