CN-122028522-A - Photoelectric detector, manufacturing method thereof and spectrometer

CN122028522ACN 122028522 ACN122028522 ACN 122028522ACN-122028522-A

Abstract

The application relates to a photoelectric detector, a manufacturing method thereof and a spectrometer, wherein the photoelectric detector comprises a P-type semiconductor substrate, a wide forbidden band oxide layer, a Schottky contact layer and a Schottky contact layer, wherein the P-type semiconductor substrate is used for generating electron-hole pairs under the effect of light to be detected, the wide forbidden band oxide layer is covered on the surface of the P-type semiconductor substrate, the thickness of the wide forbidden band oxide layer is 1-20nm, the top energy level of a valence band of the wide forbidden band oxide layer is at least lower than the top energy level of the valence band of a P-type semiconductor substrate material by 1.5eV and is used as a heterogeneous interface barrier layer, and the Schottky contact layer is covered on the surface of the wide forbidden band oxide layer. The photoelectric detector disclosed by the application adopts a vertical structure of the P-type semiconductor substrate/the wide bandgap oxide layer/the Schottky contact layer, and utilizes the unipolar barrier characteristic of the wide bandgap oxide layer and heterojunction energy band engineering, so that the device structure is simplified (photoetching is not needed), and meanwhile, the high-efficiency inhibition (in the order of 1 nA) and the effective collection of dark current are realized.

Inventors

GAO BINGTAO
CHEN ZHUOER
ZHANG YIYUN
LI SHILONG

Assignees

浙江大学杭州国际科创中心

Dates

Publication Date: 20260512
Application Date: 20260409

Claims (10)

1. A photoelectric detector, which comprises a light source, a light source and a light receiving element, characterized by comprising the following steps: the semiconductor device comprises a P-type semiconductor substrate, a light source and a light source, wherein the P-type semiconductor substrate is used for generating electron-hole pairs under the action of measured light; the wide energy gap oxide layer covers the surface of the P-type semiconductor substrate, the thickness of the wide energy gap oxide layer is 1nm-20nm, and the top energy level of the valence band of the wide energy gap oxide layer is at least lower than the top energy level of the valence band of the P-type semiconductor substrate material by 1.5eV and is used as a heterogeneous interface barrier layer; And the Schottky contact layer covers the surface of the wide forbidden band oxide layer.
2. The photodetector of claim 1 wherein the P-type semiconductor substrate is fabricated from a P-type semiconductor material or a P-type doped two-dimensional material.
3. The photodetector of claim 1 wherein said wide bandgap oxide layer is fabricated from gallium oxide, indium oxide or indium gallium oxide.
4. The photodetector of claim 1 wherein the schottky contact layer is fabricated from graphene, ITO, AZO, silver nanowires, or a metal film.
5. The photodetector of any one of claims 1 to 4, wherein in an operational state, a forward bias is applied to said schottky contact layer.
6. A method of fabricating a photodetector, comprising: providing a P-type semiconductor substrate and placing the P-type semiconductor substrate on a hot plate, wherein the temperature of the hot plate is 55-65 ℃; injecting liquid metal into the coating fixture tank; Maintaining the liquid metal in contact with the surface of the P-type semiconductor substrate at a micro-distance of 0.8-1.2 microns and moving the coating jig horizontally at a constant speed in a direction perpendicular to the coating jig at a speed of not more than 0.2 mm/s; In the moving process of the coating clamp, the liquid metal is flatly paved on the surface of the P-type semiconductor substrate under the combined action of shearing force and capillary force, a wide forbidden band oxide layer with the thickness of 1nm-20nm is formed in an atmosphere environment, and the top energy level of the valence band of the wide forbidden band oxide layer is at least 1.5eV lower than the top energy level of the valence band of the P-type semiconductor substrate material; Annealing at a temperature of 70-80 ℃ for 22-26 h; And forming a Schottky contact layer on the surface of the wide bandgap oxide layer in a temperature environment below 80 ℃.
7. The method of claim 6, wherein the liquid metal is liquid gallium, liquid indium or liquid indium gallium mixture.
8. A spectrometer, which comprises a light source, a light source and a light source, characterized by comprising the following steps: A photodetector according to any one of claims 1 to 5, for generating a training I-V curve under the action of laser light of different wavelengths and a measured I-V curve under the action of measured light; The normalization module is connected with the photoelectric detector and is used for acquiring the training I-V curve and the corresponding wavelength thereof, and performing normalization processing to generate a data set training network Isim; The deep neural network module is respectively connected with the photoelectric detector and the normalization module, is used for receiving the data set training network Isim and training the data set training network Isim in a model training stage, and is used for carrying out back propagation by a loss function of physical constraint while training to generate a spectrum reconstruction model, and is used for receiving the tested I-V curve in a spectrum reconstruction stage after the model training stage and generating a spectrum signal of tested light according to the spectrum reconstruction model.
9. The spectrometer of claim 8, wherein normalizing the training I-V curve and its corresponding wavelengths comprises normalizing the training I-V curve and its corresponding wavelengths based on a carrier transport physical model, wherein the carrier transport physical model is: Isim=R(λ,V)•Ssynth+N(μ,σ 2 ); Wherein R (lambda, V) is a spectral response matrix obtained by experimental measurement, ssynth is an analog spectrum, and N (mu, sigma 2 ) is Gaussian white noise.
10. The spectrometer of claim 8, wherein the loss function of the physical constraint is: ; Wherein, the The mean square error between the reconstructed result and the true result, In order to be a constraint of smoothness, Is that Is used for the weight coefficient of the (c), For the characteristic peak position constraint, Is that Is used for the weight coefficient of the (c), In order to be a constraint on the peak width, Is that Is used for the weight coefficient of the (c), In order for the relative intensity distribution constraint to be present, Is that Weight coefficient of (c) in the above-mentioned formula (c).

