CN106992234A - Led device - Google Patents

Abstract

The present invention provides an LED device comprising: the device comprises a substrate, an epitaxial layer, a transparent conducting layer, an insulating reflecting layer, a first electrode and a second electrode; the epitaxial layer comprises a first type semiconductor layer positioned on the substrate and a second type semiconductor layer positioned on the surface of a partial area of the first type semiconductor layer; the first electrode is positioned on the surface of a partial region of the first type semiconductor layer, and the second electrode is positioned on the surface of a partial region of the second type semiconductor layer; the insulating reflecting layer covers the surface of the epitaxial layer; the transparent conductive layer is positioned between the second type semiconductor layer and the insulating reflecting layer. By the scheme provided by the invention, the structure and the preparation process of the LED device can be effectively simplified, and the production yield is improved.

Description

LED device

technical field

The invention relates to the technical field of semiconductors, in particular to an LED device.

Background technique

A light-emitting diode (Light-Emitting Diode, referred to as LED) is a semiconductor electronic component that can convert electrical energy into light energy. With the continuous advancement of technology, due to the characteristics of low power consumption, low heat, no delay in starting, and high brightness, LEDs are widely used in the fields of display, TV lighting decoration and lighting.

However, the structures of current LED devices, especially flip-chip LED devices, are generally complicated, and the corresponding manufacturing process is relatively cumbersome, resulting in a low production yield.

Contents of the invention

The invention provides an LED device, which is used to solve the problem that the structure and technological process of the existing LED device are too complex and cumbersome.

The present invention provides an LED device, comprising: a substrate, an epitaxial layer, a transparent conductive layer, an insulating reflective layer, and a first electrode and a second electrode; wherein, the epitaxial layer includes a first type semiconductor on the substrate layer and the second type semiconductor layer located on the partial area surface of the first type semiconductor layer; the first electrode is located on the partial area surface of the first type semiconductor layer, and the second electrode is located on the second on the surface of a partial region of the type semiconductor layer; the insulating reflective layer covers the surface of the epitaxial layer; the transparent conductive layer is located between the second type semiconductor layer and the insulating reflective layer.

In the LED device provided by the present invention, the surfaces of the first-type semiconductor layer and the second-type semiconductor layer have a stepped structure, and the surfaces of the first-type semiconductor layer and the second-type semiconductor layer are respectively provided with a first electrode and a second electrode. The epitaxial layer covers the exposed surface of the epitaxial layer, and the transparent conductive layer is arranged between the second-type semiconductor layer and the insulating reflection layer, which effectively simplifies the structure and preparation process of the LED device, and improves the production yield.

Description of drawings

FIG. 1 is a schematic cross-sectional structure diagram of an LED device provided by Embodiment 1 of the present invention;

2A is a schematic cross-sectional structure diagram of an LED device provided by Embodiment 2 of the present invention;

2B is a schematic top view of the transparent conductive layer in Embodiment 2 of the present invention;

3A is a schematic cross-sectional structure diagram of an LED device provided by Embodiment 3 of the present invention;

3B is a schematic top view of the transparent conductive layer in Embodiment 3 of the present invention;

FIG. 4A is a schematic cross-sectional structure diagram of an LED device provided by Embodiment 4 of the present invention;

FIG. 4B is a schematic top view of the structure of FIG. 4A;

FIG. 5A is a schematic top view structure diagram of an LED device provided by Embodiment 5 of the present invention;

FIG. 5B is a schematic top view of another LED device provided by Embodiment 5 of the present invention;

FIG. 5C is a schematic top view of another LED device provided by Embodiment 5 of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. For convenience of description, the sizes of different layers and regions are enlarged or reduced, so the sizes and ratios shown in the drawings do not necessarily represent actual sizes, nor do they reflect the proportional relationship of sizes.

