Open AccessImproved photoelectrical properties of n-ZnO/p-Si heterojunction by inserting an optimized thin Al_2O_3 buffer layer
Author(s) -
HongLiang Lu,
Yanfeng Gu,
Yuan Zhang,
Xinyan Li,
Pengfei Wang,
Qi Sun,
ShiJin Ding,
David Wei Zhang
Publication year - 2014
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.22.022184
Subject(s) - materials science , heterojunction , buffer (optical fiber) , layer (electronics) , optoelectronics , photodetector , dark current , crystal (programming language) , atomic layer deposition , diffraction , optics , nanotechnology , telecommunications , physics , computer science , programming language
The n-ZnO/p-Si heterojunction with an ultrathin Al₂O₃ buffer layer was prepared by atomic layer deposition. X-ray diffraction revealed that the crystalline quality of (100)-oriented ZnO films was improved with an Al₂O₃ buffer layer. The n-ZnO/p-Si heterojunction with 5 nm inserted Al₂O₃ layer shows the best electrical characteristics, with a dark current of 0.5 μA at a reverse bias of -2 V and increasing the photo-to-dark current ratio effectively by 8 times. These results demonstrated that Al₂O₃ buffer layer with optimized thickness exhibits significant advantages in enhancing the crystal quality of ZnO film and improving the photoelectrical properties of n-ZnO/p-Si photodetectors.