Light-emitting device and preparation method thereof

Abstract

The invention provides a light-emitting device and a preparation method of the light-emitting device. The light-emitting device comprises a substrate, an adhesive layer and at least one light-emitting diode chip, the adhesive layer is located on one side of the substrate, the light-emitting diode chip is connected with the substrate through the adhesive layer, and the thickness of the substrate is 5-50 microns. The thickness of the substrate used by the light-emitting device provided by the embodiment of the invention is smaller than that of the substrate in the related technology, the light-emitting efficiency of the light-emitting device can be improved, the light-emitting diode chip is connected with the surface of the substrate through the adhesive layer, the substrate is not easy to break due to the viscidity of the adhesive layer, and the yield of the light-emitting device is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of light-emitting devices, and particularly to a light-emitting device and a method for manufacturing the same. Background Art

[0002] The applications of light-emitting diodes (LEDs) have expanded from indicator lights to multiple fields such as display screens, signal lights, lighting, and medical devices.

[0003] Related technologies provide a light-emitting device, including: a substrate and a light-emitting diode chip, and the light-emitting diode chip is located on the substrate.

[0004] Currently, the light-emitting device with the above structure has the problem of relatively low light extraction efficiency. Summary of the Invention

[0005] Embodiments of the present disclosure provide a light-emitting device and a method for manufacturing the same, and the manufactured substrate is thinner, which can improve the light extraction efficiency. The technical solution is as follows:

[0006] On the one hand, a light-emitting device is provided, and the light-emitting device includes:

[0007] a substrate, an adhesive layer, and at least one light-emitting diode chip;

[0008] The adhesive layer is located on one side of the substrate, the light-emitting diode chip is connected to the substrate through the adhesive layer, and the thickness of the substrate is 5 - 50 μm.

[0009] Optionally, the surface of the substrate away from the light-emitting diode chip is a roughened surface;

[0010] The roughening depth of the roughened surface is 0.2 - 2 μm;

[0011] The particle diameter of the roughened surface is 0.1 - 1.5 μm.

[0012] Optionally, the light-emitting device further includes: an antireflection film;

[0013] The antireflection film is located on the roughened surface of the substrate, and the refractive index of the antireflection film is less than the refractive index of the substrate.

[0014] Optionally, the light-emitting device further includes a light absorption layer, a connection electrode layer, an insulating layer, and four electrode pads;

[0015] The light absorption layer wraps the light-emitting diode chip; the connection electrode layer is located on the side of the surface of the light absorption layer away from the light-emitting diode chip and is electrically connected to the light-emitting diode chip; the insulating layer wraps the connection electrode layer; the four electrode pads are located on the side of the surface of the insulating layer away from the connection electrode layer and are electrically connected to the connection electrode layer.

[0016] On the other hand, a method for manufacturing a light-emitting device is provided, and the method includes:

[0017] Fabricating a composite substrate, the composite substrate includes a first substrate, a second adhesive layer, and a second substrate, and the first substrate and the second substrate are connected by the second adhesive layer;

[0018] Thinning the first substrate, and fabricating a first adhesive layer on the surface of the first substrate away from the second substrate, and the thickness of the thinned first substrate is 5 - 50 μm;

[0019] Transferring a plurality of light-emitting diode chips to the side of the first substrate having the first adhesive layer;

[0020] Removing the second substrate and the second adhesive layer;

[0021] Cutting the first substrate to form the light-emitting device.

[0022] Optionally, the thickness of the first substrate before thinning is 200 - 700 μm;

[0023] The thickness of the second substrate is 200 - 700 μm.

[0024] Optionally, the method further includes:

[0025] Before fabricating the composite substrate, roughening the first substrate to form a roughened surface;

[0026] The roughening depth of the roughened surface is 0.2 - 2 μm;

[0027] The particle diameter of the roughened surface is 0.1 - 1.5 μm.

