Barrier enhanced homotype heterojunction II type superlattice long/long wave two-color infrared detector

Abstract

The invention provides a barrier enhanced homotype heterojunction type II superlattice long / long wave double-color infrared detector. The infrared detector comprises a buffer layer, a P-type first ohmic contact layer, a P-type first long wave absorption layer, a P-type hole barrier layer, a P-type second long wave absorption layer and a P-type second ohmic contact layer which are sequentially epitaxially grown on a substrate, and the P-type first long-wave absorption layer and the P-type second long-wave absorption layer respectively form homotype doped heterojunctions with the P-type hole barrier layer. According to the structure disclosed by the invention, a bicolor detection function in a long wave band is realized through bias voltage modulation, and the structure is simple, through introduction of a homotype doped heterojunction and a single-barrier structure, compared with a traditional two-color detector of an NPPN structure, the two-color detector has the advantages that a space electric field in a long-wave absorption region is greatly reduced, composite dark current and tunneling dark current generated in the absorption region are effectively inhibited, and the signal-to-noise ratio and the detection rate of the device are improved.

Description

technical field [0001] The invention belongs to the technical field of semiconductor optoelectronic devices, in particular to a barrier-enhanced homoheterojunction type II superlattice long / long-wave dual-color infrared detector. Background technique [0002] With the different application environments of infrared detection systems, there are various factors affecting the accuracy of infrared detection systems, such as changing climate temperature, camouflage of detection targets, and release of infrared decoys, etc. Access to information has been weakened. Especially when the moving target itself changes, the wavelength corresponding to its infrared radiation peak will move, which will greatly reduce the detection accuracy of the infrared detection system and may even fail to detect the target. Compared with single-color detectors, dual-color detectors can measure remote temperature, and can work in a wider atmospheric environment, more accurately distinguishing between ta...

AI Technical Summary

Problems solved by technology

However, the space charge region in the PIN structure is prone to generate G-R dark current and tunneling dark current due to the existence of the built-in electric field. Especially for long-wave infrared detectors, the dark current generated in the space charge region is relatively small due to the narrow band gap. Since the medium and short wave detectors have been greatly improved, the performance of long wave infrared detectors is more severely restricted by dark current noise

Images