Light emitting diode structure and manufacturing method thereof

Abstract

The invention provides a light emitting diode structure. The light emitting diode structure comprises a first electrode layer, a first ohmic contact layer, a first coarsening layer, a first limiting layer, an MQW active layer, a second limiting layer, a second coarsening layer, a DBR reflector layer, a second ohmic contact window layer, a holophote structure layer, a conductive substrate and a second electrode. Wherein the DBR reflecting mirror layer and the second ohmic contact window layer comprise hole opening parts, and the hole opening parts are aligned with the position of a first electrode of the first electrode layer; and the second coarsening layer is provided with a second coarsening area on a part corresponding to the opening part of the DBR reflecting mirror layer. According to the invention, the DBR reflector layer is epitaxially grown in the LED chip structure, and the light extraction efficiency and the light-emitting brightness of the light-emitting diode can be effectively improved by patterning the DBR reflector layer and the local coarsening structure and combining the chip total reflection mirror structure, so that the manufacturing process flow of the chip is simplified.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor optoelectronic chips, and in particular to a light emitting diode structure and a manufacturing method thereof. Background Art

[0002] Light-emitting diodes are widely used in various display and lighting fields due to their small size, low power consumption, long life, and high brightness, such as micro-pitch display screens, smart car lights, landscape lighting, medical equipment, etc. In light-emitting diodes, the light emitted by the active area is emitted in all directions. In order to increase the light extraction efficiency of the LED light-emitting surface, it is usually considered to deposit a DBR reflector layer in the chip structure for the second time to reflect the light emitted by the active layer toward the light-emitting surface, thereby improving the brightness of the chip. However, the secondary deposition of the DBR layer increases the chip manufacturing process, the process is complicated, and the quality and reflection efficiency of the secondary deposited DBR reflector layer are low.

[0003] In addition, since the DBR reflector layer only has a strong reflective effect on incident light that is perpendicular to it or at a small angle to the vertical direction, and the reflectivity of light incident at a large angle is very low, the light extraction efficiency of the LED is greatly limited. At the same time, for the DBR corresponding to the vertical direction of the electrode, there are the following problems: 1) Light incident at a large angle to the above area is not reflected by the DBR reflector layer; 2) Light radiated to the DBR reflector layer near the vertical direction is repeatedly reflected between the electrode and the DBR reflector layer, and the electrode itself has an absorption effect on light, resulting in the final conversion into heat. This part of the light is not extracted, affecting the light extraction efficiency of the entire LED device structure.

[0004] Therefore, how to improve the external quantum efficiency and chip brightness of light-emitting diodes, simplify the chip manufacturing process, and reduce chip processing costs is an urgent problem to be solved. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a light emitting diode structure and a method for preparing the same, so as to further improve the external quantum efficiency and chip brightness of the light emitting diode, while simplifying the chip manufacturing process and reducing the chip processing cost.

[0006] A first aspect of the present application provides a light emitting diode structure, which comprises, in order from the light emitting surface side:

[0007] A first electrode layer, a first ohmic contact layer, a first roughening layer, a first confinement layer, an MQW active layer, a second confinement layer, a second roughening layer, a DBR reflector layer, a second ohmic contact window layer, a total reflector structure layer, a conductive substrate, and a second electrode;

[0008] Wherein, the first electrode layer and the first ohmic contact layer have the same first patterned structure;

[0009] The DBR reflector layer and the second ohmic contact window layer have the same second patterned structure, the second patterned structure includes an opening portion, and the opening portion is aligned with the position of the first electrode of the first electrode layer;

[0010] The second roughened layer is provided with a second roughened region at a portion corresponding to the opening of the DBR reflector layer.

[0011] According to some embodiments of the present application, the total reflector structure layer is a metal reflector layer, and the metal reflector layer is adjacent to the second ohmic contact window layer and extends into the openings of the DBR reflector layer and the second ohmic contact window layer.

[0012] According to some embodiments of the present application, the total reflector structure layer includes an insulating dielectric layer and a metal reflector layer, the insulating dielectric layer is adjacent to the second ohmic contact window layer and extends into the openings of the DBR reflector layer and the second ohmic contact window layer;

[0013] The insulating dielectric layer is provided with a conductive hole, and the metal reflector layer is in electrical contact with the second ohmic contact window layer through the conductive hole in the insulating dielectric layer;

[0014] The metal reflector layer, the insulating dielectric layer and the second ohmic contact window layer constitute an ODR total reflector structure.

