Open Access128-pixel arrays of 4H-SiC UV APD with dual-frequency PECVD SiNx passivation
Author(s) -
Xingye Zhou,
Xin Tan,
Yuanjie Li,
Jianbao Li,
Shixiong Liang,
Zi Hui Zhang,
Zhihong Feng,
Shujun Cai
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.402323
Subject(s) - passivation , plasma enhanced chemical vapor deposition , materials science , breakdown voltage , optoelectronics , dielectric , optics , avalanche photodiode , dark current , ultraviolet , chemical vapor deposition , voltage , biasing , photodetector , layer (electronics) , electrical engineering , detector , nanotechnology , physics , engineering
In this paper, high-performance 1×128 linear arrays of 4H-SiC ultraviolet (UV) avalanche photodiode (APD) with dual-frequency plasma enhanced chemical vapor deposition (PECVD) passivation are demonstrated for the first time. The results show that SiNx dielectric deposited by dual-frequency PECVD can effectively reduce the leakage current at high bias voltages. Due to the improved 4H-SiC epi-layer material and SiNx passivation, the fabricated 22 mm-long 1×128 4H-SiC APD linear arrays exhibit an excellent performance with a high pixel yield of 100% and a small breakdown voltage variation of 0.2 V, which is the best result ever reported. At room temperature, the pixels have a gain of over 10 5 and a maximum quantum efficiency of 53.5% @ 285 nm. Besides the high uniformity of breakdown voltage for 128 pixels, the dark currents at 95% of breakdown voltage are all below 1 nA.