CN103177969A

CN103177969A - Preparation method of metallic oxide thin film transistor

Info

Publication number: CN103177969A
Application number: CN2013100589219A
Authority: CN
Inventors: 李倩; 李喜峰; 信恩龙; 张建华
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2013-02-26
Filing date: 2013-02-26
Publication date: 2013-06-26

Abstract

The invention discloses a preparation method of a metallic oxide thin film transistor. The preparation method includes: growing a first conducting layer on an insulating substrate, and photoetching to obtain a gate electrode; growing an insulating layer on the gate electrode; coating an active layer, and photoetching to obtain an active island; and depositing a second conducting layer, and photoetching to obtain a source electrode and a leakage electrode. By irradiating thin films prepared by a solution method, heat treatment temperature of the thin films can be lowered evidently, and metallic oxide can be formed at low temperature.

Description

A kind of preparation method of metal oxide thin-film transistor

Technical field

The present invention relates to a kind of preparation method of metal oxide thin-film transistor, belong to the photoelectric display technical field.

Background technology

Thin-film transistor (TFT) is having a wide range of applications as the core switching element of active matrix display spare.The TFT of at present business flat panel display extensive use is amorphous silicon hydride TFT(a-Si:H TFT), a-Si:H TFT is easy large tracts of land deposition at low temperatures, but due to the character of material itself, the lower (＜1cm of its mobility ²V ^-1s ^-1), hindered the development of later high-performance flat panel display.Polysilicon membrane crystal (Poly-Si TFT) is although the pipe mobility is higher, and due to its complex process, low temperature process is difficult to realize, has also limited the application of Poly-Si TFT.Along with the development of AM-OLED and the demand of flexible display technologies, need a kind of mobility higher, and the active layer semi-conducting material that can prepare at low temperatures, oxide thin film transistor is as a kind of novel electron device, but have that mobility is high, uniformity is strong, transmitance is good and the excellent performance such as low temperature making, obtain extensive concern, in the flat panel display industry, huge application prospect is arranged, become large scale, high resolution A M-OLED (active matrix organic light-emitting diode) demonstration and the flexible best candidate that shows.

Traditional preparation method of metal-oxide film is based upon on traditional vacuum technology of preparing, and vacuum technique equipment is complicated, is unfavorable for the large tracts of land modern production.The solution rule is shown one's talent under this background, and the solwution method apparatus and process is simple, can realize streamline large-scale production, is the promising film production method of tool very.But, due to the preparation characteristic of solwution method self, need to carry out 300 ℃ of high annealing heat treatments (〉 to the film of preparation) and to obtain required sull.And at present, flexible base, board (as plastic base) can not bear the temperature more than 300 ℃, and therefore, how reducing the annealing temperature that solwution method prepares film is a research emphasis.

Summary of the invention

For the defective that prior art exists, the purpose of this invention is to provide a kind of preparation method of metal oxide thin-film transistor, grow successively gate electrode, insulating barrier, active layer and source-drain electrode on insulated substrate.

For achieving the above object, the present invention adopts following technical scheme:

A kind of preparation method of metal oxide thin-film transistor has following step:

1) deposition the first conductive layer on insulated substrate, be coated with photoresist on described the first conductive layer; Utilize the first mask plate, by exposure, etching and peel off the formation gate electrode;

2) depositing insulating layer on described gate electrode;

3) the required solution of preparation active layer, according to preparing oxide, choose suitable raw material, solvent and stabilizer; Adopt the solution film preparation method to prepare active layer on described insulating barrier;

4) adopt the ultraviolet LED lamp to carry out photo-irradiation treatment to active layer, under the bringing out of ultraviolet photon, form oxide and follow product; Follow the product volatilization to obtain fine and close metal-oxide film, obtain the oxide active layer;

5) be coated with photoresist on described oxide active layer; Utilize the second mask plate, by exposure, development, etching and peel off and form oxide active layer island;

6) deposition the second conductive layer on described oxide active layer island, be coated with photoresist on described the second conductive layer, utilizes the 3rd road mask plate, forms source electrode and drain electrode by exposure, development, etching, makes metal oxide thin-film transistor.

Above-mentioned steps 3) the solution film preparation method in is spin coating, lifts or inkjet printing.

Above-mentioned steps 4) the ultraviolet LED lamp emission wavelength in is 192 to 365nm.Light application time is 20-120 minute.

Principle of the present invention is as follows:

(1)

(2)

As shown in (1) formula, for raw material are put into, the signal equation that hydrolysis condensation reaction forms presoma occurs in solvent.Under illumination condition, have strong energy photon ( hν) impel the presoma formation metal oxide that reacts, as shown in (2) formula.

Compared with prior art, the present invention has advantages of following giving prominence to:

Adopt illumination that the film of solwution method preparation is processed, can obviously reduce the heat treatment temperature of film, can realize that low temperature forms metal oxide.