FIG. 1 is a schematic cross-sectional structure diagram of an LED device provided by Embodiment 1 of the present invention. As shown in FIG. and the second electrode 16; wherein,

The epitaxial layer 12 includes a first-type semiconductor layer 121 on the substrate 11 and a second-type semiconductor layer 122 on the surface of a part of the first-type semiconductor layer 121;

The first electrode 15 is located on the partial area surface of the N-type semiconductor layer 121, and the second electrode 16 is located on the partial area surface of the P-type semiconductor layer 122; the insulating reflective layer 14 covers the surface of the epitaxial layer 12; the transparent conductive layer 13 is located on the second between the type semiconductor layer 122 and the insulating reflective layer 14 .

Wherein, the substrate 11 may specifically be a transparent substrate to realize the luminous effect of the LED device. Optionally, the substrate 11 may include but not limited to any one of sapphire, SiC, GaN, and AlN. The epitaxial layer 12 can be a semiconductor element, such as monocrystalline silicon, polycrystalline silicon or silicon with an amorphous structure, or a mixed semiconductor structure, such as silicon carbide, indium antimonide, lead telluride, indium arsenide, indium phosphide, arsenic Gallium or gallium antimonide or silicon germanium (SiGe), alloy semiconductors or combinations thereof. In addition, the epitaxial layer 12 may be a semiconductor containing more than one element, and these elements may be a combination selected from Ga, In, N, Al, Ge, As, P, and Se. This embodiment does not limit it here.

Specifically, the conductivity types of the first-type semiconductor layer 121 and the second-type semiconductor layer 122 are different. For example, the first-type semiconductor layer 121 is an N-type semiconductor layer, and the second-type semiconductor layer 122 is a P-type semiconductor layer.

Taking the first-type semiconductor layer 121 as an N-type semiconductor layer and the second-type semiconductor layer 122 as a P-type semiconductor layer as an example, the epitaxial layer 12 sequentially includes the N-type semiconductor layer 121 and the surface covering part of the N-type semiconductor layer 121 from bottom to top. The P-type semiconductor layer 122, that is, the surfaces of the N-type semiconductor layer and the P-type semiconductor layer have a stepped structure. There are many ways to prepare this stepped structure. For example, the N-type semiconductor layer and the P-type semiconductor layer can be successively formed on the substrate. The P-type semiconductor layer, and then etching a part of the P-type semiconductor layer until the surface of the N-type semiconductor layer is exposed to form a ladder structure. It can be understood that there are many techniques for preparing the epitaxial layer 12 , which will not be described in detail here.

Furthermore, the insulating reflective layer 14 can protect the structure of the LED device, and can further improve the luminous efficiency of the LED device by reflecting the light emitted by the LED to the substrate. Optionally, the structure of the insulating reflective layer may be a single-layer structure or a multi-layer structure.

Optionally, the insulating reflection layer 14 may be a multi-layer structure, such as a distributed Bragg reflector (distributed bragg reflector, DBR for short) or an omni-directional reflector (Omni-Directional Reflector, ODR for short).

Among them, the DBR is composed of two materials with different refractive indices arranged alternately, and the optical thickness of each layer of material is 1/4 of the central reflection wavelength, so it is a quarter-wavelength multilayer system. The reflectivity of the Bragg reflector is very high, up to 99%, so it can effectively improve the brightness of the LED device, and the insulating reflective layer with a structure of DBR can avoid the light absorption problem of the metal reflective layer, and can also be changed by changing the material Refractive index or thickness to adjust the energy gap position. Further, the DBR can be prepared from any two materials of TiO2, SiO2, Al2O3, Ta2O5, Si3N4, ZnS, and CaF2. Specifically, the method for preparing the DBR can be a common DBR preparation method, which will not be described in detail here.

Wherein, the ODR may be composed of at least one metal layer and at least one insulating layer, and the metal layer covers the insulating layer and is located above the insulating layer to avoid direct contact with the semiconductor. Further, the metal layer can be made of any material in Au, Ag, Al, Cu, Pd, Rh, Cr, Ti, and the insulating layer can be made of any material in TiO2, SiO2, Al2O3, Ta2O5, Si3N4, ZnS, CaF2 Prepare to form. Specifically, the method for preparing the ODR may adopt a common ODR preparation method, which will not be described in detail here.