[0015] According to some embodiments of the present application, the first roughened layer is provided with a first roughened region on a portion where the first electrode is not provided.

[0016] According to some embodiments of the present application, a roughening layer is provided on the side of the opening portion of the DBR reflector layer.

[0017] According to some embodiments of the present application, the area of ​​the second roughened region is greater than or equal to the area of ​​the first electrode.

[0018] Another aspect of the present application provides a method for manufacturing a light emitting diode structure, comprising:

[0019] Preparation of light-emitting diode epitaxial wafer: epitaxially growing a buffer layer, a barrier layer, a first ohmic contact layer, a first roughening layer, a first confinement layer, an MQW active layer, a second confinement layer, a second roughening layer, a DBR reflector layer and a second ohmic contact window layer on a temporary substrate in sequence to form a light-emitting diode epitaxial wafer;

[0020] Patterning the DBR reflector layer and the second ohmic contact window layer to form corresponding openings in the DBR reflector layer and the second ohmic contact window layer;

[0021] Roughening the second roughening layer in the area where the opening of the DBR reflector layer is located or roughening the side surfaces of the second roughening layer and the opening of the DBR reflector layer at the same time;

[0022] Manufacturing a total reflection mirror structure layer on the second ohmic contact window layer of the light emitting diode epitaxial wafer;

[0023] Fabricating a permanent conductive substrate and a second electrode on the total reflection mirror structure layer;

[0024] removing the temporary substrate, the buffer layer and the barrier layer, and forming a first electrode layer on the exposed first ohmic contact layer;

[0025] The first electrode layer and the first ohmic contact layer are patterned to obtain a patterned first electrode and a first electrode ohmic contact layer, so that the positions of the first electrode and the first electrode ohmic contact layer correspond to the positions of the openings of the DBR reflector layer.

[0026] According to some embodiments of the present application, manufacturing a total reflection mirror structure layer on a second ohmic contact window layer of a light emitting diode epitaxial wafer includes:

[0027] A metal reflector layer is formed on the second ohmic contact window layer of the light emitting diode epitaxial wafer. The metal reflector layer is adjacent to the second ohmic contact window layer and extends into the openings of the DBR reflector layer and the second ohmic contact window layer.

[0028] According to some embodiments of the present application, manufacturing a total reflection mirror structure layer on a second ohmic contact window layer of a light emitting diode epitaxial wafer includes:

[0029] Forming an insulating dielectric layer on the second ohmic contact window layer of the light-emitting diode epitaxial wafer, wherein the insulating dielectric layer is adjacent to the second ohmic contact window layer and extends into the DBR reflector layer and the opening portion of the second ohmic contact window layer;

[0030] Patterning the insulating dielectric layer to form conductive holes therein;

[0031] A metal reflector layer is deposited on an insulating dielectric layer having conductive holes, so that the metal reflector layer is in electrical contact with the second ohmic contact window layer through the conductive holes in the insulating dielectric layer. The metal layer, the insulating dielectric layer and the second ohmic contact window layer constitute an ODR total reflector structure.

[0032] According to some embodiments of the present application, the method for manufacturing the light emitting diode structure further includes:

[0033] A roughening process is performed on a portion of the first roughened layer where the first electrode and the first ohmic contact layer are not provided, thereby forming a first roughened region.

[0034] In the light-emitting diode structure and the manufacturing method thereof of the present application, the light-emitting surface electrode corresponds to the local roughened area in the second roughened layer, and the light in the vertical direction of the electrode can be scattered by the corresponding roughened area, and is emitted from the device in a direction at a certain angle to the vertical direction, and is converted into effective output light, thereby solving the problem that the output light in the vertical direction of the electrode cannot be effectively utilized, and improving the light extraction efficiency of the LED.

[0035] At the same time, the present application adopts the setting of a DBR reflector layer combined with a total reflector structure layer. The setting of the total reflector makes up for the defect of the DBR reflector layer's low reflectivity for large-angle light, and can reflect its unreflected light to the light-emitting end of the device, further improving the LED light extraction efficiency.

