CN110504229A - A kind of high thermal conductivity material and its preparation method and application - Google Patents

Abstract

The invention provides a method for preparing a high thermal conductivity material, comprising providing a substrate, depositing a gallium-containing compound layer on the substrate; depositing a diamond-like carbon layer on the gallium-containing compound layer by using physical vapor deposition; depositing a diamond-like carbon layer on the gallium-containing compound layer by using chemical vapor deposition The first diamond layer is deposited on the layer, and during the chemical vapor deposition process, the diamond-like layer is transformed into a second diamond layer; the substrate is removed to obtain a high thermal conductivity material, which is added between the gallium-containing compound layer and the first diamond layer. The diamond-like layer is used to protect the gallium-containing compound layer from being cracked when the first diamond layer is deposited at high temperature, and at the same time the diamond-like layer is transformed into a diamond layer. The gallium-containing compound layer is in direct contact with the diamond layer and has a high bonding force, and the diamond layer nucleates The density is high, the crystallization quality is good, and the thermal conductivity efficiency of the final high thermal conductivity material is high, the heat dissipation performance is good, and it has a wide application prospect in semiconductor devices.

Description

A kind of high thermal conductivity material and its preparation method and application

technical field

The invention relates to the field of semiconductors, in particular to a high thermal conductivity material and its preparation method and application.

Background technique

Gallium-containing compound-based semiconductor materials such as gallium nitride and gallium phosphide have the characteristics of large band gap, direct gap, and fast electron drift, and have advantages in the production of high-power, high-frequency electronic devices and optoelectronic devices. For example, gallium nitride is mainly epitaxially grown on substrates such as silicon and sapphire, but the thermal conductivity of these substrates is low, which seriously restricts the heat dissipation of gallium nitride devices and limits the performance of devices.

Diamond is the highest thermal conductivity material, with a thermal conductivity of up to 2000W/(m·k), and its chemical properties are stable, and it has a large band gap, making it an ideal substrate material choice. However, the ideal growth temperature of diamond is 800°C-1000°C. In this temperature range, the gallium-containing compound reacts with the active hydrogen plasma, resulting in the decomposition of the gallium-containing compound film, and the bond between the deposited diamond film interface and the gallium-containing compound layer If the force is poor, the diamond film is prone to peeling and cracking; if the diamond growth temperature is lowered, although the decomposition of gallium-containing compounds can be reduced to a certain extent, the decomposition of gallium-containing compounds is inevitable in the hydrogen plasma environment, and in Under low temperature conditions, the growth rate of diamond is slow, and the quality of deposited diamond is poor.

Therefore, how to overcome the cracking of the gallium-containing compound layer and the peeling off of the diamond film, improve the crystal quality of diamond and the bonding force with the surface of the gallium-containing compound, so as to improve the thermal conductivity is an urgent problem to be solved.

Contents of the invention

In view of this, the present invention provides a method for preparing a high thermal conductivity material, comprising preparing a gallium-containing compound layer, a diamond-like layer and a first diamond layer on a substrate, and when depositing the first diamond layer, the diamond-like layer protects the The gallium compound layer is not cracked under high temperature conditions, and the diamond-like carbon layer is transformed into a second diamond layer at the same time, and the substrate can be finally removed. The prepared high thermal conductivity material includes a gallium-containing compound layer and a diamond layer disposed on the gallium-containing compound layer. The diamond layer includes a first diamond layer and a second diamond layer. The gallium-containing compound layer is in direct contact with the diamond layer. At the same time, the diamond layer The nucleation density is high, the crystallization quality is good, and the bonding force with the gallium-containing compound layer is high, and a material with high thermal conductivity is obtained.

In a first aspect, the present invention provides a method for preparing a high thermal conductivity material, comprising:

providing a substrate on which to deposit a gallium-containing compound layer;

depositing a diamond-like carbon layer on the gallium-containing compound layer by physical vapor deposition;

depositing a first diamond layer on the diamond-like layer by chemical vapor deposition during which the diamond-like layer is transformed into a second diamond layer;

Removing the substrate yields a highly thermally conductive material.

Optionally, the material of the substrate includes at least one of silicon, silicon carbide, aluminum nitride, zinc oxide, gallium arsenide and sapphire (Al ₂ O ₃ ).

