CN101859858A - Graphene-based transparent conductive electrode and its preparation method and application - Google Patents

Abstract

The invention discloses a transparent conductive electrode using a graphene film as a GaN-based LED and an ultraviolet detector and its preparation method and application. The graphene film is solidified and bonded to the surface of the GaN substrate of the LED and the ultraviolet detector. Prepare graphene transparent conductive film by chemical vapor deposition or reduction oxidation method, and use micromachining lithography, etching and metal deposition to make GaN-based LED and ultraviolet detector; transfer graphene film to LED or ultraviolet detector On the p-type GaN substrate, instead of ITO or Ni/Au as a transparent conductive electrode. The invention adopts the graphene thin film as the transparent conductive electrode, can realize low-cost, high-brightness light-emitting devices, and expands the application of carbon nanomaterials in the field of GaN-based photoelectric devices.

Description

Graphene-based transparent conductive electrode and its preparation method and application

technical field

The invention relates to a GaN-based LED, a transparent conductive electrode of an ultraviolet light detector and a manufacturing method thereof. The manufacturing process includes preparing a graphene film, transferring the graphene film to a P-type GaN substrate, and micromachining the detector. A transparent conductive electrode belongs to the technical field of carbon nanotubes.

Background technique

In 2004, the AKGeim group of the University of Manchester in the United Kingdom made a breakthrough in the preparation of graphite samples with a single atomic layer thickness by mechanical exfoliation. They reported the phenomenon of field-effect electron transport in monolayer graphite ^[3] . Subsequently, in 2005, the Geim group and the P.Kim group of Columbia University in the United States successively reported that the integer quantum Hall effect was observed in single-layer graphite samples. In particular, the integer quantum Hall effect can be observed at room temperature, which is 10 times wider than the temperature range of other materials. Moreover, the electronic behavior of graphene is similar to that of relativistic particles. Due to the interaction of electrons with the periodic potential of the triangular lattice of graphene, the mass of Dirac Fermion in a single-layer graphite sample is almost zero and has a rather high mobility. The discovery enables phenomena that were previously only possible in expensive high-energy physics experiments to unfold in the laboratory. Graphene is a two-dimensional carbon nanostructure material composed of single-layer graphite sheets, which has excellent mechanical, electrical and thermal properties. The mobility of Graphene can exceed ~10 ⁴ cm ² /V·s, and the thermal conductivity (3500-5300W/mK). Therefore, carbon nanomaterials are considered to be one of the most promising materials for constructing future nanoelectronic circuits in a bottom-up manner. etc. are applied.

Group III nitride GaN crystals generally have a hexagonal wurtzite structure. It has a wide direct band gap of 3.39eV (room temperature), high thermal conductivity (1.3W/cm·K), strong atomic bonds, and good chemical stability. Good photoelectric properties have broad application prospects in solid-state lighting, high-temperature and high-power devices, and microwave devices. After the first-generation Ge, Si semiconductor materials, second-generation GaAs, InP compound semiconductor materials, together with SiC, diamond and other semiconductor materials, it is known as the third-generation semiconductor material. It is the frontier of semiconductor research and a hot spot for optoelectronic applications. . In 1928, GaN was synthesized for the first time, and in 1969, single crystal GaN crystal film was successfully prepared. After the 1990s, using buffer epitaxial layer technology, people have been able to grow GaN epitaxial layers on specific substrates; moreover, the difficulty of p-type doping of GaN semiconductors has also been broken through. GaN-based LEDs have also developed rapidly. In 1991, Nichia successfully developed GaN-based LEDs with a central wavelength of 430 nm. Currently, GaN-based LEDs have been commercialized. High-sensitivity ultraviolet light detectors have important applications in military, civil and scientific research. Compared with silicon photodiodes and photomultiplier tubes, the ultraviolet detector of group III nitride GaN crystal has lower dark current, wide super operating temperature, high breakdown field, and solar-blind ultraviolet detector without filtering . GaN ultraviolet detectors with p-i-n structure have advantages in providing lower dark current, higher detectivity, and higher responsivity.

