Weakening structure of light emitting device and method for manufacturing the same

Abstract

The application relates to a weakening structure of a light-emitting device and a preparation method of the weakening structure, wherein the preparation method of the weakening structure of the light-emitting device comprises the following steps: firstly providing a substrate provided with the light-emitting device, then forming a protective layer on the light-emitting device, and then performing first etching on the substrate of a non-device area based on the protective layer and removing the protective layer, so that the first thinning of the substrate is realized. Then, a mask layer is formed on the substrate after the first etching and the light-emitting device, then the second etching is performed on the substrate of the non-device area based on the patterned mask layer, then the anisotropic etching is performed on the device area and the exposed substrate, the structure column is formed and the mask layer is removed, the second thinning of the substrate is realized, the structure column and the substrate of the device area after the first etching, i.e. the structure arm, constitute a T-shaped weakening structure, the light-emitting device on the T-shaped weakening structure can be selectively picked up by using a common transfer head, the efficiency of the massive transfer of the light-emitting device is improved, and the cost of the massive transfer of the light-emitting device is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, in particular to a weakening structure of a light-emitting device and a preparation method thereof. BACKGROUND

[0002] Micro Light Emitting Diode (Micro LED) has the characteristics of self-luminous display, and is a full solid-state light-emitting diode, which has the characteristics of long service life, high brightness, low power consumption, small size, super high resolution, and can be applied to extreme environments such as high temperature or radiation. Compared with OLED (Organic Light-Emitting Diode) technology which is also a self-luminous display, Micro LED not only has higher efficiency and longer service life, and the material is relatively stable and not easily affected by the environment, but also can avoid the phenomenon of residual image.

[0003] Micro LED display technology is to miniaturize and array the traditional LED structure, and use CMOS (Complementary Metal Oxide Semiconductor) integrated circuit process to make driving circuit to realize the display technology of addressing control and individual driving of each pixel point. In the industrialization process of Micro LED chip, there is a problem that the silicon substrate after bonding is too thick, which makes the mass transfer efficiency of Mirco LED low, and the silicon (Si) substrate needs to be thinned after CMOS bonding. In the preparation process of Micro LED display device, up to several million or even tens of millions of Micro LED chips need to be transferred from the growth substrate to the driving backboard, which requires the transfer of Micro LED. In the transfer process, each Micro LED on the growth substrate of the prior art has the same weakening structure, and the weakening structure is formed by forming an anchor structure, and different sizes require different photomasks, which requires higher cost and difficulty.

[0004] Therefore, the prior art Micro LED transfer method needs a weakening structure scheme that can thin the substrate while reducing the cost. SUMMARY

[0005] Therefore, it is necessary to provide a weakening structure of a light-emitting device and a preparation method of the weakening structure of the light-emitting device to thin the substrate of the light-emitting device, so as to improve the mass transfer efficiency of the light-emitting device.

[0006] In order to achieve the above-mentioned purpose, in one aspect, the present application provides a preparation method of a weakening structure of a light-emitting device. The preparation method of the weakening structure of the light-emitting device comprises:

[0007] providing a substrate, the substrate comprising a device region and a non-device region; wherein the device region is provided with a light emitting device;

[0008] forming a protection layer on the light emitting device;

[0009] performing a first etching on the substrate of the non-device region based on the protection layer;

[0010] removing the protection layer;

[0011] forming a mask layer on the substrate after the first etching and the light emitting device;

[0012] performing a second etching on the substrate of the non-device region based on the patterned mask layer; wherein the etching width of the second etching is less than the etching width of the first etching in parallel to the substrate direction;

[0013] performing an anisotropic etching on the exposed substrate of the device region to form a structure column;

[0014] removing the mask layer.

[0015] In one embodiment, a sub-substrate and a structure arm are formed based on the first etching; wherein the structure arm is disposed on the sub-substrate, and the light emitting device is disposed on the structure arm;

[0016] Before performing the second etching on the substrate of the non-device region based on the patterned mask layer, the method for preparing a light emitting device weakening structure further comprises:

[0017] forming the patterned mask layer by photoetching and developing, the patterned mask layer being located on the sidewall of the structure arm, the sidewall of the light emitting device, and the upper surface of the light emitting device.