Optionally, the insulating reflective layer 14 may have a single-layer structure, and further, the insulating reflective layer may include a mixture of silica gel and titanium oxide. The insulating reflective layer with a single-layer structure can effectively simplify the structure of the device and save the process.

Among them, the transparent conductive layer (Transparent Conductive Layer, referred to as TCL) formed between the second-type semiconductor layer and the insulating reflective layer has high electrical conductivity and good light transmission characteristics, high mechanical hardness, and good chemical stability. , and can achieve the effect of spreading current and reducing contact resistance. Further, the transparent conductive layer may include but not limited to any one of NiAu, ITO, and ZnO.

Specifically, the first electrode is formed on the surface of the first type semiconductor layer and is electrically connected to the first type semiconductor layer, the second electrode is formed on the surface of the second type semiconductor layer and is electrically connected to the second type semiconductor layer, and the first electrode and The second electrodes are separated, and the insulating reflective layer covering the surface of the epitaxial layer separates the first electrodes from the second electrodes. Further, the materials of the first electrode and the second electrode may be Ti, Cr, gold, silver, aluminum, platinum or molybdenum, etc., and the selection of specific materials may be determined according to actual conditions. Preferably, the first electrode and the second electrode can be formed together in the same process link by evaporation, sputtering, printing process or electroplating process, so as to simplify the process flow. In practical application, the first electrode and the second electrode may be strip electrodes parallel to the first direction.

In the LED device provided in this embodiment, the surfaces of the first-type semiconductor layer and the second-type semiconductor layer have a stepped structure, and the surfaces of the first-type semiconductor layer and the second-type semiconductor layer are respectively provided with a first electrode and a second electrode, and the insulating reflection The epitaxial layer covers the exposed surface of the epitaxial layer, and the transparent conductive layer is arranged between the second-type semiconductor layer and the insulating reflection layer, which effectively simplifies the structure and preparation process of the LED device, and improves the production yield.

FIG. 2A is a schematic cross-sectional structure diagram of an LED device provided by Embodiment 2 of the present invention. As shown in FIG. 2A, the device includes:

A substrate 21, an epitaxial layer 22, a transparent conductive layer 23, an insulating reflective layer 24, and a first electrode 25 and a second electrode 26; wherein,

The epitaxial layer 22 includes an N-type semiconductor layer 221 on the substrate 21 and a P-type semiconductor layer 222 on the surface of a part of the N-type semiconductor layer 221;

The first electrode 25 is located on the partial area surface of the N-type semiconductor layer 221, and the second electrode 26 is located on the partial area surface of the P-type semiconductor layer 222; the insulating reflective layer 24 covers the surface of the epitaxial layer 22; the transparent conductive layer 23 is located on the P-type semiconductor layer 222. Between the semiconductor layer 222 and the insulating reflective layer 24 , the transparent conductive layer 23 includes a plurality of transparent conductive units 231 arranged separately.

Wherein, the substrate 21 may specifically be a transparent substrate to realize the luminous effect of the LED device. Optionally, the substrate 21 may include but not limited to any one of sapphire, SiC, GaN, and AlN. The epitaxial layer 22 can be a semiconductor element, such as single crystal silicon, polycrystalline silicon or silicon with an amorphous structure, or a mixed semiconductor structure, such as silicon carbide, indium antimonide, lead telluride, indium arsenide, indium phosphide, arsenic Gallium or gallium antimonide or silicon germanium (SiGe), alloy semiconductors or combinations thereof. In addition, the epitaxial layer 12 may be a semiconductor containing more than one element, and these elements may be a combination selected from Ga, In, N, Al, Ge, As, P, and Se. This embodiment does not limit it here.

