WO2021115476A1

WO2021115476A1 - Substrate, led and manufacturing method therefor

Info

Publication number: WO2021115476A1
Application number: PCT/CN2020/136047
Authority: WO
Inventors: 蒋振宇; 闫春辉
Original assignee: 深圳第三代半导体研究院
Priority date: 2019-12-13
Filing date: 2020-12-14
Publication date: 2021-06-17
Also published as: CN111063773A; CN111063773B

Abstract

A substrate (100), an LED and a manufacturing method therefor. The substrate (100) comprises: a substrate body (110), wherein a plurality of transfer supporting structures (120) which are spacedly arranged from one another and protrude out of a main surface (111) on one side of the substrate body (110) are integrally formed on the main surface (111); and a transfer sacrificial layer (130) which is arranged on the main surface (111) of the substrate body (110) in a stacked manner and exposes the ends of the transfer supporting structures (120) away from the substrate body (110). The tolerance of the substrate body (110) to a specific etching liquid is greater than that of the transfer sacrificial layer (130). Through the above-mentioned manner, the provided substrate (100) can etch the transfer sacrificial layer (130) after LED units are generated subsequently, and thereby the transfer supporting structures (120) are used for supporting the LED units in a suspended manner relative to the substrate body (110), such that the adhesive force between the LED units and the substrate (100) is reduced and separation and transfer difficulty is reduced. Furthermore, the above-mentioned manner can improve the arrangement density of the LED units on the substrate (100), reduce the loss of the area of an LED chip and reduce the manufacturing cost of the LEDs.

Description

Substrate, LED and manufacturing method thereof

【Technical Field】

This application relates to the field of light-emitting diodes, in particular to a substrate, an LED and a manufacturing method thereof.

【Background technique】

Light emitting diodes (LEDs) are solid-state components that convert electrical energy into light. LEDs have the advantages of small size, high efficiency, and long life span, and are widely used in fields such as traffic indications and outdoor full-color displays. In particular, the use of high-power LEDs can realize semiconductor solid-state lighting, which has caused a revolution in the history of human lighting, and has gradually become a research hotspot in the current electronics field.

At present, LEDs are generally formed on the substrate by epitaxial growth, and the chip needs to be separated and transferred from the substrate in certain specific applications, such as Micro LEDs used in the display field, and used in flashlights, flashlights and car lights Vertical structure LED chips in other fields. How to effectively realize the separation between the LED and the substrate is a problem to be solved in the industry.

[Summary of the invention]

The present application provides a substrate, an LED, and a manufacturing method thereof, which can effectively reduce the adhesion between the subsequently generated LED unit and the substrate, and reduce the difficulty of separation and transfer.

In order to solve the above technical problems, a technical solution adopted in the present application is to provide a substrate, which includes a substrate body, and one main surface of the substrate body is integrally formed with spaced apart arrangement and protruding from each other. Multiple transfer support structures on the main surface; the transfer sacrificial layer is stacked on the main surface of the substrate body, and the end of the transfer support structure away from the substrate body is exposed, wherein the substrate body is resistant to a specific etching solution Greater than the transfer sacrificial layer.

In order to solve the above technical problems, another technical solution adopted by the present application is to provide a method for manufacturing a substrate. The method includes: providing a substrate main body, wherein one side of the main surface of the substrate main body is integrally formed with each other. A plurality of transfer support structures arranged at intervals; a transfer sacrificial layer is formed on the main surface of the substrate body, wherein the transfer sacrificial layer makes the end of the transfer support structure away from the substrate body exposed, and the substrate body is resistant to a specific etching solution The degree of acceptance is greater than that of the transfer sacrificial layer.

In order to solve the above technical problems, another technical solution adopted in this application is to provide a method for manufacturing an LED chip. The method includes: providing a substrate as described above; and forming a light-emitting epitaxial layer on the side of the transferred sacrificial layer away from the substrate body ; Pattern the light-emitting epitaxial layer to form multiple LED units; etch the transfer sacrificial layer so that the multiple LED units are separated from the transfer sacrificial layer and are supported by different transfer support structures.

In order to solve the above technical problem, another technical solution adopted in this application is to provide an LED, which includes a substrate body and a plurality of transfer support structures arranged at intervals integrally formed on one main surface of the substrate body ; Multiple LED units, multiple LED units are respectively supported by different transfer support structures, and maintain a certain interval with the substrate body.

