Light emitting diode display device and manufacturing method thereof

Abstract

The present invention provides a light emitting diode display device and a manufacturing method thereof. The light emitting diode display device comprises a substrate, a plurality of light emitting diodes, a glue material and a packaging glue. The light emitting diodes are arranged on the substrate. The glue material is arranged between the substrate and the light emitting diodes. The glue material comprises a plurality of parts, which are respectively located between two adjacent light emitting diodes, and the height of at least one of the parts is different from the height of the other parts. The glue material is arranged on the glue material and the light emitting diodes.

Description

Technical Field

[0001] The present disclosure relates to a light emitting diode display device and a method for manufacturing the light emitting diode display device. Background Art

[0002] One of the current manufacturing methods of LED packaging structure is flip chip eutectic technology. After the LED is bonded to the substrate, the encapsulation film sealing process is then performed. However, the lamination process in the film sealing process causes the LED located at the edge or corner of the substrate to shift or fail. As a result, the joints of the spliced ​​display device will become obvious.

[0003] In the prior art, the thickness of the light shielding layer disposed on the substrate is not conducive to the operation of the LED bonding process. If the light shielding layer is avoided from the peripheral area of ​​the LED, the metal circuit of the substrate will reflect light and affect the display effect of the display device.

[0004] In view of this, how to provide a light emitting diode display that can solve the above problems is still a goal of research and development in this field. Summary of the invention

[0005] A technical aspect of the present disclosure is a light emitting diode display device.

[0006] In one embodiment, a light emitting diode display device comprises a substrate, a plurality of light emitting diodes, a glue material and a packaging glue. The light emitting diodes are arranged on the substrate. The glue material is arranged between the substrate and the light emitting diodes. The glue material comprises a plurality of parts, each of which is located between two adjacent light emitting diodes, and the height of at least one of the parts is different from the height of the other parts. The packaging glue is arranged on the glue material and the light emitting diodes.

[0007] In one embodiment, there is a distance between two adjacent light emitting diodes. The greater the distance between the adjacent light emitting diodes, the lower the height of the corresponding portion of the adhesive.

[0008] In one embodiment, the upper surface of the adhesive material is arc-shaped.

[0009] In one embodiment, each light emitting diode has a height, and the maximum height roughness of the adhesive is less than 15% of the height of the light emitting diode.

[0010] In one embodiment, the penetration rate of the adhesive is less than 1%.

[0011] In one embodiment, the substrate has a side wall, and the light emitting diode display device further includes a light shielding sealant disposed on the side wall of the substrate.

[0012] In one embodiment, the penetration rate of the light-shielding sealant is less than 1% and greater than 0.1%.

[0013] In one embodiment, the packaging glue is separated from the sidewall of the substrate by a light shielding sealant.

[0014] In one embodiment, the upper surface of the light shielding sealant is higher than the upper surface of the substrate.

[0015] Another technical aspect of the present disclosure is a method for manufacturing a light emitting diode display device.

[0016] In one embodiment, a method for manufacturing a light emitting diode display device includes forming a first packaging structure. The first packaging structure includes bonding a plurality of light emitting diodes to a substrate, filling a liquid adhesive between the substrate and the light emitting diodes, curing the liquid adhesive to form a cured adhesive, and placing a packaging adhesive on the cured adhesive and the light emitting diodes.

[0017] In one embodiment, there is a distance between two adjacent LEDs, and the step of filling the liquid adhesive between the substrate and the LEDs further includes the step of lowering the height of the liquid adhesive between the two adjacent LEDs as the distance between the LEDs increases.

[0018] In one embodiment, the step of filling the liquid glue is performed by dispensing, spraying or screen printing.

[0019] In one embodiment, the packaging adhesive is disposed by lamination.

[0020] In one embodiment, the method for manufacturing the light emitting diode display device further includes forming a second packaging structure, and splicing the first packaging structure and the second packaging structure.