Specifically, the epitaxial layer 22 sequentially includes an N-type semiconductor layer 221 and a P-type semiconductor layer 222 covering part of the surface of the N-type semiconductor layer 221 from bottom to top, that is, the surfaces of the N-type semiconductor layer and the P-type semiconductor layer have a stepped structure. There are many methods for this stepped structure. For example, an N-type semiconductor layer and a P-type semiconductor layer can be sequentially stacked on the substrate to form an N-type semiconductor layer, and then a part of the P-type semiconductor layer is etched until the N-type semiconductor layer is exposed. The surface of the layer forms a ladder structure. It can be understood that there are many techniques for preparing the epitaxial layer 22 , which will not be described in detail here.

Furthermore, the insulating reflective layer 24 can protect the structure of the LED device, and can further improve the luminous efficiency of the LED device by reflecting the light emitted by the LED to the substrate. Optionally, the structure of the insulating reflective layer may be a single-layer structure or a multi-layer structure.

Optionally, the insulating reflection layer may be a multilayer structure, such as a distributed Bragg reflector (distributed bragg reflector, DBR for short) or an omni-directional reflector (Omni-Directional Reflector, ODR for short).

Among them, the DBR is composed of two materials with different refractive indices arranged alternately, and the optical thickness of each layer of material is 1/4 of the central reflection wavelength, so it is a quarter-wavelength multilayer system. The reflectivity of the Bragg reflector is very high, up to 99%, so it can effectively improve the brightness of the LED device, and the insulating reflective layer with a structure of DBR can avoid the light absorption problem of the metal reflective layer, and can also be changed by changing the material Refractive index or thickness to adjust the energy gap position. Further, the DBR can be prepared from any two materials of TiO2, SiO2, Al2O3, Ta2O5, Si3N4, ZnS, and CaF2. Specifically, the method for preparing the DBR can be a common DBR preparation method, which will not be described in detail here.

Wherein, the ODR may be composed of at least one metal layer and at least one insulating layer, and the metal layer covers the insulating layer and is located above the insulating layer to avoid direct contact with the semiconductor. Further, the metal layer material can be prepared from any material in Au, Ag, Al, Cu, Pd, Rh, Cr, Ti, and the insulating layer can be made of any material in TiO2, SiO2, Al2O3, Ta2O5, Si3N4, ZnS, CaF2 Material preparation forms. Specifically, the method for preparing the ODR may adopt a common ODR preparation method, which will not be described in detail here.

Optionally, the insulating reflective layer may have a single-layer structure, and further, the insulating reflective layer may include a mixture of silica gel and titanium oxide. The insulating reflective layer with a single-layer structure can effectively simplify the structure of the device and save the process.

Specifically, the first electrode is formed on the surface of the N-type semiconductor layer and is electrically connected to the N-type semiconductor layer; the second electrode is formed on the surface of the P-type semiconductor layer and is electrically connected to the P-type semiconductor layer, and the first electrode and the second electrode are separated It is provided that the insulating reflective layer covering the surface of the epitaxial layer isolates the first electrode from the second electrode. Further, the material of the first electrode and the second electrode may be gold, silver, aluminum, platinum or molybdenum, etc., and the selection of specific materials may be determined according to actual conditions. Preferably, the first electrode and the second electrode can be formed together in the same process link by evaporation, sputtering, printing process or electroplating process, so as to simplify the process flow.

Wherein, the transparent conductive layer (Transparent Conductive Layer, referred to as TCL) formed between the P-type semiconductor layer and the insulating reflective layer has high electrical conductivity and good light transmission characteristics, high mechanical hardness, and good chemical stability. And it can achieve the effect of spreading current and reducing contact resistance. Further, the transparent conductive layer may include but not limited to any one of NiAu, ITO, and ZnO.

Preferably, in order to reduce the influence of the transparent conductive layer on the light emission of the LED device, so that more light can be reflected to the substrate through the insulating reflective layer, the transparent conductive layer 23 may include a plurality of transparent conductive units 231 arranged separately, so that more The light is directly irradiated on the insulating reflective layer through the gaps between the transparent conductive units 231 to reflect and reach the substrate, so that the luminous efficiency of the LED device can be further improved on the basis of realizing diffusion current and reducing contact resistance.