The beneficial effect of the present application is: different from the state of the art, the present application provides a transfer sacrificial layer stacked on the main surface of the substrate body, and the main surface is also integrally formed with spaced apart and protruding from the main surface. The end of the transfer support structure away from the substrate body is exposed to the transfer sacrificial layer, and the tolerance of the substrate body to a specific etching solution is greater than that of the transfer sacrificial layer. After the LED unit is subsequently generated, the sacrificial layer is etched and transferred by a specific etchant, and the substrate body of the integrated structure and the transfer support structure are retained, so that the transfer support structure is used to suspend the LED unit relative to the substrate body. As a weakened structure in the subsequent process, it is convenient for the LED unit to be separated from the weakened structure under a relatively small external force. At the same time, since the transfer support structure is directly supported between the LED unit and the main body of the substrate, the arrangement density of the LED unit on the substrate can be increased, the area loss of the LED chip can be reduced, and the manufacturing cost of the LED can be reduced.

【Explanation of the drawings】

In order to more clearly describe the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings that need to be used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. among them:

Fig. 1 is a schematic top view of the structure of a substrate according to a first embodiment of the present application;

Fig. 2 is a first sectional structural diagram of the A-A section in Fig. 1;

Figure 3 is a second cross-sectional structure diagram of the A-A section in Figure 1

4 is a schematic diagram of the first process of the method for manufacturing the substrate of the present application;

5 is a schematic diagram of the structure corresponding to each stage of the manufacturing method of the substrate shown in FIG. 4;

Fig. 6 is a schematic flow chart of the manufacturing method of the LED of the present application;

FIG. 7 is a schematic flowchart of step S22 in FIG. 6;

FIG. 8 is a schematic flowchart of step S23 in FIG. 6;

FIG. 9 is a schematic flowchart of step S24 in FIG. 6;

10 is a schematic diagram of the first structure corresponding to each step of the manufacturing method of the LED of the present application;

11 is a schematic diagram of a second structure corresponding to each step of the manufacturing method of the LED of the present application;

Fig. 12 is a schematic diagram of the structure of the LED of the present application.

【Detailed ways】

The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

As shown in FIGS. 1-2, the substrate 100 according to the first embodiment of the present application includes: a substrate body 110, a transfer support structure 120, and a transfer sacrificial layer 130. The transfer support structure 120 is disposed on the main surface 111 of one side of the substrate body 110, the transfer support structure 120 and the substrate body 110 are an integral structure, and a plurality of transfer support structures 120 are spaced apart from each other and protrude from the main surface 111.

Further, a transfer sacrificial layer 130 is provided on one side of the main surface 111 of the substrate body 110, and a plurality of openings 131 spaced apart from each other are provided on the transfer sacrificial layer 130, and the arrangement of the plurality of openings 131 may be regular. , It can also be irregularly distributed. In this embodiment, a plurality of openings 131 are arranged in a honeycomb pattern on the main surface 111, that is, a certain opening 131 is selected as a reference, and the surrounding openings 131 are distributed in the center of the certain opening 131. At the vertex position of the regular hexagon.

Further, the number of the transfer support structure 120 is equal to the number of the opening 131, and the transfer support structure 120 corresponds to the opening 131 one-to-one. The transfer support structure 120 penetrates through the opening 131, and the end 121 of the transfer support structure 120 away from the substrate body 110 is exposed through the plurality of openings 131.

The transfer support structure 120 is used as a weakened structure in the subsequent process, and then after the corresponding LED unit is subsequently formed, a part of the transfer sacrificial layer 130 can be removed, so that the transfer support structure 120 for supporting the LED unit is exposed, and then used The transfer support structure 120 suspends the LED unit relative to the substrate body 110 to reduce the adhesion between the LED unit and the substrate 100. For example, an etching process may be performed on the transfer sacrificial layer 130 until a part of the transfer support structure 120 is exposed. The etching process can also be implemented by a dry etching process or a wet etching process.

Wherein, the height d1 of the transfer support structure 120 is in the range of 0.1-10 micrometers, and the cross-sectional dimension r1 of the transfer support structure 120 along the parallel direction D1 of the main surface 111 is in the range of 0.1-10 micrometers.

