Light-emitting structure and miniature light-emitting device

Abstract

The utility model provides a light-emitting structure and a miniature light-emitting device, and relates to the field of miniature light-emitting devices.The light-emitting structure comprises a light-emitting chip, a solder layer, a driving chip and a bonding pad, the solder layer comprises a first plugging end and a welding end, the first plugging end is at least partially connected with the light-emitting chip, and the welding end is at least partially connected with the light-emitting chip; the welding end is bent into an arc shape in the direction deviating from the light-emitting chip, the welding end is provided with a plurality of welding rods arranged at intervals, a first concave part is defined between every two adjacent welding rods, the driving chip and the light-emitting chip are oppositely arranged, and the bonding pad is arranged on the driving chip. According to the light-emitting structure, the influence of the pressure in the bonding process is small, the problem of short circuit caused by connection of the welding flux and the adjacent pixel point welding flux due to too large bonding pressure can be solved, and the problem of pseudo soldering of the welding flux and the bonding pad due to too small bonding pressure can be solved.

Description

Technical Field

[0001] The present application relates to the field of micro-light-emitting devices, and in particular to a light-emitting structure and a micro-light-emitting device. Background Art

[0002] Micro LEDs (Micro Light Emitting Diodes) offer high resolution, low power consumption, high brightness, high contrast, high color saturation, fast response, thinness, and long life. They are widely used in wearable devices, ultra-large indoor display screens, head-mounted displays, head-up displays, taillights, wireless optical communications, AR / VR, projectors, and more.

[0003] During the manufacturing process of Micro LED, the LED chip and IC chip need to be connected to the pad through solder to achieve conductivity in the bonding area. However, when conventional solder and pad are welded, there is a problem of solder connecting with the solder of adjacent pixels, causing a short circuit and affecting the yield of Micro LED products. Utility Model Content

[0004] In order to overcome the deficiencies in the prior art, the present application provides a light-emitting structure and a micro light-emitting device.

[0005] In a first aspect, the present application provides a light-emitting structure, comprising: a light-emitting chip, a solder layer, a driver chip and a solder pad, the solder layer comprising a first plug-in end and a soldering end, the first plug-in end being at least partially connected to the light-emitting chip, the soldering end being bent into an arc in a direction away from the light-emitting chip, and the soldering end having a plurality of spaced-apart solder rods, and a first recess being defined between two adjacent solder rods, the driver chip being arranged opposite to the light-emitting chip, and the soldering pad being arranged on the driver chip.

[0006] In combination with the first aspect, in a possible embodiment, the soldering pad includes a second plug-in end and a receiving end, the second plug-in end at least partially extends into the driver chip and is connected to the driver chip, and the receiving end has a plurality of receiving spaces, which are used to receive the melted welding rod.

[0007] In combination with the first aspect, in a possible implementation manner, the first recessed portion is recessed in a direction close to the light-emitting chip, and a first preset distance exists between two adjacent welding rods.

[0008] In combination with the first aspect, in a possible implementation manner, the receiving end has a plurality of columns, and there is a second preset distance between two adjacent columns, and the second preset distance is greater than or equal to the first preset distance.

[0009] In combination with the first aspect, in a possible implementation, the light-emitting chip is arranged along a first preset direction, a first mounting hole is provided on the light-emitting chip, and the first plug-in end is inserted into the first mounting hole to connect with the light-emitting chip.

[0010] In combination with the first aspect, in a possible embodiment, the light-emitting chip includes: a light-emitting layer and a first substrate layer, the first mounting hole is arranged on the light-emitting layer, the first substrate layer is arranged on the side of the light-emitting layer away from the first mounting hole, and the first substrate layer is connected to the light-emitting layer.

[0011] In combination with the first aspect, in a possible implementation, the welding rod is arranged along the second preset direction, and the length of the welding rod along the second preset direction is negatively correlated with the distance that the welding rod deviates from the center line of the welding end.