Optionally, the material of the gallium-containing compound layer includes at least one of gallium nitride, gallium phosphide, gallium arsenide, aluminum gallium arsenide, aluminum gallium phosphide, indium gallium nitride, and aluminum indium gallium phosphide . Further optionally, the material of the gallium-containing compound layer includes at least one of gallium nitride, gallium phosphide, aluminum gallium phosphide, and aluminum indium gallium phosphide. Further optionally, the material of the gallium compound layer includes gallium nitride.

Optionally, the depositing a gallium-containing compound layer on the substrate includes:

The gallium-containing compound layer is deposited on the substrate by metal organic chemical vapor deposition, molecular beam epitaxy, liquid phase growth or evaporation.

Further optionally, a gallium-containing compound layer is deposited on the substrate by metal organic chemical vapor deposition.

Optionally, the thickness of the gallium-containing compound layer is 0.2 μm-1.4 μm. Further optionally, the thickness of the gallium-containing compound layer is 0.3 μm-1.0 μm.

Optionally, the physical vapor deposition includes at least one of vacuum evaporation, ion coating, magnetron sputtering, and molecular beam epitaxy. Further optionally, magnetron sputtering is used to deposit a diamond-like carbon layer on the gallium-containing compound layer. Specifically, the conditions of the magnetron sputtering: the flow of hydrogen is 10sccm-20sccm, the flow of argon is 20sccm-40sccm, the volume ratio of hydrogen to argon is (1-1.5):(2-3), and the chamber pressure is 1mtorr-8mtorr, working voltage 400V-700V, magnetron sputtering power 4kW-9kW, sputtering time 5min-15min.

Optionally, the thickness of the diamond-like carbon layer is 200nm-500nm. Further optionally, the thickness of the diamond-like carbon layer is 230nm-450nm. Specifically, the thickness of the diamond-like carbon layer may be, but not limited to, 250nm-435nm, 275nm-420nm or 290nm-400nm.

Optionally, the depositing the first diamond layer on the diamond-like layer by chemical vapor deposition includes:

Pretreating the substrate deposited with the gallium-containing compound layer and the diamond-like carbon layer, placing it in a suspension of diamond powder, performing a crystal planting operation, and then using chemical vapor deposition on the diamond-like carbon A first diamond layer is prepared on the layer.

Optionally, the pretreatment includes cleaning and drying the substrate. Specifically, the cleaning and drying treatment may be, but not limited to, ultrasonically cleaning the substrate in deionized water, then ultrasonically cleaning in acetone, and then statically drying.

Optionally, the particle size of the diamond powder is 3nm-10nm. Further optionally, the particle size of the diamond powder is 4nm-9nm. Specifically, the particle size of the diamond powder may be 5nm, 5.8nm, 6.3nm, 7.5nm or 8nm, etc. The diamond powder can be nano-diamond powder, detonation nano-diamond powder, etc., which can be selected according to actual needs, and is not limited here.

Optionally, the mass concentration of the diamond powder in the diamond powder suspension is 0.003%-0.01%. Further optionally, the mass concentration of the diamond powder in the diamond powder suspension is 0.005%-0.01%.

Optionally, the crystal planting operation includes ultrasonic treatment at a power of 2kW-8kW for 15min-45min. Further optionally, the crystal planting operation includes ultrasonic treatment at a power of 3kW-7kW for 20min-45min. Further optionally, the crystal planting operation includes ultrasonic treatment for 30 min at a power of 4 kW. Specifically, placing the substrate in the suspension of diamond powder for ultrasonic treatment is a crystal planting operation.

Optionally, the deposition rate of the chemical vapor deposition is 300nm/h-500nm/h.

Optionally, the chemical vapor deposition includes at least one of atmospheric pressure chemical vapor deposition, low pressure chemical vapor deposition, ultra-high vacuum chemical vapor deposition and hot wire chemical vapor deposition. Specifically, it can be, but not limited to, hot wire chemical vapor deposition.

Optionally, the process parameters of the chemical vapor deposition include: evacuate the chamber to below 0.1Pa, use tantalum wire as the heating wire, the number of heating wires is 7-13, and the diameter of the heating wire is 0.3mm-1mm , the flow rate of hydrogen is 800sccm-1000sccm, the flow rate of methane is 12sccm-32sccm, the deposition temperature is 750°C-950°C, the deposition power is 6500W-7500W, and the air pressure is 3500Pa-4500Pa.