[0036] The present application grows a DBR reflector layer during the growth process of the epitaxial structure layer. The grown DBR reflector layer has high quality and high reflection efficiency, and there is no need to add a secondary deposition process, which simplifies the chip preparation process and reduces the chip production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a schematic diagram of a light emitting diode structure according to an embodiment of the present application;

[0038] Figure 1a-1g yes Figure 1 A schematic diagram of the structure of the light emitting diode during the preparation process;

[0039] Figure 2 is a schematic diagram of a light emitting diode structure according to another embodiment of the present application;

[0040] Figure 2a yes Figure 2 A structural schematic diagram of the preparation process of the light-emitting diode structure. DETAILED DESCRIPTION

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the exemplary embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the accompanying drawings, components with the same or similar functions are indicated by the same or similar reference numerals. In addition, some components that are not directly related to the concept of the present invention may be omitted from the illustration. The description of the drawings and specific embodiments is only for a better understanding of the present invention, and the present invention is not limited to the embodiments illustrated in the drawings and described in the specification.

[0042] The technical terms or scientific terms used in the present invention should be the common meanings understood by people with ordinary skills in the field to which the present invention belongs. The use of "including" or "comprising" and similar words in the present invention indicates an open meaning, and does not exclude other elements, components, parts or items except for the elements, parts, parts or items clearly listed. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. "First", "second" and the like are used to distinguish different components and do not indicate a specific order.

[0043] like Figure 1 As shown, the light-emitting diode structure of the present application includes, from the light-emitting surface to the substrate side, a first electrode layer 301 composed of a patterned first electrode 3011, a first ohmic contact layer 103 composed of a patterned first electrode ohmic contact layer 1031, a first roughening layer 104, a first confinement layer 105, an MQW active layer 106, a second confinement layer 107, a second roughening layer 108, a DBR reflector layer 109, a second ohmic contact window layer 110, a metal reflector layer 201, a conductive substrate 200, and a second electrode 202. The first electrode layer 301 and the first ohmic contact layer 103 have the same patterned structure, that is, the first electrode 3011 and the first electrode ohmic contact layer 1031 correspond in position. The second electrode 202 is a full-surface electrode. The second electrode has opposite polarity to the first electrode.

[0044] In some embodiments, a first roughened region 1041 is provided on a portion of the first roughened layer 104 where the first electrode 3011 and the first electrode ohmic contact layer 1031 are not provided. The first roughened region 1041 can be micro-etched and roughened using a wet solution to form a concave-convex structure. The solution used can be any one of HCL, H3PO5, CH3COOH, HF, HNO3, H2O2, or a mixed solution of two or more. Optionally, dry etching or other methods can also be used to roughen the roughened region. The concave-convex structure of the first roughened region 1041 can scatter the light directed toward the light emitting surface, preventing the light directed toward the light emitting surface from being reflected back into the LED, thereby reducing the LED light extraction efficiency and external quantum efficiency.

[0045] like Figure 1 As shown, the DBR reflector layer 109 and the second ohmic contact window layer 110 have the same patterned structure, and correspond to the patterned structures of the first electrode layer 301 and the first ohmic contact layer 103. The patterned structure of the DBR reflector layer 109 and the second ohmic contact window layer 110 includes an opening portion 1092 and an opening portion 1102 aligned (see Figure 1b ), the openings 1092 and 1102 are aligned with the positions of the first electrode 3011. The second roughening layer 108 is provided with a second roughening region 1081 on the portion corresponding to the opening of the DBR reflector layer 109. The area of ​​the second roughening region 1081 is preferably greater than or equal to the area of ​​the first electrode 3011. The second roughening region can be micro-etched and roughened using a wet solution to form a concave-convex structure, and the solution used can be any one of HCL, H3PO5, CH3COOH, HF, HNO3, H2O2, or a mixed solution of two or more thereof.

[0046] The function of the concave-convex structure of the second roughened area 1081 is to change the direction of the light R1 (the light perpendicular to the LED stacking direction directly below the electrode) emitted toward the DBR layer in the direction perpendicular to the electrode through diffuse reflection, and then emit it toward the light emitting surface in a direction at a certain angle to the vertical direction, and finally emit it from the device, thereby preventing the light in the perpendicular direction of the electrode from being consumed by reflecting back and forth between the DBR reflector layer and the first electrode and being unable to be effectively utilized, thereby improving the light extraction efficiency of the LED, and then improving the external quantum efficiency and brightness of the LED.