Further, materials with different tolerances to specific etchants can be selected as the material of the substrate body 110, the material of the transfer support structure 120, and the material of the transfer sacrificial layer 130, specifically, the substrate body 110 and the transfer support structure 120 of an integrated structure The tolerance for a specific etchant is greater than that of the transferred sacrificial layer 130. Therefore, in the subsequent process, when the transfer sacrificial layer 130 is etched with a specific etchant, the substrate body 110 and the transfer support structure 120 for supporting the LED unit are retained.

The material of the substrate body 110 and the transfer support structure 120 mentioned above may include sapphire, and the material of the transfer sacrificial layer 130 may include SiO ₂ , SiN or Al ₂ O ₃ . Among them, the specific etchant can be mixed with hydrofluoric acid and ammonium fluoride in a certain ratio. Since hydrofluoric acid has a strong corrosive effect on silicon-containing substances, the specific etchant can effectively transfer _{SiO 2} The sacrificial layer 130 is etched.

In other embodiments, the material of the substrate body is GaAs, the material of the transfer sacrificial layer is AlGaAs, InGaAs, or AlInGaAs; the specific etchant is organic acid, or organic acid/H ₂ O ₂ mixed solution, or NH ₄ OH/H ₂ O ₂ mixed solution, or H ₃ PO ₄ /H ₂ O ₂ mixed solution.

The transfer sacrificial layer 130 has a continuous structure. Therefore, the transfer sacrificial layer 130 can be continuously etched with a specific etchant, and there is no need to add a specific etchant to the transfer sacrificial layer 130 multiple times, thereby improving the etching efficiency.

Further, the specific etchant mentioned above may be an etchant for anisotropically etch-transferring the sacrificial layer 130 to etch and transfer the sacrificial layer 130 at different rates in different exposure planes.

Different from the state of the art, in this application, a transfer sacrificial layer is laminated on the main surface of the substrate body, and the main surface is also integrally formed with a plurality of transfer support structures spaced apart from each other and protruding from the main surface. The end of the transfer support structure away from the substrate main body is exposed to the transfer sacrificial layer, and the substrate main body is more resistant to a specific etching solution than the transfer sacrificial layer. After the LED unit is subsequently generated, the sacrificial layer is etched and transferred by a specific etchant, and the substrate body of the integrated structure and the transfer support structure are retained, so that the transfer support structure is used to suspend the LED unit relative to the substrate body. As a weakened structure in the subsequent process, it is convenient for the LED unit to be separated from the weakened structure under a relatively small external force. At the same time, since the transfer support structure is directly supported between the LED unit and the main body of the substrate, the arrangement density of the LED unit on the substrate can be increased, the area loss of the LED chip can be reduced, and the manufacturing cost of the LED can be reduced.

As shown in FIG. 3, further, each transfer support structure 120 respectively includes a support pillar 122 buried in the transfer sacrificial layer 130 and a support head 123 connected to the support pillar 122 and protruding from the transfer sacrificial layer 130. It can be understood that the transfer sacrificial layer 130 is filled between the supporting pillars 122.

Wherein, the outer side surface of the support head 123 transitions in an arc in the direction away from the substrate body 110, and the cross-sectional dimension r2 of the support head 123 along the parallel direction D1 of the main surface 111 is in the direction away from the substrate body (the opposite direction of D2) The upper part gradually becomes smaller to form a yurt form, which facilitates the separation of subsequent LED units. In other embodiments, the supporting head 123 may be designed in a cylindrical shape, a hemispherical shape, a conical shape, a truncated cone shape, or any other shape.

Wherein, the height d2 of the support column 122 is in the range of 0.1-10 microns, the cross-sectional dimension r2 of the support column 122 along the parallel direction D1 of the main surface 111 is in the range of 0.1-10 microns; the height d3 of the support head 123 is in the range of 0.1 Within -10 microns.

As shown in FIGS. 4 and 5, the present application also proposes a method for manufacturing the substrate 100, which is used for manufacturing the substrate 100 in the above-mentioned embodiment. The method includes the following steps:

S11: Provide a substrate body 110.

The one side main surface 111 of the substrate main body 110 will be patterned to form a plurality of transfer support structures 120 spaced apart from each other on the one side main surface 111 of the substrate main body 110. The material of the integrated substrate body 110 and the transfer support structure 120 may specifically include sapphire.

S12: A transfer sacrificial layer 130 is formed on the main surface 111 of one side of the substrate body 110.

