TWI392117B - Light emitting diode with a diamond film and manufacturing method thereof - Google Patents

Description

Light-emitting diode with diamond film and manufacturing method thereof

The present invention relates to a light-emitting diode and a method of manufacturing the same, and more particularly to a light-emitting diode having a diamond film and a method of manufacturing the same.

Electronic components are accompanied by high heat during operation. The higher the efficiency of electronic components, the higher the temperature of the electronic components. In the case of central processing units, the central processing unit developed by the technology has been operating at billions of ohms. (GHz), the high heat generated by it has been quickly dissipated by conventional heat sinks.

In addition, in the past decade, light-emitting semiconductor components, such as light-emitting diodes (LEDs), laser diodes, etc., have advanced by leaps and bounds, and the power used is getting higher and higher, and the heat energy generated is also getting higher and higher. It has reached the upper limit that semiconductor light sources can withstand. In order to avoid damage to components due to high heat, new heat dissipation materials or heat dissipation methods are urgently needed to be developed.

The biggest characteristics of the light-emitting diode are: no need for warming time, fast response, small size, low power consumption, low vibration, low pollution, suitable for mass production, high reliability, easy to make small or array with the needs of the application. Component. However, because the light-emitting diode is solid-state illumination, that is, the power is applied by the wafer, and the quantum excited state returns energy (light), but in the process of light emission, the light energy in the wafer cannot be completely transmitted to the outside, and the energy cannot be emitted. The inside of the wafer and the package body are absorbed to form heat. If heat is not dissipated, the accumulation of heat will affect the efficiency and life of the wafer. Therefore, it is necessary to use the high-efficiency light-emitting diode for lighting equipment to solve the problem of heat dissipation.

The light-emitting diode structure disclosed in the above-mentioned patent application of the Japanese Patent No. 96111093, the substrate and the light-emitting layer are bonded to each other by a metal layer, and through the good heat conduction characteristics of the diamond layer, the light is emitted. The heat of the layer is radiated to the first substrate, but the diamond layer is polished during the manufacturing process, and the first substrate is not a material with high thermal conductivity, so the overall heat dissipation efficiency still has room for improvement.

The heat dissipating device for a semiconductor device disclosed in US Patent No. 20040238946 utilizes a diamond layer or a material structure containing diamonds, such as a diamond layer and a ceramic layer or a mixed layer of diamond and ceramic particles, and a polymer adhesive. It is attached to a metal heat sink for heat dissipation. However, the disadvantage is that the polymer adhesive used is not a material with high thermal conductivity, so the overall heat dissipation efficiency is not good.

In the prior art, since a plurality of metal layers must be sequentially formed on the diamond film, the diamond film must be polished to a desired flatness to facilitate the bonding between the diamond film and the metal layer, whereas the diamond material has the highest hardness. Therefore, the polishing process of the diamond film will take a considerable amount of time and cost.

In view of the problem in the prior art that the heat dissipation effect is reduced by contacting the germanium substrate with the heat sink, and the diamond film is polished in the process, the present invention provides a light emitting diode having a diamond film and a manufacturing method thereof. The polishing process of the diamond film is simplified, and the diamond substrate is replaced by the diamond substrate to contact the heat sink, and the contact area of the rough diamond surface is increased, and the heat dissipation area of the diamond film is increased to improve the light emission of the prior art. The problem of poor heat dissipation efficiency caused by the use of the polar body.

The method for manufacturing a light-emitting diode of the present invention comprises: providing a temporary substrate; forming a diamond film on the temporary substrate, the diamond film having a first side and a second side, the first side being opposite to the second side, One side is attached to the temporary substrate, and the second side is a rough surface; the temporary substrate is removed; a third metal layer is formed on the first side of the diamond film; and a first metal layer is formed Providing a substrate; forming a light-emitting layer on the substrate; forming a second metal layer on the light-emitting layer; bonding the first metal layer and the second metal layer; and finally removing the substrate.