[0018] In one embodiment, the etching depth of the first etching is 300-500 microns in the direction perpendicular to the substrate.

[0019] In one embodiment, the etching depth of the second etching is greater than the etching depth of the first etching in the direction perpendicular to the substrate, and the etching depth of the second etching is 1 / 3 of the thickness of the light emitting device.

[0020] In one embodiment, the substrate is a silicon <111> substrate, and the anisotropic etching on the exposed substrate of the device region comprises:

[0021] performing an anisotropic etching on the exposed substrate of the device region by using a potassium hydroxide solution.

[0022] In one of the embodiments, the weight percentage of potassium hydroxide in the potassium hydroxide solution is 45%-60%, and the temperature of the potassium hydroxide solution ranges from 40°C to 60°C.

[0023] The preparation method of the light emitting device weakening structure comprises the following steps: providing a substrate provided with a light emitting device; forming a protective layer on the light emitting device; performing first etching on the substrate in the non-device area based on the protective layer; and removing the protective layer, so as to realize the first thinning of the substrate. Then, a mask layer is formed on the substrate and the light emitting device after the first etching, and then the substrate in the non-device area is etched based on the patterned mask layer, and the substrate in the device area is anisotropically etched to form a structure column and remove the mask layer, so as to realize the second thinning of the substrate. In addition, the structure column and the substrate in the device area after the first etching, i.e. the structure arm, form a T-shaped weakening structure, so that the light emitting device on the T-shaped weakening structure can be selectively picked up by using a common transfer head, thereby improving the efficiency of the mass transfer of the light emitting device and reducing the cost of the mass transfer of the light emitting device.

[0024] In another aspect, the application provides a weakening structure of a light emitting device. The weakening structure of the light emitting device comprises:

[0025] a substrate comprising a sub-substrate layer and at least one weakening structure arranged on the sub-substrate layer; wherein the weakening structure comprises a structure column and a structure arm, the structure arm is fixedly connected to the sub-substrate layer through the structure column, the structure arm is arranged in parallel with the sub-substrate layer and perpendicularly to the structure column, and in any extension direction of the sub-substrate layer, the width dimension of the structure arm is greater than the width dimension of the structure column;

[0026] at least one light emitting device, each of the light emitting devices is arranged on the structure arm of the weakening structure.

[0027] In one of the embodiments, the substrate comprises a plurality of weakening structures arranged in an array, and each of the weakening structures is arranged in a spaced manner.

[0028] In one of the embodiments, the thickness dimension of the structure arm in the thickness direction of the light emitting device is 300 microns-500 microns.

[0029] In one of the embodiments, the thickness dimension of the structure column in the thickness direction of the light emitting device is greater than the thickness dimension of the structure arm, and the thickness dimension of the structure column is 1 / 3 of the thickness of the light emitting device.

[0030] The weakened structure of the light emitting device includes a substrate and at least one light emitting device. The substrate includes a sub-substrate layer, a structure column and a structure arm, and the light emitting device is arranged on the structure arm. The structure arm and the structure column form a T-shaped weakened structure, the substrate is thinned, the support for the light emitting device is realized with a smaller area, the transfer of the light emitting device is more convenient, the efficiency of the mass transfer is improved, and the cost of the mass transfer is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0032] Figure 1 A flowchart of a preparation method of a weakened structure of a light emitting device provided in an embodiment;

[0033] Figure 2a A cross-sectional structure diagram of a structure obtained in step S11 in a preparation method of a weakened structure of a light emitting device provided in an embodiment;

[0034] Figure 2b A cross-sectional structure diagram of a structure obtained in step S12 in a preparation method of a weakened structure of a light emitting device provided in an embodiment;

[0035] Figure 2c A cross-sectional structure diagram of a structure obtained in step S13 in a preparation method of a weakened structure of a light emitting device provided in an embodiment;

[0036] Figure 2d A cross-sectional structure diagram of a structure obtained in step S14 in a preparation method of a weakened structure of a light emitting device provided in an embodiment;

[0037] Figure 2e A cross-sectional structure diagram of a structure obtained in step S15 in a preparation method of a weakened structure of a light emitting device provided in an embodiment;