[0021] In one embodiment, the method for manufacturing the light emitting diode display device further includes disposing a light shielding sealant on the side wall of the substrate before splicing the first packaging structure and the second packaging structure.

[0022] In the above embodiment, by placing liquid adhesive between the substrate and the LED, and not performing a lamination process before curing the adhesive, the LED can be prevented from shifting or failing. The liquid adhesive can fill the gap between the substrate and the LED, so the adhesive after curing can stabilize the bonding strength between the LED and the substrate. In addition, the adhesive is an opaque material, which can prevent the metal circuit from reflecting light, so that the joint of the LED display device becomes less obvious, and the yield and display quality of the LED display device are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a cross-sectional view of a light emitting diode display device according to an embodiment of the present disclosure.

[0024] Figure 2The figure is a flow chart of a method for manufacturing a light emitting diode package structure according to an embodiment of the present disclosure.

[0025] FIG. 3A to FIG. 3E for Figure 2 A cross-sectional view of an intermediate step of a method for manufacturing a light emitting diode package structure.

[0026] Figure 4 The figure is a flow chart of a method for manufacturing a light emitting diode package structure according to another embodiment of the present disclosure.

[0027] FIG. 5A to FIG. 5B for Figure 4 A cross-sectional view of an intermediate step of a method for manufacturing a light emitting diode package structure.

[0028] Figure 6 It is a cross-sectional view of a light emitting diode package structure according to an embodiment of the present disclosure.

[0029] Figure 7 It is a cross-sectional view of a light emitting diode package structure according to an embodiment of the present disclosure.

[0030] Wherein, the reference numerals are:

[0031] 10,20: Light Emitting Diode Display Device

[0032] 100A, 200A: First packaging structure

[0033] 100B, 200B: Second packaging structure

[0034] 300,400:Package structure

[0035] 110:Substrate

[0036] 112: Side wall

[0037] 114: Upper surface

[0038] 120a, 120b, 120c, 120d, 120e, 120f: light emitting diodes

[0039] 120T: Top

[0040] 130: Rubber

[0041] 130L:Liquid glue

[0042] 130T: Upper surface

[0043] 131,132,133,134,135,136,137,138: Part

[0044] 140: Packaging glue

[0045] 150:Joint

[0046] 160,160a,160b:Light-shielding sealant

[0047] 162a, 162b: upper surface

[0048] d1,d2,d3,d4: distance

[0049] H,h1,h2,h3,h4,h5,h6,h7,h8: height

[0050] Z: vertical direction

[0051] P1: UV curing method

[0052] P2: Lamination method

[0053] T:Joint

[0054] S11~S15, S21~S26: Steps DETAILED DESCRIPTION

[0055] The following will disclose multiple embodiments of the present invention with drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present invention. That is, in some embodiments of the present invention, these practical details are not necessary. In addition, in order to simplify the drawings, some structures and elements commonly used in the prior art will be depicted in the drawings in a simple schematic manner. And for the sake of clarity, the thickness of the layers and regions in the drawings may be exaggerated, and the same element symbols represent the same elements in the description of the drawings.

[0056] Figure 1 FIG. 1 is a cross-sectional view of an LED display device 10 according to an embodiment of the present disclosure. The LED display device 10 may be a micro LED display device or a sub-millimeter LED display device. The LED display device 10 is formed by splicing a first package structure 100A and a second package structure 100B. The first package structure 100A and the second package structure 100B have substantially the same components.

[0057] The first packaging structure 100A includes a substrate 110, a plurality of light-emitting diodes 120a, 120b, 120c, an underfill 130, and a packaging glue 140. The light-emitting diodes 120a, 120b, 120c are disposed on the substrate 110. The underfill 130 is disposed between the substrate 110 and the light-emitting diodes 120a, 120b, 120c. The packaging glue 140 is disposed on the underfill 130 and the light-emitting diodes 120a, 120b, 120c. The second packaging structure 100B includes a substrate 110, a plurality of light-emitting diodes 120d, 120e, 120f, an underfill 130, and a packaging glue 140. The underfill 130 is disposed between the substrate 110 and the light-emitting diodes 120d, 120e, 120f. The packaging glue 140 is disposed on the underfill 130 and the light-emitting diodes 120d, 120e, 120f.