In the present invention, the material of the diamond-like carbon layer is diamond-like carbon, which contains an amorphous metastable structure with sp3 and sp2 bonded carbon mixed. During the chemical vapor deposition process, due to the high deposition temperature, the hydrogen in it is converted into hydrogen free radicals , react with sp2 hybridized carbon atoms to form sp3 hybridized carbon atoms. Therefore, while the diamond layer is deposited by chemical vapor phase, the sp2 hybridization of carbon atoms in the diamond-like layer is transformed into sp3 hybridization, thereby becoming diamond, and the diamond-like layer is transformed into the second diamond layer. After the final deposition, the gallium-containing compound layer is covered with a diamond layer without the diamond-like carbon layer, and the gallium-containing compound layer is in direct contact with the second diamond layer. The diamond layer includes a first diamond layer and a second diamond layer.

Optionally, the removing the substrate includes:

The substrate is removed by laser lift-off technology, chemical lift-off technology or epitaxial layer lift-off technology.

Further optionally, the substrate is removed using a laser lift-off technique.

In the present invention, the binding force between the gallium-containing compound layer and the diamond layer measured by Rockwell indentation method is 400N-1000N. The nucleation density of diamonds in the diamond layer measured by scanning electron microscopy is (5-10)×10 ¹⁰ pieces/cm ² .

A method for preparing a high thermal conductivity material provided by the first aspect of the present invention comprises preparing a gallium-containing compound layer, a diamond-like carbon layer and a first diamond layer on a substrate, and finally removing the substrate; Adding a diamond-like layer between the layers can protect the gallium-containing compound layer when depositing the first diamond layer at high temperature, isolate the active hydrogen plasma from reacting with the gallium-containing compound layer, and avoid the cracking of the gallium-containing compound layer; when preparing the diamond layer, The sp2 hybridized carbon atoms in the diamond-like layer transform into sp3 hybridized carbon atoms, and finally become diamonds, which can be used as a carbon source for the growth of the diamond layer, increase the nucleation density, and obtain a continuous and dense first diamond layer. At the same time, the like The diamond layer is transformed into a second diamond layer; in the final high thermal conductivity material, the gallium-containing compound layer is in direct contact with the diamond layer, the diamond crystal quality is good, and the bonding force with the gallium-containing compound layer is high, thereby obtaining high thermal conductivity. Material.

In a second aspect, the present invention provides a high thermal conductivity material prepared by the preparation method described in the first aspect, the high thermal conductivity material comprising a gallium-containing compound layer and a diamond layer disposed on the gallium-containing compound layer, The diamond layer includes the first diamond layer and the second diamond layer.

Optionally, the binding force between the gallium-containing compound layer and the diamond layer is 400N-1000N, and the nucleation density of diamonds in the diamond layer is (5-10)×10 ¹⁰ pieces/cm ² .

The invention provides a high thermal conductivity material, wherein the gallium-containing compound layer does not have cracking, and the diamond nucleation density in the diamond layer; the gallium-containing compound layer is in direct contact with the diamond layer, and the bonding force is high; at the same time, due to the existence of the diamond layer , High thermal conductivity material with high heat dissipation efficiency.

In a third aspect, the present invention provides a semiconductor device, including the high thermal conductivity material prepared by the preparation method described in the first aspect or the high thermal conductivity material described in the second aspect, and the high thermal conductivity material is used as the semiconductor device epitaxial layer.

Wherein, the semiconductor device includes at least one of a crystal diode, a bipolar transistor and a field effect transistor. Specifically, when the semiconductor device is a light emitting diode, the high thermal conductivity material may be used as an epitaxial layer of the light emitting diode.

