TWI493760B - Light emitting diode and chip on board thereof - Google Patents

Description

Light-emitting diode and package structure on wafer board

The invention relates to a light-emitting diode and a package structure on a wafer board, in particular to a light-emitting diode which can quickly remove a hot spot and enhance an output light rate and a package structure on a wafer board using the same.

In 1962, Nick of General Electric Company. Nick Holonyak Jr. developed the first practical application of Light Emitting Diode (LED), and with the ever-increasing technology, various color LEDs should also be developed. . Under the premise of the pursuit of sustainable development by human beings today, the low power consumption of LEDs and the long-lasting illumination have gradually replaced the indicators used in daily life for lighting or various electrical equipment. Or use of light sources. What's more, the development of light-emitting diodes towards multi-color and high brightness has been applied to large outdoor display billboards or traffic signs.

Taking the conventional blue light-emitting diode as an example, the indium-doped gallium nitride is a conventional multiple quantum wells (MQW), in which the indium atoms having 49 electrons are far larger than the inside of the crystal lattice. The gallium atom and the nitrogen atom make the indium atom easily separated from the crystal lattice, causing the MQW to generate defects and making the blue light emitting diode ineffective. More specifically, the indium atoms present in the gallium nitride crystal lattice cause inverse piezoelectric and internal stress problems, wherein the anti-piezoelectric effect drives the indium atoms away from their equilibrium positions, while the internal stress This will cause a difference in the indium atoms. The above irreversible degradation process will cause the luminous efficiency of the light-emitting diode to rapidly decrease.

In conventional light-emitting diodes, when electrons and holes are recombined, about 1/3 of the energy is radiated in the form of photons, and about 2/3 of the energy is converted into heat energy to escape in a lattice vibration manner. Accordingly, if the thermal energy in the crystal lattice of the light-emitting diode cannot be quickly removed, the problem of deterioration of the light-emitting diode as described above is caused, and the luminous efficiency of the light-emitting diode is rapidly lowered, and accordingly, the applicant proposes In the Republic of China Patent Application Nos. 100146548, 100146551, and 101120872, it is disclosed that a stacked structure or a multilayer structure composed of a diamond-like carbon and a conductive material can effectively improve the heat dissipation efficiency of the light-emitting diode and alleviate or remove the light-emitting diode. Badly affected by thermal expansion. Although the related case reveals that its diamond-like carbon is characterized by its super-hard material, it can quickly remove heat from the light-emitting diode to achieve the overall heat dissipation. However, in fact, as shown in FIG. 1, the hot spot generated in the MQW and having a size smaller than 1 nm is the cause that directly causes the deterioration of the light-emitting diode. Therefore, after the applicant has studied in detail, it is more specifically proposed to limit the distance between the MQW and the diamond-like carbon layer, thereby quickly removing the hot spot from the light-emitting diode through the phonon transfer method, thereby achieving the optimal illumination. The heat dissipation efficiency of the polar body can further maintain the luminous efficiency of the light-emitting diode.

The main object of the present invention is to provide a light-emitting diode which can adjust the structure of the multi-quantum well layer and the carbide layer to dissipate heat through the ultrasonic method during the operation of the light-emitting diode to generate heat. The hot spot in the light-emitting diode is used to stabilize the lattice structure of the light-emitting diode, thereby optimizing the heat-dissipating efficiency of the light-emitting diode and maintaining its luminous efficiency.

To achieve the above object, an aspect of the present invention provides a light emitting diode comprising: a substrate; a semiconductor epitaxial layer on the surface of the substrate, the semiconductor epitaxial layer comprising a first semiconductor epitaxial layer, An active intermediate layer and a second semiconductor epitaxial layer; a reflective layer sandwiched between the semiconductor epitaxial layer and the substrate; a metal layer sandwiched between the reflective layer and the substrate; And a carbide layer interposed between the metal layer and the substrate; wherein the distance between the active intermediate layer and the carbide layer may be 1 to 10 microns.

In the above light-emitting diode of the present invention, the distance between the active intermediate layer and the carbide layer may preferably be 2 μm.

In the above light-emitting diode of the present invention, the reflective layer may be composed of silver, or aluminum, or an alloy thereof. However, it should be understood that the material of the reflective layer is not limited thereto. For example, it may be indium tin oxide (ITO), aluminum zinc oxide (AZO), or zinc oxide (ZnO). ), graphene, nickel (Ni), cobalt (Co), palladium (Pd), platinum (Pt), gold (Au), zinc (Zn), tin (Sn), antimony (Sb), lead ( Pb), copper (Cu), copper silver (CuAg), nickel silver (NiAg), alloys thereof, or metal mixtures thereof. The above-mentioned copper-silver (CuAg) and nickel-silver (NiAg) and the like refer to a eutectic metal, and in addition to achieving a reflection effect, the effect of forming an ohmic contact can also be achieved.

In the above light-emitting diode of the present invention, the metal layer may be titanium, zirconium, molybdenum, or tungsten, and the metal layer has a thickness of 5 nm to 500 nm. Furthermore, The carbide layer can then be diamond-like carbon, graphene, or a combination thereof, and the carbide layer can have a thickness of from 5 nanometers to 1000 nanometers. Accordingly, the metal layer and the carbide layer can be formed in a multi-layered structure stacked on each other. In one aspect of the invention, the metal layer and the carbide layer may each be independently stacked on each other in layers of 1 to 10 to form a multilayer structure in which 2 to 20 layers are stacked on each other.