[0047] exist Figure 1 In the illustrated embodiment, the metal reflector layer 201 is disposed on the side of the DBR reflector layer 109 facing away from the light emitting surface; specifically, the metal reflector layer 201 is adjacent to the second ohmic contact window layer 110 and extends into the openings of the DBR reflector layer 109 and the second ohmic contact window layer 110. The portion of the metal reflector layer 201 extending into the openings of the DBR reflector layer 109 and the second ohmic contact window layer 110 is adjacent to the second roughened region 1081 of the second roughened layer 108, and has a roughened concave-convex interface complementary to the concave-convex structure of the second roughened region 1081. The provision of the metal reflector layer 201 makes up for the defect of the low reflectivity of the DBR reflector layer 108 for large-angle light, and can reflect the unreflected light R2 to the light emitting end of the device, further improving the light extraction efficiency and external quantum efficiency of the LED. Preferably, the side of the opening 1092 of the DBR reflector layer 109 is provided with a roughened layer 1091. The roughening layer 1091 scatters the light directed to the opening of the DBR reflector layer, thereby further improving the light extraction efficiency. Similarly, the roughening layer 1091 can be roughened by micro-etching using a wet solution, and the solution used is preferably any one of HCL, H3PO5, CH3COOH, HF, HNO3, H2O2, or a mixed solution of two or more. Preferably, the roughening of the roughening layer 1091 can be completed in one micro-etching process together with the local roughening of the second roughening layer 108.

[0048] In some embodiments, the light emitting diode structure can be a reverse polarity red light emitting diode, wherein the first electrode 1031 is an n-electrode, which can be various metals such as Au, Ni, Cu, Ge, Al, Cr or their alloys. The first electrode ohmic contact layer 1031 can be an n-type gallium arsenide ohmic contact layer. The first roughening layer 104 can be an n-type Al (1-x) Ga X In 0.5 P 0.5 The first confinement layer 105 may be an n-type AlGaInP confinement layer, and the MQW active layer 106 may be a composite structure formed by alternately stacking AlGaInP layers with different material ratios; the second confinement layer 107 may be a p-type AlGaInP layer, and the second coarse layer 108 may be a p-type Al (1-x) Ga X In 0.5 P 0.5 , where 0≤x≤0.2. The DBR reflector layer 109 may include a combination of multiple pairs of first reflector layers and second reflector layers. The material chemical formula of the first reflector layer may be Al x Ga 1-x As, the material chemical formula of the second reflector layer can be Al y Ga 1-y As, preferably 0.45≤x≤0.75, 0≤y≤0.15; the number of combinations of the first reflector layer and the second reflector layer may be 15 to 20. The second ohmic contact window layer 110 may be a p-type GaP ohmic contact window layer.

[0049] The following reference Figure 1 , Figure 1a-1g The preparation process of the light emitting diode according to the present invention is described by taking a reverse polarity red light emitting diode as an example.

[0050] like Figure 1a As shown, first, an epitaxial method is used to prepare a light-emitting diode epitaxial wafer, including: providing a temporary substrate 100, such as a GaAs substrate; sequentially growing a buffer layer 101, a barrier layer 102, an n-type first ohmic contact layer 103, an n-type first roughening layer 104, an n-type first confinement layer 105, an MQW active layer 106, a p-type second confinement layer 107, a p-type second roughening layer 108, a DBR reflector layer 109 and a p-type second ohmic contact window layer 110 on the temporary substrate 100 to form a light-emitting diode epitaxial wafer structure. Among them, the n-type first ohmic contact layer 103 can be made of gallium arsenide. The material of the first roughening layer 104 can be Al (1-x) Ga X In 0.5 P 0.5(0≤x≤0.2). The n-type first confinement layer 105 and the p-type second confinement layer 107 can be made of AlGaInP materials with different component ratios. The MQW active layer 106 can be made of multiple pairs of AlGaInP well layer materials and barrier layer materials with different component ratios. The material of the second roughening layer 108 can be Al (1-x) Ga X In 0.5 P 0.5 (0≤x≤0.2). The p-type second ohmic contact window layer 110 may be made of GaP material.