Specifically, the material of the transfer sacrificial layer 130 may specifically include SiO ₂ , SiN, or Al ₂ O ₃ . Wherein, a silica sol layer can be formed on one main surface 111 of the substrate body 110, and the substrate body 110 with the silica sol layer formed on the surface can be dried to prepare SiO ₂ transfer on the substrate body 110. Sacrificial layer 130; or use PECVD method to deposit SiO ₂ or SiN transfer sacrificial layer 130 on the main surface 111 of the substrate body 110; or use LPCVD method to deposit SiO ₂ or SiN transfer sacrificial layer on the main surface 111 of the substrate body 110 _{130; or use magnetron sputtering to grow Al 2} O ₃ transfer sacrificial layer 130 on the main surface 111 of the substrate body 110; or use ALD (Atomic Layer Deposition, atomic layer deposition) method to deposit SiO ₂ or Al ₂ O ₃ transfer Sacrificial layer 130.

Wherein, the transfer sacrificial layer 130 may be patterned to form a plurality of openings 131 spaced apart from each other in the transfer sacrificial layer 130, the transfer support structure 120 penetrates the openings 131, and the transfer support structure 120 is far away from the liner. The end 121 of the bottom body 110 is exposed through a plurality of openings 131.

The above-mentioned patterning process may use a suitable patterning technique to form the opening 131, for example, dry etching, wet etching or other suitable techniques. For example, a mask is covered on the transfer sacrificial layer 130. The transfer sacrificial layer 130 in the position not covered by the mask is removed by an etching technique, and a plurality of openings 131 are formed. The shape of the opening 131 may be rounded square, circular or elliptical, and the opening area of the opening 131 may be equal or unequal, which is not limited herein.

The substrate body 110 and the transfer support structure 120 are more resistant to a specific etchant than the transfer sacrificial layer 130.

The transfer support structure 120 is used as a weakened structure in the subsequent process. In the subsequent process, when the transfer sacrificial layer 130 is etched with a specific etchant, the substrate body 110 and the transfer support structure 120 for supporting the LED unit are retained. The transfer support structure 120 is used to suspend the LED unit relative to the substrate body 110 to facilitate the separation of the LED unit from the weakened structure under a relatively small external force. At the same time, since the transfer support structure 120 is directly supported between the LED unit and the substrate main body, the arrangement density of the LED unit on the substrate can be increased, the area loss of the LED chip can be reduced, and the manufacturing cost of the LED can be reduced.

Step S11 further includes: patterning the main surface 111 of the substrate body 110 to form a plurality of supporting pillars 122 spaced apart from each other on the main surface 111 of the substrate body 110 and the supporting pillars. 122 connected to the support head 123. The cross-sectional dimension r2 of the support head 123 along the parallel direction D1 of the main surface 111 gradually becomes smaller in the direction away from the substrate body 110 (the opposite direction of D2).

Specifically, a mask is covered on one side of the main surface 111 of the substrate body 110, and at least part of the substrate body 110 in the position not covered by the mask is removed by controlling the etching time to form a plurality of supports spaced apart from each other. The column 122 and the support head 123 connected with the support column 122.

After step S12, the support pillar 122 is buried in the transfer sacrificial layer 130, and the support head 123 is connected to the support pillar 122 and protrudes from the transfer sacrificial layer 130.

The following will take the substrate 100 as an example to describe the manufacturing method of the LED of the present application.

As shown in FIG. 6 and FIG. 10, the present application also proposes a method for manufacturing an LED chip, which includes:

S21: Provide a substrate 100.

Specifically, the substrate 100 is the substrate 100 in the above-mentioned embodiment. For the specific structure, please refer to the relevant description of the substrate 100 in the above-mentioned embodiment, which will not be repeated here.

S22: forming a light-emitting epitaxial layer 140 on the side of the transfer sacrificial layer 130 away from the substrate body 110.

Specifically, the light-emitting epitaxial layer 140 has a multilayer structure, and specifically includes: a first conductivity type semiconductor layer 141, a quantum well layer 142, and a second conductivity type semiconductor layer 143.

The MOCVD method may be used to sequentially grow the first conductive type semiconductor layer 141, the quantum well layer 142, and the second conductive type semiconductor layer 143 on the side of the transfer sacrificial layer 130 away from the substrate body 110. The current diffusion layer 144 is further formed by other processes.

