CN211480077U

CN211480077U - High-power flip LED chip with temperature monitoring function

Info

Publication number: CN211480077U
Application number: CN201922413456.1U
Authority: CN
Inventors: 张琦; 强愈高
Original assignee: Jiangsu Xinguanglian Technology Co ltd
Current assignee: Jiangsu Xinguanglian Technology Co ltd
Priority date: 2019-12-29
Filing date: 2019-12-29
Publication date: 2020-09-11
Anticipated expiration: 2029-12-29

Abstract

The utility model provides a high-power flip LED chip with temperature monitoring, which comprises a substrate layer; an N-GaN layer, a quantum well layer and a P-GaN layer are sequentially grown on the substrate layer; a reflecting layer is arranged on the P-GaN layer; the quantum well layer, the P-GaN layer and the reflecting layer are coated by the first insulating layer; an interconnection electrode layer is arranged on the first insulating layer; the interconnection electrode layer penetrates through the first insulating layer and is respectively connected with the reflecting layer and the N-GaN layer; the interconnection electrode layer is coated by the second insulating layer; the second insulating layer is provided with an extraction electrode layer; the extraction electrode layer comprises two pad electrodes which penetrate through the second insulating layer and are respectively connected with the interconnection electrode layer, and two thermal resistance monitoring electrodes which penetrate through the second insulating layer, the interconnection electrode layer, the first insulating layer, the reflecting layer, the P-GaN layer, the quantum well layer and the N-GaN layer and are respectively connected with the quantum well layer and the N-GaN layer; and a temperature detecting joint is formed at the joint of the two thermal resistance monitoring electrodes and the N-GaN layer. The utility model discloses realize the real time monitoring of LED chip junction temperature.

Description

High-power flip LED chip with temperature monitoring function

Technical Field

The utility model relates to a LED chip, especially a high-power flip-chip LED chip and preparation method with temperature monitoring.

Background

Under the application scene of the ultra-high power LED light source, because of the high-density integration characteristic, the temperature of the light source substrate and the lamp shell is only monitored, and whether the local overheating problem exists or not can not be effectively judged.

Local overheating often results in failure of one or more LED chips.

Disclosure of Invention

An object of the utility model is to overcome exist not enough among the prior art, provide a high-power flip-chip LED chip with temperature monitoring to and preparation method, set up a temperature probe festival that is used for monitoring chip junction temperature at the center of high-power LED chip, in order to realize the real time monitoring of LED chip junction temperature. The utility model adopts the technical proposal that:

the embodiment of the utility model provides a high-power flip LED chip with temperature monitoring, which comprises a substrate layer;

an N-GaN layer, a quantum well layer and a P-GaN layer are sequentially grown on the substrate layer;

a reflecting layer is arranged on the P-GaN layer; the quantum well layer, the P-GaN layer and the reflecting layer are coated by a first insulating layer;

an interconnection electrode layer is arranged on the first insulating layer; the interconnection electrode layer penetrates through the first insulating layer and is respectively connected with the reflecting layer and the N-GaN layer;

the interconnection electrode layer is coated by a second insulating layer;

an extraction electrode layer is arranged on the second insulating layer; the extraction electrode layer comprises two pad electrodes which penetrate through the second insulating layer and are respectively connected with the interconnection electrode layer, and two thermal resistance monitoring electrodes which penetrate through the second insulating layer, the interconnection electrode layer, the first insulating layer, the reflecting layer, the P-GaN layer, the quantum well layer and the N-GaN layer and are respectively connected with the quantum well layer and the N-GaN layer;

and a temperature detecting joint is formed at the joint of the two thermal resistance monitoring electrodes and the N-GaN layer.

Further, the connection position of the thermal resistance monitoring electrode and the N-GaN layer is positioned in the central area of the N-GaN layer.

Further, the metal layer of the interconnection electrode layer is Cr/Al/Ti/Pt/Au/Pt in sequence, wherein the thickness of Au is not less than 1 μm.

Furthermore, the metal layer of the extraction electrode layer is Cr/Al/Ti/Pt/Ni/Au/, wherein the thickness of Ni is not less than 300 nm.

The embodiment of the utility model also provides a preparation method of the high-power flip LED chip with temperature monitoring, which is characterized in that,

step 1, sequentially growing an N-GaN layer, a quantum well layer and a P-GaN layer on a substrate layer by using MOCVD equipment to form a complete LED epitaxial structure;

step 2, making a mask pattern by using a positive photoresist mask method, wherein a blank area on the mask pattern corresponds to a channel going to the N-GaN layer, and exposing the N-GaN layer corresponding to the blank area of the mask pattern;

step 3, manufacturing a reflection layer graph by using a negative photoresist mask method, and manufacturing a reflection layer by using a magnetron sputtering process, wherein the reflection layer is provided with a channel for going to the N-GaN layer;