Transparent conductive glass, as a key component of optoelectronic devices, is widely used in flat panel displays, microdisplays, photodetectors, and electrode materials for solar cells. The most commonly used conductive glass is indium tin oxide glass (ITO glass). ITO usually has a light transmittance greater than 80% in the visible light range, and a general electrical conductivity of (1-5)×10 ³ S/cm. However, the use of ITO is facing more and more serious problems. Since the In in ITO is expected to be exhausted on the earth within 10 years, the price of In has been as high as $1,000/kg in recent years, and the demand for ITO by electronics manufacturers has increased, making the price of ITO very expensive. In addition to becoming rarer and more expensive, ITO is prone to ion diffusion in the presence of acids and alkalis. Its use is harmful to the manufacturing plant environment and human health. At the same time, ions diffuse into the polymer insulating layer of the device, resulting in optical performance. drop, or even leakage leads to device damage. Therefore, finding and replacing materials with ITO properties and making devices with new materials has become an extremely urgent demand, which is of great significance to the development of a series of next-generation display and optoelectronic devices.

Recently discovered graphene films have been found to exhibit comparable properties to ITO in terms of electrical conductivity, light transmission, and flatness. And the Graphene film has the advantages of good chemical stability and low cost. Another advantage is that graphene has a high work function, and it is possible to form an ohmic contact with p-type GaN. Internationally, recently, some important progress has been made in the mass preparation of Graphene. Chemically reduced graphite oxide can be stably dispersed in aqueous solution through electrostatic interaction. Directly using the CVD method to synthesize single-layer and several-layer Graphene transparent conductive films has also been successful. These advances open up possibilities for applications in graphene LCDs, OLEDs, solar cells, and photodetectors.

Contents of the invention

The purpose of the present invention is to provide a graphene-based transparent conductive electrode and its preparation method and application, replace ITO or Ni/Au with graphene as the transparent conductive electrode of GaN-based LED, ultraviolet light detector, solve the problem due to In resources The restrictions on the development of photodetectors, solar cells, and touch screens are about to be exhausted, and the application of carbon nanomaterials will be broadened.

The first purpose of the present invention will be achieved through the following technical solutions:

The graphene-based transparent conductive electrode is characterized in that: the transparent conductive electrode is a graphene film, and the graphene film is solidified and bonded to the surface of the GaN substrate of the LED or the ultraviolet light detector. Wherein the graphene film is single-layer graphene, 2-50-layer composite graphene or a film composed of a mixture of the two, and the thickness of the graphene film is between 10 nm and 600 μm.

Yet another object of the present invention will be achieved through the following technical solutions:

The method for making a transparent conductive electrode based on graphene is characterized in that comprising steps:

1. The graphene film is prepared by chemical vapor deposition or reduced graphite oxide;

II. Migrate the graphene film to the surface of the GaN substrate of the LED or ultraviolet light detector by hot pressing in one of the methods of polymerization or vacuum filtration of the film, and anneal it;

III. Perform ultraviolet lithography, etching, and electron beam evaporation deposition on the graphene film and GaN substrate to form transparent conductive electrodes.

Further, the method for preparing a transparent conductive electrode based on graphene, wherein the graphene film is prepared by chemical vapor deposition in step I, its preparation conditions include: the carbon source used is methanol, ethanol, acetylene, methane or these gases Mixed gas; the metal thin film catalyst used is nickel, iron, copper, cobalt, ruthenium or platinum metal with a thickness of 50nm to 1000μm; and the chemical vapor deposition growth environment of graphene thin film is: 700°C to 1100°C under normal pressure or negative pressure , or UV light exposure to the environment.