The transparent conductive layer 23 in this embodiment includes a plurality of separate transparent conductive units 231 , and the transparent conductive units 231 are independent of each other, without direct contact, but indirectly connected and conducted through the second electrode. For example, FIG. 2B is a schematic top view of the transparent conductive layer in Embodiment 2 of the present invention. As shown in FIG. 2B , the transparent conductive layer 23 includes a plurality of separate transparent conductive units 231, and the transparent conductive units 231 are not directly connected to each other. touch. It should be noted that what is shown in the figure is only an exemplary embodiment, and does not limit the specific parameters of the transparent conductive layer 23 . For example, the arrangement and shape of the transparent conductive units 231 can be set according to the size and structure of the device.

In the LED device provided in this embodiment, the surfaces of the N-type semiconductor layer and the P-type semiconductor layer have a stepped structure, the surfaces of the N-type semiconductor layer and the P-type semiconductor layer are respectively provided with a first electrode and a second electrode, and the insulating reflective layer covers the exposed On the surface of the epitaxial layer, a transparent conductive layer is arranged between the P-type semiconductor layer and the insulating reflection layer, which effectively simplifies the structure and manufacturing process of the LED device, and improves the production yield. And the transparent conductive layer includes a plurality of transparent conductive units separately arranged, so that more light is directly irradiated on the insulating reflective layer to reflect and reach the substrate, so as to realize the diffusion current and reduce the contact resistance, and further improve the LED performance. Luminous efficiency of the device.

Fig. 3A is a schematic cross-sectional structure diagram of an LED device provided by Embodiment 3 of the present invention. As shown in Fig. 3A, the device includes:

A substrate 31, an epitaxial layer 32, a transparent conductive layer 33, an insulating reflective layer 34, and a first electrode 35 and a second electrode 36; wherein,

The epitaxial layer 32 includes an N-type semiconductor layer 321 on the substrate 31 and a P-type semiconductor layer 322 on the surface of a part of the N-type semiconductor layer 321;

The first electrode 35 is located on the partial area surface of the N-type semiconductor layer 321, and the second electrode 36 is located on the partial area surface of the P-type semiconductor layer 322; the insulating reflective layer 34 covers the surface of the epitaxial layer 32; the transparent conductive layer 33 is located on the P-type semiconductor layer. Between the semiconductor layer 322 and the insulating reflective layer 34, the transparent conductive layer 33 is provided with openings 331, and the opening ratio is not greater than 90%.

Wherein, the porosity ratio can be calculated by the following formula: porosity ratio=(1-area of the transparent conductive layer/area of the P-type semiconductor layer)×100%. The area of the transparent conductive layer mentioned here refers to the actual area of the transparent conductive layer, that is, the area of the transparent conductive layer excluding openings.

Wherein, the substrate may specifically be a transparent substrate, so as to realize the light emitting effect of the LED device. Optionally, the substrate may include but not limited to any one of sapphire, SiC, GaN, and AlN. The epitaxial layer can be a semiconductor element, such as monocrystalline silicon, polycrystalline silicon or silicon with an amorphous structure, or a mixed semiconductor structure, such as silicon carbide, indium antimonide, lead telluride, indium arsenide, indium phosphide, arsenide Gallium or gallium antimonide or silicon germanium (SiGe), alloy semiconductors or combinations thereof. In addition, the epitaxial layer 12 may be a semiconductor containing more than one element, and these elements may be a combination selected from Ga, In, N, Al, Ge, As, P, and Se. This embodiment does not limit it here.

Specifically, the epitaxial layer includes an N-type semiconductor layer and a P-type semiconductor layer covering part of the surface of the N-type semiconductor layer from bottom to top, that is, the surfaces of the N-type semiconductor layer and the P-type semiconductor layer have a ladder structure, and the ladder structure is prepared. There are many ways to do this. For example, an N-type semiconductor layer and a P-type semiconductor layer can be sequentially formed on the substrate, and then a part of the P-type semiconductor layer is etched until the surface of the N-type semiconductor layer is exposed. form a ladder structure. It can be understood that there are many techniques for preparing the epitaxial layer 22 , which will not be described in detail here.