[0028] Optionally, roughening the surface of the composite substrate includes:

[0029] Under the condition that the temperature is 200 - 500 °C, using sulfuric acid or a mixed solution of sulfuric acid and phosphoric acid to corrode the side of the first substrate in the composite substrate away from the second substrate, and the corrosion time is 0.5 - 10 h to form the roughened surface;

[0030] The ratio of the sulfuric acid and phosphoric acid mixed solution is 1:0.2 to 1:5.

[0031] Optionally, the method further includes:

[0032] Fabricating an antireflection film on a surface of the first substrate away from the first adhesive layer, where the refractive index of the antireflection film is less than that of the first substrate.

[0033] Optionally, the method further includes:

[0034] Performing patterning on the first adhesive layer to remove the first adhesive layer between the plurality of light-emitting diode chips.

[0035] The beneficial effects brought by the technical solution provided by the embodiments of the present disclosure are:

[0036] In the embodiments of the present disclosure, the light-emitting device includes a substrate, an adhesive layer, and at least one light-emitting diode chip. Among them, the thickness of the substrate is 5 to 50 μm. The substrate used in the light-emitting device provided by the embodiments of the present disclosure is thinner than the substrate in the related art, which can improve the light extraction efficiency of the light-emitting device. Moreover, the light-emitting diode chip is connected to the surface of the substrate through the adhesive layer. Due to the viscosity of the adhesive layer, the substrate is not easily broken, improving the yield of the light-emitting device. Description of the Drawings

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0038] Figure 1 is a structural diagram of a light-emitting device provided by an embodiment of the present disclosure;

[0039] Figure 2 is a structural diagram of another light-emitting device provided by an embodiment of the present disclosure;

[0040] Figure 3 is a flowchart of a method for manufacturing a light-emitting device provided by an embodiment of the present disclosure;

[0041] Figure 4 is a flowchart of a method for manufacturing a light-emitting device provided by an embodiment of the present disclosure;

[0042] Figure 5 is a structural diagram during the manufacturing process of a light-emitting device provided by an embodiment of the present disclosure;

[0043] Figure 6 is a structural diagram during the manufacturing process of a light-emitting device provided by an embodiment of the present disclosure;

[0044] Figure 7It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure;

[0045] Figure 8 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure;

[0046] Figure 9 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure;

[0047] Figure 10 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure;

[0048] Figure 11 It is a flowchart of a method for preparing a light-emitting device provided by an embodiment of the present disclosure;

[0049] Figure 12 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure;

[0050] Figure 13 It is a flowchart of a method for preparing a light-emitting device provided by an embodiment of the present disclosure;

[0051] Figure 14 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure.

[0052] The reference numerals are as follows:

[0053] 101: Substrate; 102: Adhesive layer; 103: Light-emitting diode chip; 104: Electrode structure layer; 105: Tape; 106: Antireflection film; 107: Second adhesive layer; 108: Second substrate;

[0054] 141: Light absorption layer; 142: Connecting electrode layer; 143: Insulating layer; 144: Four electrode pads;

[0055] 1011: Composite substrate;

[0056] 201: Roughened surface. Detailed implementation manners

[0057] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will further describe the embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0058] Figure 1 It is a structural diagram of a light-emitting device provided by an embodiment of the present disclosure; see Figure 1 , the light-emitting device includes:

[0059] Substrate 101, adhesive layer 102, and at least one light-emitting diode chip 103;

[0060] The glue layer 102 is located on one side of the substrate 101. The light-emitting diode chip 103 is connected to the substrate 101 through the glue layer 102. The thickness of the substrate 101 is 5 - 50 μm.

[0061] In the embodiment of the present disclosure, the light-emitting device includes a substrate, a glue layer, and at least one light-emitting diode chip. Among them, the thickness of the substrate is 5 - 50 μm. The substrate used in the light-emitting device provided by the embodiment of the present disclosure is thinner than the substrate in the related art, which can improve the light extraction efficiency of the light-emitting device. And the light-emitting diode chip is connected to the surface of the first substrate through the first glue layer. Due to the viscosity of the glue layer, the substrate is not easily broken, improving the yield of the light-emitting device.