[0051] In the embodiment of the present application, an epitaxial method such as MOCVD (metal organic chemical vapor deposition) or MBE (molecular beam epitaxy) is used to construct a composite DBR layer in the LED chip. The epitaxial structure includes a buffer layer, a barrier layer, an n-type first ohmic contact layer, an n-type first roughening layer, an n-type first confinement layer, a multi-quantum well MQW layer, a p-type second confinement layer, a p-type second roughening layer, a DBR reflector layer, and a p-type second ohmic contact window layer grown in sequence on the GaAs substrate. Therefore, no additional equipment and process are required for secondary deposition of the DBR reflector layer, which simplifies the preparation process. The DBR reflector layer prepared by the epitaxial method has high quality, high reflection efficiency, and is not easy to fall off. The DBR reflector layer 109 may include a composite combination of multiple pairs of first reflector layers and second reflector layers, and the material chemical formula of the first reflector layer is Al x Ga 1-x As, the material chemical formula of the second reflector layer is Al y Ga 1-y As, wherein preferably 0.45≤x≤0.75, 0≤y≤0.15, and the number of combinations of the first reflector layer and the second reflector layer is 15-20 groups.

[0052] Then, if Figure 1b As shown, a patterned DBR reflector layer 109 and a p-type second ohmic contact window layer 110 are fabricated on the light-emitting diode epitaxial wafer. Specifically, the DBR reflector layer 109 and the p-type second ohmic contact window layer 110 can be patterned by using a mask plate using photolithography, wet etching or dry etching techniques, and an opening portion 1092 and an opening portion 1102 are etched in the DBR reflector layer 109 and the p-type second ohmic contact window layer 110 to expose the second roughened layer 108 in the epitaxial layer structure.

[0053] Then, if Figure 1cAs shown, the side surfaces of the openings of the second roughening layer 108 and the DBR reflector layer 109 are roughened in the area corresponding to the openings of the DBR reflector layer 108. Specifically, a dry or wet process can be used for micro-etching surface roughening. Preferably, the area of ​​the second roughening layer 108 corresponding to the opening of the DBR reflector layer 109 and the side surfaces of the openings of the DBR reflector layer 109 are roughened in one micro-etching process. When wet etching is used, for the local roughening of the AlGaInP roughening layer and the side roughening of the openings of the AlGaAs DBR reflector layer, the etching solution used is preferably any one of HCL, H3PO5, CH3COOH, HF, HNO3, and H2O2, or a mixed solution of two or more. After the above-mentioned roughening process, a local roughening area, i.e., a second roughening area 1081, is obtained on the second roughening layer 108, and a roughening layer 1091 is obtained on the side surfaces of the openings of the DBR reflector layer.

[0054] Then, if Figure 1d As shown, a total reflector structure layer is fabricated on the p-type second ohmic contact window layer 110 of the light-emitting diode epitaxial wafer. Specifically, a metal reflector layer 201 may be deposited on the p-type second ohmic contact window layer 110 by evaporation or magnetron sputtering, and the metal reflector layer 201 is adjacent to the p-type second ohmic contact window layer 110 and extends into the DBR reflector layer 109 and the opening of the p-type second ohmic contact window layer 110. The material of the metal reflector layer 201 may be, for example, Al metal.

[0055] Then, if Figure 1e As shown, a permanent conductive substrate 200 and a p-side second electrode 202 are fabricated on an epitaxial wafer having a total reflector structure layer. Specifically, a bonding technology is used to bond the metal reflector layer 201, the conductive substrate 200 and the p-side second electrode 202. The conductive substrate 200 may be a Si substrate or a metal substrate, and the P electrode may be a metal electrode.

[0056] Then, if Figure 1f As shown, the temporary substrate 100, the buffer layer 101 and the barrier layer 102 are removed to expose the n-type gallium arsenide first ohmic contact layer 103. First, the temporary substrate 100 and the buffer layer 101 can be etched away using an etching solution that can selectively etch the temporary substrate 100 and the buffer layer 101, and then the barrier layer 102 can be etched away using an etching solution that can selectively etch the barrier layer 102 to expose the n-type gallium arsenide first ohmic contact layer 103.

