High photoresponse near-infrared photodetector

Abstract

A near-infrared photoelectric detector with high light response is characterized by comprising a transparent inertia substrate, an antimony selenide thin film and an electrode. The antimony selenide thin film is subjected to selenization. The selenization includes: annealing the antimony selenide thin film in selenium atmosphere at the annealing temperature of 150-400 DEG C for 5-30 minutes, wherein the selenium steam partial pressure of the selenium atmosphere is 1-10000Pa; or depositing a layer of selenium on the surface of the antimony selenide thin film before annealing, wherein the thickness of the deposited selenium is 1-500 nanometers, the annealing temperature is 150-400 DEG C, and the annealing time is 10-60 minutes. The near-infrared photoelectric detector is rich in raw material, cheap, simple in process, economic, high in operability, and high in sensitivity.

Description

technical field [0001] The invention belongs to the technical field of semiconductor optoelectronic devices, and in particular relates to a near-infrared photodetector with high light response. Background technique [0002] Antimony selenide (Sb 2 Se 3 ) belongs to group V-VI banded compound semiconductors, has good photoelectric response and thermoelectric effect, and is a potential thin-film photovoltaic absorber material. It has a suitable band gap of 1-1.2eV and a large absorption coefficient ( Shortwave absorption coefficient>10 5 cm -1 ), the raw material is non-toxic and abundant, but its application has not been taken seriously. So far, there has been no report on the use of antimony selenide in the preparation of photodetectors. [0003] In recent years, with the development of optical communication technology, the preparation of near-infrared photodetectors with high response, high quantum efficiency, high specific detectivity and high response frequency b...

AI Technical Summary

Problems solved by technology

Detectors made of III-V semiconductor materials such as InGaAs / InP have high quantum efficiency and low dark current, but their high price, poor thermal conductivity and mechanical properties limit their application in optoelectronic integration technology

In the relevant literature reported before, we know that doping can significantly change the carrier concentration of semiconductor materials, especially for transparent conductive films, doping impurities can make it have a high carrier concentration, thus affecting its forbidden Band width, for example, the patent with authorized notification number CN 100541828C discloses a photodetector for 650nm optical fiber communication, which is heavily doped P + Surface layer / P-type layer / Low-doped N - Type epitaxial layer / heavily doped N + The substrate layer has a four-layer structure, and the resulting detector has good I-V characteristics, small dark current, and high photoresponsivity. However, the process of this method is relatively complicated, and the doping amount needs to be strictly and effectively controlled. The reaction conditions are harsh and the processing cost is high. The degree of industrialization is low; the application publication number is CN103280484A The patent discloses a p-type graphene film / n-type Ge Schottky junction near-infrared photodetector and its preparation method. The authorized announcement number is CN101576413 C's patent is a GaAs-based InAs / GaSb superlattice infrared photodetector in the 1 to 3 micron band. The infrared photodetector consists of a bottom-up GaAs substrate, a GaAs buffer layer, an AlSb nucleation layer, and a GaSb lower buffer layer, AlSb / GaSb superlattice layer, GaSb upper buffer layer, InAs / GaSb superlattice layer, GaSb capping layer and titanium gold alloy electrode

, but these methods will encounter many new problems in actual operation and increase the cost of detector production

[0004] The doping concentration of the antimony selenide film prepared by various processes in the prior art is low, only at 10 13 ~10 14 cm -3 around, which limits the improvement of the photoresponse of antimony selenide thin film photodetectors

The patent application publication number CN103343323 A discloses a method for preparing a copper indium gallium selenide thin film, including selenization and annealing of the copper indium gallium selenide pre-layer, that is, copper indium gallium, but the processing method is mainly for the preparation of Copper indium gallium selenide thin film, control the proportion of complex quaternary compounds of copper indium gallium selenide, thereby improving the photoelectric conversion efficiency of solar cells with copper indium gallium selenide thin film, and no relevant literature has been found to improve the photoelectricity of antimony selenide thin film through selenization response and then use it to fabricate antimony selenide thin film near-infrared photodetectors

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