High-gain graphene photodetector based on double gate voltage regulation and preparation method thereof

Abstract

The invention discloses a high-gain graphene photodetector based on double gate voltage regulation and a preparation method thereof. Wherein, the detector includes a substrate with a top layer semiconductor, an intermediate layer insulating medium and a bottom layer semiconductor from top to bottom; it also includes a drain electrode, a source electrode, a top gate electrode and a bottom gate electrode, the drain electrode and the source electrode The electrodes are respectively arranged at both ends above the top semiconductor; it also includes a device channel between the drain electrode and the source electrode, and an ion insulating layer covering the device channel; the top gate electrode and the bottom gate electrode are respectively connected with the device channel. The drain electrode and the source electrode are connected, and are also connected with the ion insulating layer and the underlying semiconductor respectively. The detector uses the bottom gate to control the concentration and distribution of carriers in the semiconductor thin film, while the top gate controls the concentration and type of carriers in graphene through ion gel, extending the response band from visible light to near-infrared band. The speed is increased while the response time is also accelerated.

Description

technical field [0001] The invention relates to the technical field of photoelectric detection, in particular to a high-gain graphene photodetector based on double gate voltage regulation and a preparation method thereof. Background technique [0002] With the increasing development demands for miniaturization, integration, and high performance of optoelectronic devices, graphene is considered to be a promising material due to its excellent optoelectronic properties. [0003] The low optical absorption rate (2.3%) and short carrier lifetime (1 ps) of graphene lead to the extremely low quantum efficiency of graphene, which has always been a challenge for its application in optoelectronic devices. Photodetectors that utilize graphene itself as a light-absorbing material have low quantum efficiencies. [0004] The graphene composite structure photodetector based on the grating pressure mechanism provides a gain for the device, enabling it to obtain high photoresponsivity. How...

AI Technical Summary

Problems solved by technology

However, the increase in gain is based on the trap effect, that is, at the expense of device response time

[0005] Due to the uncontrollability of graphene doping and the instability of interface contact, the performance of composite structure photodetectors is usually difficult to achieve controllability, and its interface coupling effect is also difficult to achieve the best.

Images