step 4, preparing a first insulating layer on the surface of the wafer by utilizing a PECVD (plasma enhanced chemical vapor deposition) process, manufacturing a corrosion pattern by a positive photoresist mask method, and then carrying out through hole corrosion on the first insulating layer to form a channel for going to the N-GaN layer and a channel for going to the reflecting layer;

step 5, manufacturing an interconnection electrode pattern by using a negative photoresist masking method, and manufacturing an interconnection electrode layer by using electron beam evaporation equipment, wherein the interconnection electrode layer penetrates through the first insulating layer and is respectively connected with the reflecting layer and the N-GaN layer; a channel going to the N-GaN layer is reserved on the interconnection electrode layer;

step 6, preparing a second insulating layer on the surface of the wafer by utilizing the PECVD process again, manufacturing a corrosion pattern by a positive photoresist mask method, and performing through hole corrosion on the second insulating layer to form a channel for going to the N-GaN layer and a channel for going to the interconnected electrode layer;

step 7, manufacturing an extraction electrode pattern by using a negative photoresist mask method again, and extracting an electrode layer by using electron beam evaporation equipment;

the extraction electrode layer comprises two pad electrodes and two thermal resistance monitoring electrodes; wherein the two pad electrodes penetrate through the second insulating layer and are respectively connected with the interconnection electrode layer; the two thermal resistance monitoring electrodes penetrate through the second insulating layer, the interconnection electrode layer, the first insulating layer, the reflecting layer, the P-GaN layer and the quantum well layer and are respectively connected with the N-GaN layer.

Further, the metal of the reflecting layer is Ag/TiW.

Further, the first insulating layer is a SiO2/SiNx insulating layer.

Further, the second insulating layer is an SiO2/SiNx insulating layer.

The utility model has the advantages that: the utility model discloses an utilize the negative temperature characteristic of N-GaN impedance, set up a temperature detecting festival that is used for monitoring LED chip junction temperature at high-power flip-chip LED chip center, realize the real time monitoring of LED chip junction temperature, cooperate the drive circuit design again, can adjust drive current in real time monitoring chip junction temperature, solve the local overheated difficult problem that loses efficacy of high-power light source.

Drawings

Fig. 1 is one of the cross-sectional views of the present invention.

Fig. 2 is a second cross-sectional view of the present invention.

Fig. 3 is a schematic diagram of the present invention etching and exposing the N-GaN layer.

Fig. 4 is a schematic diagram of the present invention for fabricating a reflective layer.

Fig. 5 is a schematic diagram of manufacturing a first insulating layer according to the present invention.

Fig. 6 is a schematic diagram of manufacturing an interconnection electrode layer according to the present invention.

Fig. 7 is a schematic diagram of the present invention for preparing a second insulating layer.

Fig. 8 is a schematic diagram of the present invention for manufacturing the extraction electrode layer.

Detailed Description

The invention is further described with reference to the following specific drawings and examples.

The embodiment of the utility model provides a preparation method of high-power flip-chip LED chip with temperature monitoring, in the following method, the wafer indicates the LED chip unfinished structure of the middle step;

the method comprises the following steps:

step 1, sequentially growing an N-GaN layer 2, a quantum well layer 3 and a P-GaN layer 4 on a sapphire substrate layer 1 by using MOCVD equipment to form a complete LED epitaxial structure;

the light emitting wavelength can be changed by changing the temperature and the In and Al compositions In the growth process of the quantum well layer 3;

step 2, making a mask pattern by using a positive photoresist mask method, wherein the blank area on the mask pattern corresponds to the channel of the N-GaN layer 2, and exposing the N-GaN layer 2 corresponding to the blank area of the mask pattern by using an ICP (inductively coupled plasma) etching method;

FIG. 3 shows the mask pattern of this step with blank regions 13;

step 3, utilizing a negative photoresist mask method to manufacture a reflection layer pattern, and manufacturing a reflection layer 5 through a magnetron sputtering process, wherein a channel for going to the N-GaN layer 2 is arranged on the reflection layer 5;

the metal of the reflecting layer is generally Ag/TiW, and a channel 501 leading to the N-GaN layer 2 is formed on the reflecting layer 5 in FIG. 4;

step 4, preparing a first insulating layer 6 on the surface of the wafer by utilizing a PECVD (plasma enhanced chemical vapor deposition) process, manufacturing a corrosion pattern by a positive photoresist mask method, and performing through hole corrosion on the first insulating layer 6 by using a BOE (biaxially oriented film) solution to form a channel 601 for going to the N-GaN layer 2 and a channel 602 for going to the reflecting layer 5; as shown in fig. 5;

the first insulating layer 6 is a SiO2/SiNx insulating layer;

step 5, manufacturing an interconnection electrode pattern by using a negative photoresist masking method, and manufacturing an interconnection electrode layer 7 by using electron beam evaporation equipment, wherein the interconnection electrode layer 7 penetrates through the first insulating layer 6 and is respectively connected with the reflecting layer 5 and the N-GaN layer 2; a channel 701 towards the N-GaN layer 2 is left on the interconnection electrode layer 7; as shown in fig. 6;