The invention has the advantages of simplifying the process of polishing the diamond film in the prior art, and contacting the diamond film with the heat sink to reduce the excess thermal barrier of the ruthenium substrate, and the rough surface formed by the diamond growth surface is increased and The contact area of the heat sink. In addition, the diamond lattice arrangement close to the rough surface is better, and the heat of the luminescent layer can be guided to the heat sink by the characteristics of the gradient difference of the lattice arrangement, thereby achieving the purpose of improving the heat dissipation efficiency.

The detailed features and advantages of the present invention are set forth in the Detailed Description of the Detailed Description of the <RTIgt; </ RTI> <RTIgt; </ RTI> </ RTI> </ RTI> <RTIgt; The above objects and advantages of the present invention will be readily understood by those skilled in the art.

The above description of the present invention and the following description of the embodiments of the present invention are intended to illustrate and explain the principles of the invention.

In order to further improve the object, structure, features, and functions of the present invention The solution is described in detail below in conjunction with the embodiment.

Referring to "1st" and "2A" to "2F", the schematic diagram of the production process and the flow chart of the steps of the light-emitting diode of the present invention are shown. As shown in "Fig. 1" and "Fig. 2A", the diamond film 210 has a first side surface 2101 and a second side surface 2102, and the second side surface 2102 is a diamond growth surface, so that the second side surface 2102 is compared with The first side surface 2101 is a rough surface, and the first side surface 2101 is attached to the temporary substrate 200 to form a diamond film 210 on a temporary substrate 200 (step 100), wherein the diamond film 210 is chemically gas. A chemical vapor deposition (CVD), such as Microwave Plasma assisted Chemical Vapor Deposition (MPCVD), is formed on the temporary substrate 200, and the material thereof includes single crystal diamonds and polycrystalline diamonds. Or materials such as diamond-like carbon (DLC), but not limited to this, and the material of the temporary substrate 200 may be selected from bismuth (Si), tantalum carbide (SiC), gallium arsenide (GaAs), alumina or sapphire. Such materials, but not limited to this.

Next, as shown in FIG. 1 and FIG. 2B, the temporary substrate 200 is removed (step 110), and a third metal layer 260 is formed on the first side 2101 of the diamond film 210 (step 120). . The third metal layer 260 is sputter, thermal evaporation, e-gun evaporation, chemical vapor deposition (CVD) or physical vapor deposition ( Physical Vapor Deposition, PVD), etc., formed on the diamond film 210, and the material of the third metal layer 260 includes nickel (Ni), titanium (Ti), gold (Au), silver (Ag), chromium (Cr) Or aluminum (Al) and alloys thereof, wherein the bond energy of the material constituting the third metal layer 260 is less susceptible to heat After the process, the strength of the strength is weakened. In addition, the third metal layer 260 has a thickness of less than 2,000 nanometers (nm), preferably between 50 nanometers and 100 nanometers. The thickness of the present invention has a lower characteristic contact resistance and Strong film bonding strength.

Next, as shown in FIG. 1 and FIG. 2C, a first metal layer 220 is formed on the third metal layer 260 (step 130), wherein the first metal layer 220 can be sputtered and steamed. Forming on the third metal layer 260 by plating, electron beam evaporation, chemical vapor deposition or physical vapor deposition, the material of the first metal layer 220 includes gold (Au), silver (Ag), palladium (Pd), Indium (In), titanium (Ti), chromium (Cr) or nickel (Ni) having a thickness of less than 2 micrometers (μm). Wherein, the first metal layer 220 composed of gold (Au) or silver (Ag) can form a continuous network shape to uniformly disperse current after the processing procedure, thereby contributing to the conductivity of the film, and the present invention The exposed thickness has a lower characteristic contact resistance.

