A germanium silicon avalanche photodetector

Abstract

The invention provides a germanium-silicon avalanche photodetector, comprising: an avalanche amplification region; a first ohmic contact layer and a charge collection region respectively in contact with the avalanche amplification region; a control gate structure connected to the charge collection region; Wherein, the control gate structure is used to control the barrier height of the charge collection region. That is to say, based on the control gate structure, the silicon germanium avalanche photodetector controls the barrier height of the charge collection region by adjusting the gate voltage, so that only the carrier accumulation potential energy in the dark current is higher than a certain potential barrier Only when it is allowed to pass through, the dark current of the germanium-silicon avalanche photodetector is reduced, and the photoelectric conversion efficiency is improved.

Description

technical field [0001] The present invention relates to the technical field of detectors, and more particularly, to a germanium-silicon avalanche photodetector. Background technique [0002] As a weak light detector, germanium-silicon avalanche photodiode (Avalanche Photo Diode, APD for short) has very important applications in many aspects such as optical communication, laser imaging and lidar. [0003] APDs in the visible light and near-infrared bands (300nm-1000nm) generally use Si materials, which are now very mature. APDs in the mid-infrared band (1.3μm-1.7μm) generally use III-V materials. The technology is very mature, but the cost is high and the uniformity is not good. It is very difficult to fabricate APD arrays in this band. In addition, silicon-based photonics has developed very rapidly in the past ten years. On the one hand, silicon-based photonics is fully compatible with silicon-based integrated circuits, and silicon-based optoelectronic chips will be very ch...

AI Technical Summary

Problems solved by technology

However, the research on Ge as a low-light detector-avalanche photodiode has just begun, and it has a series of problems such as large dark current and low photoelectric conversion efficiency.

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