CN102709433B

CN102709433B - Method for manufacturing GaN-based light-emitting diode (LED) mesh electrode

Info

Publication number: CN102709433B
Application number: CN201210174972.3A
Authority: CN
Inventors: 王家鑫; 吴奎; 曾一平
Original assignee: Institute of Semiconductors of CAS
Current assignee: SHANXI ZHONGKE ADVANCED ULTRAVIOLET OPTOELECTRONICS TECHNOLOGY Co.,Ltd.
Priority date: 2012-05-30
Filing date: 2012-05-30
Publication date: 2014-08-06
Anticipated expiration: 2032-05-30
Also published as: CN102709433A

Abstract

The invention discloses a method for manufacturing a GaN-based light-emitting diode (LED) mesh electrode. The method comprises the following steps of: 1) evaporating an indium tin oxide (ITO) film on the surface of a GaN-based epitaxial wafer; 2) arranging a single layer of closely arranged self-assembled spheres on the surface of the ITO film; 3) performing heating to firmly combine the self-assembled spheres and the ITO film; 4) etching the self-assembled spheres by using an inductively coupled plasma (ICP) method, wherein intervals between the etched self-assembled spheres are increased, and the radiuses of the etched self-assembled spheres are decreased; 5) performing reheating to slightly sink the self-assembled spheres into the surface of the ITO film to change point contact into surface contact; 6) evaporating metal on the surfaces of the self-assembled spheres, in gaps between the self-assembled spheres and on the surface of the ITO film; 7) removing the metal from the surfaces of the self-assembled spheres by using a toluene ultrasonic method, and reserving the metal on the surface of the ITO film; and 8) performing high-temperature treatment to gasify the self-assembled spheres and enable the metal on the surface of the ITO film to form the mesh electrode to finish the manufacture of the mesh electrode. The method has the advantages of high electrode contact resistance, high transmittance, high luminous efficiency and uniform current distribution.

Description

The manufacture method of GaN base LED mesh electrodes

Technical field

The invention belongs to technical field of semiconductors, refer to especially a kind of manufacture method of GaN base LED mesh electrodes.

Background technology

Light-emitting diode is energy saving and environment friendly light source, has that volume is little, the response time is short, luminous efficiency is high, the life-span is long, is widely used in illumination and demonstration field.The research of GaN base LED, to significant from optical illumination, obtains very large attention rate.In the manufacture craft process of LED, the making of electrode exists that contact resistance is large, transmitance is low conventionally, causes the problem of the aspects such as the low and CURRENT DISTRIBUTION of light extraction efficiency is inhomogeneous, has limited the raising of LED power output.

Summary of the invention

The object of the invention is to, a kind of manufacture method of GaN base LED mesh electrodes is provided, it is to form mesh electrodes on the ITO film of GaN base epitaxial wafer, can obtain good current expansion uniformity, improves light extraction efficiency.

The manufacture method that the invention provides a kind of GaN base LED mesh electrodes, comprises the following steps:

1) at the surperficial evaporation ITO film of GaN base epitaxial wafer;

2) at the compact arranged self assembly ball of surface alignment one individual layer of ITO film;

3) heating, makes self assembly ball be combined firmly with ITO film;

4) adopt ICP method, etching self assembly ball, after over etching, it is large that self assembly sphere gap becomes, and the radius of a ball reduces;

5) heat again, make self assembly ball have a little and subside on ITO film surface, a contact is become to face contact;

6) in the surface of self assembly ball, gap and the surperficial evaporation metal of ITO film;

7) adopt toluene ultrasonic method, remove the metal on self assembly ball surface, retain ITO film surface metal;

8) high-temperature process, makes the gasification of self assembly ball, makes the metal on ITO film surface form mesh electrode, completes the making of mesh electrodes.

Brief description of the drawings

For making those skilled in the art can further understand structure of the present invention, feature and object thereof, below in conjunction with being described in detail as follows of accompanying drawing and preferred embodiment, wherein:

Fig. 1 is the structural representation of GaN base LED epitaxial wafer of the present invention and ITO film;

Fig. 2 is that the present invention makes the vertical view after self assembly ball;

Fig. 3 is that self assembly ball of the present invention covers the sectional view on ITO film;

Fig. 4 is that the present invention adopts the sectional view after ICP etching self assembly ball;

Fig. 5 is that the present invention steams the sectional view after metal at self assembly sphere gap and ITO film surface;

Fig. 6 is that high temperature of the present invention is removed the sectional view after self assembly ball.