Furthermore, the insulating reflective layer can protect the structure of the LED device, and can further improve the luminous efficiency of the LED device by reflecting the light emitted by the LED to the substrate. Optionally, the structure of the insulating reflective layer may be a single-layer structure or a multi-layer structure.

Optionally, the insulating reflection layer may be a multilayer structure, such as a distributed Bragg reflector (distributed bragg reflector, DBR for short) or an omni-directional reflector (Omni-Directional Reflector, ODR for short).

Among them, the DBR is composed of two materials with different refractive indices arranged alternately, and the optical thickness of each layer of material is 1/4 of the central reflection wavelength, so it is a quarter-wavelength multilayer system. The reflectivity of the Bragg reflector is very high, up to 99%, so it can effectively improve the brightness of the LED device, and the insulating reflective layer with a structure of DBR can avoid the light absorption problem of the metal reflective layer, and can also be changed by changing the material Refractive index or thickness to adjust the energy gap position. Further, the DBR can be prepared from any two materials of TiO2, SiO2, Al2O3, Ta2O5, Si3N4, ZnS, and CaF2. Specifically, the method for preparing the DBR can be a common DBR preparation method, which will not be described in detail here.

Wherein, the ODR may be composed of at least one metal layer and at least one insulating layer, and the metal layer covers the insulating layer and is located above the insulating layer to avoid direct contact with the semiconductor. Further, the metal layer material can be prepared from any material in Au, Ag, Al, Cu, Pd, Rh, Cr, Ti, and the insulating layer can be made of any material in TiO2, SiO2, Al2O3, Ta2O5, Si3N4, ZnS, CaF2 Material preparation forms. Specifically, the method for preparing the ODR may adopt a common ODR preparation method, which will not be described in detail here.

Optionally, the insulating reflective layer may have a single-layer structure, and further, the insulating reflective layer may include a mixture of silica gel and titanium oxide. The insulating reflective layer with a single-layer structure can effectively simplify the structure of the device and save the process.

Specifically, the first electrode is formed on the surface of the N-type semiconductor layer and is electrically connected to the N-type semiconductor layer; the second electrode is formed on the surface of the P-type semiconductor layer and is electrically connected to the P-type semiconductor layer, and the first electrode and the second electrode are separated It is provided that the insulating reflective layer covering the surface of the epitaxial layer isolates the first electrode from the second electrode. Further, the materials of the first electrode and the second electrode may be Ti, Cr, gold, silver, aluminum, platinum or molybdenum, etc., and the selection of specific materials may be determined according to actual conditions. Preferably, the first electrode and the second electrode can be formed together in the same process link by evaporation, sputtering, printing process or electroplating process, so as to simplify the process flow. In practical application, the first electrode and the second electrode may be strip electrodes parallel to the first direction.

Wherein, the transparent conductive layer (Transparent Conductive Layer, referred to as TCL) formed between the P-type semiconductor layer and the insulating reflective layer has high electrical conductivity and good light transmission characteristics, high mechanical hardness, and good chemical stability. And it can achieve the effect of spreading current and reducing contact resistance. Further, the transparent conductive layer may include but not limited to any one of NiAu, ITO, and ZnO.

In this embodiment, in order to reduce the influence of the transparent conductive layer on the light emission of the LED device, so that more light can be reflected to the substrate through the insulating reflective layer, the transparent conductive layer is provided with openings, so that more light can pass through the openings Direct irradiation is reflected on the insulating reflective layer and reaches the substrate, so that the luminous efficiency of the LED device can be further improved on the basis of realizing the diffusion current and reducing the contact resistance. Specifically, the open porosity of the transparent conductive layer is not greater than 90%, so as to ensure diffusion current and reduce contact resistance. Preferably, the openings 331 can be uniformly distributed, so that the light emitted by the LED device is more uniform, and the luminous effect is optimized.

