Near-infrared thermionic photodetector and preparation method thereof

Abstract

The invention discloses a near-infrared thermoelectron photodetector and a preparation method thereof. The near-infrared thermoelectron photodetector comprises: an n-type SOI sheet, the SOI sheet is used as a base, and the thickness of the silicon film on the top layer of the SOI sheet is 5 to 20 microns, a buried oxide layer is provided in the SOI sheet, and a thinning area is provided below the inside of the SOI sheet, and the thinning area separates the buried oxide layer, and the outer periphery of the thinning area A bottom electrode is provided; a nano-electrode is arranged on the top silicon film, and the nano-electrode and the top silicon film form a Schottky junction; a silicon nitride protective layer, the silicon nitride protective layer It is arranged on the top silicon film, and the silicon nitride protection layer wraps the nano-electrodes, and the silicon nitride protection layer is provided with contact holes for connecting external circuits. The invention can reduce the scattering loss in the thermal electron transport process, and improve the photoelectric response rate and response speed of the device.

Description

technical field [0001] The invention relates to the technical field of photodetectors, in particular to a near-infrared thermal electron photodetector and a preparation method thereof. Background technique [0002] Photodetectors are widely used in various fields of military and national economy. The working principle of the current mainstream semiconductor photodetectors is: when the incident photon energy is greater than the semiconductor band gap (hv>Eg), the photons excite electrons to the conduction band, and the The non-equilibrium electrons and holes generated in the space charge region are rapidly separated by the built-in electric field, resulting in photocurrent. The incident photon energy is greater than the semiconductor band gap, which is a necessary condition for photoelectric response. Therefore, this type of photodetector cannot detect or capture photons with energy less than the semiconductor band gap, which greatly limits its application in the fields of...

AI Technical Summary

Problems solved by technology

However, the huge scattering loss generated when the hot electrons are transported in the semiconductor causes most of the hot electrons to be recombined, resulting in the scattering loss during the hot electron transport, which greatly reduces the response speed of the device.

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