In the above light-emitting diode of the present invention, the metal layer and the method of forming the carbide layer are not particularly limited. For example, the metal layer or the carbide layer may be formed by arc deposition or sputtering. In one aspect of the invention, the carbide layer can be formed on the metal layer by arc deposition. In another aspect of the invention, the carbide layer is formed on the metal layer by sputtering.

In the above light-emitting diode of the present invention, the carbide layer is formed between the substrate and the semiconductor epitaxial layer, so that the carbide layer needs to have a function of conducting electricity, and therefore, when the selected carbide layer is diamond-like carbon. The carbon drilled material needs to be a conductive tetrahedral structure, and the carbon atom content of the drilled carbon is higher than 95%, and more than 25% of the carbon atoms of the drilled carbon have a twisted tetrahedral bond structure. Accordingly, the metal layer and the carbide layer interposed between the semiconductor epitaxial layer and the substrate can have electrically conductive properties.

In the above light-emitting diode of the present invention, the first semiconductor epitaxial layer is interposed between the reflective layer and the active intermediate layer, and the active intermediate layer is interposed between the first semiconductor epitaxial layer and the first Between two semiconductor epitaxial layers. In one aspect of the present invention, the light emitting diode may be a general-purpose light emitting diode, and the first semiconductor epitaxial layer may be completely covered by the active intermediate layer and the second semiconductor epitaxial layer, wherein The first semiconductor epitaxial layer, the reflection The layer, the metal layer and the carbide layer have the same electrical properties and are electrically connected to each other. The light emitting diode further includes a second electrode disposed on the surface of the second semiconductor epitaxial layer, wherein the second electrode and the second semiconductor epitaxial layer have the same electrical property to be electrically connected to each other. In one embodiment of the invention, the first semiconductor epitaxial layer, the reflective layer, the metal layer and the carbide layer are P-type electrical, and the second semiconductor epitaxial layer and the second electrode are N Type electrical. Accordingly, the light-emitting diode of the present invention can form a general-purpose light-emitting diode.

In the above light-emitting diode of the present invention, the semiconductor epitaxial layer may contain a dopant, and the dopant may be indium. Accordingly, the active intermediate layer of the semiconductor epitaxial layer can be formed into a multiple quantum well layer to improve the efficiency of converting electrical energy into light energy in the light emitting diode, but the present invention does not limit.

In the above light-emitting diode of the present invention, the substrate may comprise an insulating layer and a circuit substrate, wherein the insulating layer may be made of diamond-like carbon, aluminum oxide, ceramic, and diamond-containing epoxy resin. At least one of the group; the circuit substrate can be a metal plate, a ceramic plate or a substrate.

In general, conventional diamond materials can transfer heat at an ultrasonic velocity of 15,000 m/s because of their characteristics of superhard materials, which is equivalent to 5 times the heat transfer rate of silver, and can be reduced if used in a light-emitting diode. The average temperature can evenly distribute its temperature to achieve effective heat dissipation. The important technical feature of the present invention is that the hot spot in the semiconductor epitaxial layer is quickly removed by the ultrasonic heat dissipation method to optimize the luminous efficiency of the light emitting diode. Yes, In the above-described light-emitting diode of the present invention, usually the hot spot is generated as an active intermediate layer of the semiconductor epitaxial layer, and therefore, the distance between the active intermediate layer and the diamond material becomes quite important. For example, in the above-mentioned light-emitting diode of the present invention, diamond-like carbon may be selected as the carbide layer and disposed between the semiconductor epitaxial layer and the substrate, so that the diamond-like carbon can provide the semiconductor epitaxial layer and the ultrasonic wave. The heat dissipation function achieves the purpose of eliminating hot spots. In addition, the diamond-like carbon may also be an insulating layer of the substrate, as long as the diamond-like carbon is close enough to the hot spot to have the effect of ultrasonic heat dissipation, and the position is not particularly limited in the present invention.

Another object of the present invention is to provide a chip on board (COB) for adjusting the structure of a multi-quantum well layer and a carbide layer to operate a light-emitting diode of a package structure on a wafer board. In the process of generating heat, the heat is dissipated by ultrasonic waves, and the hot spot in the light-emitting diode is quickly removed to stabilize the lattice structure of the light-emitting diode, thereby optimizing the heat-dissipating efficiency of the light-emitting diode and maintaining the luminous efficiency thereof. .

To achieve the above object, an aspect of the present invention provides a chip on board (COB) comprising: a circuit carrier comprising at least one electrical connection pad; a semiconductor epitaxial layer; Located on the surface of the circuit carrier, the semiconductor epitaxial layer includes a first semiconductor epitaxial layer, an active intermediate layer, and a second semiconductor epitaxial layer; a reflective layer sandwiched between the semiconductor epitaxial layer and the Between the circuit carriers; a metal layer sandwiched between the reflective layer and the circuit carrier; and a carbide layer interposed between the metal layer and the circuit carrier; wherein the activity The distance between the intermediate layer and the carbide layer may be from 1 to 10 microns.

In the above wafer-on-package structure of the present invention, the distance between the active intermediate layer and the carbide layer may preferably be 2 μm.

