中国物理B ›› 2018, Vol. 27 ›› Issue (7): 78502-078502.doi: 10.1088/1674-1056/27/7/078502

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Ge/Si heterojunction L-shape tunnel field-effect transistors with hetero-gate-dielectric

Cong Li(李聪), Zhi-Rui Yan(闫志蕊), Yi-Qi Zhuang(庄奕琪), Xiao-Long Zhao(赵小龙), Jia-Min Guo(郭嘉敏)   

  1. Wide Bandgap Semiconductor Technology Disciplines State Key Laboratory, School of Microelectronics, Xidian University, Xi'an 710071, China
  • 收稿日期:2018-02-02 修回日期:2018-04-18 出版日期:2018-07-05 发布日期:2018-07-05
  • 通讯作者: Cong Li E-mail:licong@xidian.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61574109 and 61204092).

Ge/Si heterojunction L-shape tunnel field-effect transistors with hetero-gate-dielectric

Cong Li(李聪), Zhi-Rui Yan(闫志蕊), Yi-Qi Zhuang(庄奕琪), Xiao-Long Zhao(赵小龙), Jia-Min Guo(郭嘉敏)   

  1. Wide Bandgap Semiconductor Technology Disciplines State Key Laboratory, School of Microelectronics, Xidian University, Xi'an 710071, China
  • Received:2018-02-02 Revised:2018-04-18 Online:2018-07-05 Published:2018-07-05
  • Contact: Cong Li E-mail:licong@xidian.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61574109 and 61204092).

摘要: A Ge/Si heterojunction L-shaped tunnel field-effect transistor combined with hetero-gate-dielectric (GHL-TFET) is proposed and investigated by TCAD simulation. Current-voltage characteristics, energy-band diagrams, and the distribution of the band-to-band tunneling (BTBT) generation rate of GHL-TFET are analyzed. In addition, the effect of the vertical channel width on the ON-current is studied and the thickness of the gate dielectric is optimized for better suppression of ambipolar current. Moreover, analog/RF figure-of-merits of GHL-TFET are also investigated in terms of the cut-off frequency and gain bandwidth production. Simulation results indicate that the ON-current of GHL-TFET is increased by about three orders of magnitude compared with that of the conventional L-shaped TFET. Besides, the introduction of the hetero-gate-dielectric not only suppresses the ambipolar current effectively but also improves the analog/RF performance drastically. It is demonstrated that the maximum cut-off frequency of GHL-TFET is about 160 GHz, which is 20 times higher than that of the conventional L-shaped TFET.

关键词: tunnel field-effect transistors, Ge/Si heterojunction, hetero-gate-dielectric, ambipolar effect

Abstract: A Ge/Si heterojunction L-shaped tunnel field-effect transistor combined with hetero-gate-dielectric (GHL-TFET) is proposed and investigated by TCAD simulation. Current-voltage characteristics, energy-band diagrams, and the distribution of the band-to-band tunneling (BTBT) generation rate of GHL-TFET are analyzed. In addition, the effect of the vertical channel width on the ON-current is studied and the thickness of the gate dielectric is optimized for better suppression of ambipolar current. Moreover, analog/RF figure-of-merits of GHL-TFET are also investigated in terms of the cut-off frequency and gain bandwidth production. Simulation results indicate that the ON-current of GHL-TFET is increased by about three orders of magnitude compared with that of the conventional L-shaped TFET. Besides, the introduction of the hetero-gate-dielectric not only suppresses the ambipolar current effectively but also improves the analog/RF performance drastically. It is demonstrated that the maximum cut-off frequency of GHL-TFET is about 160 GHz, which is 20 times higher than that of the conventional L-shaped TFET.

Key words: tunnel field-effect transistors, Ge/Si heterojunction, hetero-gate-dielectric, ambipolar effect

中图分类号:  (Semiconductor-device characterization, design, and modeling)

  • 85.30.De
85.30.Tv (Field effect devices) 85.30.Mn (Junction breakdown and tunneling devices (including resonance tunneling devices))