Light emitting diode wafer and preparation method thereof
By using spray etching and stretching technology to form multiple chip parts and connecting parts on the substrate, the problems of thermal damage and dimensional errors in existing cutting methods are solved, and efficient and low-damage light-emitting diode chip preparation is achieved, thereby improving product quality and output.
Patent Information
- Application Number
- CN202410713875.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-03-11
- Filing Date
- 2024-06-04
- Publication Date
- 2025-09-16
AI Technical Summary
Existing methods for cutting light-emitting diode wafers suffer from slow cutting speeds, severe thermal damage, and dimensional errors, particularly when cutting thin metal substrates or composite metal substrates, which impact the wafer's lifespan and productivity.
Spray etching and stretching technology is used to form a post-etching structure on a substrate to form multiple chip parts and connecting parts, which are patterned using a photoresist layer and a mask. After etching, the connecting parts are stretched on an elastic film to separate the chips, avoiding direct cutting and reducing thermal damage and dimensional errors.
It significantly reduces thermal damage and dimensional errors during the cutting process, improves the cutting efficiency and yield of LED wafers, and enhances product quality and output.
Smart Images
Figure CN120659458A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a light-emitting diode chip and a method for preparing the same, and more particularly to a light-emitting diode chip that is divided by structural expansion and a method for preparing the same. Background Art
[0002] The current method for preparing LED chips involves epitaxy on a substrate to create the initial diode structure. The substrate is then cut to separate the individual LED chips. There are three main cutting methods: laser cutting, knife cutting, and plasma cutting. Simply put, laser cutting and plasma cutting utilize high-powered lasers and thermal plasma, respectively, to melt the substrate, creating notches and fractures. Knife cutting, on the other hand, utilizes a sharp blade to separate the substrate.
[0003] The common drawbacks of laser cutting, knife cutting, and plasma cutting are their slow cutting speeds and the high temperatures generated during the cutting process, which can damage the LED wafers and, in turn, reduce their service life. Furthermore, when cutting thin metal substrates or composite metal substrates, laser cutting, knife cutting, and plasma cutting are prone to dimensional errors, further reducing the yield of LED wafers.
[0004] In view of this, how to improve the shortcomings of cutting light emitting diode chips has become the goal of relevant industries. Summary of the Invention
[0005] The present disclosure aims to provide a method for preparing a light emitting diode wafer, which can reduce thermal damage during cutting and improve cutting efficiency and yield.
[0006] One embodiment of the present disclosure provides a method for preparing a light-emitting diode chip, which includes the following steps: arranging a plurality of light-emitting diode elements on a surface of a substrate, wherein the light-emitting diode elements are spaced apart from each other by a distance. Making a photoresist layer cover the light-emitting diode elements and the surface of the substrate. Patterning the photoresist layer using a mask to form a structure to be etched. Spray etching the structure to be etched, and then removing the photoresist layer to form an etched structure, wherein the etched structure has a plurality of chip parts and a plurality of connecting parts, the connecting parts are respectively located between two adjacent chip parts and connect the two chip parts, and the light-emitting diode elements are respectively located in the chip parts. Transferring the etched structure to an elastic film. Stretching the elastic film to break the connecting parts to form a plurality of light-emitting diode chips.
[0007] According to the aforementioned method for preparing a light emitting diode chip, the substrate may be a composite metal substrate, and the composite metal substrate may include at least two structural layers.
[0008] According to the aforementioned method for preparing a light emitting diode chip, the material of each structural layer may include at least one of copper, nickel, and iron.
[0009] According to the aforementioned method for preparing a light emitting diode wafer, during the spray etching, a micro nozzle may be used to spray an etching liquid onto the structure to be etched.
[0010] According to the aforementioned method for preparing a light emitting diode chip, each connecting portion has a width, each chip portion has an edge length, and a ratio of the width to the edge length may be 0.1 to 0.2.
[0011] Another embodiment of the present disclosure provides a light-emitting diode chip, which is prepared by the above-mentioned method for preparing a light-emitting diode chip. The substrate of the light-emitting diode chip has a body and at least one protrusion, wherein the protrusion is connected to the body and extends outward from the body.
[0012] According to the aforementioned light emitting diode chip, the number of the protrusions may be two, the body may be in a quadrilateral shape, and the two protrusions may be respectively connected to two adjacent edges of the body.