[0057] Then, if Figure 1gAs shown, a patterned n-electrode 3011 and a patterned first electrode ohmic contact layer 1031 are fabricated on the epitaxial layer, exposing a partial region of the first roughened layer 104. The specific process is: first, a layer of metal is deposited as an n-electrode layer on the exposed n-type gallium arsenide first ohmic contact layer 103 by evaporation, sputtering or other techniques; then, the n-electrode layer and the first ohmic contact layer 103 are patterned by photolithography, etching or other techniques using a mask to obtain the patterned first electrode 3011 and the first electrode ohmic contact layer 1031. During the patterning process, the positions of the patterned first electrode 3011 and the first electrode ohmic contact layer 1031 are aligned with the positions of the openings 1092 of the DBR reflector layer 109. Preferably, the patterned first electrode 3011 and the first electrode ohmic contact layer 1031 correspond one to one and have the same patterned structure, and the area of ​​the patterned first electrode 3011 and the first electrode ohmic contact layer 1031 in the horizontal direction is less than or equal to the area of ​​the opening portion 1091 of the DBR reflector layer 109, so as to better scatter the light in the vertical direction of the electrode.

[0058] Next, a surface textured epitaxial layer is fabricated on the first roughened layer 104. Specifically, micro-etching roughening is performed on the surface of the area on the first roughened layer 104 where the first electrode 3011 and the first electrode ohmic contact layer 1031 are not provided, to form a first roughened area 1041, and the first roughened area 1041 is a light emitting surface. Similarly, the first roughened area 1041 can be micro-etched roughened by dry etching or wet etching to form a concave-convex scattering structure on the light emitting surface of the epitaxial wafer, so as to facilitate the emission of internal light to the outside of the LED and increase the external quantum efficiency of the LED. The light emitting diode structure finally obtained is as follows: Figure 1 shown.

[0059] The light emitting diode of the embodiment of the present invention has at least the following advantages:

[0060] 1. In the light-emitting diode of the embodiment of the present invention, the light-emitting surface electrode corresponds to the roughened area in the second roughened layer arranged on the side of the DBR reflector layer facing the light-emitting surface, so that the light in the vertical direction of the electrode can be scattered by the corresponding second roughened area, and is emitted from the device in a direction at a certain angle to the vertical direction, and is converted into effective output light, thereby avoiding the problem in the prior art that the light in the vertical direction of the electrode is repeatedly reflected between the electrode and the DBR reflector layer and finally converted into heat that cannot be effectively extracted, thereby improving the light extraction efficiency and external quantum efficiency of the LED.

[0061] 2. In the LED structure of the embodiment of the present invention, a total reflector structure layer is arranged on the side of the DBR reflector away from the light emitting direction. The arrangement of the total reflector structure layer makes up for the defect of low reflectivity of the DBR reflector layer to large-angle light, and can reflect the unreflected light to the light emitting end of the device, thereby further improving the light extraction efficiency and external quantum efficiency of the LED.

[0062] 3. In the LED structure of the embodiment of the present invention, the provision of the side roughening layer of the opening portion in the imaged DBR reflector layer can enable the light reflected by the metal reflector layer and that needs to pass through the imaged DBR side at a certain angle to be effectively extracted, further increasing the light extraction efficiency.

[0063] 4. In the LED structure of the embodiment of the present invention, the portion of the first roughening layer where the first electrode is not provided is roughened to form a surface-textured epitaxial layer, which can prevent the light emitted toward the light-emitting surface from being reflected back into the LED on the surface of the epitaxial layer, thereby increasing the light extraction efficiency.

[0064] 5. The embodiment of the present invention epitaxially grows a DBR reflector layer in the LED chip structure, which simplifies the chip manufacturing process and reduces production costs.

[0065] Figure 2 It is a schematic diagram of the structure of a light emitting diode according to another embodiment of the present application. Figure 2 The structure and manufacturing method of the light emitting diode shown are basically the same as Figure 1 The light emitting diodes of the embodiments shown are the same, and the only difference is the total reflector structure. The following mainly describes the difference in detail.