Wherein, the quantum well layer 142 may be an MQWs structure, and the MQWs structure includes a plurality of stacked single-layer quantum wells (SQW). The MQWs structure retains the advantages of SQW and has a larger active area that allows high optical power. In other embodiments, the first conductivity type semiconductor layer 141 and the second conductivity type semiconductor layer 143 may be a single-layer or multi-layer structure of any other suitable materials having different conductivity types.

S23: Pattern the light-emitting epitaxial layer 140 to form a plurality of LED units.

Specifically, an etching process is applied to pattern the light-emitting epitaxial layer 140 and the current diffusion layer 144, wherein the above-mentioned etching process may include dry etching, wet etching, or a combination thereof.

The LED unit may be a flip-chip light-emitting diode, a vertical light-emitting diode, or a front-mounted light-emitting diode, which is not limited here.

S24: Etching the transfer sacrificial layer 130 to separate the plurality of LED units from the transfer sacrificial layer 130, and are respectively supported on the substrate body 110 by different transfer support structures 120.

The transfer sacrificial layer 130 is etched with a specific etchant, and the sacrificial layer 130 can be transferred by etching, so that different transfer support structures 120 are exposed. One end of the transfer support structure 120 is supported by the substrate body 110, and the other end is supported by the substrate body 110. LED unit.

The transfer support structure 120 serves as a weakened structure in the subsequent process, and the LED unit can be separated from the weakened structure under the action of external force.

As shown in FIGS. 7 and 10, when the LED unit is a flip-chip light emitting diode, step S22 includes the following steps:

S221: Form a buffer layer 150 on the side of the transfer sacrificial layer 130 away from the substrate body, wherein the buffer layer 150 covers the end 121 of the transfer support structure 120 and forms a flat surface 151 on the side away from the substrate body 110.

Specifically, the buffer layer 150 is a composite buffer layer structure of AlN, AlGaN, GaN, or AlN/AlGaN/GaN.

There are two main methods for preparing the buffer layer 150, one is prepared by the traditional MOCVD method, that is, the organic compounds of group III elements and the hydrides of group V and VI elements are used as crystal growth source materials, and the thermal decomposition reaction method is adopted. The vapor phase epitaxial growth is performed on the substrate 100. In other embodiments, the deposition process can also be completed by means of physical vapor deposition, sputtering, hydrogen phase deposition, or atomic layer deposition.

The buffer layer 150 covers the end 121 of the transfer support structure 120 and the buffer layer 150 includes a flat surface 151 on the side away from the substrate body 110

Due to the stress caused by the difference in the coefficient of thermal expansion between the transfer sacrificial layer 130 and the transfer support structure 120, fracture occurs at the contact surface between the transfer sacrificial layer 130 and the end 121 of the transfer support structure 120, thereby the transfer sacrificial layer 130 It is easily separated from the transfer support structure 120. Therefore, in this embodiment, the buffer layer 150 can be adjusted to reduce stress and defects at the contact surface between the transfer sacrificial layer 130 and the end 121 of the transfer support structure 120.

S222: forming a light emitting epitaxial layer 140 including a first conductive type semiconductor layer 141, a quantum well layer 142, and a second conductive type semiconductor layer 143 on the flat surface 151.

A first conductive type semiconductor layer 141 is grown on the flat surface 151. The first conductive type semiconductor layer 141 is an n-type GaN layer, such as a GaN layer doped with at least one of Si, Ge, and Sn. Next, a quantum well layer 142 is grown on the first conductive type semiconductor layer 141. The quantum well layer 142 can have any of the following structures: single-layer quantum well (SQW) and InGaN/GaN multilayer quantum well (MQW). Then, a second conductive type semiconductor layer 143 is grown on the quantum well layer 142. The second conductive type semiconductor layer 143 is a p-type GaN layer, such as GaN doped with at least one of Mg, Zn, Be, Ca, Sr, and Ba. Floor. In this way, the light-emitting epitaxial layer 140 is completed.

S223: forming a current diffusion layer 144 on the light-emitting epitaxial layer 140.

Finally, an electron beam evaporation or magnetron sputtering method is used to grow a current diffusion layer 144 on the second conductivity type semiconductor layer 143 of the light-emitting epitaxial layer 140.

The current spreading layer 144 may use a transparent conductive material, such as indium tin oxide (ITO). In other embodiments, the current diffusion layer 144 may be a metal mirror layer including silver (Ag), nickel (Ni), platinum (Pt), or other suitable metals.