In the above wafer-on-package structure of the present invention, the reflective layer may be composed of silver, or aluminum, or an alloy thereof. However, it should be understood that the material of the reflective layer is not limited thereto. For example, it may be indium tin oxide (ITO), aluminum zinc oxide (AZO), or zinc oxide (ZnO). ), graphene, nickel (Ni), cobalt (Co), palladium (Pd), platinum (Pt), gold (Au), zinc (Zn), tin (Sn), antimony (Sb), lead ( Pb), copper (Cu), copper silver (CuAg), nickel silver (NiAg), alloys thereof, or metal mixtures thereof. The above-mentioned copper-silver (CuAg) and nickel-silver (NiAg) and the like refer to a eutectic metal, and in addition to achieving a reflection effect, the effect of forming an ohmic contact can also be achieved.

In the above wafer-on-package structure of the present invention, the metal layer may be titanium, zirconium, molybdenum, or tungsten, and the metal layer has a thickness of 5 nm to 500 nm. Furthermore, the carbide layer may be diamond-like carbon, graphene, or a combination thereof, and the carbide layer may have a thickness of 5 nm to 1000 nm. Accordingly, the metal layer and the carbide layer can be formed in a multi-layered structure stacked on each other. In one aspect of the invention, the metal layer and the carbide layer may each be independently stacked on each other in layers of 1 to 10 to form a multilayer structure in which 2 to 20 layers are stacked on each other.

In the above-described wafer-on-package structure of the present invention, the metal layer and the method of forming the carbide layer are not particularly limited. For example, the metal layer or the carbide layer may be formed by arc deposition or sputtering. In one aspect of the invention, the carbide layer can be formed on the metal layer by arc deposition. to In another aspect of the invention, the carbide layer is formed on the metal layer by sputtering.

In the above wafer-on-package structure of the present invention, since the carbide layer is formed between the circuit carrier and the semiconductor epitaxial layer, the carbide layer needs to have a conductive function, and therefore, when the selected carbide layer is drilled In the case of carbon, the drilled carbon needs to be a conductive tetrahedral structure, and the carbon atom content of the drilled carbon is higher than 95%, and more than 25% of the carbon atoms of the drilled carbon have a twisted tetrahedral bond. structure. Accordingly, the metal layer and the carbide layer interposed between the semiconductor epitaxial layer and the substrate can have electrically conductive properties.

In the above wafer-on-package structure of the present invention, the second semiconductor epitaxial layer is interposed between the reflective layer and the active intermediate layer, and the active intermediate layer is interposed between the first semiconductor epitaxial layer and the Between the second semiconductor epitaxial layers, and the first semiconductor epitaxial layer portion does not cover the active intermediate layer and the second semiconductor epitaxial layer, thereby exposing a portion of the first semiconductor epitaxial layer to provide electrical The purpose of the connection.

In the above-described wafer-on-package structure of the present invention, the metal layer and the multilayer structure formed by the carbide layer may be respectively disposed on the surface of the second semiconductor epitaxial layer and the first semiconductor epitaxial layer for use as an electrode. Electrically connected to the circuit carrier. Specifically, in order to electrically connect the semiconductor epitaxial layer to the circuit carrier, the second semiconductor epitaxial layer and the metal layer and the carbide layer disposed thereon may be P-type electrical; The first semiconductor epitaxial layer and the metal layer and the carbide layer disposed thereon may be N-type electrical. Accordingly, the semiconductor epitaxial layer can be electrically connected to the circuit carrier.

In the above-mentioned wafer-on-package structure of the present invention, a solder layer may be further disposed between the circuit carrier and the carbide layer, so that the semiconductor epitaxial layer can be stably electrically connected to the circuit carrier. board.

In the above wafer-on-package structure of the present invention, the semiconductor epitaxial layer may contain a dopant, and the dopant may be indium. Accordingly, the active intermediate layer of the semiconductor epitaxial layer can be formed into a multiple quantum well layer to improve the efficiency of converting electrical energy into light energy in the light emitting diode, but the present invention does not limit.

In the above wafer-on-package structure of the present invention, the circuit carrier may include an insulating layer and a circuit substrate, wherein the insulating layer is made of a diamond-like carbon, alumina, ceramic, and diamond-containing ring. At least one of the group of oxygen resins; the circuit substrate may be a metal plate, a ceramic plate or a substrate.

In general, conventional diamond materials can transfer heat at an ultrasonic velocity of 15,000 m/s because of their characteristics of superhard materials, which is equivalent to 5 times the heat transfer rate of silver, and can be reduced if used in a light-emitting diode. The average temperature can evenly distribute its temperature to achieve effective heat dissipation. The important technical feature of the present invention is that the hot spot in the semiconductor epitaxial layer is quickly removed by the ultrasonic heat dissipation method to optimize the luminous efficiency of the light emitting diode. Therefore, in the above-described wafer-on-package structure of the present invention, generally, the hot spot is generated as an active intermediate layer of the semiconductor epitaxial layer, and therefore, the distance between the active intermediate layer and the diamond material becomes quite important. For example, in the above package structure of the wafer on-chip of the present invention, diamond-like carbon may be selected as the carbide layer and disposed between the semiconductor epitaxial layer and the circuit carrier, so that the diamond-like carbon can provide the half. The epitaxial layer of the conductor has an ultrasonic heat dissipation function to eliminate hot spots. In addition, the diamond-like carbon may also be an insulating layer of the substrate, as long as the diamond-like carbon is close enough to the hot spot to have the effect of ultrasonic heat dissipation, and the position is not particularly limited in the present invention.

