Design and Optimization of Germanium-Based Gate-Metal-Core Vertical Nanowire Tunnel FET

• Main Authors: Won Douk Jang, Young Jun Yoon, Min Su Cho, Jun Hyeok Jung, Sang Ho Lee, Jaewon Jang, Jin-Hyuk Bae, In Man Kang
• Format: Article
• Language: English
• Published: MDPI AG 2019-10-01
• Series: Micromachines
• Subjects: tunnel field-effect transistor (tfet); low power; vertical nanowire; core–shell; germanium; technology computer-aided design (tcad)
• Online Access: https://www.mdpi.com/2072-666X/10/11/749

In this paper, a germanium-based gate-metal-core vertical nanowire tunnel field effect transistor (VNWTFET) has been designed and optimized using the technology computer-aided design (TCAD) simulation. In the proposed structure, by locating the gate-metal as a core of the nanowire, a more extensive band-to-band tunneling (BTBT) area can be achieved compared with the conventional core&#8722;shell VNWTFETs. The channel thickness (<i>T</i>_ch), the gate-metal height (<i>H</i>_g), and the channel height (<i>H</i>_ch) were considered as the design parameters for the optimization of device performances. The designed gate-metal-core VNWTFET exhibits outstanding performance, with an on-state current (<i>I</i>_on) of 80.9 &#956;A/&#956;m, off-state current (<i>I</i>_off) of 1.09 &#215; 10^&#8722;12 A/&#956;m, threshold voltage (<i>V</i>_t) of 0.21 V, and subthreshold swing (SS) of 42.8 mV/dec. Therefore, the proposed device was demonstrated to be a promising logic device for low-power applications.