[0013] According to the aforementioned light emitting diode chip, the number of the protrusions may be three, the body may be in a quadrilateral shape, and the three protrusions may be respectively connected to three adjacent edges of the body.
[0014] According to the aforementioned light emitting diode chip, the number of the protrusions may be four, the body may be in a quadrilateral shape, and the four protrusions may be connected to four edges of the body respectively.
[0015] According to the aforementioned light emitting diode chip, the protrusion may be in a trapezoidal shape, and a longer bottom side of the protrusion may be connected to the body.
[0016] Accordingly, the method for preparing an LED wafer of the present disclosure adjusts the post-etching structure so that the post-etching structure has multiple wafer portions and multiple connection portions. The wafer portions can then be separated by stretching, thereby significantly reducing structural damage, thermal damage, or dimensional errors caused by conventional cutting, and improving the efficiency of manufacturing LED wafers. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] To make the above and other objects, features, advantages and embodiments of the present disclosure more apparent, the accompanying drawings are described as follows:
[0018] Figure 1 This is a flow chart of the steps of a method for preparing a light-emitting diode wafer according to one embodiment of the present disclosure;
[0019] Figure 2 、 Figure 3 、 Figure 4 、 Figure 5A 、 Figure 5B 、 Figure 6 、 Figure 7A and Figure 7B are structural schematic diagrams of each step in the method for preparing a light emitting diode wafer; and
[0020] Figure 8 Schematic diagram of the structure of a light-emitting diode chip.
[0021] Explanation of symbols
[0022] 100: Method for preparing light-emitting diode wafer
[0023] 110,120,130,140,150,160: Steps
[0024] 210,310: Light-emitting diode components
[0025] 220,320:Substrate
[0026] 230: Photoresist layer
[0027] 240: Tether
[0028] 250: Elastic membrane
[0029] 260: convex part
[0030] 300: Light-emitting diode chip
[0031] 321: Ontology
[0032] 322: convex part
[0033] M: Mask
[0034] M1: First light shielding part
[0035] M2: Second light shielding part
[0036] S1: structure to be etched
[0037] S2: Structure after etching
[0038] S21: Chip Department
[0039] S22: Connection
[0040] N: Micro nozzle
[0041] W: width
[0042] L: edge length
[0043] D1: first extension direction
[0044] D2: Second extension direction DETAILED DESCRIPTION
[0045] The following will discuss various embodiments of the present disclosure in more detail. However, these embodiments may be applications of various disclosed concepts and may be implemented within a variety of specific scopes. The specific embodiments are provided for illustrative purposes only and are not intended to limit the scope of the disclosure. Furthermore, to simplify the drawings, some conventional structures and elements may be shown in simplified schematic form, and duplicate elements may be represented using the same or similar numbers.
[0046] Please refer to Figure 1 , Figure 1 FIG1 is a flow chart of a method 100 for fabricating a light emitting diode wafer according to an embodiment of the present disclosure. The method 100 for fabricating a light emitting diode wafer includes steps 110 , 120 , 130 , 140 , 150 , and 160 .
[0047] Please refer to Figure 2 , Figure 2 The figure is a schematic diagram of step 110 in method 100 for fabricating an LED wafer. Step 110 involves disposing a plurality of LED elements 210 on a surface of a substrate 220, with the LED elements 210 spaced apart to maintain adequate spacing for subsequent separation. Substrate 220 can be a composite metal substrate comprising at least two structural layers, each of which can be made of at least one of copper, nickel, and iron. For example, the composite metal substrate can have a multilayer structure, and the material of each layer can be adjusted based on physical and chemical properties or circuit requirements, and is not limited by the present disclosure.
[0048] Please refer to Figure 3 , Figure 3 FIG1 is a schematic diagram illustrating step 120 of method 100 for fabricating an LED wafer. Step 120 involves coating the surfaces of LED element 210 and substrate 220 with a photoresist layer 230. Photoresist layer 230 can be made of either a positive-type or negative-type photoresist. While this disclosure will be described using a positive-type photoresist as an example, the disclosure is not limited thereto.