Next, as shown in "FIG. 1" and "2D", a substrate 230 is provided, and a light-emitting layer 240 is formed on the substrate 230 (step 140). Next, as shown in FIG. 1 and FIG. 2E, a second metal layer 250 is formed on the light-emitting layer 240 (step 150), wherein the second metal layer 250 is sputtered, thermally evaporated, and electronically. Beam evaporation, chemical vapor deposition or physical vapor deposition is formed on the light-emitting layer 240, and the material of the second metal layer 250 includes gold (Au), silver (Ag), palladium (Pd), indium (In ), titanium (Ti), chromium (Cr) or nickel (Ni) having a thickness of not more than 2 micrometers (μm). Wherein, the second metal layer 250 composed of gold (Au) or silver (Ag) can form a continuous network shape to uniformly disperse current after the processing procedure, thereby contributing to the conductivity of the film, and the present invention The exposed thickness has a lower characteristic contact resistance.

As shown in "Fig. 1" and "Fig. 2F", the first metal layer 220 and the second metal layer 250 are joined to each other (step 160), wherein the direction of the arrow shown in "2F" is A metal layer 220 and a second metal layer 250 are hot pressed at a temperature of 200 ° C to 300 ° C for about 30 minutes, so that the diamond film 210 is bonded to the substrate 230, wherein the metal of the first metal layer 220 and the second metal layer 250 The composition materials are similar and the energy gap is low, and the diamond film 210 and the substrate 230 are closely bonded by the metal bonding between the first metal layer 220 and the second metal layer 250 by the hot pressing. Finally, as shown in "FIG. 1", the substrate 230 is removed (step 170) to form the light-emitting diode of the present invention.

Please refer to FIG. 3, which is a schematic cross-sectional view of the light emitting diode structure 10 of the present invention. The light emitting diode structure 10 includes a diamond layer 210, a third metal layer 260, a first metal layer 220, a second metal layer 250, and a light emitting layer 240. The diamond film 210 has a rough surface, and the third metal layer 260 is formed on the diamond film 210. The first metal layer 220 is formed on the third metal layer 260, and the second metal layer 250 is formed on the first surface. On the metal layer 220, the light emitting layer 240 is formed on the second metal layer 250. The present invention forms the third metal layer 260 between the diamond film 210 and the first metal layer 220, thereby enhancing the adhesion between the diamond film 210 and the first metal layer 220.

Fig. 4 is a schematic cross-sectional view showing the light-emitting diode of the present invention in combination with a heat sink. The light-emitting diode of the present invention attaches the diamond film 210 to the heat sink 30 by the heat-dissipating paste 20 or other package bonding material. Since the second side surface 2102 of the diamond film is a rough surface, the heat-dissipating paste 20 can be added. The contact area, in turn, increases the bonding force with the thermal grease 20 and improves the heat dissipation efficiency. In addition, the diamond lattice arrangement close to the rough surface is better, and the light-emitting layer 240 can be arranged by the gradient difference of the lattice arrangement thereof. The generated heat is sequentially guided to the second side surface 2102 of the diamond film via the second metal layer 250, the first metal layer 220, and the third metal layer 260, thereby improving heat dissipation efficiency.

In summary, the light-emitting diode system of the present invention utilizes the characteristic that the first side surface 2101 of the diamond film formed on the temporary substrate 200 is a flat surface, and the third metal layer 260 and the first metal layer 260 can be formed directly on the first side surface 2101. a metal layer 220 without polishing the diamond film 210, and the light-emitting diode and the heat sink 30 are in contact with the heat sink 30 by the heat-dissipating paste 20, wherein the second side of the diamond film has a rough surface The contact area with the thermal grease 20 is increased to achieve an effect of increasing heat dissipation efficiency. In addition, the diamond film 210 has a lattice alignment gradient characteristic, and the heat generated by the light-emitting layer 240 is guided to the metal heat sink 30 to achieve the purpose of improving heat dissipation efficiency.

Although the present invention has been disclosed above in the foregoing embodiments, it is not intended to limit the invention. It is within the scope of the invention to be modified and modified without departing from the spirit and scope of the invention. Please refer to the attached patent application for the scope of protection defined by the present invention.

