CN-116314380-B - Monolithically integrated resonant cavity enhanced waveguide photodetector

CN116314380BCN 116314380 BCN116314380 BCN 116314380BCN-116314380-B

Abstract

The invention relates to the technical field of photoelectricity and provides a monolithically integrated resonant cavity enhanced waveguide photodetector, which comprises a semi-insulating substrate, a waveguide photodetector epitaxial layer, an N metal electrode and a P metal electrode, wherein the waveguide photodetector epitaxial layer comprises a waveguide layer and a photodetector epitaxial layer, the semi-insulating substrate, the waveguide layer, the photodetector epitaxial layer and the P metal electrode are sequentially arranged along the Z-axis direction, the N metal electrode is connected with the waveguide layer, the waveguide photodetector epitaxial layer is provided with a first end and a second end which are opposite along the X-axis direction, the photodetector epitaxial layer is provided with a first groove, the waveguide photodetector epitaxial layer is provided with a second groove, the first groove is arranged close to the first end, the second groove is arranged close to the second end, and the first groove and the second groove are all arranged along the Y-axis direction.

Inventors

NIU HUIJUAN
FAN XINYE
BAI CHENGLIN
JIANG CHUANXING
ZHANG LUJIAN

Assignees

聊城大学

Dates

Publication Date: 20260512
Application Date: 20221118

Claims (9)

1. The monolithically integrated resonant cavity enhanced waveguide photodetector is characterized by comprising a semi-insulating substrate, a waveguide photodetector epitaxial layer, an N metal electrode and a P metal electrode; the waveguide light detector epitaxial layer comprises a waveguide layer and a light detector epitaxial layer, the semi-insulating substrate, the waveguide layer, the light detector epitaxial layer and the P metal electrode are sequentially arranged along the Z-axis direction, and the N metal electrode is connected with the waveguide layer; The waveguide light detector epitaxial layer is provided with a first end and a second end which are opposite to each other along the X-axis direction, the light detector epitaxial layer is provided with a first groove, the waveguide light detector epitaxial layer is provided with a second groove, the first groove is close to the first end, the second groove is close to the second end, and the first groove and the second groove are distributed along the Y-axis direction; The second grooves are arranged in a plurality, and the second grooves are arranged at intervals along the X-axis direction; the depth of the first groove is smaller than that of the second groove, medium is filled in the first groove and the second groove to form a distributed Bragg reflector with the semiconductor material alternately, and a resonant cavity is formed between the first groove and the second groove.
2. The monolithically integrated cavity enhanced waveguide light detector of claim 1, wherein, The first groove extends from the middle of the photo detector epitaxial layer towards the two ends of the photo detector epitaxial layer along the Y-axis direction; The second grooves extend from the middle of the waveguide photodetector epitaxial layer towards the two ends of the photodetector epitaxial layer along the Y-axis direction.
3. The monolithically integrated cavity enhanced waveguide light detector of claim 2, wherein, The extension distance of the first groove extending from the middle part of the light detector epitaxial layer towards the two ends along the Y-axis direction is equal to L1/2; the second groove extends from the middle part of the waveguide light detector epitaxial layer towards the two ends along the Y-axis direction, and the extending distance is equal to L1/2; Wherein L1 is the width of the photo detector epitaxial layer along the Y-axis direction.
4. The monolithically integrated cavity enhanced waveguide light detector of claim 2, wherein, The extension distance of the first groove extending from the middle part of the light detector epitaxial layer towards the two ends along the Y-axis direction is smaller than L1/2; the second groove extends from the middle part of the waveguide light detector epitaxial layer towards the two ends along the Y-axis direction, and the extending distance is smaller than L1/2; Wherein L1 is the width of the photo detector epitaxial layer along the Y-axis direction.
5. The monolithically integrated cavity enhanced waveguide light detector of claim 1, wherein, The first groove comprises a first groove body and a second groove body, wherein the first groove body and the second groove body are collinear, the second groove comprises a third groove body and a fourth groove body, and the third groove body and the fourth groove body are collinear; The first groove body and the second groove body extend from the edge of the optical detector epitaxial layer towards the middle of the optical detector epitaxial layer along the Y-axis direction, and the third groove body and the fourth groove body extend from the edge of the optical detector epitaxial layer towards the middle of the waveguide optical detector epitaxial layer along the Y-axis direction; The first groove body and the second groove body form a first interval along the Y-axis direction, and the third groove body and the fourth groove body form a second interval along the Y-axis direction.
6. The monolithically integrated cavity enhanced waveguide light detector of claim 1, wherein, The distance between two adjacent second grooves is Klambda/4 n1; where K is a positive odd number, λ is the wavelength of the incident light, and n1 is the refractive index of the waveguide layer.
7. The monolithically integrated cavity enhanced waveguide light detector of claim 1, wherein, The widths of the first groove and the second groove along the X-axis direction are equal, and are N lambda/4N 2; Wherein N is a positive odd number, λ is the wavelength of the incident light, and N2 is the refractive index of the medium in the first groove and the second groove.
8. The monolithically integrated cavity enhanced waveguide light detector of claim 1, wherein, The light detector epitaxial layer comprises a collecting layer, a cliff layer, a spacer layer, an absorbing layer, an electron blocking layer and a P contact layer; The collecting layer, the cliff layer, the spacer layer, the absorbing layer, the electron blocking layer and the P contact layer are sequentially arranged along the Z-axis direction, the collecting layer is connected with the waveguide layer, and the P contact layer is connected with the P metal electrode.
9. The monolithically integrated cavity enhanced waveguide light detector of claim 1, wherein, The cross-sectional shapes of the first groove and the second groove on a plane perpendicular to the Y-axis direction are square.