[0049] Please refer to Figure 4 , Figure 4FIG1 is a schematic diagram of step 130 in method 100 for fabricating an LED wafer. Step 130 involves patterning the photoresist layer 230 using a mask M to form a structure S1 to be etched. Specifically, the mask M may have a plurality of first light-shielding portions M1 and a plurality of second light-shielding portions M2. During patterning, the first light-shielding portions M1 may be positioned relative to the LED elements 210. The first light-shielding portions M1 may be slightly larger than the LED elements 210, and the second light-shielding portions M2 may be positioned between and connect two adjacent first light-shielding portions M1.
[0050] Please refer to Figure 5A and Figure 5B , Figure 5A FIG1 is a structural diagram of step 140 in the method 100 for preparing a light-emitting diode wafer. Figure 5B FIG1 is another structural diagram of step 140 in the method 100 for preparing a light-emitting diode chip. Step 140 is to spray-etch the structure to be etched S1 and then remove the photoresist layer 230 to form an etched structure S2. When performing spray etching, a micro nozzle N can be used to spray an etching liquid onto the structure to be etched S1, thereby removing the substrate 220 not covered by the mask M and the portion of the substrate 220 covered by the second light-shielding portion M2, so as to form a structure S2 as shown in FIG1. Figure 5A The mesh structure shown.
[0051] In detail, since the substrate 220 can be a composite metal substrate and can include at least two structural layers, preferably two to five structural layers, a suitable etching selectivity can be obtained during spray etching, that is, the etching solution can cause different etching rates for different structural layers, thereby leaving behind the structural layer close to the mask M. In addition, spray etching can also reduce the side etching of the substrate 220, thus helping to form a similar Figure 5A The mesh structure shown.
[0052] The etched structure S2 comprises a plurality of chip portions S21 and a plurality of connecting portions S22. The connecting portions S22 are respectively located between two adjacent chip portions S21 and connect the two chip portions S21. The light emitting diode elements 210 are respectively located in the chip portions S21. Figure 5B It can be seen that when the portion of the substrate 220 covered by the second light shielding portion M2 is removed, a plurality of thinner tethers 240 are formed, and the tethers 240 respectively belong to the connecting portion S22 .
[0053] Furthermore, each connecting portion S22 has a width W, each wafer portion S21 has an edge length L, and the ratio of the width W to the edge length L can be 0.1 to 0.2. This increases the connection strength between the wafer portions S21 and improves the efficiency of subsequent separation of the wafer portions S21. The etched structure S2 only needs to have the wafer portions S21 and the connecting portions S22 to be successfully separated in subsequent steps. Therefore, the present disclosure is not limited to the dimensions of the wafer portions S21 and the connecting portions S22.
[0054] Please refer to Figure 6 , Figure 6 FIG. 1 is a schematic diagram of the structure of step 150 in the method 100 for preparing a light emitting diode chip. Step 150 is to transfer the etched structure S2 onto an elastic film 250 to facilitate the subsequent separation of the chip portion S21.
[0055] Please refer to Figure 7A and Figure 7B , Figure 7A FIG. 1 is a structural diagram of step 160 in the method 100 for preparing a light-emitting diode wafer. Figure 7B FIG2 is another schematic diagram of step 160 in method 100 for fabricating LED chips. Step 160 involves stretching the elastic film 250, breaking the connecting portion S22 to form a plurality of LED chips (not numbered). Upon breaking of the connecting portion S22, a protrusion 260 is formed on each edge of the two chip portions S21 connected to the connecting portion S22. Furthermore, each connecting portion S22 has an extension direction, exemplified herein by a first extension direction D1 and a second extension direction D2. When the elastic film 250 is stretched, the stretching can proceed parallel to the first and second extension directions D1 and D2. Furthermore, the center of each connecting portion S22 can be thinner than the ends connected to the chip portion S21 to control the breaking point of the connecting portion S22 and reduce the possibility of damage to the chip portion S21 due to breaking of the connecting portion S22.
[0056] It should be noted that although Figures 2 to 7B Only nine LED chips are prepared as an example. In actual production, the number of LED elements 210 and the area of substrate 220 can be increased, and the shape of mask M can be adjusted accordingly to prepare a large number of LED chips. Figures 2 to 7B The quantities or configurations shown are limited.
[0057] Please refer to Figure 8 , Figure 8FIG3 is a schematic diagram of the structure of an LED chip 300. Another embodiment of the present disclosure provides an LED chip 300 fabricated using the aforementioned LED chip fabrication method 100. The substrate 320 of the LED chip 300 comprises a body 321 and at least one protrusion 322. The protrusion 322 is connected to the body 321 and extends outward from the body 321. The LED element 310 of the LED chip 300 is located on the body 321.