[0012] In combination with the first aspect, in a possible implementation manner, a second mounting hole is provided on the driver chip, and the solder pad is inserted into the second mounting hole to be connected to the driver chip.

[0013] In combination with the first aspect, in a possible embodiment, the driver chip includes: a circuit structure layer and a second substrate layer, the second mounting hole is arranged on the circuit structure layer, and the length of the second mounting hole along the second preset direction is smaller than the length of the circuit structure layer along the second preset direction, the second substrate layer is arranged on the side of the circuit structure layer away from the second mounting hole, and the second substrate layer is connected to the circuit structure layer.

[0014] In a second aspect, the present application provides a micro-light-emitting device comprising the above-mentioned light-emitting structure.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] The light-emitting structure provided by the present application has a plurality of welding rods arranged at intervals on the welding end. When pressing down the light-emitting chip, the problem of solder connecting with the adjacent pixel solder can be reduced, thereby improving the yield of the product. The first recessed portion on the welding end reduces the total amount of solder in the solder layer, increases the contact area between the welding rod and the pad, and accelerates the discharge of internal stress during the bonding process, thereby further improving the yield of the product. The welding end is bent into an arc in the direction away from the light-emitting chip so that the lengths of the welding rods are different, which further reduces the total amount of solder in the solder layer and increases the pressure resistance during the bonding process. Compared with conventional solder without recessed portions, the light-emitting structure of the present application is less affected by the pressure during the bonding process, which can reduce the problem of short circuit caused by the solder connecting with the adjacent pixel solder due to excessive bonding pressure, and can reduce the problem of poor soldering between the solder and the pad due to insufficient bonding pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A schematic diagram showing the structure of the key and front of the light emitting structure;

[0019] Figure 2 A schematic structural diagram of a light-emitting chip showing a light-emitting structure;

[0020] Figure 3 A schematic structural diagram of a solder layer of a light-emitting structure is shown;

[0021] Figure 4 A schematic structural diagram of a solder layer of another embodiment of a light-emitting structure is shown;

[0022] Figure 5 A schematic structural diagram of a driving chip of a light-emitting structure is shown.

[0023] Description of main component symbols:

[0024] 100-light-emitting chip; 110-light-emitting layer; 111-first mounting hole; 112-first contact surface; 113-second contact surface; 120-first substrate layer; 200-solder layer; 210-first plug-in terminal; 220-welding terminal; 221-first recessed portion; 230-welding rod; 300-driver chip; 310-circuit structure layer; 311-second mounting hole; 320-second substrate layer; 400-solder pad; 410-second plug-in terminal; 420-receiving terminal; 421-second recessed portion; 430-receiving space; 440-column. DETAILED DESCRIPTION

[0025] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0026] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0028] In this application, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on specific circumstances.

[0029] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0030] Example 1

[0031] See also Figure 1 , the embodiment of the present application provides a light emitting structure, including: a light emitting chip 100, a solder layer 200, a driver chip 300 and a pad 400. Please refer to Figure 2 The solder layer 200 includes a first plug end 210 and a soldering end 220. The first plug end 210 at least partially extends into the light emitting chip 100 and is connected to the light emitting chip 100. Figure 3 The welding end 220 is bent into an arc in a direction away from the light-emitting chip 100, and the welding end 220 has a plurality of welding rods 230 arranged at intervals, and a first recessed portion 221 is defined between two adjacent welding rods 230. The driver chip 300 layer is arranged opposite to the light-emitting chip 100. The soldering pad 400 includes a second plug-in end 410 and a receiving end 420. The second plug-in end 410 at least partially extends into the driver chip 300 layer and is connected to the driver chip 300 layer. The receiving end 420 has a plurality of receiving spaces 430, and the receiving spaces 430 are used to receive the melted welding rods 230. During the process of pressing down the light-emitting chip 100, each receiving space 430 increases the space for accommodating the solder rod 230, reducing the problem of solder connecting with the solder of adjacent pixels and improving the product yield. Furthermore, the first recessed portion 221 on the soldering end 220 reduces the total amount of solder in the solder layer 200, increases the contact area between the solder rod 230 and the solder pad 400, and accelerates the discharge of internal stress during the bonding process, further improving the product yield. The soldering end 220 is curved in an arc shape away from the light-emitting chip 100, so that the lengths of the solder rods 230 are different. This further reduces the total amount of solder in the solder layer 200 and increases the pressure it can withstand during the bonding process. Compared with conventional solders without recessed portions and solder pads without receiving space 430, the light-emitting structure of the present application is less affected by the pressure during the bonding process, which can reduce the problem of short circuit caused by the solder connecting with the solder of adjacent pixels due to excessive bonding pressure, and can reduce the problem of cold soldering between the solder and the pad due to insufficient bonding pressure.