[0038] Figure 2f A cross-sectional structure diagram of a structure obtained in step S16 in a preparation method of a weakened structure of a light emitting device provided in an embodiment;

[0039] Figure 2g A cross-sectional structure diagram of a structure obtained in step S16 in a preparation method of a weakened structure of a light emitting device provided in another embodiment;

[0040] Figure 2hA cross-sectional view of the structure obtained in step S17 in the method for preparing a weakened structure of a light emitting device provided in an embodiment;

[0041] Figure 2i A cross-sectional view of the structure obtained in step S18 in the method for preparing a weakened structure of a light emitting device provided in an embodiment;

[0042] Figure 3 A top view of a light emitting device provided in an embodiment on a substrate;

[0043] Figure 4 A flow chart of a method for forming a protective layer on a light emitting device provided in an embodiment;

[0044] Figure 5 A cross-sectional view of the structure obtained in step S121 in the method for preparing a weakened structure of a light emitting device provided in an embodiment;

[0045] Figure 6a A top view of a patterned protective layer provided in an embodiment;

[0046] Figure 6b A top view of a patterned mask layer provided in an embodiment.

[0047] Explanation of reference numerals:

[0048] 10 - substrate, 110 - device region, 120 - non-device region, 130 - light emitting device, 140 - structure arm, 150 - sub-substrate, 151 - intermediate layer, 151a - structure column, 152 - sub-substrate layer, 20 - protective layer, 30 - mask layer. DETAILED DESCRIPTION

[0049] In order to facilitate the understanding of the present application, the present application will be described in more detail below with reference to the relevant drawings. The drawings show embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0051] It will be understood that when an element or layer is referred to as being "on", "adjacent", "connected" or "coupled" to another element or layer, it can be directly on, adjacent, connected or coupled to the other element or layer or intervening elements or layers can be present. In contrast, when an element is referred to as being "directly on", "directly adjacent", "directly connected" or "directly coupled" to another element or layer, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section; for example, a first doped type could be termed a second doped type; and similarly, a second doped type could be termed a first doped type; a first doped type and a second doped type are different doped types, e.g., a first doped type can be P-type and a second doped type can be N-type, or a first doped type can be N-type and a second doped type can be P-type.

[0052] Spatially relative terms, such as "beneath", "below", "lower", "under", "above", "upper" and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and / or operation in addition to the orientations depicted in the figures. For example, if a device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device can also be oriented in the other direction (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0053] The singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. It will be further understood that the terms "comprises", "comprising", "includes" and / or "including", or the like, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

[0054] Embodiments of the application are described herein with reference to the drawings, which show ideal embodiments (and intermediate structures) of the application. Variations can be made to the shapes of the elements shown because of such factors as manufacturing techniques and / or tolerances, and therefore other embodiments of the application should not be construed as limited to the particular shapes of elements shown. For example, an implanted region that is shown as a rectangle typically has rounded or curved features at its edges and / or an implant concentration gradient rather than a binary change from the implanted region to the non-implanted region. Also, a buried region formed by implantation can result in some implantation in the region between the buried region and the surface through which the implant was made. Therefore, the regions shown in the drawings are schematic only and their shapes are not intended to represent the actual shape of a region of a device, and are not intended to limit the scope of the application.

[0055] As mentioned in the background section, the micro LED bonding substrate is thick, which affects the efficiency of mass transfer. For this purpose, the present application provides a weakening structure of a light emitting device and a preparation method of the weakening structure of the light emitting device.

[0056] In one embodiment, a preparation method of a weakening structure of a light emitting device is provided. As shown in Figure 1 The preparation method of the weakening structure of the light emitting device can include the following steps S11 to S18.

[0057] S11: providing a substrate 10.