[0062] In the embodiment of the present disclosure, the surface of the substrate 101 away from the light-emitting diode chip 103 is a roughened surface 201. The roughened surface can increase the escape ratio of photons on the roughened surface, improve the light extraction efficiency, and thus improve the brightness of the light-emitting device.

[0063] In the embodiment of the present disclosure, the roughening depth of the roughened surface 201 can be 0.2 - 2 μm. On the one hand, this depth can ensure a sufficient depth to improve the light extraction efficiency. On the other hand, the substrate with the roughened surface of this depth can support the light-emitting diode chip.

[0064] Exemplarily, the roughening depth of the roughened surface 201 is 1 μm.

[0065] In the embodiment of the present disclosure, the particle diameter of the roughened surface 201 can be 0.1 - 1.5 μm. This particle diameter can ensure the light-emitting efficiency and the substrate support effect.

[0066] Exemplarily, the particle diameter of the roughened surface 201 is 1 μm.

[0067] In the embodiment of the present disclosure, the light-emitting device further includes: an antireflection film 106.

[0068] The antireflection film 106 is located on the roughened surface 201 of the substrate 101. The refractive index of the antireflection film 106 is less than the refractive index of the first substrate 101.

[0069] In this implementation, the refractive index of the antireflection film is less than the refractive index of the substrate, so as to achieve an antireflection effect, improve the light transmittance, and thus improve the brightness of the light-emitting diode.

[0070] Figure 2 It is a structural diagram of another light-emitting device provided by the embodiment of the present disclosure. Compared with Figure 1 This light-emitting device further includes: an electrode structure layer 104.

[0071] The light-emitting device can be a pixel in a Micro LED in Package (MIP). In MIP, one pixel can include three light-emitting diode chips 103, such as red, green, and blue light-emitting diode chips.

[0072] The electrode structure layer 104 can include a light absorption layer 141, a connection electrode layer 142, an insulating layer 143, and four electrode pads 144.

[0073] The light absorption layer 141 wraps the light-emitting diode chip 103; the connection electrode layer 142 is located on the side of the surface of the light absorption layer 141 away from the light-emitting diode chip 103 and is electrically connected to the light-emitting diode chip 103; the insulating layer 143 wraps the connection electrode layer 142; the four electrode pads 144 are located on the side of the surface of the insulating layer 143 away from the connection electrode layer 142 and are electrically connected to the connection electrode layer 142.

[0074] In this implementation, the light absorption layer wraps the light-emitting diode chip, thereby improving the contrast of the MIP. The connection electrode layer is used to lead out the electrodes of the three light-emitting diode chips to form a common negative electrode and three independent positive electrodes, and the above electrodes are respectively connected to the four electrode pads (i.e., pads), thus facilitating bonding with the driving circuit.

[0075] It should be noted that Figure 2 Only the part of the connection electrode layer 142 that connects to the negative electrode of the light-emitting diode chip 103 to form a common negative electrode is shown, and only the electrode pad to which the common negative electrode is connected among the four electrode pads 144 is shown.

[0076] In the embodiments of the present disclosure, the glue layer 102 can be a polyimide, an acrylic resin, or a silicone-based adhesive layer. Using the above materials can provide excellent bonding performance and tightly connect the light-emitting diode chip and the substrate.

[0077] Exemplarily, the glue layer 102 is a polyimide layer.

[0078] In the embodiments of the present disclosure, the substrate 101 can be any one of substrates such as a sapphire substrate, an Si substrate, and an SiC substrate.

[0079] Exemplarily, the substrate 101 can be a sapphire substrate.

[0080] In the embodiments of the present disclosure, the wavelength range that the substrate 101 can pass through can be 200 - 400 nm.

[0081] In the embodiments of the present disclosure, each light-emitting device can include a light-emitting diode chip 103, which is connected to the surface of the substrate 101 through the glue layer 102.

