Shen, Y.; Li, Y.; Chen, W.; Jiang, S.; Li, C.; Cheng, Q. High-Performance Graphene Nanowalls/Si Self-Powered Photodetectors with HfO2 as an Interfacial Layer. Nanomaterials2023, 13, 1681.
Shen, Y.; Li, Y.; Chen, W.; Jiang, S.; Li, C.; Cheng, Q. High-Performance Graphene Nanowalls/Si Self-Powered Photodetectors with HfO2 as an Interfacial Layer. Nanomaterials 2023, 13, 1681.
Shen, Y.; Li, Y.; Chen, W.; Jiang, S.; Li, C.; Cheng, Q. High-Performance Graphene Nanowalls/Si Self-Powered Photodetectors with HfO2 as an Interfacial Layer. Nanomaterials2023, 13, 1681.
Shen, Y.; Li, Y.; Chen, W.; Jiang, S.; Li, C.; Cheng, Q. High-Performance Graphene Nanowalls/Si Self-Powered Photodetectors with HfO2 as an Interfacial Layer. Nanomaterials 2023, 13, 1681.
Abstract
Graphene/silicon (Si) heterojunction photodetectors are widely studied in detecting of optical signals from near-infrared to visible light. However, performance of the graphene/Si photodetectors is limited by defects created in the growth process and surface recombination at the interface. Herein, a remote plasma-enhanced chemical vapor deposition is introduced to directly grow graphene nanowalls (GNWs) at a low power, which can effectively improve the growth rate and reduce defects. Moreover, hafnium oxide (HfO2) grown by atomic layer deposition has been employed as an interfacial layer for the GNWs/Si heterojunction photodetector. It is shown that the high-k dielectric layer of HfO2 acts as an electron blocking and hole transport layer, which minimizes the recombination and reduces dark current. By optimizing the thickness of HfO2, an extremely low dark current of 3.85×10^(-10) A with a responsivity of 0.19 AW^(-1), as well as a specific detectivity of 1.38×10^12 Jones at zero bias can be obtained for the fabricated GNWs/HfO2/Si photodetector. This work demonstrates a universal strategy to fabricate high-performance graphene/Si photodetectors.
Keywords
hafnium oxide; graphene nanowalls; plasma-enhanced chemical vapor deposition; photodetectors
Subject
Chemistry and Materials Science, Nanotechnology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