Further, the method for preparing a transparent conductive electrode based on graphene, wherein the graphene film is prepared by reducing graphite oxide in step I, wherein the raw graphite powder used for redox includes natural graphite powder, flake graphite powder, Artificial graphite powder and expanded graphite powder; the method for reducing graphite oxide includes chemical reduction using hydrazine, NaBH ₄ , LiAlH ₄ , vitamin C, hydrogen as a reducing agent, or high-temperature heating reduction under the protection of an inert gas, or using chemical Reduction is carried out in a combined manner of reduction and high-temperature heating, and the prepared graphene film is dispersed graphene with hydroxyl or carboxyl groups.

Further, the aforementioned method for preparing transparent conductive electrodes based on graphene, wherein the polymer used for graphene film migration in step II adopts polydimethylsiloxane or polymethyl methacrylate, or the vacuum suction film adopts fiber Resin film or aluminum oxide film.

Another object of the present invention, its technical solution is:

GaN-based photoelectric devices, including LEDs and ultraviolet light detectors, are characterized in that: the graphene film is used as a transparent conductive electrode, which is cured and bonded to the surface of the detector substrate, and the form of the transparent conductive electrode includes a three-dimensional structure. The planar structure interdigitated electrodes, and the metal film electrodes connected to the transparent conductive electrodes of the graphene film and the outer metal leads are selected as Pd, Pd/Au, Sc, Au, Ti/Au, Ni/Au.

After the technical solution of the present invention is applied and implemented, its beneficial effects are reflected in:

Using graphene thin films instead of ITO or Ni/Au as transparent conductive electrodes for GaN-based LEDs and ultraviolet light detectors can realize low-cost, high-brightness light-emitting devices, and expand the application of carbon nanomaterials in the field of GaN-based optoelectronic devices.

Description of drawings

Figure 1 is a schematic diagram of a graphene film as a transparent conductive electrode of a GaN-based LED;

Fig. 2 is a schematic diagram of a transparent conductive electrode of a graphene film as a GaN-based ultraviolet light detector;

Figure 3a is a graphene thin film AFM synthesized by chemical vapor deposition method;

Figure 3b is a graphene film AFM synthesized by the reduced graphite oxide method;

Fig. 4 is the optical picture of graphene film;

Figure 5a is the optical transmittance of transparent conductive graphene film;

Figure 5b is an I-V curve diagram of the conductivity of the transparent conductive graphene film.

Detailed ways

In view of the increasingly scarce In resources, the present invention studies and proposes a graphene-based transparent conductive electrode for the purpose of seeking a low-cost, superior performance, and simpler alternative material for the transparent conductive electrode, and at the same time The preparation method and application of this kind of transparent conductive electrode are proposed.

The invention adopts the graphene transparent conductive film prepared by chemical vapor deposition or reduction and oxidation method, and utilizes the methods of micromachining photolithography, etching and metal deposition to manufacture GaN-based LED and ultraviolet light detector. Then transfer the graphene film to the p-type GaN substrate of the LED and the p-type GaN substrate of the ultraviolet light detector, instead of ITO or Ni/Au as a transparent conductive electrode. Based on GaN-based LEDs and ultraviolet light detectors made of graphene as a transparent conductive electrode, the luminous performance of the device is tested, which has a better effect and can realize low-cost, high-brightness light-emitting devices. GaN-based optoelectronic devices important in application. Wherein, the size of the graphite sheet is between 10 nm and 600 μm. Graphene film can be a film composed of single layer, thin layer (2-50 layers) or their mixture. The GaN-based LED can be designed to work in blue light, ultraviolet light or blue light plus phosphor powder white light LED.

A new method for graphene film to replace ITO or Ni/Au as a transparent conductive electrode for GaN-based LEDs and ultraviolet light detectors. The process steps to achieve its purpose are:

I. Graphene film can be prepared by chemical vapor deposition or reduction of graphite oxide; II. Graphene film migrates to GaN-based LED, ultraviolet light detector substrate surface, and annealing treatment; III. Graphene film and GaN-based Carry out ultraviolet lithography and etching on; IV, photoetching and depositing metal lead electrodes on the graphene film.