Furthermore, in the above-described package structure on the wafer board of the present invention, the package structure on the wafer board may further include a substrate disposed on the first semiconductor epitaxial layer. Specifically, a flip-chip light-emitting diode can be prepared on the substrate, and the light-emitting diode is electrically connected through a solder layer and packaged onto the circuit carrier board by a flip chip technology to form the photodiode. The package structure on the wafer board. Therefore, if the substrate is a transparent substrate, it can remain on the semiconductor epitaxial layer, and vice versa. In one embodiment of the invention, the substrate may be a sapphire substrate and remain on the semiconductor epitaxial layer, but the invention is not limited thereto.

The embodiments of the present invention are described by way of specific examples, and those skilled in the art can readily appreciate the other advantages and advantages of the present invention. The present invention may be embodied or applied in various other specific embodiments, and various modifications and changes can be made without departing from the spirit and scope of the invention.

The drawings in the embodiments of the present invention are simplified schematic diagrams. However, the illustrations only show elements related to the present invention, and the components shown are not In actual implementation, the number of components, the shape, and the like in actual implementation are a selective design, and the component layout pattern may be more complicated.

Embodiment 1

The object of the present invention is to provide a light-emitting diode which is designed to adjust the structure of the light-emitting diode so that it can be radiated by ultrasonic waves, and the hot spot in the active intermediate layer can be quickly removed, thereby optimizing the light-emitting diode. The body dissipates heat and maintains its luminous efficiency.

2A to 2E are schematic diagrams showing the structure of the preparation process of the light-emitting diode 1 according to the first embodiment of the present invention. The light-emitting diode 1 prepared in the first embodiment is a general-purpose light-emitting diode. First, as shown in FIG. 2A, a substrate 10 is provided which includes an insulating layer 1070 and a circuit substrate 1071. Next, as shown in FIG. 2B, a multilayer structure 15 formed by stacking two metal layers 151 and two carbide layers 152 on each other is formed by sputtering on the substrate 10, wherein the metal layers 151 are titanium. The carbide layers 152 are electrically conductive carbonaceous carbon, and the thicknesses of the metal layers 151 and the carbide layers 152 are each independently 100 nm. Next, referring to FIG. 2C, a reflective layer 11 is formed on the metal layer 151, wherein the reflective layer 11 is aluminum. In addition, since the light-emitting diode 1 is a straight-through light-emitting diode, the metal layer 151, the carbide layer 152, and the reflective layer 11 need to have the same electrical properties. In the first embodiment, the reflective layer 11. The metal layer 151 and the carbide layer 152 are P-type electrical.

Referring to FIG. 2D , a semiconductor epitaxial layer 12 is formed over the reflective layer 11 , wherein the semiconductor epitaxial layer 12 includes a first semiconductor epitaxial layer 121 , an active intermediate layer 122 , and a second semiconductor beam . Crystal layer 123, The first semiconductor epitaxial layer 121, the active intermediate layer 122 and the second semiconductor epitaxial layer 123 are stacked, and the first semiconductor epitaxial layer 121 is sandwiched between the reflective layer 11 and the active intermediate layer. Between 122, the active intermediate layer 122 is sandwiched between the first semiconductor epitaxial layer 121 and the second semiconductor epitaxial layer 123. In the first embodiment, the material of the semiconductor epitaxial layer 12 is indium gallium nitride (InGaN), and the first semiconductor epitaxial layer 121 is a P-type epitaxial layer, and the second semiconductor epitaxial layer 123 is N. Type epitaxial layer. Here, it should be noted that an important technical feature of the present invention is that the structure of the carbide layer is designed to enable heat dissipation by means of ultrasonic waves. Therefore, in the first embodiment, the distance between the active intermediate layer 122 and the at least one carbide layer 152 is designed to be 2 micrometers, so that the carbon as the carbide layer 152 can provide the semiconductor epitaxial layer 12 The heat is dissipated by ultrasonic waves, the heat is quickly removed at an ultrasonic velocity of 15,000 m/s, and the hot spots generated in the active intermediate layer 122 are reduced. In addition, the material suitable for the semiconductor epitaxial layer 12 of the present invention is not limited thereto, and other materials commonly used in the art may also be used. Furthermore, in the first embodiment, the active intermediate layer 122 is a multi-quantum well layer for improving the efficiency of converting electrical energy into light energy in the light-emitting diode 1.

Finally, referring to FIG. 2E, a second electrode 13 is formed on the second semiconductor epitaxial layer 123, wherein the second electrode is N-type electrical. In the light-emitting diode 1 of the first embodiment, the multilayer structure 15 formed of the metal layer 151 and the carbide layer 152 simultaneously functions as an electrode, and the reflective layer 11, the metal layer 151, and the carbonization The electrical property of the object layer 152 is the P-type electrical property of the first semiconductor epitaxial layer 121; the second semiconductor epitaxial layer 123 and the second electrical The pole 13 is of the N-type electrical property, so that the light-emitting diode 1 completed in the first embodiment is a general-purpose light-emitting diode.