As shown in FIG. 8 and FIG. 10, step S23 includes:

S231: Pattern the current diffusion layer 144 and the light-emitting epitaxial layer 140 once to form a plurality of mesa structures 170 that are spaced apart from each other and expose a portion of the first conductivity type semiconductor layer 141.

Specifically, an etching process is applied to remove part of the quantum well layer 142 and the second conductive type semiconductor layer 143 to form the first trench 161 and the first trench 161 on the quantum well layer 142 and the second conductive type semiconductor layer 143 The quantum well layer 142 and the second conductive type semiconductor layer 143 are divided into a plurality of mesa structures 170 arranged in an array at intervals, and the first conductive type semiconductor layer 141 is exposed in the region of the first trench 161. Wherein, the above-mentioned etching process may include dry etching, wet etching or a combination thereof.

In an alternative embodiment, a mask may be further used to form the first trench 161 through the following processes: forming a mask on the second conductivity type semiconductor layer 143, patterning the mask using a photolithography process, and using a patterned The mask serves as an etching mask to etch the light emitting epitaxial layer 140 to form the first trench 161.

Further, the patterned current diffusion layer 144 may be used as a mask, and is not removed after the first trench 161 is formed by etching. The current diffusion layer 144 may include multiple metal films that serve various functions. The current diffusion layer 144 may include a metal film as a contact electrically connected to the p-type semiconductor layer. The current spreading layer 144 may use a transparent conductive material, such as indium tin oxide (ITO). In other embodiments, the current diffusion layer 134 may be a metal mirror layer including silver (Ag), nickel (Ni), platinum (Pt), or other suitable metals.

S232: forming the first conductive type electrode 151 and the second conductive type electrode 151 and the second conductive type electrically connected to the first conductive type semiconductor layer 141 and the second conductive type semiconductor layer 143 on the exposed part of the first conductive type semiconductor layer 141 and the current diffusion layer 144, respectively Type electrode 152.

The first conductive type semiconductor layer 141 is an n-type semiconductor layer (for example, an n-type GaN layer), the second conductive type semiconductor layer 143 is a p-type semiconductor layer (for example, a p-type GaN layer), and the corresponding first conductive type electrode 151 It is an n-type electrode, and the corresponding second conductivity type electrode 152 is a p-type electrode.

Specifically, Cr/Al/Ti metal is fabricated on the exposed part of the surface of the first conductivity type semiconductor layer 141 to form the first conductivity type electrode 151, so the first conductivity type electrode 151 is an n-type electrode, and the first conductivity type electrode 151 It is electrically connected to the first conductive type semiconductor layer 141. For example, in this embodiment, the first conductive type electrode 151 is electrically connected to the first conductive type semiconductor layer 141 through direct contact.

The Ni/Au metal is fabricated on the current diffusion layer 144 to form the second conductivity type electrode 152. Therefore, the second conductivity type electrode 152 is a p-type electrode, and the second conductivity type electrode 152 is electrically connected to the second conductivity type semiconductor layer 143.

S233: Perform secondary patterning on the first conductive type semiconductor layer 141 and the buffer layer 150 from the spaced area between the mesa structures 170 to form a plurality of LED units.

Each LED unit includes at least one mesa 170, at least one first conductivity type electrode 151, and at least one second conductivity type electrode 152.

Specifically, an etching process is applied to remove the first conductive type semiconductor layer 141 and the buffer layer 150 between the mesa structures 170 to form the quantum well layer 142 and the second conductive type semiconductor layer 143 to define each LED unit的 each second groove 162. Wherein, the second trench 162 may be formed through a process including a photolithography patterning process and an etching process.

Further, various appropriate processes, such as ALD, PECVD, sputtering or spraying, are used on the upper surface and peripheral sidewall surfaces of the reflective layer, the sidewall surface of the first trench 161, the sidewall surface of the second trench 162, and the first conductivity type. The outer edge of the electrode 151 and the outer edge of the second conductivity type electrode 152 are covered with an insulating layer 190. The insulating layer 190 can be made of aluminum nitride, silicon dioxide, silicon nitride, aluminum oxide, Bragg reflector DBR, silica gel, Made of either resin or acrylic.

It should be noted that the surface of the first conductive type electrode 151 away from the current diffusion layer 144 and the surface of the second conductive type electrode 152 away from the current diffusion layer 144 are at least partially uncovered with the insulating layer 190, which is an exposed surface.

