中国物理B ›› 2019, Vol. 28 ›› Issue (1): 18505-018505.doi: 10.1088/1674-1056/28/1/018505

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

Optimization of ambipolar current and analog/RF performance for T-shaped tunnel field-effect transistor with gate dielectric spacer

Ru Han(韩茹), Hai-Chao Zhang(张海潮), Dang-Hui Wang(王党辉), Cui Li(李翠)   

  1. School of Computer Science and Engineering, Northwestern Polytechnical University, Xi'an 710072, China
  • 收稿日期:2018-08-13 修回日期:2018-09-28 出版日期:2019-01-05 发布日期:2019-01-05
  • 通讯作者: Ru Han E-mail:hanru@nwpu.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61306116 and 61472322).

Optimization of ambipolar current and analog/RF performance for T-shaped tunnel field-effect transistor with gate dielectric spacer

Ru Han(韩茹), Hai-Chao Zhang(张海潮), Dang-Hui Wang(王党辉), Cui Li(李翠)   

  1. School of Computer Science and Engineering, Northwestern Polytechnical University, Xi'an 710072, China
  • Received:2018-08-13 Revised:2018-09-28 Online:2019-01-05 Published:2019-01-05
  • Contact: Ru Han E-mail:hanru@nwpu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61306116 and 61472322).

摘要:

A new T-shaped tunnel field-effect transistor (TTFET) with gate dielectric spacer (GDS) structure is proposed in this paper. To further studied the effects of GDS structure on the TTFET, detailed device characteristics such as current-voltage relationships, energy band diagrams, band-to-band tunneling (BTBT) rate and the magnitude of the electric field are investigated by using TCAD simulation. It is found that compared with conventional TTFET and TTFET with gate-drain overlap (GDO) structure, GDS-TTFET not only has the minimum ambipolar current but also can suppress the ambipolar current under a more extensive bias range. Furthermore, the analog/RF performances of GDS-TTFET are also investigated in terms of transconductance, gate-source capacitance, gate-drain capacitance, cutoff frequency, and gain bandwidth production. By inserting a low-κ spacer layer between the gate electrode and the gate dielectric, the GDS structure can effectively reduce parasitic capacitances between the gate and the source/drain, which leads to better performance in term of cutoff frequency and gain bandwidth production. Finally, the thickness of the gate dielectric spacer is optimized for better ambipolar current suppression and improved analog/RF performance.

关键词: tunneling field effect transistor, T-shaped tunnel field-effect transistor, gate dielectric spacer, ambipolar current, analog/RF performance

Abstract:

A new T-shaped tunnel field-effect transistor (TTFET) with gate dielectric spacer (GDS) structure is proposed in this paper. To further studied the effects of GDS structure on the TTFET, detailed device characteristics such as current-voltage relationships, energy band diagrams, band-to-band tunneling (BTBT) rate and the magnitude of the electric field are investigated by using TCAD simulation. It is found that compared with conventional TTFET and TTFET with gate-drain overlap (GDO) structure, GDS-TTFET not only has the minimum ambipolar current but also can suppress the ambipolar current under a more extensive bias range. Furthermore, the analog/RF performances of GDS-TTFET are also investigated in terms of transconductance, gate-source capacitance, gate-drain capacitance, cutoff frequency, and gain bandwidth production. By inserting a low-κ spacer layer between the gate electrode and the gate dielectric, the GDS structure can effectively reduce parasitic capacitances between the gate and the source/drain, which leads to better performance in term of cutoff frequency and gain bandwidth production. Finally, the thickness of the gate dielectric spacer is optimized for better ambipolar current suppression and improved analog/RF performance.

Key words: tunneling field effect transistor, T-shaped tunnel field-effect transistor, gate dielectric spacer, ambipolar current, analog/RF performance

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))