[0082] In the embodiments of the present disclosure, each light-emitting device may also include three or more light-emitting diode chips 103. The light-emitting devices may be light-emitting diode chips with the same color or different colors, and the number or color of the light-emitting diodes depends on the driving method and pixel specifications of the display panel.

[0083] Exemplarily, each light-emitting device includes three light-emitting diode chips 103, which are a red light-emitting diode chip, a green light-emitting diode chip, and a blue light-emitting diode chip respectively. The three light-emitting diode chips 103 form a light-emitting device, and this light-emitting device can be used as a pixel of the display panel.

[0084] Figure 3 It is a flowchart of a method for manufacturing a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 3 The method steps include:

[0085] In the embodiments of the present disclosure, the first substrate is the above-mentioned substrate, and the first glue layer is the above-mentioned glue layer.

[0086] S11. Manufacture a composite substrate, which includes a first substrate, a second glue layer, and a second substrate. The first substrate and the second substrate are connected by the second glue layer.

[0087] S12. Thin the first substrate, and manufacture a first glue layer on the surface of the first substrate away from the second substrate. The thickness of the thinned first substrate is 5-50 μm.

[0088] S13. Transfer a plurality of light-emitting diode chips to the side of the first substrate with the first glue layer.

[0089] S14. Remove the second substrate and the second glue layer.

[0090] S15. Cut the first substrate to form the light-emitting device.

[0091] In the embodiments of the present disclosure, the light-emitting device includes a first substrate, a first glue layer, and a light-emitting diode chip. Among them, the thickness of the first substrate is 5-50 μm. The thickness of the substrate used in the light-emitting device provided by the embodiments of the present disclosure is thinner than that of the substrate in the related art, which can improve the light extraction efficiency of the light-emitting device. And the light-emitting diode chip is connected to the surface of the first substrate through the first glue layer. Due to the viscosity of the glue layer, the substrate is not easily broken, improving the yield of the light-emitting device.

[0092] Figure 4 It is a flowchart of a method for manufacturing a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 4 The method steps include:

[0093] S21. Fabricate a composite substrate, which includes a first substrate, a second adhesive layer, and a second substrate. The first substrate and the second substrate are connected by the second adhesive layer.

[0094] Figure 5 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 5 , the second substrate 108 and the substrate 101 are connected by the adhesive layer 107 to form a composite substrate 1011.

[0095] In one example, step S21 may include:

[0096] The first step is to fabricate the first substrate.

[0097] In the embodiment of the present disclosure, the first substrate may be any one of substrates such as a sapphire substrate, an Si substrate, and an SiC substrate.

[0098] Exemplarily, the first substrate may be a sapphire substrate.

[0099] In the embodiment of the present disclosure, the thickness of the first substrate may be 200 - 700 μm. The first substrate fabricated with the above thickness is not easily broken during transfer and has sufficient thickness during subsequent substrate thinning.

[0100] Exemplarily, the thickness of the first substrate may be 500 μm.

[0101] In the embodiment of the present disclosure, the transmissible wavelength range of the first substrate may be 200 - 400 nm. The above wavelength range allows red light, green light, and blue light to pass through.

[0102] In the embodiment of the present disclosure, the first step may include: performing double-sided polishing on the first substrate.

[0103] The second step is to fabricate the second substrate.

[0104] In the embodiment of the present disclosure, the second substrate may be any one of substrates such as a sapphire substrate, an Si substrate, and an SiC substrate.

[0105] Exemplarily, the second substrate may be a sapphire substrate.

[0106] In the embodiment of the present disclosure, the thickness of the second substrate may be 200 - 700 μm. The first substrate fabricated with the above thickness is not easily broken during transfer and is easily peeled off during subsequent fabrication processes.

[0107] Exemplarily, the thickness of the second substrate is 500 μm.

[0108] In the embodiments of the present disclosure, the wavelength range that the second substrate can pass through can be 200 - 400 nm. Adopting the above wavelength range can allow red light, green light, and blue light to pass through.

[0109] In the embodiments of the present disclosure, the second step may include: performing double-sided polishing on the second substrate.