On the exposed surfaces of the first conductive type electrode 151 and the second conductive type electrode 152, and on the surface of the insulating layer 190 located between the first conductive type electrode 151 and the second conductive type electrode 152, printing, electroplating, The electron beam evaporation or magnetron sputtering process manufactures the first pad 181 and the second pad 182 that are insulated from each other. The first pad 181 is electrically connected by directly contacting the first conductive type electrode 151, and the second pad 182 It is electrically connected to the second conductivity type electrode 152 through direct contact, thus completing the LED unit.

It is worth noting that in this application, although the flip-chip structure LED is described as an example, the substrate 100 of the present application is also suitable for manufacturing vertical structure LEDs and front-mounted structure LEDs.

In an embodiment, the material of the substrate body 110 is GaAs; in the light-emitting epitaxial layer 140, the material of the first conductive type semiconductor layer 141 is AlInGaP; the material of the quantum well layer 142 is AlInGaP; the material of the second conductive type semiconductor layer 143 The material is AlInP; the material of the current diffusion layer 144 is GaP; the material of the first conductivity type electrode 151 and the second conductivity type electrode 152 is Au.

As shown in FIG. 9 and FIG. 11, step S24 includes:

S241: Perform one etching on the transfer sacrificial layer 130 from the spaced area between the LED units to form a groove 102 extending to a certain depth inside the transfer sacrificial layer 130.

S242: Use a specific etchant to etch the transfer sacrificial layer 130 from the groove 102.

Specifically, in order to ensure the etching depth of the transfer sacrificial layer 130, the transfer sacrificial layer 130 needs to be etched once from the spaced area between the LED units.

As shown in FIG. 12, the LED 200 according to an embodiment of the present application includes: a substrate body 110, a plurality of transfer support structures 120 integrally formed on one main surface 111 of the substrate body 110, and an LED unit 201.

The number of LED units 201 is multiple, and the multiple LED units 201 are respectively supported by different transfer support structures 120 and kept at a certain distance from the substrate body 110. The LED units 201 are the LED units manufactured in the above embodiments. Wherein, each LED unit includes at least one mesa structure 170, at least one first conductivity type electrode 151, and at least one second conductivity type electrode 152.

The above are only implementations of this application, and do not limit the scope of this application. Any equivalent structure or equivalent process transformation made using the content of the description and drawings of this application, or directly or indirectly applied to other related technical fields, The same reasoning is included in the scope of patent protection of this application.

Claims

An LED, wherein the LED includes:

A substrate body and a plurality of transfer support structures that are integrally formed on one main surface of the substrate body and arranged at intervals;

A plurality of LED units, the plurality of LED units are respectively supported by different transfer support structures, and are kept at a certain distance from the substrate main body.
A substrate, wherein the substrate includes:

A substrate main body, on one main surface of the substrate main body, a plurality of transfer support structures arranged at intervals and protruding from the main surface are integrally formed;

The transfer sacrificial layer is stacked on the main surface of the substrate body, and the transfer support structure is exposed away from the end of the substrate body, wherein the substrate body is resistant to a specific etching solution The degree is greater than the transfer sacrificial layer.
The substrate according to claim 2, wherein the material of the substrate body is sapphire, and the material of the transfer sacrificial layer is SiO 2 , SiN or Al 2 O 3 .
3. The substrate according to claim 2, wherein the material of the substrate body is GaAs, and the material of the transfer sacrificial layer is AlGaAs, InGaAs or AlInGaAs;

The specific etchant is organic acid, or organic acid/H 2 O 2 mixed solution, or NH 4 OH/H 2 O 2 mixed solution, or H 3 PO 4 /H 2 O 2 mixed solution.
The substrate according to claim 2, wherein each of the transfer support structures respectively includes a support pillar buried in the transfer sacrificial layer and a support head connected to the support pillar and protruding from the transfer sacrificial layer , The cross-sectional dimension of the supporting head along the parallel direction of the main surface gradually becomes smaller in the direction away from the substrate body.
The substrate according to claim 5, wherein the supporting head has at least one of a cylindrical shape, a hemispherical shape, a conical shape, or a truncated cone shape.
A method for manufacturing a substrate, wherein the method includes:

Providing a substrate body, wherein a plurality of transfer support structures spaced apart from each other are integrally formed on one main surface of the substrate body;