Accordingly, as shown in FIG. 2A to FIG. 2E, the light-emitting diode 1 is obtained, comprising: a substrate 10 including an insulating layer 1070, and a circuit substrate 1071; a semiconductor epitaxial layer 12, The semiconductor epitaxial layer 12 includes a first semiconductor epitaxial layer 121, an active intermediate layer 122, and a second semiconductor epitaxial layer 123. The first semiconductor epitaxial layer 121 is interposed. Between the substrate 10 and the active intermediate layer 122, the active intermediate layer 122 is interposed between the first semiconductor epitaxial layer 121 and the second semiconductor epitaxial layer 123; a reflective layer 11 is sandwiched Between the substrate 10 and the semiconductor epitaxial layer 12; a multilayer structure 15 formed by stacking two metal layers 151 and two carbide layers 152, wherein the metal layer 151 is titanium and is located above the multilayer structure 15 The metal layer 151 is interposed between the reflective layer 11 and the substrate 10. The carbide layer 152 is a conductive carbon and the carbide layer 152 under the multilayer structure 15 is sandwiched between the metal layer 151 and Between the substrates 10; wherein the active intermediate layer 122 and the carbide layer The first semiconductor epitaxial layer 121, the reflective layer 11, the metal layer 151, and the carbide layer 152 are P-type electrical, and the second semiconductor epitaxial layer 123 is the same The two electrodes 13 are all N-type electrical. According to this, the light-emitting diode 1 of the first embodiment can be prepared, which is a general-purpose light-emitting diode.

Embodiment 2

In addition to the straight-through light-emitting diode of the first embodiment, the important technical features of the present invention can also be applied to the package structure on the wafer board, thereby optimizing the luminous efficiency.

3A to 3F are schematic diagrams showing the structure of a process for preparing a package structure 300 on a wafer board according to a second embodiment of the present invention. The second embodiment of the present invention first prepares a desired light-emitting diode 3, which is a flip-chip light-emitting device. Diode.

First, as shown in FIG. 3A, a substrate 30 is provided. In the third embodiment, the substrate 30 is a sapphire substrate. Next, as shown in FIG. 3B, a semiconductor epitaxial layer 32 is formed over the substrate 30, wherein the semiconductor epitaxial layer 32 includes a first semiconductor epitaxial layer 321, an active intermediate layer 322, and a second semiconductor. The epitaxial layer 323, wherein the first semiconductor epitaxial layer 321 , the active intermediate layer 322 and the second semiconductor epitaxial layer 323 are stacked, and the first semiconductor epitaxial layer 321 is sandwiched between the substrate 30 and Between the active intermediate layers 322, the active intermediate layer 322 is interposed between the first semiconductor epitaxial layer 321 and the second semiconductor epitaxial layer 323. After the semiconductor epitaxial layer 32 is completed, a portion of the second semiconductor epitaxial layer 323 and a portion of the active intermediate layer 322 are removed to expose the first semiconductor epitaxial layer 321 thereunder. In the second embodiment, the material of the semiconductor epitaxial layer 32 is indium gallium nitride (InGaN), and the first semiconductor epitaxial layer 321 is N-type, and the second semiconductor epitaxial layer 323 is P-type. In addition, the material suitable for the semiconductor epitaxial layer 32 of the present invention is not limited thereto, and other materials commonly used in the art may also be used. Furthermore, in the second embodiment, the active intermediate layer 322 is a multi-quantum well layer for improving the efficiency of converting electrical energy into light energy in the light-emitting diode 3.

Referring to FIG. 3C, a reflective layer 31 is formed over the second semiconductor epitaxial layer 323 which is not removed. In the second embodiment, the reflective layer 31 is silver. However, the step of forming the reflective layer 31 can be selectively performed as desired by those skilled in the art to which the present invention pertains. In other words, if the reflective layer is not intended to be provided, the step of forming the reflective layer 31 can be skipped without performing.

In addition, referring to FIG. 3D, a multilayer structure 35 in which a metal layer 351 and a layer of carbide layer 352 are stacked on each other is formed on the reflective layer 31 by arc deposition, wherein the metal layer 351 is titanium and the metal layer 351 is titanium. The carbide layer 352 is a conductive carbon such as conductive carbon. In addition, a first electrode 34 is formed on the exposed first semiconductor epitaxial layer 321 . The material of the first electrode 34 is not particularly limited as long as it can be electrically connected to the first semiconductor epitaxial layer 321 . can. In the second embodiment, the first electrode 34 is also a multilayer structure (not shown) formed of a metal layer and a carbide layer, and the first electrode 34 and the carbide are adjusted by adjusting the number of layers stacked on each other. Layer 352 forms a coplanar plane. Furthermore, it is considered that the light-emitting diode 3 is electrically connected to the circuit carrier, and the first electrode 34 and the first semiconductor epitaxial layer 321 are N-type electrical; the metal layer 351 and the carbide layer 352 and the second semiconductor epitaxial layer 323 are P-type electrical. Next, as shown in FIG. 3E, a first metal solder layer 36 and a second metal solder layer 37 are formed on the surface of the first electrode 34 and the surface of the carbide layer 352, wherein the first metal solder layer 36 is formed. The surface is coplanar with the surface of the second metal solder layer 37. In this embodiment, the first metal solder layer 36 and the second metal solder layer 37 are composed of a gold layer and a gold tin layer, and the gold tin layer is a eutectic conductive material layer.