[0110] The third step is to bond the first substrate and the second substrate through the second adhesive layer to form a composite substrate.

[0111] In the embodiments of the present disclosure, the second adhesive layer can be an adhesive layer made of polyimide (PI), acrylic resin, or silicone-based adhesive.

[0112] Exemplarily, the first adhesive layer can be an adhesive layer made of polyimide.

[0113] S22. Thin the first substrate, and form a first adhesive layer on the surface of the first substrate away from the second substrate. The thickness of the thinned first substrate is 5 - 50 μm.

[0114] Figure 6 It is a structural diagram in the preparation process of a light-emitting device provided by the embodiments of the present disclosure. Refer to Figure 6 , the substrate 101 is the thinned substrate 101 and is provided with an adhesive layer 102.

[0115] In one example, step S22 may include:

[0116] The first step is to thin the first substrate.

[0117] In the embodiments of the present disclosure, the thickness of the thinned first substrate can be 2 - 100 μm. For a light-emitting device with this thickness, it has a good light-emitting angle and can improve the light-emitting efficiency.

[0118] Exemplarily, the thickness of the thinned first substrate can be 50 μm.

[0119] The second step is to form a first adhesive layer on one side of the first substrate away from the second adhesive layer.

[0120] In the embodiments of the present disclosure, the first adhesive layer can be an adhesive layer made of polyimide, acrylic resin, or silicone-based adhesive. Using the above materials can provide excellent bonding performance and make the light-emitting diode and the substrate closely connected.

[0121] Exemplarily, the first adhesive layer can be an adhesive layer made of polyimide.

[0122] S23. Transfer a plurality of light-emitting diode chips to the side of the first substrate having the first adhesive layer.

[0123] Figure 7It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 7 , multiple light-emitting diode chips 103 are connected to the substrate 101 through an adhesive layer 102.

[0124] In an embodiment of the present disclosure, each light-emitting device may include a light-emitting diode chip, which is connected to the surface of the first substrate through a first adhesive layer.

[0125] In an embodiment of the present disclosure, each light-emitting device may also include 3 or more light-emitting diode chips. The light-emitting devices may be light-emitting diode chips with the same color or different colors. The specific number or color of the light-emitting diodes depends on the driving method and pixel specifications of the display panel.

[0126] Exemplarily, each light-emitting device includes 3 light-emitting diode chips, which are a red light-emitting diode chip, a green light-emitting diode chip, and a blue light-emitting diode chip respectively. The 3 light-emitting diode chips form a light-emitting device, and this light-emitting device can be used as a pixel of the display panel.

[0127] S24. Fabricate an electrode structure layer of the light-emitting diode chip.

[0128] This electrode structure layer is used to connect the negative electrodes of the three light-emitting diode chips to form a common negative electrode.

[0129] The positive electrodes of the three light-emitting diode chips are independent positive electrodes, which are respectively connected to the first substrate through the first adhesive layer.

[0130] Figure 8 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 8 , the electrode structure layer 104 covers and is connected to multiple light-emitting diode chips 103 through the adhesive layer 102.

[0131] In one example, the electrode structure layer may further include a light absorption layer, a connection electrode layer, an insulating layer, and four electrode pads.

[0132] The light absorption layer wraps the light-emitting diode chip; the connection electrode layer is located on the side of the surface of the light absorption layer away from the light-emitting diode chip and is electrically connected to the light-emitting diode chip; the insulating layer wraps the connection electrode layer; the four electrode pads are located on the side of the surface of the insulating layer away from the connection electrode layer and are electrically connected to the connection electrode layer.

[0133] In this implementation manner, the light absorption layer wraps the light-emitting diode chip, thereby improving the contrast of the MIP. The connection electrode layer is used to lead out the electrodes of the three light-emitting diode chips to form a common negative electrode and three independent positive electrodes, and the above electrodes are respectively connected to the four electrode pads (i.e., pads), so as to facilitate bonding with the driving circuit.