[0058] Referring to Figure 2a The substrate 10 can be a silicon <111> substrate, wherein the substrate 10 includes a device region 110 and a non-device region 120, and the device region 110 is provided with a light emitting device 130. The device region 110 is a region of the substrate 10 provided with the light emitting device 130, and the non-device region 120 is a region of the substrate 10 without the light emitting device 130. In other words, the projection region of the light emitting device 130 on the substrate 10 is the device region 110, and the region outside the projection of the light emitting device 130 on the substrate 10 is the non-device region 120. The light emitting device 130 can be any device with light emitting performance, for example, it can be a light emitting diode chip (LED), a mini LED chip (Mini LED), a micro LED chip (Micro LED), etc., which is not limited herein. The size of the light emitting device 130 can be set according to the demand of the light emitting device to be transferred, for example, the size of the light emitting device 130 can be 1-500 μm, and the present application is not limited to the size range of the light emitting device 130. The number of light emitting devices 130 can be one or more, which can be set according to actual needs, which is not limited herein.

[0059] S12: forming a protective layer 20 on the light emitting device 130.

[0060] Referring to Figure 2b The protective layer 20 is used to protect the light emitting device 130 from subsequent etching. The material of the protective layer 20 can be any suitable material, for example, photoresist, etc., which is not limited herein.

[0061] S13: Etching the substrate 10 in the non-device region 120 based on the protective layer 20.

[0062] Referring to Figure 2c The first etching refers to etching the substrate 10 in the non-device region 120 to remove part of the substrate 10 in the non-device region 120, thereby achieving the purpose of thinning the substrate 10. The direction of the first etching is perpendicular to the substrate 10. After the first etching, the structure arm 140 and the sub-substrate 150 are formed, in which Figure 2c The film layer in region A is the structure arm 140, and the film layer in region B is the sub-substrate 150. The structure arm 140 is fixedly connected with the sub-substrate 150, and the light emitting device 130 is arranged on the structure arm 140. The number of the structure arm 140 corresponds to the number of the light emitting device 130.

[0063] S14: Removing the protective layer 20.

[0064] Referring to Figure 2d The removal of the protective layer 20 can reduce the influence of the protective layer 20 on the subsequent process. For example, the material of the protective layer 20 is photoresist, and the protective layer 20 can be removed by a glue solution. In actual application, the material of the protective layer 20 can be removed according to the material of the protective layer 20, which is not limited herein.

[0065] S15: Forming a mask layer 30 on the substrate 10 and the light emitting device 130 after the first etching.

[0066] Referring to Figure 2e The mask layer 30 is located on the light emitting device 130 and the sub-substrate 150 formed after the first etching, and is also located on the sidewall of the structure arm 140 and the light emitting device 130 formed after the first etching, or in other words, the mask layer 30 is adjacent to the structure arm 140 and the light emitting device 130 formed after the first etching. The mask layer 30 is used to protect the light emitting device 130 from subsequent second etching, and is also used to control the area of the substrate 10 subjected to the second etching. The material of the mask layer 30 can be any suitable material, for example, photoresist, etc., which is not limited herein.

[0067] S16: Second etching the substrate 10 in the non-device region 120 based on the patterned mask layer 30.

[0068] Referring to Figure 2f, the patterned mask layer 30 is located on the sidewall of the sub-substrate 140 formed after the first etching, the sidewall of the light emitting device 130 and the upper surface of the light emitting device 130. The second etching refers to etching the substrate 10 in the non-device region 120 based on the patterned mask layer 30, specifically, etching the region (such as regions C1-C4 shown in Figure 2f ) on the sub-substrate 150 without the structural arm 140 and the mask layer 30. The direction of the second etching is the same as that of the first etching, both of which are perpendicular to the substrate 10. After the second etching, the sub-substrate 150 forms an intermediate layer 151 and a sub-substrate layer 152, as shown in Figure 2g . Among them, in the direction parallel to the substrate 10, the etching width w2 of the second etching is smaller than the etching width w1 of the first etching, see Figure 2d .

[0069] S17: Anisotropic etching is performed on the device region 120 and the exposed substrate 10 to form a structural column 151a.

[0070] As can be seen from steps S15 and Figure 2g , the device region 110 and the exposed substrate 10 are the intermediate layer 151, based on which, anisotropic etching is performed on the intermediate layer 151, or in other words, anisotropic etching is performed on the intermediate layer 151 to form a structural column 151a, as shown in Figure 2h . Among them, the etching direction of the anisotropic etching is the direction parallel to the substrate 10, and is perpendicular to the direction of the first etching and the direction of the second etching.