[0058] The LEDs 120a-120f are bonded to the substrate 110 through the bonding member 150. The adhesive 130 partially surrounds the LEDs 120a-120f. In other words, the height of the adhesive 130 exceeds the height of the bonding member 150 and is lower than the top 120T of the LEDs 120a-120f. Therefore, the adhesive 130 can stabilize the bonding strength between the LEDs 120a-120f and the substrate 110, and prevent the LEDs 120a-120f from shifting or failing in subsequent processes.

[0059] From a cross-sectional perspective, the adhesive 130 of the first package structure 100A includes a plurality of parts 131, 132, 135, and 136. The aforementioned parts 131, 132, 135, and 136 are substantially integrally formed, and are only divided into a plurality of parts for illustration from a cross-sectional perspective. Part 131 of the adhesive 130 is located between adjacent LEDs 120a and 120b, and part 132 of the adhesive 130 is located between adjacent LEDs 120b and 120c. Parts 135 and 136 of the adhesive 130 are located at the edge of the first package structure 100A, and part 136 is located between LED 120c and LED 120d.

[0060] The adhesive 130 of the LED display device 10 is in liquid state when disposed between the LEDs 120a-120f and the substrate 110, and then cured to stabilize the LEDs 120-120f. Therefore, the adhesive 130 does not undergo a lamination process before curing, which can prevent the LEDs 120a-120f located at the edges and corners of the first packaging structure 100A from shifting or failing due to pressure. Due to such a design, the height of at least one of the above-mentioned parts 131, 132, 135, 136 is different from the height of the others. For example, in this embodiment, the heights h1 and h2 of the parts 131 and 132 are greater than the heights h5 and h6 of the parts 135 and 136.

[0061] Similarly, the adhesive 130 of the second package structure 100B includes a plurality of portions 133, 134, 137, and 138. The portion 133 of the adhesive 130 is located between the adjacent LEDs 120d and 120e. The portion 134 of the adhesive 130 is located between the adjacent LEDs 120e and 120f. The portions 137 and 138 of the adhesive 130 are located at the edge of the second package structure 100B, wherein the portion 137 is located between the LED 120d and the LED 120c. The heights h3 and h4 of the portions 133 and 134 are greater than the heights h7 and h8 of the portions 137 and 138.

[0062] Specifically, the greater the distance between two adjacent LEDs 120a-120f, the lower the height of the corresponding parts 131-138. For example, in the present embodiment, there is a distance d1 between the LED 120a and the LED 120b, and there is a distance d2 between the LED 120b and the LED 120c. The distance d1 is substantially equal to the distance d2, and the heights h1 and h2 of the corresponding parts 131 and 132 are also substantially equal. There is a distance d3 between the LED 120d and the LED 120e, and there is a distance d4 between the LED 120e and the LED 120f. The distance d4 is greater than the distance d3, and the height h3 of the corresponding part 133 is greater than the height h4 of the part 134.

[0063] Since the adhesive material 130 is in liquid state when disposed between the LEDs 120a-120f and the substrate 110, and the adhesive material 130 is not subjected to a lamination process before being cured, the upper surface 130T of the adhesive material 130 is arc-shaped. For example, the upper surface 130T of the portions 131, 132, 133, and 134 of the adhesive material 130 is a concave arc-shaped, while the portions 135, 136, 137, and 138 at the edges are gradually flattened arc-shaped. In other words, the heights h5, h6, h7, and h8 of the portions 135, 136, 137, and 138 at the edges are smaller than the heights h1 to h4.