Wherein, the carbon source that chemical vapor deposition adopts in the step (1) is methanol, ethanol, acetylene, methane or mixed gas between them, and the metal film catalyst that the chemical vapor deposition of graphene adopts can be 50 nanometers-1000 micron thick Metal nickel, iron, copper, cobalt, ruthenium, platinum and other metals. Graphene CVD growth temperature is 700-1100 degrees Celsius. Graphene growth can be performed under normal atmospheric pressure or negative pressure. Graphene growth can also be performed under UV light irradiation.

In contrast, the reduced graphite oxide sheet in step (I) is dispersed graphene with hydroxyl or carboxyl groups prepared from graphite powder through chemical redox. The graphite powder used for chemical redox includes natural graphite powder, flake graphite powder, artificial graphite powder and expanded graphite powder. The method of reducing graphene can use reducing agents such as hydrazine, NaBH ₄ , LiAlH ₄ , vitamin C, etc., or can be reduced by heating at high temperature under the protection of hydrogen or inert gas. It can also be reduced by combining chemical reduction and high temperature heating.

In step (II), the migration of the graphene film: _the migration of the graphene film of chemical vapor deposition can adopt polymers such as PDMS, _PMMA ; Vacuum filtration method on membrane. The thin films prepared by the two methods can be transferred to GaN, and the contact can be improved by hot pressure transfer and annealing.

Further, the application form of the graphene thin film as a transparent conductive electrode of an optoelectronic device is diversified. On the one hand, it can be used as a transparent conductive electrode of a GaN-based ultraviolet photodetector in the form of upper and lower electrodes, and on the other hand, it can also be used as a transparent conductive electrode of a GaN-based ultraviolet photodetector in the form of a planar interdigitated electrode structure. No matter what form it takes, the metal thin film electrode connected to the graphene transparent conductive electrode and the outer metal lead can use Pd, Pd/Au, Sc, Au, Ti/Au, Ni/Au.

Below in conjunction with specific embodiment and accompanying drawing, the present invention will be further described:

Example 1:

Referring to Fig. 1 for the description of the drawings, graphene films are used to make transparent conductive electrodes of GaN-based LEDs.

(1) Use electron beam evaporation, magnetron sputtering or thermal evaporation of 100nm-500nm metal Ni film on the Si/ _SiO2 substrate, put it into a tube furnace as a catalyst for chemical vapor deposition, and heat up under hydrogen and argon 850°C-1000°C, after reducing with hydrogen for 20 minutes, feed methane, the reaction time is 3-5 minutes, stop methane, lower the temperature under the protection of hydrogen, and take out the sample.

(2) Place the grown GaN epitaxial wafer containing quantum wells in a tube furnace, and keep it at 750° C. for 15 minutes under N ₂ environment to activate the Mg-doped P-type GaN layer.

(3) Place in BOE (H ₂ SO ₄ : _{H 2} O ₂ =3:1) solution to wash at 70°C for 3 minutes, and keep at 120°C on a hot plate for 5 minutes to remove residual solution.

(4) Take the graphene sample grown on the Si/SiO ₂ substrate, spin-coat PMMA with a thickness of 100nm-300nm on it, and bake for 2h. Then put in 1mol/L NaOH aqueous solution, heat at 80°C until the nickel film falls off from the silicon wafer, take out the fallen nickel film-graphene-PMMA, put in 1mol/L FeCl ₃ aqueous solution, dissolve the nickel film and take it out , put it on the GaN epitaxial wafer in the aqueous solution, blow dry with _N2 gas, and heat at 80°C for a few minutes to make the graphene and the epitaxial wafer firmly bond.

(5) Deposit SiO ₂ with a thickness of 450 nm in plasma enhanced chemical vapor deposition (PECVD) and use it as an etching mask for inductively coupled plasma (ICP).

(6) The first photolithography: the purpose is to etch to n-GaN, and determine the area of p-GaN ~ 200μm ² -1000μm ² . Spin-coat photoresist (AZ5214 positive resist), process parameters: low speed 600rpm/8s, high speed 4000rpm/30s, front-baking on hot plate 95°C/90s, vacuum exposure mode, exposure time 7.5s, place developer For 40 s, remove the developer in deionized water, and blow dry with N ₂ gas.