[0058] In detail, since the connection portion S22 between two adjacent wafer portions S21 will break when the wafer portions S21 are separated from each other, leaving the convex portion 322, the number of the convex portions 322 can be four, the main body 321 can be a quadrilateral, and the four convex portions 322 can be connected to the four edges of the main body 321 respectively. Alternatively, please refer to Figure 7A , the wafer portion S21 located at the corner of the etched structure S2 is connected to only two connecting portions S22, so the number of protrusions 322 can be two, and the two protrusions 322 can be respectively connected to two adjacent edges of the body 321. Alternatively, the wafer portion S21 located at the edge of the etched structure S2 is only connected to three connecting portions S22, so the number of protrusions 322 can be three, and the three protrusions 322 can be respectively connected to three adjacent edges of the body 321.
[0059] Furthermore, since the center of the connecting portion S22 can be thinner than the two ends connected to the chip portion S21 , the broken protrusion 322 can be trapezoidal, and a longer bottom side of the protrusion 322 can be connected to the body 321 .
[0060] In summary, the method for preparing an LED wafer of the present disclosure adjusts the post-etching structure to include multiple wafer portions and multiple connection portions. The wafer portions can then be separated by stretching. This significantly reduces structural damage, thermal damage, or dimensional errors caused by conventional cutting, and improves the efficiency of manufacturing LED wafers.
[0061] Although the present disclosure has been disclosed above in the form of embodiments, it is not intended to limit the present disclosure. Any person skilled in the art may make various changes and modifications without departing from the concept and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be determined by the claims.
Claims
1. A method for preparing a light emitting diode wafer, characterized in that: Include: Disposing a plurality of light-emitting diode elements on a surface of a substrate, wherein the plurality of light-emitting diode elements are spaced apart from each other by a distance; Making a photoresist layer cover the plurality of light-emitting diode elements and the surface of the substrate; patterning the photoresist layer using a mask to form a structure to be etched; Performing spray etching on the structure to be etched, and then removing the photoresist layer to form an etched structure, wherein the etched structure has a plurality of chip portions and a plurality of connecting portions, wherein the plurality of connecting portions are respectively located between two adjacent chip portions and connect the two chip portions, and the plurality of light-emitting diode elements are respectively located on the plurality of chip portions; transferring the etched structure onto an elastic film; as well as The elastic film is stretched to break the plurality of connection portions to form a plurality of light emitting diode chips.
2. The method for preparing a light emitting diode wafer according to claim 1, wherein: The substrate is a composite metal substrate, and the composite metal substrate includes at least two structural layers.
3. The method for preparing a light emitting diode wafer according to claim 2, wherein: The material of the at least two structural layers includes at least one of copper, nickel and iron.
4. The method for preparing a light emitting diode wafer according to claim 1, wherein: During spray etching, an etching liquid is sprayed onto the structure to be etched using a micro nozzle.
5. The method for preparing a light emitting diode wafer according to claim 1, wherein: Each connecting portion has a width, each chip portion has an edge length, and a ratio of the width to the edge length is 0.1 to 0.
2.
6. A light-emitting diode chip, characterized in that: The light-emitting diode chip is prepared by the method for preparing a light-emitting diode chip as claimed in claim 1; The substrate of the light emitting diode chip has a body and at least one protrusion, and the at least one protrusion is connected to the body and extends outward from the body.
7. The light-emitting diode chip according to claim 6, wherein: The number of the at least one convex portion is two, the main body is in a quadrilateral, and the two convex portions are respectively connected to two adjacent edges of the main body.
8. The light-emitting diode chip according to claim 6, wherein: The number of the at least one convex portion is three, the main body is in a quadrilateral, and the three convex portions are respectively connected to three adjacent edges of the main body.
9. The light-emitting diode chip according to claim 6, wherein: The number of the at least one convex portion is four, the main body is in a quadrilateral, and the four convex portions are respectively connected to the four edges of the main body.
10. The light emitting diode chip according to claim 6, wherein The at least one protrusion is in a trapezoidal shape, and a longer bottom side of the at least one protrusion is connected to the main body.