[0064] The light-emitting diodes 120a-120f have a height H, and the maximum height roughness (Rz) of the adhesive 130 is less than 15% of the height H of the light-emitting diodes 120a-120f. The maximum height roughness is defined as the height difference of the surface of the adhesive 130 in the vertical direction Z. In other words, compared with the surface after the etching process, the surface of the adhesive 130 is smoother. For example, the height H of the light-emitting diodes 120a-120f is about 10 microns, and the maximum height roughness of the adhesive 130 is less than 1.5 microns, but the present disclosure is not limited thereto.

[0065] The material of the adhesive 130 is a non-transparent material, such as resin, color resist, etc. The transmittance of the adhesive 130 is less than 1%, so the adhesive 130 can also prevent the metal circuit of the substrate 110 from reflecting light. The transmittance of the packaging glue 140 is greater than 50%, but the disclosure is not limited thereto.

[0066] According to the above, since the adhesive 130 is in liquid state when disposed between the LEDs 120a-120f and the substrate 110, and the adhesive 130 does not undergo a lamination process before curing, the LEDs 120a-120f located at the edges and corners of the first package structure 100A can be prevented from shifting or failing due to pressure. In this way, the joint T between the first package structure 100A and the second package structure 100B can become less obvious, thereby improving the yield and display quality of the LED display device 10.

[0067] Figure 2 FIG. 1 is a flow chart of a method for manufacturing a light emitting diode package structure according to an embodiment of the present disclosure. Figure 1 Take the light emitting diode display device 10 as an example. FIG. 3A to FIG. 3D for Figure 2 1 is a cross-sectional view of an intermediate step of a method for manufacturing a light emitting diode display device 10.

[0068] See also Figure 2 Step S11 and Figure 3A . In step S11, a plurality of light-emitting diodes 120a-120c are bonded to the substrate 110. The light-emitting diodes 120a-120c can be bonded to the substrate 110 by mass transfer, and the light-emitting diodes 120a-120c are electrically connected to the metal circuit (not shown) in the substrate 110 by the bonding member 150. In step S11, when the light-emitting diodes 120a-120c are bonded to the substrate 110, no light-shielding material is disposed on the upper surface 114 of the substrate 110. In other words, the bonding effect of the light-emitting diodes 120a-120c will not be affected by the thickness of the light-shielding material on the substrate 110.

[0069] See also Figure 2 Step S12 and Figure 3B . In step S12, the liquid glue 130L is filled between the substrate 110 and the light-emitting diodes 120a-120c. The step of filling the liquid glue 130L can be performed by dispensing, spraying or screen printing. The liquid glue 130L can fill the gaps between the bonding members 150 and the gaps between the substrate 110 and the light-emitting diodes 120a-120c. In other words, the liquid glue 130L can cover the upper surface 114 of the substrate 110, and the liquid glue 130L also partially surrounds the light-emitting diodes 120a-120f.

[0070] See also Figure 2 Step S13, Figure 3B as well as Figure 3C . In step S13, the liquid glue 130L is cured to form the glue 130, for example, by ultraviolet light curing method P1. Since there is no need to undergo a lamination process before curing the liquid glue 130L, the light-emitting diodes 120a-120c can be prevented from shifting or failing. In addition, since the liquid glue 130L can fill the gaps between the substrate 110, the light-emitting diodes 120a-120c, and the bonding member 150, the cured glue 130 can stabilize the bonding strength between the light-emitting diodes 120a-120c and the substrate 110. As mentioned above, the cured glue 130 has an arc-shaped upper surface 130T, and the glue 130 has different heights depending on the distance between the light-emitting diodes 120a-120c. The glue 130 is an opaque material, such as a resin, a color resist, etc., so the glue 130 can prevent the metal circuit of the substrate 110 from reflecting light.