Description

Photoelectric detector, manufacturing method thereof and spectrometer Technical Field The invention relates to the technical field of semiconductor photoelectronic devices and intelligent sensing, in particular to a photoelectric detector, a manufacturing method thereof and a spectrometer. Background The photoelectric detector is used as a key front-end device of a photoelectric information system and plays a core role in the fields of optical communication, environment monitoring, biomedical imaging, machine vision and the like. With the rapid development of internet of things (IoT) and wearable devices, the market places stringent demands on miniaturization, integration, functionalization, and low-cost preparation of photodetectors. Currently, high performance photodetectors rely primarily on silicon or III-V compound semiconductors (e.g., gaAs, inP). However, as device dimensions shrink, the higher Dark Current (Dark Current) problem of conventional devices (silicon-based detectors tend to have higher thermally excited Dark Current at room temperature) limits the device's detection rate (DETECTIVITY) and signal-to-noise ratio. In order to suppress dark current, the prior art generally adopts a complex doping process, deep trench isolation or cryogenically cooling technology to thicken an insulating layer or make a complex structure. But this sacrifices the collection efficiency of the photogenerated carriers and increases the process complexity and the manufacturing cost significantly. Disclosure of Invention Accordingly, it is desirable to provide a photodetector and a method for manufacturing the same, which can suppress the generation of dark current with low manufacturing requirements and cost. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: A photodetector, comprising: the semiconductor device comprises a P-type semiconductor substrate, a light source and a light source, wherein the P-type semiconductor substrate is used for generating electron-hole pairs under the action of measured light; the wide energy gap oxide layer covers the surface of the P-type semiconductor substrate, the thickness of the wide energy gap oxide layer is 1nm-20nm, and the top energy level of the valence band of the wide energy gap oxide layer is at least lower than the top energy level of the valence band of the P-type semiconductor substrate material by 1.5eV and is used as a heterogeneous interface barrier layer; And the Schottky contact layer covers the surface of the wide forbidden band oxide layer. In one embodiment, the P-type semiconductor substrate is made of P-type semiconductor material or P-type doped two-dimensional material. In one embodiment, the wide bandgap oxide layer is made of gallium oxide, indium oxide or indium gallium oxide. In one embodiment, the schottky contact layer is made of graphene, ITO, AZO, silver nanowires or a metal film. In one embodiment, the schottky contact layer is forward biased in an operational state. Another embodiment discloses a method for manufacturing a photodetector, including: providing a P-type semiconductor substrate and placing the P-type semiconductor substrate on a hot plate, wherein the temperature of the hot plate is 55-65 ℃; injecting liquid metal into the coating fixture tank; Maintaining the liquid metal in contact with the surface of the P-type semiconductor substrate at a micro-distance of 0.8-1.2 microns and moving the coating jig horizontally at a constant speed in a direction perpendicular to the coating jig at a speed of not more than 0.2 mm/s; In the moving process of the coating clamp, the liquid metal is flatly paved on the surface of the P-type semiconductor substrate under the combined action of shearing force and capillary force, a wide forbidden band oxide layer with the thickness of 1nm-20nm is formed in an atmosphere environment, and the top energy level of the valence band of the wide forbidden band oxide layer is at least 1.5eV lower than the top energy level of the valence band of the P-type semiconductor substrate material; Annealing at a temperature of 70-80 ℃ for 22-26 h; And forming a Schottky contact layer on the surface of the wide bandgap oxide layer in a temperature environment below 80 ℃. In one embodiment, the liquid metal is liquid gallium, liquid indium, or a liquid indium gallium mixture. Another embodiment discloses a spectrometer comprising: the photoelectric detector is any one of the photoelectric detectors and is used for generating a training I-V curve under the action of lasers with different wavelengths and generating a tested I-V curve under the action of tested light; The normalization module is connected with the photoelectric detector and is used for acquiring the training I-V curve and the corresponding wavelength thereof, and performing normalization processing to generate a data set training network Isim; The deep neural network module is respectively connected with th