Beneficial effects of the present invention:

(1) The present invention provides a kind of preparation method of high thermal conductivity material, comprise preparing gallium-containing compound layer, diamond-like carbon layer and the first diamond layer on the substrate, remove substrate at last; Adding a diamond-like layer between the layers can protect the gallium-containing compound layer when depositing the first diamond layer at high temperature, isolate the active hydrogen plasma from reacting with the gallium-containing compound layer, and avoid the cracking of the gallium-containing compound layer; when preparing the diamond layer, The sp2 hybridized carbon atoms in the diamond-like layer are transformed into sp3 hybridized carbon atoms, and finally become diamond, which can be used as a carbon source for the growth of the diamond layer to increase the nucleation density and obtain a continuous and dense first diamond layer. At the same time, the like The diamond layer is transformed into a second diamond layer, and the gallium-containing compound layer is in direct contact with the diamond layer;

(2) The present invention provides a kind of high thermal conductivity material, there is no cracking situation in the gallium-containing compound layer, and the diamond nucleation density in the diamond layer; the gallium-containing compound layer is in direct contact with the diamond layer, the bonding force is high, and the high thermal conductivity material is improved. The thermal conduction efficiency has a good application prospect in semiconductor devices, especially in semiconductor epitaxial layers.

Description of drawings

Fig. 1 is a flow chart of a method for preparing a high thermal conductivity material provided by an embodiment of the present invention;

2 is a schematic diagram of step S101 in a method for preparing a high thermal conductivity material provided by an embodiment of the present invention;

3 is a schematic diagram of step S102 in a method for preparing a high thermal conductivity material provided by an embodiment of the present invention;

4 is a schematic diagram of step S103 in a method for preparing a high thermal conductivity material provided by an embodiment of the present invention;

FIG. 5 is a schematic diagram of step S104 in a method for preparing a high thermal conductivity material provided by an embodiment of the present invention.

Detailed ways

The following descriptions are preferred implementations of the embodiments of the present invention. It should be pointed out that those skilled in the art can make some improvements and modifications without departing from the principles of the embodiments of the present invention. These improvements And retouching are also regarded as the scope of protection of the embodiments of the present invention.

Please refer to Fig. 1, the preparation method of a kind of high thermal conductivity material provided by the present invention, comprises:

Step S101: providing a substrate, and depositing a gallium-containing compound layer on the substrate.

In step S101 , referring to FIG. 2 , a substrate 10 is provided, and a gallium-containing compound layer 11 is deposited on the substrate 10 . Wherein, the material of the substrate 10 includes at least one of silicon, silicon carbide, aluminum nitride, zinc oxide, gallium arsenide and sapphire (Al ₂ O ₃ ). The material of the gallium-containing compound layer 11 includes at least one of gallium nitride, gallium phosphide, gallium arsenide, aluminum gallium arsenide, aluminum gallium phosphide, indium gallium nitride and aluminum indium gallium phosphide. Further optionally, the material of the gallium-containing compound layer 11 includes at least one of gallium nitride, gallium phosphide, aluminum gallium phosphide, and aluminum indium gallium phosphide. Further optionally, the material of the gallium compound layer 11 includes gallium nitride. In an embodiment of the present invention, depositing the gallium-containing compound layer 11 on the substrate 10 includes: depositing the gallium-containing compound layer 11 on the substrate 10 by metal organic chemical vapor deposition, molecular beam epitaxy, liquid phase growth or evaporation. Further optionally, the gallium-containing compound layer 11 is deposited on the substrate 10 by metal organic chemical vapor deposition. Optionally, the thickness of the gallium-containing compound layer 11 is 0.2 μm-1.4 μm. Further optionally, the thickness of the gallium-containing compound layer 11 is 0.3 μm-1.0 μm. The thickness of the substrate 10 is not limited, and can be selected according to actual needs.

Step S102: depositing a diamond-like carbon layer on the gallium-containing compound layer by physical vapor deposition.