[0071] See also Figure 2 Step S14 and Figure 3D . In step S14, the packaging glue 140 is disposed on the adhesive material 130 and the light-emitting diodes 120a-120c. The packaging glue 140 is disposed on the adhesive material 130 by laminating method P2, and then the packaging glue 140 is thermally cured. In step S14, since the adhesive material 130 is in a cured state and the adhesive material 130 partially surrounds the light-emitting diodes 120a-120c. Therefore, the adhesive material 130 can stabilize the light-emitting diodes 120a-120c during the lamination process of step S14, and prevent the light-emitting diodes 120a or the light-emitting diodes 120ac located at the edges and corners of the first packaging structure 100A from shifting or failing due to pressure.

[0072] See also Figure 2 Step S15 and Figure 3E In step S15, the first package structure 100A and the second package structure 100B are spliced. The second package structure 100B can be formed by the aforementioned steps S11 to S14. Figure 3E As shown, since the adhesive 130 can stabilize the LEDs 120a-120c and prevent failure, and the adhesive 130 can also prevent the metal circuit from reflecting light, the joint T between the first package structure 100A and the second package structure 100B can become less obvious, thereby improving the yield and display quality of the LED display device 10.

[0073] Figure 4 FIG. 4 is a flow chart of a method for manufacturing a light emitting diode display device according to another embodiment of the present disclosure. FIG. 5A to FIG. 5B for Figure 4A cross-sectional view of an intermediate step of a method for manufacturing a light emitting diode display device. Figure 4 As shown, the manufacturing method of this embodiment includes steps S21 to S26, wherein steps S21 to S24 and Figure 2 Therefore, only steps S25 to S26 are described below, and the description of steps S21 to S24 is omitted.

[0074] See also Figure 4 Step S25 and Figure 5A In this embodiment, a first package structure 200A is formed according to steps S21 to S24. The first package structure 200A and Figure 3D The first packaging structure 100A shown is substantially the same, except that the first packaging structure 200A further includes a light shielding sealant 160. The light shielding sealant 160 is disposed on the two side walls 112 of the substrate 110. In the present embodiment, the light shielding sealant 160 covers the entire side wall 112. In other words, the packaging glue 140 in the present embodiment is separated from the side wall 112 of the substrate 110 by the light shielding sealant 160, and the packaging glue 140 does not extend to the side wall 112, but the present disclosure is not limited thereto. The transmittance of the light shielding sealant 160 is less than 1%.

[0075] See also Figure 4 Step S26 and Figure 5B . In step S26, the first packaging structure 200A and the second packaging structure 200B are spliced ​​to form the light-emitting diode display device 20. Both the first packaging structure 200A and the second packaging structure 200B can be formed by the aforementioned steps S21 to S25. Since the encapsulation glue 140 reflects light, the light-shielding sealant 160 can absorb the light reflected by the encapsulation glue 140, further making the splicing point T less obvious, so as to improve the yield and display quality of the light-emitting diode display device 20. In this embodiment, the transmittance of the encapsulation glue 140 can be greater than 90%, and by absorbing the reflected light of the encapsulation glue 140 by the light-shielding sealant 160, the technical effect of making the splicing point T less obvious can still be achieved.

[0076] Figure 6 FIG. 3 is a cross-sectional view of a package structure 300 according to an embodiment of the present disclosure. Figure 5A The first package structure 200A shown is substantially the same, and the difference is that the light shielding sealant 160a of the package structure 300 only covers a portion of the side wall 112, that is, the package sealant 140 covers another portion of the side wall 112. In other words, the upper surface 162a of the light shielding sealant 160a in this embodiment is lower than the upper surface 114 of the substrate 110. The package structure 300 has the same technical effect as the first package structure 200A, and will not be repeated here.

[0077] Figure 7 FIG. 4 is a cross-sectional view of a package structure 400 according to an embodiment of the present disclosure. Figure 6 The package structure 300 shown is substantially the same, and the difference is that the upper surface 162b of the light shielding sealant 160b of the package structure 400 is higher than the upper surface 114 of the substrate 110. In other words, the light shielding sealant 160b covers the entire side wall 112 of the substrate 110 and covers a portion of the side wall of the adhesive material 130. In other embodiments, the light shielding sealant 160b can also cover the entire side wall 112 of the adhesive material 130. The package structure 400 has the same technical effect as the package structure 300, and will not be repeated here.

