CN102651432A

CN102651432A - Method for preparing thin film type LED

Info

Publication number: CN102651432A
Application number: CN2012101521064A
Authority: CN
Inventors: 李喜峰; 李倩; 王万晶; 张建华
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2012-05-17
Filing date: 2012-05-17
Publication date: 2012-08-29

Abstract

The invention discloses a method for preparing a thin film type LED (light emitting diode). The method comprises the steps that an intrinsic GaN layer, an n-shaped GaN layer, a multiple quantum well layer and a p-shaped GaN layer are deposited on a sapphire substrate by using the conventional Metal organic vapor phase epitaxy method; when a transparent current diffusion layer GZO thin film is prepared, a sol-gel pulling method is adopted, and according to the sol-gel pulling method the method, devices are simple, and the production cost is low; and finally, a complete chip structure can be realized by using an argon ion dry etching method. The green and synthetic method for preparing a film is adopted for preparing film type LED devices, so that the cost is low, the pollution is small, and the implementation is easy.

Description

A kind of method of thin-film type LED preparation

Technical field

The present invention relates to a kind of preparation method of thin-film type LED, relate in particular to the method that a kind of gel sol method prepares the LED current-diffusion layer, belong to semiconductor chip and make the field.

Technical background

In traditional LED preparation method, on Sapphire Substrate, adopt metal organic facies epitaxy method deposit film usually, complex equipments, technology is loaded down with trivial details, produce old higher.

Summary of the invention

The objective of the invention is to provides a kind of method for preparing thin-film type LED to the defective that prior art exists.This method is a sol-gal process; Sol-gal process has many advantages as a kind of green synthesis method for preparing film compared with traditional method for manufacturing thin film: device simple, and technology is simple; Production cost is low; Stoichiometric proportion is easy to control, and production procedure is simple, does not require vacuum, hot environment etc.Prepared by Sol Gel Method LED transparency electrode has the important use meaning in the semiconductor chip fabrication industry.

For reaching above purpose, the present invention adopts following technical proposals:

A kind of method for preparing thin-film type LED is characterized in that step of preparation process is following:

A. the growth of sapphire epitaxial wafer:

On Sapphire Substrate, adopt metal organic facies epitaxial deposition method growing low temperature gallium nitride GaN layer successively, intrinsic GaN layer, n type GaN layer, SQW (MQW) layer and P type GaN layer.

B. the cleaning of sapphire epitaxial wafer:

With sapphire epitaxial wafer ultrasonic cleaning 10 ± 1 min in isopropyl alcohol and acetone successively; Deionized water rinsing; In mixed acid solution (sulfuric acid: hydrogen peroxide solution: the ratio of deionized water is classified 5:5:1 as), soak at room temperature 15 ± 1 min; Again in dilute hydrochloric acid solution (volume fraction is 20%), soak at room temperature 5 ± 0.5 min; Use deionized water ultrasonic cleaning 10 ± 1 min at last; Nitrogen dries up.

C. adopt the collosol and gel czochralski method, zinc oxide (GZO) film that the current-diffusion layer-gallium of preparation LED device mixes, the concrete operations step is following:

(1) at first in the glass beaker of a 200 ± 20ml; The 2 water acetic acid zinc of 0.045 ± 0.002mol and the 5.5 nitric hydrate galliums of 0.0006 ± 0.0001mol are put into beaker; The absolute methanol of 150 ± 10ml is poured in the beaker, dropwise added the MEA of 0.045 ± 0.002mol again.Magnetic agitation is to whole dissolvings, and 60 ± 5 ℃ of water-baths also are incubated 1 ± 0.2 hour under the situation of magnetic agitation.Temperature is brought up to 70 ~ 100 ℃, and to carry out solvent evaporation be 20 ~ 80% of original liquor capacity up to the volume of surplus solution.Room-temperature aging 6 ± 0.2 hours, refrigerator cold-storage 42 ± 0.5 hours forms colloidal sol.

(2) preparation of current-diffusion layer Ga-doped zinc oxide film

At room temperature, at the up membrane of jewel epitaxial wafer: after soaking into 1 ± 0.1min, lift with the speed of 65 ± 5mm/min.Whenever lifted after the skim, film has been toasted 30 ± 0.5min under infrared lamp, carried out 500 ± 50 ℃ of short annealing 15 ± 0.5min again, accomplished the drying course that lifts of a film.Repeat above step 6 time again, the zinc-oxide film that mixes with the gallium that reaches certain thickness (200nm).At last with film timeliness two days, 600 ± 50 ℃ of vacuum annealing 1 ± 0.1h.

(3) adopt Ar ion dry etching current-diffusion layer, finally promptly obtain complete LED device.The present invention has realized the method for a kind of novel LED of preparation through adopting the current-diffusion layer in the Prepared by Sol Gel Method LED device.