[0032] See also Figure 1 and Figure 2 In some embodiments, the light-emitting chip 100 is an LED chip layer, the light-emitting chip 100 is arranged along a first preset direction, and a first mounting hole 111 is provided on the light-emitting chip 100. The first plug end 210 is inserted into the first mounting hole 111 to connect with the light-emitting chip 100.

[0033] In some embodiments, the shape of the first plug end 210 matches the shape of the first mounting hole 111, and the size of the first plug end 210 is equal to the size of the first mounting hole 111. The first mounting hole 111 is hemispherical.

[0034] In other embodiments, the first mounting hole 111 may also be in the shape of a prism, a cylinder, a pyramid, etc., which are not listed here one by one.

[0035] In some embodiments, there are a plurality of first mounting holes 111 , and the first mounting holes 111 are arranged on the light emitting chip 100 at intervals along the first preset direction.

[0036] See also Figure 2 In some embodiments, the light-emitting chip 100 includes a light-emitting layer 110 and a first substrate layer 120. The first mounting hole 111 is provided on the light-emitting layer 110. The first substrate layer 120 is provided on a side of the light-emitting layer 110 facing away from the first mounting hole 111, and the first substrate layer 120 is connected to the light-emitting layer 110.

[0037] See also Figure 2 In some embodiments, the light-emitting layer 110 includes a first contact surface 112 and a second contact surface 113 disposed opposite each other. The first mounting hole 111 is disposed on the first contact surface 112 and extends through the first contact surface 112 along a second predetermined direction. The second contact surface 113 is connected to the first substrate layer 120. The first plug-in terminal 210 is inserted into the first mounting hole 111 to connect to the light-emitting layer 110.

[0038] In some embodiments, the length of the first mounting hole 111 along the second preset direction is less than the length of the light-emitting layer 110 along the second preset direction. The second preset direction is perpendicular to the first preset direction. The first preset direction is a horizontal direction. The second preset direction is a vertical direction.

[0039] See also Figure 5In some embodiments, the driver chip 300 layer is an IC chip layer, the driver chip 300 layer is arranged along the first preset direction, and the length of the driver chip 300 layer along the first preset direction is equal to the length of the light-emitting chip 100 along the first preset direction.

[0040] See also Figure 5 In some embodiments, the driver chip 300 layer is provided with a second mounting hole 311. The second plug-in terminal 410 is inserted into the second mounting hole 311 to connect to the driver chip 300 layer. The driver chip 300 layer has a light-emitting surface. The second mounting hole 311 penetrates the light-emitting surface along the second predetermined direction.

[0041] In some embodiments, the shape of the second plug end 410 matches the shape of the second mounting hole 311, and the size of the second plug end 410 is equal to the size of the second mounting hole 311. The second mounting hole 311 is prismatic.

[0042] In other embodiments, the second mounting hole 311 may also be in a hemispherical shape, a cylindrical shape, a pyramidal shape, etc., which are not listed here one by one.

[0043] In some embodiments, there are multiple second mounting holes 311 , the number of the second mounting holes 311 is equal to the number of the first mounting holes 111 , and the second mounting holes 311 are arranged on the driver chip 300 layer at intervals along the first preset direction.