[0066] like Figure 2 As shown, the light-emitting diode structure of this embodiment includes, from the light-emitting surface to the substrate side, a first electrode layer formed by a patterned first electrode 3011, a first ohmic contact layer formed by a patterned first electrode ohmic contact layer 1031, a first roughening layer 104, a first confinement layer 105, an MQW active layer 106, a second confinement layer 107, a second roughening layer 108, a DBR reflector layer 109, a second ohmic contact window layer 110, an insulating dielectric layer 2011, a metal reflector layer 201, a conductive substrate 200, and a second electrode 202. It can be seen that Figure 2 and Figure 1 The main difference of the light-emitting diode is that an insulating dielectric layer 2011 is added between the p-type second ohmic contact window layer 110 and the metal reflector layer 201, and the insulating dielectric layer 2011 is adjacent to the p-type second ohmic contact window layer 110 and extends into the openings of the DBR reflector layer 109 and the p-type second ohmic contact window layer 110. The material of the insulating dielectric layer can be silicon oxide, aluminum oxide, etc.; and, conductive holes are also opened in the insulating dielectric layer 2011, and the metal reflector layer 201 is electrically contacted with the p-type second ohmic contact window layer 110 through the conductive holes in the insulating dielectric layer 2011; the metal layer 201, the insulating dielectric layer 2011 and the p-type second ohmic contact window layer 101 constitute an ODR total reflector structure.

[0067] Figure 2 The preparation process of the light emitting diode of the embodiment shown is similar to Figure 1 The embodiment 1 shown is also similar, and the only difference is the preparation of the insulating dielectric layer 2011. The same parts will not be repeated here, and only the differences will be described below. Figure 1a-1c The process of preparing epitaxial wafer structures with roughened structures, such as Figure 1c On this basis, instead of the first embodiment Figure 1d In the second embodiment, as Figure 2a As shown, an insulating dielectric layer 2011 is formed on the p-type second ohmic contact window layer 110 of the light-emitting diode epitaxial wafer, and the insulating dielectric layer 2011 is adjacent to the p-type second ohmic contact window layer 110 and extends into the openings of the DBR reflector layer 109 and the p-type second ohmic contact window layer 110; then, the insulating dielectric layer 2011 is patterned to form conductive holes therein; then, a metal reflector layer 201 is deposited on the insulating dielectric layer 2011 with the conductive holes formed therein, so that the metal reflector layer 201 is electrically in contact with the p-type second ohmic contact window layer 110 through the conductive holes in the insulating dielectric layer 2011. The subsequent preparation process of the light-emitting diode of this embodiment can refer to the first embodiment. Figure 1e-1g Finally, the light emitting diode structure obtained after the local roughening of the first roughened surface 104 is as follows Figure 2 shown.

[0068] Figure 2 The light emitting diode of the embodiment shown can obtain and Figure 1 The light emitting diode of the embodiment shown has the same advantages; in addition, due to the Figure 2 In the light-emitting diode structure of the illustrated embodiment, an insulating dielectric layer 2011 is added between the p-type second ohmic contact window layer 110 and the metal reflector layer 201. The metal layer 201, the insulating dielectric layer 2011 and the p-type ohmic contact window layer constitute an ODR total reflector structure. Compared with the total reflector structure layer constituted by a single metal reflector layer 201, it can more effectively reflect the large-angle light R2 not reflected by the DBR to the light-emitting end of the device, thereby obtaining a higher external quantum efficiency.

[0069] The exemplary embodiments of the present application are described above by way of example. However, it will be appreciated by those skilled in the art that the above description of the exemplary embodiments of the present disclosure is presented only for the purpose of illustration and description, and is not intended to be exhaustive or limit the present disclosure to the precise form disclosed. According to the above teachings, many modifications and variations are possible. The embodiments are selected and described to explain the principles of the present disclosure and its practical application, so that other technical personnel in the art can utilize the present disclosure and various embodiments, and have various modifications suitable for the specific purposes contemplated. Without departing from the spirit and scope of the present disclosure, replacement embodiments will become apparent to those skilled in the art to which the present disclosure belongs. Therefore, the scope of the present disclosure is limited by the appended claims rather than by the foregoing description and the exemplary embodiments described therein.

Claims

1. A light emitting diode structure, comprising, in order from the light emitting surface side: A first electrode layer, a first ohmic contact layer, a first roughening layer, a first confinement layer, an MQW active layer, a second confinement layer, a second roughening layer, a DBR reflector layer, a second ohmic contact window layer, a total reflector structure layer, a conductive substrate, and a second electrode; Wherein, the first electrode layer and the first ohmic contact layer have the same first patterned structure; The DBR reflector layer and the second ohmic contact window layer have the same second patterned structure, the second patterned structure includes an opening portion, and the opening portion is aligned with the position of the first electrode of the first electrode layer; The second roughened layer is provided with a second roughened region at a portion corresponding to the opening of the DBR reflector layer.