In step S102 , referring to FIG. 3 , a diamond-like carbon layer 12 is deposited on the gallium-containing compound layer 11 by physical vapor deposition. Optionally, physical vapor deposition includes at least one of vacuum evaporation, ion coating, magnetron sputtering, and molecular beam epitaxy. Further optionally, the diamond-like carbon layer 12 is deposited on the gallium-containing compound layer 11 by magnetron sputtering. Specifically, the conditions of magnetron sputtering: the flow rate of hydrogen is 10sccm-20sccm, the flow rate of argon is 20sccm-40sccm, the volume ratio of hydrogen to argon is (1-1.5):(2-3), and the chamber pressure is 1mtorr- 8mtorr, the working voltage is 400V-700V, the magnetron sputtering power is 4kW-9kW, and the sputtering time is 5min-15min. The thickness of the diamond-like carbon layer 12 is 200nm-500nm. Further optionally, the thickness of the diamond-like carbon layer 12 is 230nm-450nm. Specifically, the thickness of the diamond-like carbon layer 12 may be, but not limited to, 250nm-435nm, 275nm-420nm or 290nm-400nm. The deposition temperature in physical vapor deposition is lower than the temperature of chemical vapor deposition, no active hydrogen plasma will be generated, no cracking of the gallium-containing compound 11 will be caused, and the binding force between the diamond-like layer 12 and the gallium-containing compound 11 is large, It will not cause the diamond-like carbon layer 12 to fall off.

Step S103: Depositing a first diamond layer on the diamond-like layer by chemical vapor deposition, and during the chemical vapor deposition process, the diamond-like layer is transformed into a second diamond layer.

In step S103, referring to FIG. 4 , the first diamond layer 13 is deposited on the diamond-like layer 12 by chemical vapor deposition. During the chemical vapor deposition process, the sp2 hybridized carbon in the diamond-like layer 12 The atoms become sp3 hybridized carbon atoms, and the diamond-like carbon layer 12 becomes the second diamond layer 14 . In an embodiment of the present invention, depositing the first diamond layer 13 on the diamond-like carbon layer 12 by chemical vapor deposition includes: pre-treating the substrate 10 deposited with the gallium-containing compound layer 11 and the diamond-like carbon layer 12, and placing the The crystal planting operation is carried out in the suspension of diamond powder, and then the first diamond layer 13 is prepared on the diamond-like layer 12 by chemical vapor deposition. In an embodiment of the present invention, the pretreatment includes washing and drying. Specifically, the cleaning and drying treatment may be, but not limited to, ultrasonically cleaning the substrate 10 deposited with the gallium-containing compound layer 11 and the diamond-like carbon layer 12 in deionized water, then ultrasonically cleaning in acetone, and then statically drying. In an embodiment of the present invention, the particle size of the diamond powder is 3nm-10nm. Further optionally, the particle size of the diamond powder is 4nm-9nm. Specifically, the particle size of the diamond powder may be 5nm, 5.8nm, 6.3nm, 7.5nm or 8nm, etc. The diamond powder can be nano-diamond powder, detonation nano-diamond powder, etc., which can be selected according to actual needs, and is not limited here. In the embodiment of the present invention, the mass concentration of the diamond powder in the diamond powder suspension is 0.003%-0.01%. Further optionally, the mass concentration of the diamond powder in the diamond powder suspension is 0.005%-0.01%. In the embodiment of the present invention, the crystal planting operation includes ultrasonic treatment at a power of 2kW-8kW for 15min-45min. Further optionally, the crystal planting operation includes ultrasonic treatment at a power of 3kW-7kW for 20min-45min. Further optionally, the crystal planting operation includes ultrasonic treatment for 30 min at a power of 4 kW. Specifically, placing the substrate 10 deposited with the gallium-containing compound layer 11 and the diamond-like carbon layer 12 in a suspension of diamond powder for ultrasonic treatment is a crystal planting operation. In an embodiment of the present invention, chemical vapor deposition includes at least one of atmospheric pressure chemical vapor deposition, low pressure chemical vapor deposition, ultra-high vacuum chemical vapor deposition and hot wire chemical vapor deposition. Specifically, it can be, but not limited to, hot wire chemical vapor deposition. In the embodiment of the present invention, the process parameters of chemical vapor deposition include: evacuate the chamber to below 0.1Pa, use tantalum wire as the hot wire, the number of hot wire is 7-13, and the diameter of the hot wire is 0.3mm- 1mm, the flow rate of hydrogen gas is 800sccm-1000sccm, the flow rate of methane is 12sccm-32sccm, the deposition temperature is 750°C-950°C, the deposition power is 6500W-7500W, and the air pressure is 3500Pa-4500Pa. In an embodiment of the present invention, the deposition rate of chemical vapor deposition is 300 nm/h-500 nm/h. The thickness of the first diamond layer 13 is not limited, and is selected according to actual needs. After finally depositing the first diamond layer 13, on the gallium-containing compound layer 11 is a diamond layer 15 without a diamond-like layer 12, the gallium-containing compound layer 11 is in direct contact with the second diamond layer 14, and the diamond layer 15 comprises the first diamond layer 13 and the second diamond layer 14.