Description

Monolithically integrated resonant cavity enhanced waveguide photodetector Technical Field The invention relates to the technical field of photoelectricity, in particular to a monolithically integrated resonant cavity enhanced waveguide photodetector. Background The photodetector is used for converting optical signals into electric signals and has wide application in the aspects of high-speed high-power optical fiber communication systems, wireless optical fiber communication systems, terahertz wave sources and the like, wherein the measurement indexes of the performance of the photodetector comprise responsivity, response speed and the like, The waveguide photodetector is one of the photodetectors, and in order to enable incident light to be absorbed as much as possible, that is, in order to ensure responsiveness, the area of an active region of the waveguide photodetector is required to be large, but the active area is inversely proportional to the response speed, that is, the large active area causes a decrease in the response speed, so that it is difficult for the waveguide photodetector to satisfy both good responsiveness and a fast response speed. Disclosure of Invention The invention provides a monolithically integrated resonant cavity enhanced waveguide photodetector, which is used for solving or improving the problem that the existing waveguide photodetector is difficult to simultaneously meet good responsivity and faster response speed. The invention provides a monolithically integrated resonant cavity enhanced waveguide photodetector, which comprises a semi-insulating substrate, a waveguide photodetector epitaxial layer, an N metal electrode and a P metal electrode, wherein the waveguide photodetector epitaxial layer comprises a waveguide layer and a photodetector epitaxial layer, the semi-insulating substrate, the waveguide layer, the photodetector epitaxial layer and the P metal electrode are sequentially arranged along the Z-axis direction, the N metal electrode is connected with the waveguide layer, the waveguide photodetector epitaxial layer is provided with a first end and a second end which are opposite in the X-axis direction, the photodetector epitaxial layer is provided with a first groove, the waveguide photodetector epitaxial layer is provided with a second groove, the first groove is arranged close to the first end, the second groove is arranged close to the second end, and the first groove and the second groove are both arranged along the Y-axis direction. According to the monolithically integrated resonant cavity enhanced waveguide photodetector provided by the invention, the first groove extends from the middle part of the photodetector epitaxial layer towards the two ends of the photodetector epitaxial layer along the Y-axis direction, and the second groove extends from the middle part of the waveguide photodetector epitaxial layer towards the two ends of the photodetector epitaxial layer along the Y-axis direction. According to the monolithically integrated resonant cavity enhanced waveguide photodetector provided by the invention, the extension distance of the first groove extending from the middle part of the photodetector epitaxial layer towards the two ends along the Y-axis direction is equal to L1/2, the extension distance of the second groove extending from the middle part of the waveguide photodetector epitaxial layer towards the two ends along the Y-axis direction is equal to L1/2, and L1 is the width of the photodetector epitaxial layer along the Y-axis direction. According to the monolithically integrated resonant cavity enhanced waveguide photodetector provided by the invention, the extension distance of the first groove extending from the middle part of the photodetector epitaxial layer towards the two ends along the Y-axis direction is smaller than L1/2, the extension distance of the second groove extending from the middle part of the waveguide photodetector epitaxial layer towards the two ends along the Y-axis direction is smaller than L1/2, and L1 is the width of the photodetector epitaxial layer along the Y-axis direction. The monolithically integrated resonant cavity enhanced waveguide photodetector comprises a first groove body and a second groove body, wherein the first groove body and the second groove body are collinear, the second groove body comprises a third groove body and a fourth groove body, the third groove body and the fourth groove body are collinear, the first groove body and the second groove body extend from the edge of a photodetector epitaxial layer towards the middle of the photodetector epitaxial layer along the Y-axis direction, the third groove body and the fourth groove body extend from the edge of the photodetector epitaxial layer towards the middle of the waveguide photodetector epitaxial layer along the Y-axis direction, the first groove body and the second groove body form a first interval along the Y-axis direction, and the third gro