Silicon-based near infrared photoelectric detector structure and manufacturing method thereof

Abstract

The invention discloses a silicon-based near infrared photoelectric detector structure which comprises an n type silicon substrate, a phosphorus back field, a sulfur element doping layer, a p type boron doping layer, a see-through surface masking layer, an antireflection film layer, a front contact electrode and a back contact electrode, wherein two layers of step-shaped circular grooves are downwardly arranged above the n type silicon substrate; the phosphorus back field is arranged below the n type silicon substrate; the sulfur element doping layer is arranged in the lower circular groove above the n type silicon substrate; the p type boron doping layer is arranged in the upper circular groove above the n type silicon substrate; the see-through surface masking layer is arranged around the upper circular groove above the n type silicon substrate and covers the periphery of the p type boron doping layer; a circular hole is formed in the middle of the see-through surface masking layer; a ring-shaped groove is arranged at the periphery of the circular hole and the outer diameter of the ring-shaped groove is smaller than the diameter of the upper circular groove above the n type silicon substrate; the antireflection film layer is arranged in the circular hole in the middle of the see-through surface masking layer; the front contact electrode is arranged in the ring-shaped groove on the see-through surface masking layer; and the back contact electrode is arranged below the phosphorus back field. According to the silicon-based near infrared photoelectric detector structure, the difficulty that the traditional silicon photoelectric detectors have weak response to the near infrared lights with wavelengths greater than 1100nm can be solved, and particularly, the high-sensitivity near infrared photoelectric detection for the silicon-based photoelectric detectors can be realized.

Description

technical field [0001] The invention relates to a silicon photodetector structure and a manufacturing method thereof, in particular to a silicon-based near-infrared photodetector structure and a manufacturing method thereof. Background technique [0002] Based on the well-established silicon process, crystalline silicon is widely used to fabricate microelectronic and optoelectronic devices. However, the band gap of silicon is 1.12eV, which limits the application of silicon in the near-infrared band. The peak response wavelength of the traditional silicon photodetector is around 900nm, and its sensitivity to infrared light other than the wavelength of 1100nm is very low, so it cannot be used for photoelectric detection of the communication wavelength of 1330nm and 1550nm. Germanium and III-V materials are usually used to prepare photodetectors in the near-infrared communication band, but their high cost and poor silicon process compatibility limit their application range. ...

AI Technical Summary

Problems solved by technology

[0005] The main purpose of the present invention is to propose a silicon-based near-infrared photodetector structure and its manufacturing method, to solve the problem of weak response of traditional silicon-based photodetectors to near-infrared light with a wavelength greater than 1100nm, and to realize the high performance of silicon-based photodetectors. Sensitivity Near Infrared Photodetection

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