A transfer sacrificial layer is formed on the main surface of the substrate main body, wherein the transfer sacrificial layer exposes the transfer support structure away from the end of the substrate main body, and the substrate main body is specific to a specific etching solution. The tolerance is greater than the transfer sacrificial layer.
7. The method according to claim 7, wherein each of the transfer support structures respectively comprises a support pillar buried in the transfer sacrificial layer and a support head connected to the support pillar and protruding from the transfer sacrificial layer, The cross-sectional size of the support head along the parallel direction of the main surface gradually becomes smaller in the direction away from the substrate body.
A method for manufacturing an LED, wherein the method includes:

A substrate is provided, the substrate includes a substrate main body and a transfer sacrificial layer, and a plurality of transfer support structures arranged at intervals and protruding from the main surface are integrally formed on one main surface of the substrate main body, The substrate body is stacked on the main surface of the substrate body, and the transfer support structure is exposed away from the end of the substrate body, wherein the substrate body is more resistant to a specific etching solution than the Transfer the sacrificial layer;

Forming a light-emitting epitaxial layer on the side of the transfer sacrificial layer away from the substrate body;

Patterning the light-emitting epitaxial layer to form a plurality of LED units;

The transfer sacrificial layer is etched, so that the plurality of LED units are separated from the transfer sacrificial layer, and are supported by different transfer support structures, respectively.
9. The method according to claim 9, wherein the step of forming a light-emitting epitaxial layer on the side of the transfer sacrificial layer away from the substrate body comprises:

Forming a buffer layer on the side of the transfer sacrificial layer away from the substrate body, wherein the buffer layer covers the end of the transfer support structure and forms a flat surface on the side away from the substrate body;

Sequentially forming a first conductivity type semiconductor layer, a quantum well layer, a second conductivity type semiconductor layer, and a current diffusion layer on the flat surface;

The step of patterning the light-emitting epitaxial layer includes:

The current diffusion layer, the second conductivity type semiconductor layer, the quantum well layer, and the first conductivity type semiconductor layer are patterned once to form a plurality of step structures that are spaced apart from each other and expose a portion of the first conductivity type semiconductor layer ；

On the exposed portion of the first conductivity type semiconductor layer and the current diffusion layer are formed a first conductivity type electrode and a second conductivity type that are electrically connected to the first conductivity type semiconductor layer and the second conductivity type semiconductor layer, respectively Type of electrode;

The first conductive type semiconductor layer and the buffer layer are secondarily patterned from the spaced area between the stepped structures to form a plurality of the LED units, wherein each of the LED units includes at least one The mesa structure, at least one electrode of the first conductivity type and at least one electrode of the second conductivity type.
9. The method of claim 9, wherein the step of etching the transfer sacrificial layer comprises:

Etch the transfer sacrificial layer once from the spaced area between the LED units to form a groove extending to a certain depth inside the transfer sacrificial layer;

The transfer sacrificial layer is etched from the groove using a specific etching solution.
The method according to claim 9, wherein the material of the substrate body is sapphire, and the material of the transfer sacrificial layer is SiO 2 , SiN or Al 2 O 3 .
9. The method according to claim 9, wherein the material of the substrate body is GaAs, and the material of the transfer sacrificial layer is AlGaAs, InGaAs or AlInGaAs;

The specific etchant is organic acid, or organic acid/H 2 O 2 mixed solution, or NH 4 OH/H 2 O 2 mixed solution, or H 3 PO 4 /H 2 O 2 mixed solution.
9. The method according to claim 9, wherein each of the transfer support structures respectively comprises a support post buried in the transfer sacrificial layer and a support head connected to the support post and protruding from the transfer sacrificial layer, The cross-sectional size of the support head along the parallel direction of the main surface gradually becomes smaller in the direction away from the substrate body.
The method according to claim 9, wherein the transfer sacrificial layer has a continuous structure.
9. The method according to claim 9, wherein the specific etchant is an etchant for anisotropically etching the transfer sacrificial layer to etch the transfer sacrificial layer at different rates in different exposure planes.
The method according to claim 10, wherein the buffer layer is a composite buffer layer structure of AlN, AlGaN, GaN, or AlN/AlGaN/GaN.
The method according to claim 10, wherein the current diffusion layer is made of a transparent conductive material, or the current diffusion layer is a metal mirror layer.