Step S104: removing the substrate to obtain a high thermal conductivity material.

In step S104 , referring to FIG. 5 , the substrate 10 is removed to obtain a high thermal conductivity material. Optionally, removing the substrate 10 includes removing the substrate 10 using laser lift-off technology, chemical lift-off technology or epitaxial layer lift-off technology. Further optionally, the substrate 10 is removed using a laser lift-off technique. The resulting highly thermally conductive material includes a gallium-containing compound layer 11 and a diamond layer 15 disposed on the gallium-containing compound layer 11 , and the diamond layer 15 includes the first diamond layer 13 and the second diamond layer 14 . In the embodiment of the present invention, the binding force between the gallium-containing compound layer 11 and the diamond layer 15 is determined to be 400N-1000N by Rockwell indentation method. The nucleation density of diamonds in the diamond layer 15 was determined by scanning electron microscope to be (5-10)×10 ¹⁰ diamonds/cm ² .

The present invention also provides a semiconductor device, comprising the high thermal conductivity material prepared above, and the high thermal conductivity material is used as an epitaxial layer of the semiconductor device. Wherein, the semiconductor device includes at least one of a crystal diode, a bipolar transistor and a field effect transistor. Specifically, when the semiconductor device is a light emitting diode, the high thermal conductivity material may be used as an epitaxial layer of the light emitting diode. When the high thermal conductivity material is used as the epitaxial layer of the light-emitting diode, the heat conduction efficiency of the high thermal conductivity material is improved, and the heat dissipation performance is good, thereby increasing the heat dissipation effect of the light-emitting diode, improving the working efficiency of the light-emitting diode, and prolonging the service life.

The present invention will be further described with multiple specific embodiments below.

Example 1

A method for preparing a high thermal conductivity material, comprising the steps of:

(1) Provide sapphire (Al ₂ O ₃ ) as a substrate, clean the sapphire with acetone, etch it in a mixture of dilute sulfuric acid and phosphoric acid, and finally place it in an ultra-high vacuum chamber to remove the surface of the substrate Volatile substances were removed, and a gallium nitride layer was prepared on sapphire by metal-organic chemical vapor deposition.

(2) The sapphire deposited with the gallium nitride layer was ultrasonically cleaned with ethanol and deionized water for 5 minutes to remove the oil and dust on the surface, and dried with nitrogen; the dried substrate was placed in the sputtering chamber for magnetron sputtering. The sputtering environment is a mixed gas of hydrogen and argon, the flow rate of hydrogen is 10 sccm, the flow rate of argon is 20 sccm, the volume ratio of hydrogen to argon is 1:2, the chamber pressure is 28mtorr, the working voltage is 500V, and the magnetron sputtering power is 4kW , the sputtering time is 7min, and the thickness of the obtained diamond-like carbon is 250nm.

(3) The sapphire deposited with the diamond-like layer is placed in an ethanol solution and cleaned for 5 minutes, placed in a suspension of nano-diamond powder with a Zeta potential of about ±50 mV and a particle size of 5 nm, and ultrasonically treated for 30 minutes at an ultrasonic power of 2 kW to carry out crystal implantation. Blow dry with nitrogen and place in a hot wire chemical vapor deposition chamber to deposit the first diamond layer. Use tantalum wire as the hot wire, the diameter is 0.5mm, the total number is 9, the chamber is vacuumed to below 0.1Pa, and the mixed gas is introduced, wherein the flow rate of _H2 is 800sccm, the flow rate of _CH4 is 24sccm, the chamber pressure is 3500Pa, and the growth power 6500W, the deposition temperature is 800°C, the deposition rate is 300nm/h, and the deposition is 1h.

(4) Laser lift-off technology is used to remove sapphire to obtain high thermal conductivity materials, including gallium nitride layer and diamond layer. The bonding force between the gallium nitride layer and the diamond layer was determined to be 800N by Rockwell indentation method, and the nucleation density of diamond in the diamond layer was determined to be 7×10 ¹⁰ pieces/cm ² by scanning electron microscopy.