Finally, referring to FIG. 3F, the light-emitting diode 3 prepared above is electrically connected and packaged onto a circuit carrier 7 and removed by a laser lift-off technique. The wafer board package structure 300 of this second embodiment is prepared. As shown in FIG. 3F, the on-wafer package structure 300 includes: a circuit carrier 7; and the above-described light-emitting diode 3 is formed through the first metal solder layer 36 and the second metal solder layer 37. The circuit carrier 7 is electrically connected to the circuit carrier 7 , wherein the circuit carrier 7 includes an insulating layer 70 , a circuit substrate 71 , and an electrical connection pad 73 . Here, it should be noted that an important technical feature of the present invention is that the package structure on the wafer board can be dissipated by ultrasonic waves through the carbide layer, so that the distance between the active intermediate layer 322 and the carbide layer 352 is The design is 2 micrometers, so that the drilled carbon, such as the carbide layer 352, can quickly remove the hot spot generated in the active intermediate layer 322 at an ultrasonic velocity of 15,000 m/s by means of ultrasonic heat dissipation.

In addition, in the package structure 300 on the wafer board, the first metal solder layer 36 and the second metal solder layer 37 and the circuit can be formed by soldering through the solder 72 formed on the surface of the electrical connection pad 73. The electrical connection pads 73 of the carrier 7 are electrically connected.

Accordingly, as shown in FIG. 3A to FIG. 3F, the above-described wafer-on-board package structure 300 includes: a circuit carrier 7; a semiconductor epitaxial layer 32, which is located on the circuit carrier 7, the semiconductor The epitaxial layer 32 includes a first semiconductor epitaxial layer 321 , an active intermediate layer 322 , and a second semiconductor epitaxial layer 323 ; a reflective layer 31 is sandwiched between the circuit carrier 7 and the second semiconductor Between the epitaxial layers 323, a metal layer 351 is sandwiched between the reflective layer 31 and Between the circuit carriers 7; a carbide layer 352 is interposed between the metal layer 351 and the circuit carrier; and a first electrode 34 is disposed on the exposed portion of the first semiconductor epitaxial The second semiconductor epitaxial layer 323 is interposed between the reflective layer 31 and the active intermediate layer 322, and the active intermediate layer 322 is sandwiched between the first semiconductor epitaxial layer 321 and the Between the second semiconductor epitaxial layers 323, and the semiconductor epitaxial layer 32 is encapsulated on the circuit carrier 7 via a first metal solder layer 36 and a second metal solder layer 37, and the active intermediate layer 322 and the The distance between the carbide layers 352 is 2 microns. In addition, the first electrode 34 and the first semiconductor epitaxial layer 321 are N-type electrical; the metal layer 351, the carbide layer 352 and the second semiconductor epitaxial layer 323 are P-type electrical.

Embodiment 3

Please refer to FIG. 4 , which is a schematic structural diagram of the package structure 400 on the wafer board of the third embodiment. The third embodiment is substantially similar to the preparation process of the second embodiment, except that the prepared light-emitting diode 3 is electrically connected and packaged on the circuit carrier board 7, since the substrate 30 used is sapphire. The substrate, therefore, can be completed without removing the substrate 30.

Accordingly, as shown in FIG. 4, the wafer-on-board package structure 400 obtained in the third embodiment includes: a circuit carrier board 7; a semiconductor epitaxial layer 32, which is located on the circuit carrier board 7, The semiconductor epitaxial layer 32 includes a first semiconductor epitaxial layer 321 , an active intermediate layer 322 , and a second semiconductor epitaxial layer 323 ; a reflective layer 31 is sandwiched between the circuit carrier 7 and the second Between the semiconductor epitaxial layers 323, a metal layer 351 is sandwiched between the reflective layer 31 and a first carbide electrode 352 is disposed between the metal layer 351 and the circuit carrier 7; a first electrode 34 is disposed on the first semiconductor epitaxial layer 321; And a substrate 30 disposed on the first semiconductor epitaxial layer 321; wherein the second semiconductor epitaxial layer 323 is interposed between the reflective layer 31 and the active intermediate layer 322, the active intermediate layer 322 The first semiconductor epitaxial layer 321 is interposed between the first semiconductor epitaxial layer 321 and the second semiconductor epitaxial layer 323, and the semiconductor epitaxial layer 32 is encapsulated via a first metal solder layer 36 and a second metal solder layer 37. The circuit carrier 7 has a distance between the active intermediate layer 322 and the carbide layer 352 of 2 microns. In addition, the first electrode 34 and the first semiconductor epitaxial layer 321 are N-type electrical; the metal layer 351, the carbide layer 352 and the second semiconductor epitaxial layer 323 are P-type electrical.

Embodiment 4

The fourth embodiment is substantially similar to the preparation process of the second embodiment described above, except that the insulating layer of the circuit carrier used is a type of drilled carbon (the same composition as the carbide layer). Accordingly, the package structure on the wafer board completed in the fourth embodiment can simultaneously perform ultrasonic heat dissipation through the carbide layer and the insulating layer.

Comparative example one

This first comparative example is substantially the same as the first embodiment except that the straight-through light-emitting diode of the first comparative example does not contain a carbide layer. Accordingly, the straight-through light-emitting diode obtained in Comparative Example 1 cannot transmit ultrasonic waves through the carbide layer.