Embodiment

Refer to shown in Fig. 1 to Fig. 6, the invention provides a kind of manufacture method of GaN base LED mesh electrodes, comprise the following steps:

1) at the surperficial evaporation ITO film 11 of GaN base epitaxial wafer 10, can be also other AZO herein, PET conductive film;

2) at the compact arranged self assembly ball 20 of surface alignment one individual layer of ITO film 11, the material of described self assembly ball 20 is polystyrene or silica, waits organic polymer ball, and the diameter of ball is 0.5-1um (consulting Fig. 2);

3) heating, makes self assembly ball 20 firm with 11 combinations of ITO film, and the temperature of described heating is 80 DEG C;

4) adopt ICP method, etching self assembly ball 20, after over etching, self assembly ball 20 spacing become large, and the radius of a ball reduces, and described etching gas is oxygen, the starter power of 300W, 10W etching power, etch period is 1-2min;

5) heat again, make self assembly ball 20 have a little on ITO film 11 surfaces subside (consulting Fig. 4), a contact is become to face contact, the described temperature of heating is again 105 DEG C, and the time is 15min;

6) in the surface of self assembly ball 20, gap and the surperficial evaporation metal 50 of ITO film 11, this metal 50 is Ni and Au, and the thickness of Ni is 1-5nm, and the thickness of Au is 1050nm; Or Ni \ Ag \ Pt \ Au, other metal electrode system such as Cr \ Pt \ Au etc.

7) adopt toluene ultrasonic method, remove the metal 50 on self assembly ball 20 surfaces, retain ITO film 11 surface metals 50, the time of described toluene ultrasonic method processing is 46min;

8) high-temperature process, gasifies self assembly ball 20, makes the metal 50 on ITO film 11 surfaces form mesh electrode, and the temperature of described high-temperature process is 500-600 DEG C, and the time is 25-35min, completes the making of mesh electrodes.

The above; be only the embodiment in the present invention, but protection scope of the present invention is not limited to this, any people who is familiar with this technology is in the disclosed technical scope of the present invention; the conversion that can expect easily or replacement, all should be encompassed in of the present invention comprise scope within.Therefore, protection scope of the present invention should be as the criterion with the protection range of claims.

Claims

1. a manufacture method for GaN base LED mesh electrodes, comprises the following steps:

1) at the surperficial evaporation ITO film of GaN base epitaxial wafer;

3) heating, makes self assembly ball be combined firmly with ITO film;

4) adopt ICP method, etching self assembly ball, after over etching, it is large that self assembly sphere gap becomes, and the radius of a ball reduces, described employing ICP method, etching gas is oxygen, the starter power of 300W, 10W etching power, etch period is 1-2min;

6) in the surface of self assembly ball, gap and the surperficial evaporation metal of ITO film, the metal of described evaporation is Ni and Au, and the thickness of Ni is 1-5nm, and the thickness of Au is 10-50nm;

8) employing temperature is the high-temperature process of 500-600 DEG C, makes the gasification of self assembly ball, makes the metal on ITO film surface form mesh electrode, completes the making of mesh electrodes.

2. the manufacture method of GaN base LED mesh electrodes according to claim 1, wherein step 2)the material of described self assembly ball is polystyrene, or silica organic polymer ball, and the diameter of ball is 0.5-1um.

3. the manufacture method of GaN base LED mesh electrodes according to claim 1, wherein the temperature of heating is 80 DEG C.

4. the manufacture method of GaN base LED mesh electrodes according to claim 1, wherein the temperature of heating is 105 DEG C again, the time is 1-5min.

5. the manufacture method of GaN base LED mesh electrodes according to claim 1, the time that wherein adopts toluene ultrasonic method is 4-6min.

6. the manufacture method of GaN base LED mesh electrodes according to claim 1, wherein the time of high-temperature process is 25-35min.