[0134] S25. Bond the side of the first substrate with the light-emitting diode chips to the tape.

[0135] Figure 9 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 9 , the electrode structure layer 104 is connected to the tape 105.

[0136] In the embodiment of the present disclosure, the tape can be a blue film or a UV film.

[0137] Exemplarily, the tape is a blue film.

[0138] S26. Remove the second substrate and the second adhesive layer.

[0139] Figure 10 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 10 , Figure 10 In Figure 9 Based on the shown structure, the second substrate 108 and the second adhesive layer 107 are removed.

[0140] In one example, step S26 may include:

[0141] The first step is to remove the second substrate.

[0142] In the embodiment of the present disclosure, the second substrate is removed by laser debonding.

[0143] The second step is to remove the second adhesive layer.

[0144] In the embodiment of the present disclosure, the second adhesive layer is removed using a degluing solution.

[0145] S27. Cut the first substrate to form the light-emitting device.

[0146] In one example, step S27 may include:

[0147] The first step is to scribe a channel.

[0148] In the embodiment of the present disclosure, the channel is scribed using a laser.

[0149] The second step is to separate the light-emitting device.

[0150] In the embodiment of the present disclosure, the light-emitting device is separated by expanding the tape.

[0151] After scribing, the individual light-emitting devices can be tested and sorted to pick out suitable units for panel production.

[0152] Figure 11 It is a flowchart of a method for preparing a light-emitting device provided by an embodiment of the present disclosure. Refer toFigure 11 , the method steps include:

[0153] S31. Fabricate a composite substrate, which includes a first substrate, a second adhesive layer, and a second substrate. The first substrate and the second substrate are connected by the second adhesive layer.

[0154] Referring to step S21, it will not be elaborated here.

[0155] S32. Process the composite substrate and fabricate an antireflection film on the surface of the composite substrate.

[0156] Figure 12 It is a structural diagram in the preparation process of a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 12 , one side of the substrate 101 close to the second adhesive layer 107 is a roughened surface 201, and an antireflection film 106 is provided on one side of the roughened surface 201.

[0157] In one example, step S32 may include:

[0158] The first step is to roughen the surface of the first substrate.

[0159] In the embodiment of the present disclosure, under the condition that the temperature is 200 - 500 °C, use sulfuric acid or a mixed solution of sulfuric acid and phosphoric acid to etch the side of the first substrate away from the second substrate in the composite substrate, and the etching time is 0.5 - 10 h to form the roughened surface;

[0160] The ratio of the sulfuric acid and phosphoric acid mixed solution is 1:0.2 to 1:5. Roughening under the above conditions can make the substrate have a roughened surface and will not cause the substrate to crack due to over-etching.

[0161] Exemplarily, under the condition that the temperature is 300 °C, use a mixed solution with a ratio of sulfuric acid to phosphoric acid of 1:5 to etch the side of the first substrate away from the second substrate in the composite substrate, and the etching time is 5 h to form the roughened surface.

[0162] In the embodiment of the present disclosure, the roughening depth of the roughened surface is 0.2 - 2 μm. On the one hand, this depth can ensure a sufficient depth to improve the light extraction efficiency, and on the other hand, the substrate with a roughened surface of this depth can support the light-emitting diode chip.

[0163] Exemplarily, the roughening depth of the roughened surface is 1 μm.

[0164] In the embodiment of the present disclosure, the particle diameter of the roughened surface is 0.1 - 1.5 μm. This particle diameter can ensure the light-emitting efficiency and the substrate support effect.

[0165] Exemplarily, the particle diameter of the roughened surface is 1 μm.

[0166] In the embodiments of the present disclosure, the particles for roughening the surface are generally in the shapes of a cone, a frustum of a cone, a cylinder, a hemisphere, etc.

[0167] Step 2: Fabricate an antireflection film on the surface of the first substrate away from the first adhesive layer.

[0168] In the embodiments of the present disclosure, the antireflection film can be made of transparent materials such as SiO 2 etc. The antireflection film made of the above materials can improve the light-emitting efficiency of the light-emitting device.

