Open AccessLow dark current and high gain-bandwidth product of avalanche photodiodes: optimization and realization
Author(s) -
Hui Wang,
Xun Yang,
Rui Wang,
Tingting He,
Kaibao Liu
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.393063
Subject(s) - avalanche photodiode , dark current , optoelectronics , photodiode , optics , materials science , bandwidth (computing) , photonics , photodetector , physics , telecommunications , detector , computer science
In this paper, a new method combining carrier transport in semiconductors with an RF equivalent circuit was put forward to simulate the frequency response of an avalanche photodiode (APD). The main trade-off between the gain-bandwidth product (GBP) and the dark current was analyzed to optimize the structure of an APD; and a separated absorption, grading, charge, multiplication, charge, transit (SAGCMCT) structure with 120 nm balanced InAlAs multiplication layer was proposed to reduce the dark current and improve the frequency response. The fabricated triple-mesa type back-illuminated InGaAs/InAlAs APD achieved the properties of low dark current of 6.7 nA at 0.9V b and high GBP over 210 GHz.