Comparative example two

This comparative example is substantially the same as that of the second embodiment except that the package structure on the wafer board of the comparative example does not contain a carbide layer. Accordingly, the package structure on the wafer board obtained by the comparative example cannot be ultrasonically dissipated through the carbide layer.

Test Example 1

In the test example, the light field distribution of the straight-through light-emitting diodes prepared in Example 1 and Comparative Example 1 was analyzed by a near-field optical microscope under the same conditions of energized light emission to show defects in hot spots. The situation. 5A and 5B are light field analysis results of Example 1 and Comparative Example 1, respectively, wherein no black spots due to non-luminescence are observed in FIG. 5A, and the straight-through formula of Example 1 is shown. In the case of light-emitting illuminating (350 mA, 7 minutes), there is no defect due to hot spots; otherwise, in FIG. 5B, it can be found at the center due to non-lighting. The black dots are shown under the same conditions, and the straight-through light-emitting diode of Comparative Example 1 has defects due to hot spots.

Test example 2

In the second test example, the temperature of the package structure on the wafer on the second embodiment and the second embodiment was continuously energized (350 mA) for 16 minutes under the same conditions of energized light emission, wherein the second embodiment The temperature of the package structure on the wafer board is 61.12 ° C to 68.21 ° C; and the temperature of Comparative Example 2 is 72.44 ° C to 84.11 ° C, which is much higher than the temperature of the second embodiment. Therefore, from this As can be seen from the results, the package structure on the wafer board having the ultrasonic heat dissipation function according to the present invention can dissipate heat by ultrasonic waves, rapidly remove heat, and reduce hot spots generated in the semiconductor epitaxial layer.

Test Example 3

In the third test example, the package structure on the wafer board prepared in Example 2 and Comparative Example 2 was analyzed by a T3Ster thermal resistance meter at 25 ° C to show the state of heat conduction. Please refer to FIG. 6A and FIG. 6B , which are diagrams of the thermal resistance analysis results of the second embodiment and the second comparative example, wherein the horizontal axis is the thermal resistance and the unit is K/W; the vertical axis is the heat capacity, and the unit is Ks/W. . Please refer to FIG. 6A , which is a thermal resistance analysis result according to Embodiment 2 of the present invention, wherein the thermal resistance between the circuit carrier and the LED is 0.98 K/W. Referring to FIG. 6B, the thermal resistance analysis result of the second comparative example of the present invention shows that the thermal resistance between the circuit carrier and the light-emitting diode is 1.51 K/W. Therefore, when the package structure on the wafer board contains a carbide layer formed of diamond-like carbon, and the distance between the carbide layer and the active intermediate layer is 2 micrometers, the thermal resistance between the two can be effectively reduced.

Test example four

In the test example 4, the temperature distribution of the straight-through light-emitting diode wafers prepared in Example 1 and Comparative Example 1 was analyzed by a thermal image analyzer under the same energized light-emitting conditions. Please refer to FIG. 7A and FIG. 7B , which are the temperature distribution result diagrams of the first embodiment and the first comparative example, respectively. As shown in FIGS. 7A and 7B, under the same energized light-emitting condition (350 mA), the temperature of the straight-through light-emitting diode of the first embodiment is about 58 ° C to 60 ° C; otherwise, the straight-through light of the comparative example 1 The temperature of the polar body is about 73 ° C to 76 ° C. Therefore, the above results can be It is known that the straight-through light-emitting diode having the ultrasonic heat dissipation function manufactured according to the present invention can dissipate heat by ultrasonic waves, rapidly remove heat, and reduce hot spots generated in the semiconductor epitaxial layer.

Test Example 5

In the fifth test example, the temperature distribution of the package structure on the wafer board prepared in Example 4 and Comparative Example 2 was analyzed by a thermal image analyzer under the same energized light-emitting conditions. Please refer to FIGS. 8A and 8B , which are graphs of temperature distribution results of Example 4 and Comparative Example 2, respectively. As shown in FIGS. 8A and 8B, under the same energized lighting condition (700 mA), the temperature of the package structure on the wafer on the fourth embodiment is about 55 ° C to 59 ° C; otherwise, the package structure on the wafer board of Comparative Example 2 The temperature is about 65 ° C to 77 ° C. Therefore, from the above results, when the carbide layer and the insulating layer simultaneously contain diamond-like carbon, the synergistic effect produced by the two will make the package structure on the wafer board prepared by the invention have better heat dissipation effect. Accordingly, the on-wafer package structure having the ultrasonic heat dissipation function manufactured according to the present invention can surely dissipate heat by ultrasonic waves, provide heat removal, quickly remove heat, and reduce hot spots generated in the semiconductor epitaxial layer.

Accordingly, the results of the above Test Examples 1 to 5 show that the straight-through light-emitting diode of the present invention and the package structure on the wafer board have a diamond-like carbon and adjust the distance between the active intermediate layer and the diamond-like carbon to be 1 to 10 Within the micrometer, the carbon can be quickly removed by the ultrasonic heat dissipation method, and the hot spot generated in the active intermediate layer is quickly removed, thereby improving the overall thermal stability of the package structure on the wafer board, thereby improving the luminous efficiency and prolonging the life of the product. .