The transparent conductive layer 33 in this embodiment is a continuous conductive film with openings 331 opened therein. For example, FIG. 3B is a schematic top view of the transparent conductive layer in the third embodiment of the present invention. As shown in FIG. 3B , the transparent conductive layer 33 is a continuous conductive film with openings 331 thereon. It should be noted that what is shown in the figure is only an exemplary embodiment, and does not limit the specific parameters of the opening 331 . For example, the arrangement and shape of the openings can be set according to the size and structure of the device.

In the LED device provided in this embodiment, the surfaces of the N-type semiconductor layer and the P-type semiconductor layer have a stepped structure, the surfaces of the N-type semiconductor layer and the P-type semiconductor layer are respectively provided with a first electrode and a second electrode, and the insulating reflective layer covers the exposed On the surface of the epitaxial layer, a transparent conductive layer is arranged between the P-type semiconductor layer and the insulating reflection layer, which effectively simplifies the structure and manufacturing process of the LED device, and improves the production yield. And the transparent conductive layer has openings, so that more light can be directly irradiated on the insulating reflective layer to reflect and reach the substrate, so as to realize the diffusion current and reduce the contact resistance, and further improve the luminous efficiency of the LED device.

Optionally, in order to improve the reliability of the electrical connection between the electrode and the outside world, the electrical contact area of the electrode can be increased. Correspondingly, FIG. 4A is a schematic cross-sectional structure diagram of the LED device provided by Embodiment 4 of the present invention, as shown in FIG. 4A , On the basis of the LED device described in any one of Embodiments 1 to 3 having a substrate, an epitaxial layer, a transparent conductive layer, and a first electrode and a second electrode, the LED device further includes:

The first metal layer 41 and the second metal layer 42 arranged separately;

The first metal layer 41 covers the first electrode and part of the insulating reflective layer; the second metal layer 42 covers the second electrode and part of the insulating reflective layer.

Specifically, FIG. 4B is a schematic top view of the structure of FIG. 4A. Wherein, the first metal layer 41 and the second metal layer 42 can be Ti, Cr, gold, silver, aluminum, platinum or molybdenum, etc., and the selection of specific materials can be determined according to the actual situation. Preferably, the first metal layer 41 , the second metal layer 42 , the first electrode and the second electrode can be jointly formed in the same process by evaporation, sputtering, printing process or electroplating process, so as to simplify the process flow.

The LED device provided by this embodiment can increase the electrical contact area between the device and the outside world and improve the reliability of the device by providing the first metal layer connected to the first electrode and the second metal layer connected to the second electrode.

Fig. 5A is a schematic top view structure diagram of an LED device provided by Embodiment 5 of the present invention. On the basis of the LED device described in any one of the three embodiments,

At least one first metal strip 51 extends from the first electrode toward the second electrode; at least one second metal strip 52 extends from the second electrode toward the first electrode; the first metal strips 51 and the second metal strips 52 are alternately arranged.

In practical application, the LED device can be packaged by flip-chip technology.

Specifically, the first metal strip 51 and the second metal strip 52 are parallel. In order to save occupied area, the first electrode and the second electrode are perpendicular to the first metal strip 51 and the second metal strip 52 .

Wherein, the first metal strip 51 and the second metal strip 52 can be Ti, Cr, gold, silver, aluminum, platinum or molybdenum, etc., and the selection of specific materials can be determined according to the actual situation. Preferably, the first metal strip 51 , the second metal strip 52 , the first electrode and the second electrode can be jointly formed in the same process by evaporation, sputtering, printing process or electroplating process, so as to simplify the process flow. The first metal strip 51 and the second metal strip 52 can help current spread, thereby improving the luminous efficiency of the LED device.