[0169] Exemplarily, the antireflection film is a SiO 2 film

[0170] In the embodiments of the present disclosure, the refractive index of the antireflection film can be less than that of the first substrate.

[0171] In this implementation, the refractive index of the antireflection film is less than that of the first substrate, so as to achieve an antireflection effect, improve the light transmittance, and thus improve the brightness of the light-emitting diode.

[0172] S33: Thin the first substrate and fabricate a first adhesive layer on the surface of the first substrate away from the second substrate. The thickness of the thinned first substrate is 5 - 50 μm.

[0173] Referring to step S22, details are not described herein again.

[0174] S34: Transfer a plurality of light-emitting diode chips to the side of the first substrate having the first adhesive layer.

[0175] Referring to step S23, details are not described herein again.

[0176] S35: Fabricate an electrode structure layer for the light-emitting diode chip.

[0177] Referring to step S24, details are not described herein again.

[0178] S36: Bond the side of the first substrate provided with the light-emitting diode chips to the tape.

[0179] Referring to step S25, details are not described herein again.

[0180] S37: Remove the second substrate and the second adhesive layer.

[0181] Referring to step S26, details are not described herein again.

[0182] S38: Cut the first substrate to form the light-emitting device.

[0183] Referring to step S27, details are not described herein again.

[0184] Figure 13It is a flowchart of a method for manufacturing a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 13 , and the steps of the method include:

[0185] S41. Fabricate a composite substrate, which includes a first substrate, a second adhesive layer, and a second substrate. The first substrate and the second substrate are connected by the second adhesive layer.

[0186] Refer to step S21, which will not be elaborated here.

[0187] S42. Process the composite substrate and fabricate an antireflection film on the surface of the composite substrate.

[0188] Refer to step S32, which will not be elaborated here.

[0189] S43. Thin the first substrate and fabricate a first adhesive layer on the surface of the first substrate away from the second substrate. The thickness of the thinned first substrate is 5 - 50 μm.

[0190] Refer to step S22, which will not be elaborated here.

[0191] S44. Transfer a plurality of light-emitting diode chips to the side of the first substrate with the first adhesive layer.

[0192] Refer to step S23. Different from S23, in this step, one light-emitting device only includes 1 light-emitting diode chip, and the colors of the light-emitting devices are the same.

[0193] S45. Pattern the first adhesive layer.

[0194] In this step, pattern the first adhesive layer to remove the first adhesive layer between the plurality of light-emitting diode chips.

[0195] Figure 14 It is a structural diagram in the process of manufacturing a light-emitting device provided by an embodiment of the present disclosure. Refer to Figure 14 , the side of the substrate 101 close to the second adhesive layer 107 is a roughened surface 201, and an antireflection film 106 is provided on one side of the roughened surface 201. The adhesive layer 102 has been patterned to remove the adhesive layer 102 between the plurality of light-emitting diode chips 103.

[0196] In the embodiment of the present disclosure, inductively coupled plasma etching (ICP) is used to pattern the first adhesive layer to remove the first adhesive layer between the plurality of light-emitting diode chips, so as to facilitate subsequent scribing processing.

[0197] S46. Bond the side of the first substrate with the light-emitting diode chips provided thereon to a tape.

[0198] Refer to step S25, which will not be elaborated here.

[0199] S47. Remove the second substrate and the second glue layer.

[0200] Refer to step S26, which will not be elaborated here.

[0201] S48. Cut the first substrate to form the light-emitting device.

[0202] Refer to step S27, which will not be elaborated here.

[0203] The substrate fabricated by using the method provided in the embodiments of the present disclosure has a relatively thin thickness that cannot be achieved by related technologies, and a surface structure beneficial to improving the light extraction efficiency and modulating the light extraction angle can be selectively fabricated on the back surface of the substrate, thereby improving the display effect of pixel devices such as Micro LED in Package (MIP).