[0078] In summary, the LED display device disclosed herein can prevent the LED from shifting or failing by placing a liquid adhesive between the substrate and the LED, and not undergoing a lamination process before curing the adhesive. The liquid adhesive can fill the gap between the substrate and the LED, so the adhesive after curing can stabilize the bonding strength between the LED and the substrate. In addition, the adhesive is an opaque material, which can prevent the metal circuit from reflecting light, so that the joint of the LED display device becomes less obvious, and the yield and display quality of the LED display device are improved.

[0079] Although the present invention has been disclosed as above in the form of an implementation method, it is not intended to limit the present invention. Anyone skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope of the attached patent application.

Claims

1. A light emitting diode display device, characterized in that: Include: a substrate; A plurality of light emitting diodes are disposed on the substrate; an adhesive material disposed between the substrate and the light emitting diodes, wherein the adhesive material comprises a plurality of parts, the parts are respectively located between two adjacent ones of the light emitting diodes, and the height of at least one of the parts is different from the height of the other parts; and A packaging adhesive is disposed on the adhesive material and the light-emitting diodes; The height of the adhesive is lower than the tops of the light emitting diodes. 2 . The light emitting diode display device as claimed in claim 1 , wherein there is a distance between two adjacent ones of the light emitting diodes, and the greater the distance between the adjacent light emitting diodes, the lower the height of the corresponding parts of the glue material. 3 . The light emitting diode display device as claimed in claim 1 , wherein an upper surface of the adhesive is arc-shaped. 4 . The light emitting diode display device as claimed in claim 1 , wherein each of the light emitting diodes has a height, and a maximum height roughness (Rz) of the adhesive is less than 15% of the height. 5 . The light emitting diode display device as claimed in claim 1 , wherein a transmittance of the adhesive is less than 1%.

6. The light emitting diode display device as claimed in claim 1, wherein the substrate has a side wall, and the light emitting diode display device further comprises: A light-shielding sealant is disposed on the side wall of the substrate. 7 . The light emitting diode display device as claimed in claim 6 , wherein the light shielding sealant has a transmittance less than 1%. 8 . The light emitting diode display device as claimed in claim 6 , wherein the packaging glue and the side wall of the substrate are separated by the light shielding sealant. 9 . The light emitting diode display device as claimed in claim 6 , wherein an upper surface of the light shielding sealant is higher than an upper surface of the substrate.

10. A method for manufacturing a light emitting diode display device, comprising forming a first packaging structure, characterized in that: Forming the first packaging structure includes: bonding a plurality of light emitting diodes to a substrate; Filling a liquid adhesive between the substrate and the light emitting diodes; solidifying the liquid adhesive to form a solidified adhesive; and Disposing a packaging glue on the cured glue material and the light emitting diodes; The height of the adhesive is lower than the tops of the light emitting diodes.

11. The method for manufacturing a light emitting diode display device as claimed in claim 10, wherein there is a distance between two adjacent ones of the light emitting diodes, and the step of filling the liquid adhesive between the substrate and the light emitting diodes further comprises: When the distance between the light emitting diodes is larger, the height of the liquid adhesive between two adjacent ones of the light emitting diodes is lower. 12 . The method for manufacturing a light emitting diode display device as claimed in claim 10 , wherein the step of filling the liquid glue is performed by dispensing, spraying or screen printing. 13 . The method for manufacturing a light emitting diode display device as claimed in claim 10 , wherein the step of disposing the packaging adhesive is performed by lamination.

14. The method for manufacturing a light emitting diode display device according to claim 10, further comprising: forming a second packaging structure; and The first packaging structure and the second packaging structure are spliced ​​together.

15. The method for manufacturing a light emitting diode display device according to claim 14, further comprising: Before splicing the first packaging structure and the second packaging structure, a light shielding sealant is disposed on a side wall of the substrate.

Images