the metal layer of the interconnection electrode layer 7 is sequentially Cr/Al/Ti/Pt/Au/Pt, wherein the thickness of Au is not less than 1 μm;

step 6, preparing a second insulating layer 8 on the surface of the wafer by using the PECVD process again, manufacturing a corrosion pattern by using a positive photoresist mask method, and performing through hole corrosion on the second insulating layer 8 by using a BOE solution to form a channel 801 for going to the N-GaN layer 2 and a channel 802 for going to the interconnection electrode layer 7; as shown in fig. 7;

the second insulating layer 8 is a SiO2/SiNx insulating layer;

the extraction electrode layer comprises two

pad electrodes

9 and 10 and two thermal

resistance monitoring electrodes

11 and 12; two

pad electrodes

9 and 10 penetrate through the second insulating layer 8 and are respectively connected with the interconnection electrode layer 7; the two thermal

resistance monitoring electrodes

11 and 12 penetrate through the second insulating layer 8, the interconnection electrode layer 7, the first insulating layer 6, the reflecting layer 5, the P-GaN layer 4 and the quantum well layer 3 and are respectively connected with the N-GaN layer 2;

the metal layer of the leading-out electrode layer is sequentially Cr/Al/Ti/Pt/Ni/Au/, wherein the thickness of Ni is not less than 300 nm;

the subsequent steps may further include:

step 8, thinning the wafer garden to 100-200 mu m;

and 9, cutting the wafer to separate to obtain a single LED chip.

Through the process steps of the embodiment, the high-power flip LED chip with the temperature monitoring function is obtained, and comprises a substrate layer 1, wherein an N-GaN layer 2, a quantum well layer 3 and a P-GaN layer 4 are sequentially grown on the substrate layer 1;

a reflecting layer 5 is arranged on the P-GaN layer 4; the quantum well layer 3, the P-GaN layer 4 and the reflecting layer 5 are coated by a first insulating layer 6;

an interconnection electrode layer 7 is arranged on the first insulating layer 6; the interconnection electrode layer 7 penetrates through the first insulating layer 6 and is respectively connected with the reflecting layer 5 and the N-GaN layer 2;

the interconnection electrode layer 7 is coated by a second insulating layer 8;

an extraction electrode layer is arranged on the second insulating layer 8; the extraction electrode layer comprises two

pad electrodes

9 and 10 which penetrate through the second insulating layer 8 and are respectively connected with the interconnection electrode layer 7, and two thermal

resistance monitoring electrodes

11 and 12 which penetrate through the second insulating layer 8, the interconnection electrode layer 7, the first insulating layer 6, the reflecting layer 5, the P-GaN layer 4, the quantum well layer 3 and the N-GaN layer 2 and are respectively connected;

and a temperature detecting joint is formed at the joint of the two thermal

resistance monitoring electrodes

11 and 12 and the N-GaN layer.

More preferably, the thermal

resistance monitor electrodes

11, 12 are connected to the N-GaN layer at positions in the central region of the N-GaN layer.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the scope of the claims of the present invention.

Claims

1. A high-power flip-chip LED chip with temperature monitoring comprises a substrate layer (1) and is characterized in that,

an N-GaN layer (2), a quantum well layer (3) and a P-GaN layer (4) are sequentially grown on the substrate layer (1);

a reflecting layer (5) is arranged on the P-GaN layer (4); the quantum well layer (3), the P-GaN layer (4) and the reflecting layer (5) are coated by a first insulating layer (6);

an interconnection electrode layer (7) is arranged on the first insulating layer (6); the interconnection electrode layer (7) penetrates through the first insulating layer (6) and is respectively connected with the reflecting layer (5) and the N-GaN layer (2);

the interconnection electrode layer (7) is coated by a second insulating layer (8);

an extraction electrode layer is arranged on the second insulating layer (8); the extraction electrode layer comprises two pad electrodes (9 and 10) which penetrate through the second insulating layer (8) and are respectively connected with the interconnection electrode layer (7), and two thermal resistance monitoring electrodes (11 and 12) which penetrate through the second insulating layer (8), the interconnection electrode layer (7), the first insulating layer (6), the reflecting layer (5), the P-GaN layer (4) and the quantum well layer (3) and are respectively connected with the N-GaN layer (2);

the two thermal resistance monitoring electrodes (11, 12) are connected with the N-GaN layer to form a temperature detecting node.

2. The high power flip LED chip with temperature monitoring of claim 1,

the thermal resistance monitoring electrode is connected with the N-GaN layer at the position of the central region of the N-GaN layer.

3. The high power flip LED chip with temperature monitoring of claim 1,

the metal layer of the interconnection electrode layer (7) is Cr/Al/Ti/Pt/Au/Pt in sequence, wherein the thickness of Au is not less than 1 μm.

4. The high power flip LED chip with temperature monitoring of claim 1,

the metal layer of the extraction electrode layer is sequentially Cr/Al/Ti/Pt/Ni/Au, wherein the thickness of Ni is not less than 300 nm.