A kind of preparation method of msm structure 4h-sic ultraviolet photodetector

Abstract

The invention discloses a method for preparing a 4H-SiC ultraviolet photoelectric detector of an MSM structure and relates to the preparation of ultraviolet photoelectric detectors. The method comprises the following steps: performing epitaxial growth of a semi-insulation layer on an n-shaped 4H-SiC substrate, cutting a material sample into a rectangular strip-shaped sample, cleaning the surface by adopting a standard RCA program, further adopting an electrothermal decomposition growth method, controlling the environmental conditions, temperature and growth time, electrifying two ends of the rectangular strip-shaped sample by using a DC direct current power supply, directly performing thermal growth of a multi-layer graphene film on the Si surface of the 4H-SiC epitaxial layer, optimizingthe growth technology conditions, and preparing an interdigital electrode for the MSM structure on the device surface by combining ICP etching by virtue of photolitho-pattern; combining sputtering deposition and a metal bonding pad, and covering and growing a dense SiO2 layer to serve as a passivation layer on the sample surface by virtue of plasma-enhanced chemical vapour deposition; and removingthe SiO2 in the circular bonding pad area by using lithography and etching, thereby obtaining the product.

Description

technical field [0001] The invention relates to the preparation of an ultraviolet photodetector, in particular to a method for preparing a MSM structure 4H-SiC ultraviolet photodetector with a graphene transparent electrode. Background technique [0002] The MSM structure 4H-SiC ultraviolet photodetector has important applications in the field of national defense and civil photodetection. The ultraviolet detector with this structure has the characteristics of simple preparation process, fast response speed and high quantum efficiency, and is suitable for the application of array detection devices. . Compared with traditional metal electrode materials, graphene is a new type of two-dimensional conductive material composed of a single layer of sp2 hybridized carbon atoms, which has good ultraviolet light transmittance and excellent optical, electrical and mechanical properties. Transparent electrodes can form good contact with semiconductor materials and have a wide range of ...

AI Technical Summary

Problems solved by technology

However, when various graphene preparation processes are considered to be applied to the actual work of the device, there is still room for improvement in terms of transfer area, surface quality, and contact effect with semiconductor materials. Therefore, it is necessary to explore the growth of graphene materials under different conditions. Characteristics and control measures, targeted use of preparation methods that can be applied to ultraviolet photodetectors, combined with optimization of the preparation process of 4H-SiC ultraviolet photodetectors with MSM structure, further improve the effective light transmittance and related electrical properties of the device, and realize Further improvement of weak ultraviolet signal detection capability

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