(7) Hard film: place on a hot plate at 110° C. for 60 seconds to make the photoresist and the wafer firmly adhere.

(8) Wet etching of SiO ₂ : place the sample in a buffered etching solution (40% NH ₄ F:49% HF=6:1) for 180 s. After the corrosion was completed, the corrosion situation was observed under a metallographic microscope.

(9) Place in H ₂ SO4 : _{H 2} O ₂ (3:1) solution at 50° C. for 3 minutes to remove the photoresist. Keep at 120°C on a hot plate for 3 minutes to remove residual solution. Use a step meter to measure the corrosion depth of the _SiO2 layer to check the corrosion situation.

(10) Oxygen plasma etching of graphene film. Then ICP dry etching of GaN, Cl ₂ (80sccm)/CH ₄ (3sccm)/He (10sccm), etch for 200s, ultrasonic cleaning in KOH solution at 90°C for 5min to remove the pollution caused by etching. Place in BOE (H ₂ SO ₄ : _{H 2} O ₂ =3:1) solution for 5 min to remove SiO ₂ .

(11) Measure whether the etching depth reaches n-GaN, and observe the etching situation under a metallographic microscope.

(12) Second photolithography: the purpose is to deposit n-GaN ohmic contact electrode Ti/Al. Process parameters of photoresist AZ5214: low speed 600rpm/8s, high speed 4000rpm/30s, front baking on hot plate 95°C/90s, vacuum exposure mode, exposure time 7.5s, placed in developer for 40s, deionized water Remove the developing solution and blow dry with _N2 .

(13) Hard film: place on a hot plate at 110° C. for 60 seconds to firmly bond the photoresist and the wafer.

(14) Electron beam evaporation deposits 200nm Ti/Al electrodes. Put it in a plasma degumming machine at 60°C for 5 minutes, wash it with deionized water, and observe it with a metallographic microscope.

(15) Third photolithography: the purpose is to deposit ohmic contact electrodes to the graphene connected to p-GaN. Spin coating HMDS, the process parameters are: low speed 600rpm/10s, high speed 6000rpm/15s. Place on a hot plate at 90°C for 90s. Spin-coat photoresist (AZ5214 positive resist), process parameters: low speed 600rpm/8s, high speed 4000rpm/30s, front-baking on hot plate 95°C/90s, vacuum exposure mode, exposure time 7.5s, place developer For 40s, remove the developer in deionized water, and blow dry with N ₂ .

(16) Hard film: place on a hot plate at 110° C. for 60 seconds to firmly bond the photoresist and the wafer.

(17) Electron beam evaporation deposits Pd/Au (~300nm), with an area of about 40μm ² .

(18) Metal stripping, photoresist is removed in a plasma stripper.

(19) The semiconductor parameter meter combines the light intensity meter and the brightness meter to characterize the LED performance.

Example 2:

Referring to Figure 2, the graphene film is used to make transparent conductive electrodes of GaN-based ultraviolet light detectors.

(1) Use electron beam evaporation, magnetron sputtering or thermal evaporation of 100nm-500nm metal Ni film on the Si/ _SiO2 substrate, put it into a tube furnace as a catalyst for chemical vapor deposition, and heat up under hydrogen and argon 850°C-1000°C, after reducing with hydrogen for 20 minutes, feed methane, the reaction time is 3-5 minutes, stop methane, lower the temperature under the protection of hydrogen, and take out the sample.

(2) Place the pin GaN epitaxial wafer in a tube furnace, keep it at 750° C. for 15 minutes under N ₂ environment, and activate the P-type GaN layer doped with Mg.

(3) Place in BOE (H ₂ SO ₄ : _{H 2} O ₂ =3:1) solution to wash at 70°C for 3 minutes, and keep at 120°C on a hot plate for 5 minutes to remove residual solution.