2. The light emitting diode structure according to claim 1, wherein: The total reflector structure layer is a metal reflector layer, which is adjacent to the second ohmic contact window layer and extends into the openings of the DBR reflector layer and the second ohmic contact window layer.

3. The light emitting diode structure according to claim 1, wherein: The total reflector structure layer comprises an insulating dielectric layer and a metal reflector layer, wherein the insulating dielectric layer is adjacent to the second ohmic contact window layer and extends into the openings of the DBR reflector layer and the second ohmic contact window layer; The insulating dielectric layer is provided with a conductive hole, and the metal reflector layer is in electrical contact with the second ohmic contact window layer through the conductive hole in the insulating dielectric layer; The metal reflector layer, the insulating dielectric layer and the second ohmic contact window layer constitute an ODR total reflector structure.

4. The light emitting diode structure according to claim 1, wherein: The first roughened layer is provided with a first roughened region on a portion where the first electrode is not provided.

5. The light emitting diode structure according to claim 1, wherein: A roughening layer is disposed on the side surface of the opening portion of the DBR reflector layer.

6. The light emitting diode structure according to claim 1, wherein: The area of ​​the second roughened region is greater than or equal to the area of ​​the first electrode.

7. A method for manufacturing a light emitting diode structure according to claim 1, comprising: Preparation of light-emitting diode epitaxial wafer: epitaxially growing a buffer layer, a barrier layer, a first ohmic contact layer, a first roughening layer, a first confinement layer, an MQW active layer, a second confinement layer, a second roughening layer, a DBR reflector layer and a second ohmic contact window layer on a temporary substrate in sequence to form a light-emitting diode epitaxial wafer; Patterning the DBR reflector layer and the second ohmic contact window layer to form corresponding openings in the DBR reflector layer and the second ohmic contact window layer; Roughening the second roughening layer in the area where the opening of the DBR reflector layer is located or roughening the side surfaces of the second roughening layer and the opening of the DBR reflector layer at the same time; Manufacturing a total reflection mirror structure layer on the second ohmic contact window layer of the light emitting diode epitaxial wafer; Fabricating a permanent conductive substrate and a second electrode on the total reflection mirror structure layer; removing the temporary substrate, the buffer layer and the barrier layer, and forming a first electrode layer on the exposed first ohmic contact layer; The first electrode layer and the first ohmic contact layer are patterned to obtain a patterned first electrode and a first electrode ohmic contact layer, so that the positions of the first electrode and the first electrode ohmic contact layer correspond to the positions of the openings of the DBR reflector layer.

8. The method for manufacturing a light emitting diode structure according to claim 7, wherein: The method of manufacturing a total reflection mirror structure layer on the second ohmic contact window layer of the light emitting diode epitaxial wafer includes: A metal reflector layer is formed on the second ohmic contact window layer of the light emitting diode epitaxial wafer. The metal reflector layer is adjacent to the second ohmic contact window layer and extends into the openings of the DBR reflector layer and the second ohmic contact window layer.

9. The method for manufacturing a light emitting diode structure according to claim 7, wherein: The method of manufacturing a total reflection mirror structure layer on the second ohmic contact window layer of the light emitting diode epitaxial wafer includes: Forming an insulating dielectric layer on the second ohmic contact window layer of the light-emitting diode epitaxial wafer, wherein the insulating dielectric layer is adjacent to the second ohmic contact window layer and extends into the DBR reflector layer and the opening portion of the second ohmic contact window layer; Patterning the insulating dielectric layer to form conductive holes therein; A metal reflector layer is deposited on an insulating dielectric layer having conductive holes, so that the metal reflector layer is in electrical contact with the second ohmic contact window layer through the conductive holes in the insulating dielectric layer. The metal layer, the insulating dielectric layer and the second ohmic contact window layer constitute an ODR total reflector structure.

10. The method for manufacturing a light emitting diode structure according to claim 7, further comprising: A roughening process is performed on a portion of the first roughened layer where the first electrode and the first ohmic contact layer are not provided, thereby forming a first roughened region.

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