The present invention compared with prior art has following conspicuous outstanding substantive distinguishing features and marked improvement:

The preparation of current-diffusion layer of the present invention, the cost of material of use is cheaper, and use equipment is simple, and is easy to operate.In semiconductor chip manufacturing field important use is arranged.

Description of drawings

Fig. 1 is the structure of led chip.

Fig. 2 is the LED luminous photo.

Embodiment

After specific embodiment of the present invention being described at present.

Embodiment

The preparation process of this thin-film type LED is described below:

1) growth of sapphire epitaxial wafer

A. going up employing metal organic facies epitaxial deposition low temperature gallium nitride (GaN) layer (2) in Sapphire Substrate (1),

B. adopt metal organic facies epitaxial deposition each the 1 μ m of intrinsic GaN layer (3) and n type GaN layer (4) that grows successively.

C. adopting metal organic facies epitaxial deposition MQW (MQW) layer (6) of growing successively respectively is 200nm with P type GaN layer (7) thickness

2) cleaning of sapphire epitaxial wafer

3) adopt the collosol and gel czochralski method, zinc oxide (GZO) film (8) that the current-diffusion layer-gallium of preparation LED device mixes, the concrete operations step is following:

(2) preparation of current-diffusion layer Ga-doped zinc oxide film

At room temperature, at the up membrane of jewel epitaxial wafer: after soaking into 1 ± 0.1min, lift with the speed of 65 ± 5mm/min.Whenever lifted after the skim, film has been toasted 30 ± 0.5min under infrared lamp, carried out 500 ± 50 ℃ of short annealing 15 ± 0.5min again, accomplished the drying course that lifts of a film.Repeat above step 6 time again, the zinc-oxide film (8) that mixes with the gallium that reaches certain thickness (200nm).At last with film timeliness two days, 600 ± 50 ℃ of vacuum annealing 1 ± 0.1h.

(3) adopt Ar ion dry etching current-diffusion layer, finally promptly obtain complete LED device.

Instrument detecting

Prepared sample structure of the foregoing description and luminous result are shown among Fig. 1 and Fig. 2 of accompanying drawing.

Claims

1. the method for thin-film type LED preparation is characterized in that step of preparation process is following:

A. the growth of sapphire epitaxial wafer:

Go up employing metal organic facies epitaxy method in Sapphire Substrate (1) and deposit low temperature gallium nitride GaN layer (2) successively, intrinsic GaN layer (3), n type GaN layer (4), SQW mqw layer (6) and P type GaN layer (2);

B. the cleaning of sapphire epitaxial wafer:

With sapphire epitaxial wafer ultrasonic cleaning 10 ± 1 min in isopropyl alcohol and acetone successively; Deionized water rinsing; At mixed acid solution--sulfuric acid: hydrogen peroxide solution: the ratio of deionized water is classified as among the 5:5:1, soak at room temperature 15 ± 1 min; Again at dilute hydrochloric acid solution--volume fraction is in 20%, soak at room temperature 5 ± 0.5 min; Use deionized water ultrasonic cleaning 10 ± 1min at last; Nitrogen dries up;

C. adopt the collosol and gel czochralski method, the zinc oxide GZO film (8) that the current-diffusion layer-gallium of preparation LED device mixes, the concrete operations step is following:

(1) at first in the glass beaker of a 200 ± 20ml; The 2 water acetic acid zinc of 0.04 ± 0.002mol and the 5.5 nitric hydrate galliums of 0.0006 ± 0.0001mol are put into beaker; The absolute methanol of 150 ± 10ml is poured in the beaker, dropwise added the MEA of 0.045 ± 0.002mol again; Magnetic agitation is to whole dissolvings, and 60 ± 5 ℃ of water-baths also are incubated 1 ± 0.2 hour under the situation of magnetic agitation; Temperature is brought up to 70 ~ 100 ℃, and to carry out solvent evaporation be 20 ~ 80% of original liquor capacity up to the volume of surplus solution; Room-temperature aging 6 ± 0.2 hours, refrigerator cold-storage 42 ± 0.5 hours forms colloidal sol;

(2) preparation of current-diffusion layer Ga-doped zinc oxide film (8):

At room temperature, at the up membrane of sapphire epitaxial wafer: after soaking into the colloidal sol 1 ± 0.1min that in step (1), prepares, lift with the speed of 65 ± 5mm/min; Whenever lifted after the skim, film has been toasted 30 ± 0.5min under infrared lamp, carried out 500 ± 50 ℃ of short annealing 15 ± 0.5min again, accomplished the drying course that lifts of a film; Repeat above step 6 time again, the zinc-oxide film (8) that mixes with the gallium that reaches 200 ± 20nm thickness, at last with film timeliness two days, 600 ± 50 ℃ of vacuum annealing 1 ± 0.1h;