[0204] Light-emitting diodes are distributed on the substrate fabricated by using the method provided in the embodiments of the present disclosure through mass transfer, and a Redistribution Layer Process (RDL) is fabricated. The material of the substrate may include transparent materials such as glass and sapphire. Through debonding, the final thickness of the substrate is between 2 and 150 μm, and the back surface of the final substrate may have a rough surface or a separately fabricated photonic crystal structure to improve the light extraction efficiency and modulate the light extraction angle.

[0205] The above are only optional embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A light emitting device, characterized in that: The light-emitting device comprises: a substrate (101), a glue layer (102) and at least one light-emitting diode chip (103); The adhesive layer (102) is located on one side of the substrate (101); the light-emitting diode chip (103) is connected to the substrate (101) via the adhesive layer (102); and the thickness of the substrate (101) is 5 to 50 μm.

2. The light emitting device according to claim 1, characterized in that: A surface of the substrate (101) away from the light-emitting diode chip (103) is a roughened surface (201); The roughening depth of the roughened surface (201) is 0.2 to 2 μm; The particle diameter of the roughened surface (201) is 0.1 to 1.5 μm.

3. The light emitting device according to claim 2, characterized in that: The light emitting device further comprises: an anti-reflection film (106); The anti-reflection film (106) is located on the roughened surface (201) of the substrate (101), and the refractive index of the anti-reflection film (106) is smaller than the refractive index of the substrate (101).

4. The light emitting device according to any one of claims 1 to 3, characterized in that: The light emitting device further comprises a light absorbing layer (141), a connecting electrode layer (142), an insulating layer (143) and four electrode pads (144); The light absorbing layer (141) wraps the light emitting diode chip (103); the connecting electrode layer (142) is located on a surface side of the light absorbing layer (141) away from the light emitting diode chip (103), and is electrically connected to the light emitting diode chip (103); the insulating layer (143) wraps the connecting electrode layer (142); and the four electrode pads (144) are located on a surface side of the insulating layer (143) away from the connecting electrode layer (142), and are electrically connected to the connecting electrode layer (142).

5. A method for preparing a light emitting device, characterized in that: The method comprises: Manufacturing a composite substrate, the composite substrate comprising a first substrate, a second adhesive layer and a second substrate, the first substrate and the second substrate being connected via the second adhesive layer; Thinning the first substrate and forming a first adhesive layer on a surface of the first substrate away from the second substrate, wherein the thickness of the first substrate after thinning is 5 to 50 μm; Transferring a plurality of light-emitting diode chips to a side of the first substrate having the first adhesive layer; removing the second substrate and the second adhesive layer; The first substrate is cut to form the light emitting device.

6. The method for preparing a light emitting device according to claim 5, characterized in that: The thickness of the first substrate before thinning is 200-700 μm; The thickness of the second substrate is 200-700 μm.

7. The method for preparing a light emitting device according to claim 5 or 6, characterized in that: The method further comprises: Before manufacturing the composite substrate, roughening the first substrate to form a roughened surface; The roughening depth of the roughened surface is 0.2 to 2 μm; The particle diameter of the roughened surface is 0.1 to 1.5 μm.

8. The method for preparing a light emitting device according to claim 7, characterized in that: The surface of the composite substrate is roughened, comprising: At a temperature of 200 to 500° C., using sulfuric acid or a mixed solution of sulfuric acid and phosphoric acid to corrode a surface of the first substrate in the composite substrate away from the second substrate for a corrosion time of 0.5 to 10 hours to form the roughened surface; The ratio of the sulfuric acid to phosphoric acid mixed solution is 1:0.2 to 1:

5.

9. The method for preparing a light emitting device according to claim 5 or 6, characterized in that: The method further comprises: An anti-reflection film is formed on a surface side of the first substrate away from the first adhesive layer, and a refractive index of the anti-reflection film is smaller than a refractive index of the first substrate.

10. The method for preparing a light emitting device according to claim 9, characterized in that: The method further comprises: The first adhesive layer is patterned to remove the first adhesive layer between the plurality of light emitting diode chips.

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