[0071] The structural arm 140 is fixedly connected to the sub-substrate layer 152 through the structural column 151a, the structural arm 140 and the sub-substrate layer 152 are arranged in parallel, and are arranged perpendicularly to the structural column 151a, and in any extension direction of the sub-substrate layer 152, the width dimension w3 of the structural arm 140 is greater than the width dimension w4 of the structural column 151a, the structural arm 151a and the structural column 152 form a T-shaped structure, see Figure 2i .

[0072] S18: Remove the mask layer 30. See Figure 2i .

[0073] The preparation method of the weakened structure of the light emitting device provided in the above embodiment first provides a substrate 10 provided with a light emitting device 130, then forms a protective layer 20 on the light emitting device 130, and performs one-time etching on the substrate 10 in the non-device area 120 based on the protective layer 20 and removes the protective layer 20, so as to realize the first thinning of the substrate 10. Then, a mask layer 30 is formed on the substrate 10 and the light emitting device 130 after one-time etching, and then the substrate in the non-device area 120 is etched twice based on the patterned mask layer 30, and the substrate 10 in the device area 120 and exposed is etched anisotropically to form a structure column 151a, and the mask layer 30 is removed, so as to realize the second thinning of the substrate 10. In addition, the structure column 151a and the substrate 10 in the device area 110 after one-time etching, that is, the structure arm 140, constitute a T-shaped weakened structure, so that the light emitting device 130 on the T-shaped weakened structure can be selectively picked up by using a common transfer head, thereby improving the efficiency of the mass transfer of the light emitting device 130 and reducing the cost of the mass transfer of the light emitting device 130.

[0074] In one embodiment, in step S11, a plurality of light emitting devices 130 in an array can be arranged on the substrate 10, and the light emitting devices 130 are arranged at intervals, as shown in Figure 3 .

[0075] In one embodiment, as shown in Figure 4 , in step S12, the protective layer 20 is formed on the light emitting device 130, which can include the following steps S121 and S122.

[0076] S121: Forming a protective layer 20 on the substrate 10 and the light emitting device 130, as shown in Figure 5 . For example, the material of the protective layer 20 can be photoresist.

[0077] S122: The protective layer 20 is patterned to remove the protective layer 20 on the substrate 10 and retain the protective layer 20 on the light emitting device 130, as shown in Figure 2b . For example, the patterning can be specifically photoresist development.

[0078] The preparation method of the weakened structure of the light emitting device provided in the above embodiment forms the protective layer 20 on the light emitting device 130 after the patterning of the protective layer 20, so as to protect the light emitting device 130 from the subsequent etching and not to affect the etching of the non-device area 120 of the substrate 10.

[0079] In one embodiment, based on the above step S13, after one-time etching of the substrate 10, a sub-substrate 150 and a structure arm 140 are formed, wherein the sub-substrate 150 is provided with the structure arm 140, and the structure arm 140 is provided with the light emitting device 130, as shown inFigure 2c Or Figure 2d Then, at step S16, before the secondary etching of the substrate 10 in the non-device region 120 based on the patterned mask layer 30, the preparation method of the light-emitting device weakening structure can further include step S19: forming the patterned mask layer 30 by photoetching development, that is, patterning the mask layer 30. The patterned mask layer 30 is located on the sidewall of the structure arm 140, the sidewall of the light-emitting device 130, and the upper surface of the light-emitting device 130. See Figure 2f Based on this, the secondary etching of the substrate 10 in the non-device region 120 after the primary etching can be performed to achieve the secondary thinning of the substrate 10 and form the T-shaped weakening structure.

[0080] It should be noted that the projected area of the patterned mask layer 30 on the substrate 10 is greater than the projected area of the patterned protective layer 20 on the substrate 10 after the patterning, so that Figure 3 For example, the top view of the patterned protective layer 20 is shown in Figure 6a , and the top view of the patterned mask layer 30 is shown in Figure 6b .

[0081] In one embodiment, referring to Figure 2d , the etching depth d1 of the primary etching in the direction perpendicular to the substrate 10 can be 300 microns (μm) to 500 microns (μm), for example, it can be 350 μm, 395 μm, 456 μm, etc., or any other value between 300 μm and 500 μm, which can be set according to actual application requirements, and here is not limited in any way.

