CN210092101U

CN210092101U - MQW structure InGaN blue light detector

Info

Publication number: CN210092101U
Application number: CN201920907832.XU
Authority: CN
Inventors: 杨国锋; 周东; 渠凯军
Original assignee: Nanjing Purple Light Technology Co Ltd
Current assignee: Nanjing Purple Light Technology Co Ltd
Priority date: 2019-06-17
Filing date: 2019-06-17
Publication date: 2020-02-18
Anticipated expiration: 2029-06-17

Abstract

The utility model discloses a MQW structure InGaN blue light detector, including graphical sapphire substrate, unintended doping GaN buffer layer, N type heavily doped GaN ohmic contact layer, InGaN/GaN multiple quantum well MQW absorbed layer, P type doping GaN ohmic contact layer, P type ohmic contact electrode, medium passivation layer, N type ohmic contact electrode and P type contact Pad electrode. The utility model has the advantages of adopt the alternately MQW absorbed layer structural design who grows of InGaN and GaN, avoided the high In component InGaN material of traditional PIN structure blue light detector to easily appear and difficult problem of growing, and make simple process and present LED technology compatible.

Description

MQW structure InGaN blue light detector

Technical Field

The utility model relates to a semiconductor photoelectric device technical field, concretely relates to MQW structure InGaN blue light detector.

Background

The blue light communication is one of laser communication, and adopts blue light beams with the light wave wavelengths of 450 and 570 nm. The seawater has extremely low absorption loss of visible light in a blue light wave band, so that when blue-green light passes through the seawater, the seawater has strong penetrating power and excellent directivity, is one of important communication modes for transmitting information in deep sea, and is also applied to the fields of mine exploration, depth sounding and the like. The core of the blue light communication technology is to develop a high-sensitivity blue light detector. With the development of the third generation semiconductor photoelectric detection technology in recent years, the GaN-based material has the characteristics of continuously adjustable forbidden bandwidth (0.7-6.2 eV), radiation resistance and high temperature resistance, and has become an optimized material for manufacturing a high-sensitivity blue light detector. However, currently, InGaN materials are mainly obtained by heteroepitaxy, and generally, In is very easy to precipitate during the growth process of the heteroepitaxy InGaN materials, and often has high dislocation density (ii) ((iii))>5×10⁸cm^-2). Dislocations in the material are not only the leakage path of the device but can also lead to destructive breakdown of the avalanche device. In order to improve the growth difficulty of the InGaN-based blue light detector epitaxial material, a growth mode of an MQW structure is provided, the growth difficulty of the material is greatly reduced, the dark current of a device is reduced, and a foundation is laid for batch production.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a novel MQW structure InGaN blue light detector of optimizing structure and simple process.

The utility model discloses a following technical scheme realizes above-mentioned purpose:

an InGaN blue light detector with MQW structure comprises

Patterning the sapphire substrate;

extending an unintended doped GaN buffer layer on the front surface of the graphical sapphire substrate in an epitaxial mode;

an N-type heavily-doped GaN ohmic contact layer is epitaxially grown on the front surface of the unintended doped GaN buffer layer;

sequentially extending InGaN/GaN multi-quantum well MQW absorption layers on the front surface of the N-type heavily-doped GaN ohmic contact layer;

extending a P-type doped GaN ohmic contact layer on the front surface of the InGaN/GaN multi-quantum well MQW absorption layer in an epitaxial manner;

manufacturing a P-type ohmic contact electrode on the P-type GaN-doped ohmic contact layer;

a dielectric passivation layer deposited on the front surface of the P-type ohmic contact electrode, wherein a lead hole capable of exposing the P-type ohmic contact electrode is etched in the dielectric passivation layer;

and arranging an N-type ohmic contact electrode and a P-type contact Pad electrode manufactured at the position of the lead hole on the N-type heavily-doped GaN ohmic contact layer, wherein the P-type contact Pad electrode extends into the lead hole and is connected with the P-type ohmic contact electrode.

The further improvement is that the In component of the InGaN/GaN multi-quantum well MQW absorption layer is 0.05-0.3, the thickness of an InGaN single layer is 3nm-5nm, the thickness of a GaN single layer is 15nm-20nm, and the total thickness of the InGaN is set to be 100 nm.

The further improvement is that the thickness of the P-type doped GaN ohmic contact layer is 20nm-80 nm.

The P-type ohmic contact electrode is a semitransparent electrode, the semitransparent electrode is a Ni/Au, Pt/Au or graphene electrode, and the total thickness of the electrode is less than or equal to 5 nm.

The further improvement is that the medium passivation layer is SiO₂And (3) a layer.

In addition, the P-type ohmic contact electrode, the N-type ohmic contact electrode and the P-type contact Pad electrode are all manufactured by adopting an electron beam evaporation method.