(4) Take a graphene sample grown on a Si/SiO ₂ substrate, spin-coat PMMA with a thickness of 100nm-300nm on it, and bake for 2h. Then put in 1mol/L NaOH aqueous solution, heat at 80°C until the nickel film falls off from the silicon wafer, take out the fallen nickel film-graphene-PMMA, put in 1mol/L FeCl ₃ aqueous solution, dissolve the nickel film and take it out , put it on the GaN epitaxial wafer in the aqueous solution, blow dry with _N2 gas, and heat at 80°C for a few minutes to make the graphene and the epitaxial wafer firmly bond.

(5) 450nm SiO ₂ is deposited by plasma enhanced chemical vapor deposition (PECVD) and used as an etching mask for inductively coupled plasma (ICP).

(6) The first photolithography: the purpose is to etch to n-GaN, and the area of p-GaN is determined to be about 200 μm ² -1000 μm ² . Spin-coat photoresist (AZ5214 positive resist), process parameters: low speed 600rpm/8s, high speed 4000rpm/30s, front-baking on hot plate 95°C/90s, vacuum exposure mode, exposure time 7.5s, place developer For 40 s, remove the developer in deionized water, and blow dry with N ₂ gas.

(7) Hard film: Place on a hot plate at 110°C for 60s to make the photoresist and wafer firmly bond

(8) Place the sample in buffered corrosion solution (40% NH ₄ F:49% HF=6:1) for 180s. After the corrosion was completed, the corrosion situation was observed under a metallographic microscope.

(9) Place in BOE (H ₂ SO ₄ : _{H 2} O ₂ =3:1) solution at 50° C. for 3 minutes to remove the photoresist. Keep at 120°C on a hot plate for 3 minutes to remove residual solution. Use a step meter to measure the corrosion depth of the _SiO2 layer to check the corrosion situation.

(10) Oxygen plasma etching of graphene film. Then ICP dry etching of GaN, Cl ₂ (80sccm)/CH ₄ (3sccm)/He (10sccm), etch for 200s, ultrasonic cleaning in KOH solution at 90°C for 5min to remove the pollution caused by etching. Place in BOE (H ₂ SO ₄ : _{H 2} O ₂ =3:1) solution for 5 min to remove SiO ₂ .

(11) Measure whether the etching depth reaches n-GaN, and observe the etching situation under a metallographic microscope.

(12) Second photolithography: the purpose is to deposit n-GaN ohmic contact electrode Ti/Al. Process parameters of photoresist AZ5214: low speed 600rpm/8s, high speed 4000rpm/30s, front baking on hot plate 95°C/90s, vacuum exposure mode, exposure time 7.5s, placed in developer for 40s, deionized water Remove the developing solution and blow dry with _N2 .

(13) Hard film: place on a hot plate at 110° C. for 60 seconds to firmly bond the photoresist and the wafer.

(14) Electron beam evaporation deposits 200nm Ti/Al electrodes. Put it in a plasma degumming machine at 60°C for 5 minutes, wash it with deionized water, and observe it with a metallographic microscope.

(15) Third photolithography: the purpose is to deposit ohmic contact electrodes to the graphene connected to p-GaN. Spin-coat HMDS, process parameters: low speed 600rpm/10s, high speed 6000rpm/15s. Place on hot plate at 90°C for 90s. Spin-coat photoresist (AZ5214 positive resist), process parameters: low speed 600rpm/8s, high speed 4000rpm/30s, front-bake on a hot plate at 95°C/90s, use vacuum exposure mode, exposure time is 7.5s, place in developer for 40s, remove developer in deionized water, blow dry with _N2 .

(16) Hard film: place on a hot plate at 110° C. for 60 seconds to firmly bond the photoresist and the wafer.

(17) Electron beam evaporation deposits Pd/Au (~300nm), with an area of about 40μm ² .

(18) Metal stripping, photoresist is removed in a plasma stripper.

(19) Semiconductor parameter instrument combined with ultraviolet light source to characterize the performance of ultraviolet light detector.