Example 2

A method for preparing a high thermal conductivity material, comprising the steps of:

(1) Provide silicon carbide as the substrate, clean the silicon carbide with ethanol, place it in a mixture of dilute sulfuric acid and phosphoric acid for etching, and finally place it in an ultra-high vacuum chamber to remove volatile substances on the surface of the substrate , using molecular beam epitaxy to prepare gallium phosphide layers on silicon carbide.

(2) The silicon carbide deposited with the gallium phosphide layer is ultrasonically cleaned with ethanol and deionized water for 10 min successively to remove impurities and blow dry with nitrogen; the dried substrate is ion-coated to obtain a diamond-like carbon with a thickness of 450nm.

(3) Clean the silicon carbide deposited with a diamond-like layer in an ethanol solution for 5 minutes, place it in a suspension of nano-diamond powder with a Zeta potential of about ±50 mV and a particle size of 7 nm, and perform ultrasonic treatment for 40 minutes at an ultrasonic power of 3 kW for crystal planting , dried with nitrogen gas and placed in an atmospheric pressure chemical vapor deposition chamber to deposit and prepare the first diamond layer.

(4) The silicon carbide is removed by a chemical lift-off technique to obtain a gallium phosphide device, including a gallium phosphide layer and a diamond layer. The bonding force between the gallium phosphide layer and the diamond layer was determined to be 600N by Rockwell indentation method, and the nucleation density of diamond in the diamond layer was determined to be 5×10 ¹⁰ /cm ² by scanning electron microscopy.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. a kind of preparation method of highly heat-conductive material characterized by comprising

Substrate is provided, deposits gallium-containing compound layer over the substrate；

Using physical vapour deposition (PVD) on the gallium-containing compound layer depositing diamond-like layer；

The first diamond layer is deposited in the diamond-like rock layers using chemical vapor deposition, in the chemical vapor deposition processes In, the diamond-like rock layers are changed into the second diamond layer；

The substrate is removed, highly heat-conductive material is obtained.

2. the preparation method of highly heat-conductive material as described in claim 1, which is characterized in that the material of the gallium-containing compound layer At least one of sow including gallium nitride, gallium phosphide, GaAs, aluminum gallium arsenide, aluminum gallium phosphide, indium nitridation with AlGaInP.

3. the preparation method of highly heat-conductive material as described in claim 1, which is characterized in that the material of the substrate include silicon, At least one of silicon carbide, aluminium nitride, zinc oxide, GaAs and sapphire.

4. the preparation method of highly heat-conductive material as described in claim 1, which is characterized in that the thickness of the gallium-containing compound layer Be 0.2 μm -1.4 μm, the diamond-like rock layers with a thickness of 200nm-500nm.

5. the preparation method of highly heat-conductive material as described in claim 1, which is characterized in that the deposition of the chemical vapor deposition Rate is 300nm/h-500nm/h.

6. the preparation method of highly heat-conductive material as described in claim 1, which is characterized in that the deposition over the substrate contains Gallium compound layer, comprising:

Contain using described in Metallo-Organic Chemical Vapor deposition, molecular beam epitaxy, liquid growth or vapor deposition over the substrate deposition Gallium compound layer.

7. the preparation method of highly heat-conductive material as described in claim 1, which is characterized in that the removal substrate, comprising:

The substrate is removed using laser lift-off technique, chemical stripping technology or epitaxial lift-off.

8. a kind of highly heat-conductive material, which is characterized in that be made by the described in any item preparation methods of claim 1-7, the height Heat Conduction Material includes gallium-containing compound layer and the diamond layer that is arranged on the gallium-containing compound layer, the diamond layer packet Include first diamond layer and second diamond layer.

9. highly heat-conductive material as claimed in claim 8, which is characterized in that the gallium-containing compound layer and the diamond layer Binding force is 400N-1000N, and the Enhancing Nucleation Density of diamond is (5-10) × 10 in the diamond layer¹⁰A/cm²。

10. a kind of semiconductor devices, which is characterized in that including as made from the described in any item preparation methods of claim 1-7 Highly heat-conductive material or such as described in any item highly heat-conductive materials of claim 8-9, the highly heat-conductive material is as the semiconductor The epitaxial layer of device.