In order to improve the stability and reliability of the LED device, as shown in Figure 5B, Figure 5B is a schematic top view of another LED device provided in Embodiment 5 of the present invention. On the basis of the implementation shown in Figure 5A, the insulating reflection The layer covers the first metal strip 51 and the second metal strip 52 and covers a partial area of the first electrode and the second electrode. For example, the insulating reflective layer may cover the first electrode and the second electrode except the two ends thereof.

In the above embodiments, the first metal strip and the second metal strip, and part of the first electrode and the second electrode are covered with an insulating reflective layer, which can protect the electrodes and improve the reliability and stability of the device.

As shown in FIG. 5C, FIG. 5C is a schematic top view structure diagram of another LED device provided by Embodiment 5 of the present invention. On the basis of the embodiment shown in FIG. 5B, the LED device further includes: a third metal layer 53 arranged separately and a fourth metal layer 54;

The third metal layer 53 covers the area of the first electrode not covered by the insulating reflective layer and part of the insulating reflective layer; the fourth metal layer 54 covers the area of the second electrode not covered by the insulating reflective layer and part of the insulating reflective layer.

In the above embodiment, by setting the first metal layer electrically connected to the first electrode, and the second metal layer connected to the second electrode, the electrical connection contact area between the LED device and the outside world is increased, and the electrical connection characteristics and characteristics of the device are improved. reliability.

In the LED device provided in this embodiment, the surfaces of the first-type semiconductor layer and the second-type semiconductor layer have a stepped structure, and the surfaces of the first-type semiconductor layer and the second-type semiconductor layer are respectively provided with a first electrode and a second electrode, and are insulated. The reflective layer covers the exposed surface of the epitaxial layer, the transparent conductive layer is arranged between the second-type semiconductor layer and the insulating reflective layer, and the first electrode and the second electrode are extended with alternately arranged metal strips, thereby effectively simplifying the LED The structure and preparation process of the device can improve the production yield and help the current spread, thereby improving the luminous efficiency of the LED device.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (10)

1. A LED device, characterized in that it comprises: a substrate, an epitaxial layer, a transparent conductive layer, an insulating reflective layer, and a first electrode and a second electrode; wherein, The epitaxial layer includes a first-type semiconductor layer on the substrate and a second-type semiconductor layer on the surface of a partial region of the first-type semiconductor layer; The first electrode is located on the surface of a partial area of the first-type semiconductor layer, the second electrode is located on the surface of a partial area of the second-type semiconductor layer; the insulating reflective layer covers the surface of the epitaxial layer ; The transparent conductive layer is located between the second type semiconductor layer and the insulating reflective layer. 2. The LED device according to claim 1, wherein the transparent conductive layer comprises a plurality of transparent conductive units arranged separately. 3. The LED device according to claim 1, wherein the transparent conductive layer is provided with openings, and the opening ratio is not greater than 90%. 4. The LED device according to any one of claims 1-3, wherein the transparent conductive layer comprises any one of NiAu, ITO, ZnO, AZO and TiN. 5. The LED device according to any one of claims 1-3, wherein the substrate comprises any one of sapphire, SiC, GaN, and AlN. 6. The LED device according to any one of claims 1-3, wherein the insulating reflection layer is a distributed Bragg reflector (DBR) or an omni-angle reflector (ODR). 7. The LED device according to claim 6, wherein the DBR comprises any two of TiO2, SiO2, Al2O3, Ta2O5, Si3N4, ZnS, and CaF2. 8. The LED device according to claim 6, wherein the ODR comprises an insulating layer and a metal layer covering the insulating layer, the metal layer comprising Au, Ag, Al, Cu, Pd, Rh, Cr , At least one of Ti. 9. The LED device according to any one of claims 1-3, wherein the insulating reflective layer is a mixture of silica gel and titanium oxide. 10. The LED device according to any one of claims 1-3, further comprising: a first metal layer and a second metal layer separately arranged; The first metal layer covers the first electrode and part of the insulating reflective layer; the second metal layer covers the second electrode and part of the insulating reflective layer.