The beneficial effects of the utility model reside in that: the utility model has the advantages of adopt the alternately MQW absorbed layer structural design who grows of InGaN and GaN, avoided the high In component InGaN material of traditional PIN structure blue light detector to easily appear and difficult problem of growing, and make simple process and present LED technology compatible.

Drawings

Fig. 1 is a schematic structural view of the present invention;

in the figure: 101. patterning the sapphire substrate; 102. unintentionally doping the GaN buffer layer; 103. an N-type heavily doped GaN ohmic contact layer; 104. an InGaN/GaN multi-quantum well MQW absorption layer; 105. a P-type GaN-doped ohmic contact layer; 106. a P-type ohmic contact electrode; 107. a dielectric passivation layer; 108. an N-type ohmic contact electrode; 109. the P-type contacts Pad electrodes.

Detailed Description

The present application will now be described in further detail with reference to the drawings, it should be noted that the following detailed description is given for illustrative purposes only and is not to be construed as limiting the scope of the present application, as those skilled in the art will be able to make numerous insubstantial modifications and adaptations to the present application based on the above disclosure.

As shown in fig. 1, an embodiment structure of an MQW-structure InGaN blue light detector is shown, including a patterned sapphire substrate 101, on which an unintentional doped GaN buffer layer 102 with a thickness of 2 μm is sequentially epitaxially grown by MOCVD epitaxy; the N-type heavily doped GaN ohmic contact layer 103 with the thickness of 2.5 μm is doped with Si with the doping concentration of 2.5 × 10¹⁸cm^-3(ii) a 20 periods of an InGaN/GaN multi-quantum well MQW absorption layer 104 which is not intentionally doped, wherein the thickness of an InGaN single layer is 5nm, and the thickness of a GaN single layer is 20 nm; a P-type doped GaN ohmic contact layer 105 with a thickness of 40nm, and is doped with Mg; and finally, annealing and activating the P-type doping to finish the epitaxial growth of the material.

Then, a semitransparent P-type ohmic contact electrode 106 with the thickness of 5nm is manufactured on the front surface of the whole structure by adopting electron beam evaporation, and the electrode material is Ni (2.5nm)/Au (2.5 nm); etching the mesa by adopting ICP (inductively coupled plasma) until the N-type heavily doped GaN ohmic contact layer 103 is exposed; depositing a layer of SiO with the thickness of 200nm by adopting PECVD technology₂The medium passivation layer 107, the medium passivation layer 107 plays the role of anti-reflection at the same time; etching a lead hole (not marked in the figure) by adopting wet chemical corrosion; and finally, manufacturing a Ti/Au N-type ohmic contact electrode 108 and a P-type contact Pad electrode 109 with the thickness of 2 microns by adopting electron beam evaporation.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention.

Claims

1. An MQW structure InGaN blue light detector is characterized in that: comprises that

A patterned sapphire substrate (101);

epitaxially growing an unintentionally doped GaN buffer layer (102) on the front surface of the patterned sapphire substrate (101);

an N-type heavily doped GaN ohmic contact layer (103) is epitaxially grown on the front surface of the unintended doped GaN buffer layer (102);

sequentially extending an InGaN/GaN multi-quantum well MQW absorption layer (104) on the front surface of the N-type heavily-doped GaN ohmic contact layer (103);

a P-type doped GaN ohmic contact layer (105) is epitaxially grown on the front surface of the InGaN/GaN multi-quantum well MQW absorption layer (104);

manufacturing a P-type ohmic contact electrode (106) on the P-type doped GaN ohmic contact layer (105);

a dielectric passivation layer (107) deposited on the front surface of the P-type ohmic contact electrode (106), wherein a lead hole capable of exposing the P-type ohmic contact electrode (106) is etched in the dielectric passivation layer (107);

an N-type ohmic contact electrode (108) and a P-type contact Pad electrode (109) manufactured at the position of a lead hole are arranged on the N-type heavily doped GaN ohmic contact layer (103), and the P-type contact Pad electrode (109) extends into the lead hole to be connected with the P-type ohmic contact electrode (106).

2. The MQW structure InGaN blue detector of claim 1, wherein: the In component of the InGaN/GaN multi-quantum well MQW absorption layer (104) is 0.05-0.3, the thickness of an InGaN single layer is 3nm-5nm, the thickness of a GaN single layer is 15nm-20nm, and the total thickness of the InGaN is set to be 100 nm.

3. The MQW structure InGaN blue detector of claim 1, wherein: the thickness of the P-type doped GaN ohmic contact layer (105) is 20nm-80 nm.

4. The MQW structure InGaN blue detector of claim 1, wherein: the P-type ohmic contact electrode (106) is a semitransparent electrode, the semitransparent electrode is a Ni/Au, Pt/Au or graphene electrode, and the total thickness of the electrode is less than or equal to 5 nm.

5. The MQW structure InGaN blue detector of claim 1, wherein: the medium passivation layer (107) is SiO₂And (3) a layer.