AlGan polarized ultraviolet photoelectric detector and manufacturing method thereof

Abstract

The invention discloses an AlGan material-based ultraviolet photoelectric detector structure and a manufacturing method thereof, which are mainly used for solving the problem of the dependence on a P-type doping material in the prior art. A detector comprises a substrate (1), a transition layer (2), a GaN buffer layer (3), an aluminum component gradual change AlGaN layer (4) and an active layer (5) from bottom to top, wherein the aluminum component gradual change AlGaN layer (4) is partitioned into an upper layer and a lower layer; the thickness of the lower layer is 20-30 nanometers, and thecontent of an aluminum component increases from 0 percent to 80-100 percent; the thickness of the upper layer is 10-20 nanometer, and the content of the aluminum component is 0-80 percent; the left upper side of the aluminum component gradual change AlGaN layer (4) is covered by the active layer (5); a bottom ohmic contact (7) is deposited on the right upper side of the aluminum component gradualchange AlGaN layer (4); a gap (8) is formed between the ohmic contact and the active region; the active region (5) consists of an AlGaN material with the aluminum component content of 0-80 percent; the thickness of the active region (5) is 50-100 nanometers; and a surface ohmic contact electrode (7) is deposited on the surface of the active region. The detector structure has the advantages of capability of automatically working in a photovoltaic mode, high high-frequency characteristic and small dark current, and can be applied to optical signal detection in ultraviolet wavebands between 226 nanometers and 363 nanometers.

Description

technical field [0001] The invention belongs to the technical field of microelectronics, and in particular relates to an AlGaN ultraviolet photodetector, which can be used for optical signal detection in the 226-363nm ultraviolet band. Background technique [0002] A semiconductor photodetector is a detector that changes the electrical properties of semiconductor materials by receiving light wave irradiation, thereby realizing the detection and resolution of targets. Changing the material and structural parameters of the semiconductor used can tune the range of response wavelengths. Those whose response wavelength is in the ultraviolet band are called semiconductor ultraviolet photodetectors. With the extensive use of microelectronic integrated circuit technology in aerospace, the original gas-phase and liquid-phase ultraviolet detectors are gradually replaced by this solid-state detector. The European Space Agency ESA's Solar Obiter program is ready to be realized in 2015...

AI Technical Summary

Problems solved by technology

Due to the restriction of the quality of the current AlGaN material film, there are a large number of defects on the surface of the AlGaN material when it forms a Schottky junction with the deposited metal on the surface, which makes the active region thinner, the tunneling mechanism is obvious, and the dark current is very large, which seriously restricts this technology. Improvement of detection performance of similar structures, see AlGaN Schottky Diodes for Detector Applications in the UV Wavelength Range.IEEE Trans.Electron Devices 56, 2833(2009)

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