Description of drawings

Fig. 1 the first conductive layer schematic diagram.

Fig. 2 gate electrode schematic diagram.

Fig. 3 insulating barrier schematic diagram.

Fig. 4 active layer schematic diagram.

Fig. 5 active layer illumination schematic diagram.

Fig. 6 oxide active layer schematic diagram.

Fig. 7 oxide active layer island schematic diagram.

Fig. 8 the second conductive layer schematic diagram.

Fig. 9 source-drain electrode pattern schematic diagram.

Figure 10 TFT transfer characteristic curve.

Embodiment

Below in conjunction with Figure of description, embodiments of the present invention are done more detailed description; the present embodiment is implemented under take technical solution of the present invention as prerequisite; provided detailed execution mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

As Fig. 1-shown in Figure 9, a kind of preparation method of metal oxide thin-film transistor has following step:

1) adopt radio-frequency magnetron sputter method to form the first conductive layer 102 on the glass substrate 101 that cleaned, be coated with photoresist on described the first conductive layer 102; Utilize the first mask plate, by exposure, etching and peel off and form gate electrode 102a;

2) adopt ion beam enhanced chemical vapour deposition technique depositing insulating layer 103 on described gate electrode 102a;

3) obtain solution, in the present embodiment, preparation indium gallium zinc oxide, adopt zinc acetate, and gallium nitrate, indium nitrate are done respectively the zinc source, gallium source and indium source, employings EGME is solvent, monoethanolamine is stabilizer, prepares the required precursor solution of active layer; Adopt spin-coating method on described insulating barrier 103,2 ± 1 layers of spin coatings, obtaining thickness is the active layer 104 of 60 ± 20nm;

4) adopt the ultraviolet LED lamp to carry out photo-irradiation treatment to active layer 104, the employing emission wavelength be 192 ± 10nm, 245 ± 10nm, 303 ± 10nm, 365 ± 10nm the ultraviolet LED lamp respectively or combination the indium gallium zinc oxide film of 106 spin coatings was carried out illumination heat treatment 20-120 minute, under the bringing out of ultraviolet photon, form oxide and follow product; Follow the product volatilization to obtain fine and close metal-oxide film, obtain oxide active layer 104a; Assist the formation metal-oxide film in order to reduce the processing time by suitable heating.

5) be coated with photoresist on described oxide active layer 104a; Utilize the second mask plate, by exposure, development, etching and peel off and form indium gallium zinc oxide active layer island 104b;

6) adopt radio-frequency magnetron sputter method deposition the second conductive layer 107 on described indium gallium zinc oxide active layer island 104b, be coated with photoresist on described the second conductive layer 107, utilize the 3rd road mask plate, form source electrode 107a and drain electrode 107b by exposure, development, etching, make metal oxide thin-film transistor.

Through above step, adopt solwution method low temperature to prepare metal oxide thin-film transistor, the transfer characteristic curve of the TFT of acquisition is as shown in figure 10.As can be seen from Figure 10, along with the variation of gate voltage, TFT device source leakage current changes, and shows that grid voltage can be good at controlling source-drain current, has obvious TFT transfer characteristic, confirms that further the method can be used to prepare the TFT device.

Claims

1. the preparation method of a metal oxide thin-film transistor, is characterized in that, has following step:

1) at the upper deposition of insulated substrate (101) the first conductive layer (102), at the upper coating of described the first conductive layer (102) photoresist; Utilize the first mask plate, by exposure, etching and peel off and form gate electrode (102a);

2) at the upper depositing insulating layer (103) of described gate electrode (102a);

3) the required solution of preparation active layer, according to preparing oxide, choose suitable raw material, solvent and stabilizer; Prepare active layer (104) at the upper solution film preparation method that adopts of described insulating barrier (103);

4) adopt ultraviolet LED lamp (106) to carry out photo-irradiation treatment to active layer (104), under the bringing out of ultraviolet photon, form oxide and follow product; Follow the product volatilization to obtain fine and close metal-oxide film, obtain oxide active layer (104a);

5) at the upper coating of described oxide active layer (104a) photoresist; Utilize the second mask plate, by exposure, development, etching and peel off and form oxide active layer island (104b);

6) upper deposition the second conductive layer (107) on described oxide active layer island (104b), at the upper coating of described the second conductive layer (107) photoresist, utilize the 3rd road mask plate, form source electrode (107a) and drain electrode (107b) by exposure, development, etching, make metal oxide thin-film transistor.

2. the preparation method of a kind of metal oxide thin-film transistor according to claim 1, is characterized in that, the solution film preparation method in described step 3) is spin coating, lifts or inkjet printing.

3. the preparation method of a kind of metal oxide thin-film transistor according to claim 1, is characterized in that, the ultraviolet LED lamp emission wavelength in described step 4) is 192 to 365 nanometers, and light application time is 20-120 minute.