10‧‧‧Diamond film light-emitting diode

20‧‧‧ Thermal grease

30‧‧‧ radiator

100‧‧‧Forming a diamond film on a temporary substrate

110‧‧‧Remove temporary substrate

120‧‧‧Form a third metal layer on the diamond film

130‧‧‧ Forming a first metal layer on the third metal layer

140‧‧‧ Forming a luminescent layer on the substrate

150‧‧‧ forming a second metal layer on the light-emitting layer

160‧‧‧ joining the first metal layer and the second metal layer

170‧‧‧Remove the substrate

200‧‧‧temporary substrate

210‧‧‧Diamond film

2101‧‧‧ first side

2102‧‧‧ second side

220‧‧‧First metal layer

230‧‧‧Substrate

240‧‧‧Lighting layer

250‧‧‧Second metal layer

260‧‧‧ Third metal layer

1 is a schematic diagram showing a manufacturing process of a light-emitting diode of the present invention; FIGS. 2A to 2F are schematic flow charts showing a step of fabricating a light-emitting diode according to an embodiment of the present invention; and FIG. 3 is a light-emitting diode of the present invention. A schematic cross-sectional view of a polar body; and FIG. 4 is a schematic cross-sectional view of the light-emitting diode of the present invention in combination with a heat sink.

100‧‧‧Forming a diamond film on a temporary substrate

110‧‧‧Remove temporary substrate

120‧‧‧Form a third metal layer on the diamond film

130‧‧‧ Forming a first metal layer on the third metal layer

140‧‧‧ Forming a luminescent layer on the substrate

150‧‧‧ forming a second metal layer on the light-emitting layer

160‧‧‧ joining the first metal layer and the second metal layer

170‧‧‧Remove the substrate

Claims (12)

A method for manufacturing a light-emitting diode includes the steps of: providing a temporary substrate; forming a diamond film on the temporary substrate, the diamond film having a first side and a second side, the first side Relative to the second side, the first side is attached to the temporary substrate, and the second side is a rough surface; the temporary substrate is removed; and a third metal layer is formed on the diamond film Forming a first metal layer on the third metal layer; providing a substrate; forming a light-emitting layer on the substrate; forming a second metal layer on the light-emitting layer; bonding the first a metal layer and the second metal layer; and removing the substrate. The manufacturing method of claim 1, wherein the method of forming the third metal layer comprises sputtering, thermal evaporation, electron beam evaporation, chemical vapor deposition, or physical vapor deposition. The manufacturing method of claim 1, wherein the third metal layer material is selected from the group consisting of nickel, titanium, gold, silver, chromium or aluminum and alloys thereof. The manufacturing method according to claim 1, wherein the third metal layer has a thickness of 2000 nm or less. The manufacturing method of claim 1, wherein the third metal layer is thick The degree is between 50 nm and 100 nm. The manufacturing method of claim 1, wherein the method of forming the first metal layer comprises sputtering, thermal evaporation, electron beam evaporation, chemical vapor deposition, or physical vapor deposition. The manufacturing method of claim 1, wherein the first metal layer material is selected from the group consisting of gold, silver, palladium, indium, titanium, chromium or nickel. The manufacturing method according to claim 1, wherein the first metal layer has a thickness of 2 μm or less. The manufacturing method of claim 1, wherein the method of forming the second metal layer comprises sputtering, thermal evaporation, electron beam evaporation, chemical vapor deposition, or physical vapor deposition. The manufacturing method of claim 1, wherein the second metal layer material is selected from the group consisting of gold, silver, palladium, indium, titanium, chromium or nickel. The manufacturing method according to claim 1, wherein the second metal layer has a thickness of 2 μm or less. The manufacturing method of claim 1, wherein the method of forming the diamond film comprises chemical vapor deposition or microwave plasma assisted chemical vapor deposition.