As shown in Figure 3a and Figure 3b, it is the atomic force microscope picture of graphene grown by chemical vapor deposition. The atomic force microscope picture can be used to judge that the synthesized graphene is a thin layer (1-20 layers), and the surface of the graphene film has wrinkled morphology .

Optical pictures of graphene films and graphene samples after migration as shown in Figure 4.

As shown in Figure 5a, it can be seen that the light transmittance of the obtained graphene film in the range of wavelength 400nm～1100nm is about 75%, and as shown in Figure 5b, utilize the four-point method to measure the current-voltage (IV) curve of the graphene film , the sheet resistance obtained by calculation is R _sh ≈1kΩ/sq.

Claims (10)

1. based on the transparency conductive electrode of Graphene, it is characterized in that: described transparency conductive electrode is a graphene film, and this graphene film solidifies the GaN substrate surface that is incorporated into LED or ultraviolet light detector.

2. the transparency conductive electrode based on Graphene according to claim 1, it is characterized in that: described graphene film is single-layer graphene, 2 layers～50 layers composite graphite alkene or the film that both mix composition, and the gauge of this graphene film is between 10nm～600 μ m.

3. the method for making of the described transparency conductive electrode based on Graphene of claim 1 is characterized in that comprising step:

The mode of I, employing chemical vapour deposition technique or reduction-oxidation graphite prepares graphene film;

II, adopt a kind of method hot pressing in polymerization or the film vacuum filtration to move to the GaN substrate surface of LED or ultraviolet light detector graphene film, and annealing in process;

III, graphene film and GaN substrate are carried out ultraviolet photolithographic, etching, and electron-beam evaporation forms transparency conductive electrode.

4. the method for making of the transparency conductive electrode based on Graphene according to claim 3, it is characterized in that: adopt the process for preparing graphenes by chemical vapour deposition film among the step I, its preparation condition comprises: the carbon source that adopts is the mist of methyl alcohol, ethanol, acetylene, methane or these gases; The metallic film catalyst that adopts is nickel, iron, copper, cobalt, ruthenium or the platinum that 50nm～1000 μ m are thick; And the chemical vapor deposition growth environment of graphene film is: following 700 ℃～1100 ℃ of normal pressure or negative pressure.

5. the method for making of the transparency conductive electrode based on Graphene according to claim 4 is characterized in that: adopt the process for preparing graphenes by chemical vapour deposition film among the step I, described Graphene grows under the environment of UV-irradiation.

6. the method for making of the transparency conductive electrode based on Graphene according to claim 3, it is characterized in that: adopt the mode of reduction-oxidation graphite to prepare graphene film among the step I, wherein saidly be used for redox raw material graphite powder and comprise natural graphite powder, crystalline graphite powder, graphous graphite powder and expanded graphite powder; The method of described reduction-oxidation graphite comprises employing hydrazine, NaBH ₄, LiAlH ₄, vitamin C, hydrogen carry out electronation as reducing agent or carry out the heat reduction under inert gas shielding; or the mode that adopts electronation and heat to combine reduces, and the described graphene film that makes is the dispersion Graphene with hydroxyl or carboxyl.

7. the method for making of the transparency conductive electrode based on Graphene according to claim 3 is characterized in that: the polymer of graphene film migration usefulness adopts dimethyl silicone polymer or polymethyl methacrylate in the Step II.

8. the method for making of the transparency conductive electrode based on Graphene according to claim 3 is characterized in that: the vacuum filtration film of graphene film migration usefulness adopts fibre resin film or alundum (Al film in the Step II.

9.GaN base photoelectric device, comprise LED and ultraviolet light detector, it is characterized in that: as transparency conductive electrode, solidify the substrate surface that is incorporated into detector with graphene film, the form of described transparency conductive electrode comprises that stereochemical structure refers to electrode or the interdigital electrode of planar structure up and down.

10. GaN base photoelectric device according to claim 9 is characterized in that: the metal film electrode that the transparency conductive electrode of described graphene film links to each other with outer metal lead wire is elected Pd, Pd/Au, Sc, Au, Ti/Au, Ni/Au as.

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