In summary, the light-emitting diode of the present invention and the package structure on the wafer board using the same have a structure design of ultrasonic heat dissipation, and can quickly remove the generated hot spot during the process of generating heat of the light-emitting diode. In order to stabilize its lattice structure, to optimize its heat dissipation efficiency to maintain its luminous efficiency.

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

1,3‧‧‧Lighting diode

10,30‧‧‧Substrate

11,31‧‧‧reflective layer

12,32‧‧‧Semiconductor epitaxial layer

121,321‧‧‧First semiconductor epitaxial layer

122,322‧‧‧Active intermediate layer

123,323‧‧‧Second semiconductor epitaxial layer

13‧‧‧second electrode

34‧‧‧First electrode

151,351‧‧‧metal layer

152,352‧‧‧Carbide layer

15,35‧‧‧Multilayer structure

36‧‧‧First metal solder layer

37‧‧‧Second metal soldering layer

7‧‧‧Circuit carrier board

1070, 70‧‧‧ insulation

1071, 71‧‧‧ circuit board

72‧‧‧ solder

73‧‧‧Electrical connection pads

300,400‧‧‧ wafer board package structure

FIG. 1 is a schematic diagram showing the size of a heat source generated in a light-emitting diode corresponding to a heat source temperature.

2A to 2E are schematic structural views showing a process for preparing a light-emitting diode according to Embodiment 1 of the present invention.

3A to 3F are schematic views showing the preparation process of the package structure on the wafer board according to the second embodiment of the present invention.

4 is a schematic structural view of a package structure on a wafer board according to a third embodiment of the present invention.

5A and 5B are diagrams showing the results of light field analysis of Test Example 1 of the present invention.

6A and 6B are graphs showing the results of thermal resistance analysis in Test Example 3 of the present invention.

7A and 7B are graphs showing the results of temperature distribution in Test Example 4 of the present invention.

8A and 8B are graphs showing the results of temperature distribution in Test Example 5 of the present invention.

300‧‧‧Package on the wafer board

31‧‧‧reflective layer

32‧‧‧Semiconductor epitaxial layer

321‧‧‧First semiconductor epitaxial layer

322‧‧‧Active intermediate layer

323‧‧‧Second semiconductor epitaxial layer

34‧‧‧First electrode

35‧‧‧Multilayer structure

351‧‧‧metal layer

352‧‧‧Carbide layer

36‧‧‧First metal solder layer

37‧‧‧Second metal soldering layer

7‧‧‧Circuit carrier board

70‧‧‧Insulation

71‧‧‧ circuit board

72‧‧‧ solder

73‧‧‧Electrical connection pads

Claims (14)

A chip on board (COB) comprising: a circuit carrier comprising at least one electrical connection pad; a semiconductor epitaxial layer on the surface of the circuit carrier, the semiconductor epitaxial The layer includes a first semiconductor epitaxial layer, an active intermediate layer, and a second semiconductor epitaxial layer; a reflective layer sandwiched between the semiconductor epitaxial layer and the circuit carrier; a metal layer, a tie between the reflective layer and the circuit carrier; and a carbide layer interposed between the metal layer and the circuit carrier; wherein the metal layer and the carbide layer are The multilayer structure is stacked on each other, and the distance between the active intermediate layer and the carbide layer is 1 to 10 μm. The wafer-on-package structure according to claim 1, wherein the distance between the active intermediate layer and the carbide layer is 2 μm. The wafer-on-package structure of claim 1, wherein the metal layer is titanium, zirconium, molybdenum, or tungsten. The wafer-on-package structure of claim 1, wherein the carbide layer is diamond-like carbon, graphene, or a combination thereof. The wafer-on-package structure according to claim 1, wherein the carbon-based carbonaceous structure is a conductive tetrahedral structure, and the carbon-like carbonaceous material The carbon atom content is higher than 95%, and more than 25% of the carbon atoms of the drilled carbon have a twisted tetrahedral bond structure. The wafer-on-package structure according to claim 1, wherein the second semiconductor epitaxial layer is interposed between the reflective layer and the active intermediate layer, and the active intermediate layer is interposed therebetween. a semiconductor epitaxial layer and the second semiconductor epitaxial layer, and the first semiconductor epitaxial layer portion does not cover the active intermediate layer and the second semiconductor epitaxial layer. The wafer-on-package structure of claim 1, wherein the semiconductor epitaxial layer comprises a dopant, and the dopant is indium. The wafer-on-board package structure of claim 1, wherein the circuit carrier comprises an insulating layer and a circuit substrate, the insulating layer is selected from the group consisting of diamond-like carbon, alumina, ceramic, and At least one of the groups of diamond-containing epoxy resins. The package structure on a wafer board according to claim 8, wherein the circuit substrate is a metal plate, a ceramic plate or a substrate. The package structure on a wafer board according to claim 1, wherein the second semiconductor epitaxial layer is P-type electrical, and the first semiconductor epitaxial layer is N-type electrical. The wafer-on-package structure of claim 1, wherein the carbide layer is used to provide ultrasonic radiation dissipation of the semiconductor epitaxial layer. The package structure on a wafer board according to claim 1, further comprising a substrate disposed on the first semiconductor epitaxial layer. The wafer-on-package structure of claim 12, wherein the substrate is a sapphire substrate. The package structure on a wafer board according to claim 1, further comprising a solder layer disposed between the circuit carrier and the carbide layer.