Open AccessUltra-low threshold avalanche gain from solar-blind photodetector based on graded-band-gap-cubic-MgZnO
Author(s) -
Xiuhua Xie,
Zhenzhong Zhang,
Binghui Li,
Shuangpeng Wang,
Dezhen Shen
Publication year - 2015
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.23.032329
Subject(s) - responsivity , photodetector , materials science , optoelectronics , heterojunction , band gap , optics , electric field , physics , quantum mechanics
A larger ratio of conduction-band offset to valence-band offset is the unique character for Mg(x)Zn(1-x)O alloys. For this reason, it is feasible to build a quasi-electric forces, caused by the spatial gradient of the conduction edge, exerting on the electrons. In this paper, a novel graded band gap cubic-MgZnO-based solar-blind photodetector is successfully fabricated from Graded-Band-Gap-Cubic-MgZnO/i-MgO/p-Si heterojunction, via changing stoichiometry spatial gradient. Due to quasi-electric fields in non-uniform MgZnO, the multiple carriers are generated under ultra-low threshold bias voltage. The photodetector showed high performance, namely, high responsivity, quantum efficiency, high sensitivity and selectivity towards the solar-blind spectrum, and fast response times.