Characterization and Mobility Analysis of Normally off Hydrogen‐Terminated Diamond Metal–Oxide–Semiconductor Field‐Effect Transistors

作者：Jinfeng Zhang, Jin-Feng Zhang, Wanjiao Chen, Zeyang Ren, Kai Su, Pengzhi Yang, Zhuangzhuang Hu, Jin-Cheng Zhang, Jin-Cheng Zhang, Yue Hao · 发表于：physica status solidi (a) · 年份：2019 · DOI：10.1002/pssa.201900462 · 被引用次数：23 · 研究领域：Diamond and Carbon-based Materials Research、Semiconductor materials and devices、Advancements in Semiconductor Devices and Circuit Design

Hydrogen‐terminated diamond (H‐diamond) metal–oxide–semiconductor field‐effect transistors (MOSFETs) are fabricated, and a partial C–O channel is formed by UV‐ozone treatment of the H‐diamond surface to help realize normally off devices. The first parameterization of the vertical‐field ( F eff )‐dependent effective hole mobility ( μ eff ) in a normally off diamond FET is conducted using the fabricated MOSFETs with a gate length of 40 μm fat field‐effect transistors (FATFET). The FATFET with a threshold voltage of −0.69 V shows a low on‐resistance of 475.1 Ω mm and a record high drain current of −3.8 mA mm −1 for normally off H‐diamond MOSFETs with gate lengths over 20 μm. The extracted μ eff ranges from 127 cm 2 (V s) −1 (at V GS = −4.5 V) to 276 cm 2 (V s) −1 (at V GS = −1.5 V). Both μ eff versus F eff and μ eff versus V GS relations can be well fitted by the semiempirical formulas used for silicon counterparts. The resulting low‐field mobility without vertical‐field degradation for the two relations is 376 cm 2 (V s) −1 and 418 cm 2 (V s) −1 , respectively. The origin of this difference is also given.