[0082] In one embodiment, the etching depth d2 of the secondary etching in the direction perpendicular to the substrate 10 is greater than the etching depth d1 of the primary etching, and the etching depth d2 of the secondary etching is 1 / 3 of the thickness of the light-emitting device 130. See Figure 2g Based on this, the T-shaped weakening structure is more reliable and can support the light-emitting device 130 with a small area.

[0083] In one embodiment, the substrate 10 is a silicon <111> substrate, and step S17, the anisotropic etching of the exposed substrate 10 in the device region 110, can include step S171: using potassium hydroxide (KOH) solution to perform anisotropic etching or anisotropic corrosion of the exposed substrate 10 in the device region 120. Based on this, the structure column 151a can be formed to form a T-shaped structure with the structure arm 140, thereby forming a T-shaped weakening structure, which is conducive to the mass transfer of the light-emitting device 130.

[0084] In one embodiment, the potassium hydroxide solution used in step S171 may contain potassium hydroxide at a weight percentage of 45%-60%, for example, 48%, 50%, 54%, etc., or any other value between 45% and 60%, without any limitation herein. Furthermore, the temperature range of the potassium hydroxide solution may be 40°C-60°C, for example, 45%, 50%, 55%, etc., or any other value between 40°C and 60°C, without any limitation herein.

[0085] It should be understood that although the steps in each flowchart are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in each flowchart may include multiple steps or stages, which are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps.

[0086] In one embodiment, a weakened structure for the light-emitting device is provided. For example... Figure 2i As shown, the weakening structure of the light-emitting device may include a substrate and at least one light-emitting device 130.

[0087] The substrate includes a sub-substrate layer 152 and at least one weakening structure disposed on the sub-substrate layer 152. The weakening structure includes a structural pillar 151a and a structural arm 140. The structural arm 140 is fixedly connected to the sub-substrate layer 152 via the structural pillar 151a. The structural arm 140 is arranged parallel to the sub-substrate layer 152 and perpendicular to the structural pillar 151a. In any extending direction of the sub-substrate layer 152, the width w3 of the structural arm 140 is greater than the width w4 of the structural pillar 151a. Each light-emitting device 130 is located on a structural arm 140 of a weakening structure.

[0088] The weakened structure of the light-emitting device provided in the above embodiments includes a substrate and at least one light-emitting device 130. The substrate includes a sub-substrate layer 15, structural pillars 151a, and structural arms 140, with the light-emitting device 130 disposed on the structural arms 140. Since the structural arms 140 and structural pillars 151a form a T-shaped weakened structure, the substrate is thinned, achieving support for the light-emitting device 130 with a smaller area, facilitating the transfer of the light-emitting device 130, thus improving the efficiency of mass transfer and reducing the cost of mass transfer.

[0089] In one embodiment, the substrate comprises a plurality of weakening structures arranged in an array, each weakening structure is spaced apart, see Figure 3

[0090] In one embodiment, referring to Figure 2d The thickness dimension d1 of the structural arm 140 in the thickness direction of the light emitting device 130 can be 300 microns (μm) to 500 microns (μm), for example, can be 350 μm, 395 μm, 456 μm, etc., or other arbitrary values between 300 μm and 500 μm, which can be set according to actual application requirements, and is not limited here.

[0091] In one embodiment, referring to Figure 2g The thickness dimension d2 of the structural column 151a in the thickness direction of the light emitting device 130 is greater than the thickness dimension d1 of the structural arm 140, and the thickness dimension d2 of the structural column 151a is 1 / 3 of the thickness of the light emitting device 130. Based on this, the T-shaped weakening structure is more reliable, and can support the light emitting device 130 with a small part of the area.

[0092] In the description of the present specification, the description referring to the terms "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0093] The technical features of the above-described embodiments can be combined in any manner. In order to make the description concise, all possible combinations of the technical features of the above-described embodiments are not described, however, as long as the combination of the technical features does not exist Contradiction, it should be considered as the scope of the present application.

[0094] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent application scope. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.​

Claims

1. A method for fabricating a weakened structure for a light-emitting device, characterized in that, include: A substrate is provided, the substrate including a device region and a non-device region; wherein a light-emitting device is disposed on the device region; the substrate is silicon. <111> Substrate; A protective layer is formed on the light-emitting device; Based on the protective layer, the substrate in the non-device region is etched once; after the substrate is etched once, a structural arm and a sub-substrate are formed; the structural arm is located between the sub-substrate and the light-emitting device. Remove the protective layer; A mask layer is formed on the substrate after the first etching and on the light-emitting device; A secondary etching process is performed on the substrate in the non-device region based on a patterned mask layer. The etching width of the secondary etching is smaller than the etching width of the primary etching in the direction parallel to the substrate. The patterned mask layer is located on the sidewalls of the sub-substrate, the sidewalls of the light-emitting device, and the upper surface of the light-emitting device. The sub-substrate is etched twice to form an intermediate layer and a sub-substrate layer. The directions of the secondary etching and the primary etching are both perpendicular to the substrate. The etching width of the primary etching is the spacing between two adjacent sub-substrates. The etching width of the secondary etching is the spacing between two adjacent intermediate layers. Anisotropic etching is performed on the exposed substrate in the device region to form structural pillars; the exposed substrate in the device region is the intermediate layer; the structural arms and the structural pillars form a T-shaped weakening structure; Remove the mask layer.

2. The method for preparing the weakened structure of the light-emitting device according to claim 1, characterized in that, A sub-substrate and a structural arm are formed based on the first etching step; wherein the structural arm is disposed on the sub-substrate, and the light-emitting device is disposed on the structural arm; Before performing secondary etching on the substrate in the non-device region based on the patterned mask layer, the fabrication method of the light-emitting device weakening structure further includes: The patterned mask layer is formed by photolithography, and the patterned mask layer is located on the sidewall of the structural arm, the sidewall of the light-emitting device, and the upper surface of the light-emitting device.

3. The method for preparing the weakened structure of the light-emitting device according to claim 1, characterized in that, In the direction perpendicular to the substrate, the etching depth of the first etching is 300 micrometers to 500 micrometers.

4. The method for preparing the weakened structure of the light-emitting device according to claim 1, characterized in that, In the direction perpendicular to the substrate, the etching depth of the secondary etching is greater than the etching depth of the primary etching, and the etching depth of the secondary etching is 1 / 3 of the thickness of the light-emitting device.

5. The method for preparing the weakened structure of the light-emitting device according to claim 1, characterized in that, The anisotropic etching of the exposed substrate in the device region includes: Anisotropic etching is performed on the exposed substrate of the device area using a potassium hydroxide solution.

6. The method for preparing the weakened structure of the light-emitting device according to claim 5, characterized in that, The potassium hydroxide solution contains 45%-60% potassium hydroxide by weight, and the temperature range of the potassium hydroxide solution is 40℃-60℃.

7. A weakening structure for a light-emitting device, characterized in that, include: A substrate includes a sub-substrate layer and at least one weakening structure disposed on the sub-substrate layer; wherein the weakening structure includes a structural pillar and a structural arm, the structural arm is fixedly connected to the sub-substrate layer through the structural pillar, the structural arm is disposed parallel to the sub-substrate layer and perpendicular to the structural pillar, and in any extending direction of the sub-substrate layer, the width of the structural arm is greater than the width of the structural pillar. At least one light-emitting device, each of the light-emitting devices being located on a structural arm of one of the weakened structures; the weakened structure of the light-emitting device is obtained by the method for preparing the weakened structure of the light-emitting device as described in any one of claims 1-6.

8. The weakening structure of the light-emitting device according to claim 7, characterized in that, The substrate includes a plurality of weakening structures arranged in an array, with each weakening structure spaced apart.

9. The weakening structure of the light-emitting device according to claim 7, characterized in that, The thickness of the structural arm in the thickness direction of the light-emitting device is 300-500 micrometers.

10. The weakening structure of the light-emitting device according to claim 7, characterized in that, The thickness of the structural column in the thickness direction of the light-emitting device is greater than the thickness of the structural arm, and the thickness of the structural column is 1 / 3 of the thickness of the light-emitting device.

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