[0044] See also Figure 5 In some embodiments, the driver chip 300 layer includes: a circuit structure layer 310 and a second substrate layer 320. The light-emitting surface is located on a side of the circuit structure layer 310 facing away from the second substrate layer 320. The second mounting hole 311 is provided on the circuit structure layer 310, and the length of the second mounting hole 311 along the second preset direction is less than the length of the circuit structure layer 310 along the second preset direction. The second substrate layer 320 is provided on a side of the circuit structure layer 310 facing away from the second mounting hole 311, and the second substrate layer 320 is connected to the circuit structure layer 310.

[0045] See also Figure 3 In some embodiments, the welding end 220 is hemispherical. The first recessed portion 221 is recessed toward the light-emitting layer 110 , and there are multiple first recessed portions 221 , so that the welding end 220 is sawtooth-shaped, and the welding end 220 has multiple welding rods 230 .

[0046] See also Figure 4In other embodiments, the welding end 220 is square.

[0047] In some embodiments, the welding rod 230 is arranged along the second preset direction, the lengths of two adjacent welding rods 230 along the second direction are different, and the length of the welding rod 230 along the second preset direction is negatively correlated with the distance that the welding rod 230 deviates from the center line of the welding end 220, so that the welding rods 230 on both sides of the welding end 220 are shorter than the welding rod 230 in the middle of the welding end 220, so that the welding rod 230 and the welding pad 400 can be connected by increasing the pressure during the bonding process, and at the same time, it can also ensure that the solder and other pixel point solders will not be connected to each other during the pressure increase process to cause a short circuit, thereby improving the product yield.

[0048] See also Figure 5 In some embodiments, a second recessed portion 421 is provided on the receiving end 420 , and the second recessed portion 421 is recessed in a direction away from the light emitting chip 100 , so that the receiving end 420 has a plurality of columns 440 . Two adjacent columns 440 form the receiving space 430 .

[0049] In some embodiments, the columns 440 are prismatic, and the lengths of two adjacent columns 440 along the second preset direction are equal. The columns 440 and the welding rods 230 are staggered along the first preset direction, so that the welding rods 230 and the accommodating space are in corresponding positions during the bonding process, which can increase the accommodating space of the welding rods 230.

[0050] In some embodiments, there is a first preset distance between two adjacent welding rods 230. There is a second preset distance between two adjacent columns 440. The second preset distance is greater than or equal to the first preset distance.

[0051] During bonding, downward pressure flattens the solder, causing it to contact and connect with the pad below. When the pressure is high, the solder is likely to connect with the solder of the adjacent pixel, causing a short circuit. When the pressure is low, the solder is likely to fail to bond and connect with the pad below, causing an open circuit. In the light-emitting structure of the present application, the soldering end 220 is curved into an arc in a direction away from the light-emitting chip 100, and a first recessed portion 221 is provided on the soldering end 220 to space the solder rods 230 apart, thereby increasing the contact area between the solder rods 230 and the pad 400 and accelerating the discharge of internal stress during the bonding process. Furthermore, the lengths of the adjacent solder rods 230 are different, and the solder rods 230 are located in corresponding positions with the accommodation space. During the bonding process, increasing the pressure allows the solder to fully fill the accommodation space, thereby alleviating the problem of short circuits caused by the solder connecting with the adjacent pixel due to excessive bonding pressure. This can increase the pressure tolerance during the bonding process and improve the product yield.

[0052] Example 2

[0053] An embodiment of the present application provides a micro-light-emitting device (not shown in the figure), which includes the light-emitting structure in any one of the above embodiments, and therefore has all the beneficial effects of the light-emitting structure in any one of the above embodiments, which will not be described here one by one.

[0054] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0055] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A light-emitting structure, characterized in that: include: Light-emitting chip; a solder layer, the solder layer comprising a first plugging end and a welding end, the first plugging end being at least partially connected to the light-emitting chip, the welding end being bent into an arc shape in a direction away from the light-emitting chip, and the welding end having a plurality of welding rods arranged at intervals, with a first recess being defined between two adjacent welding rods; A driving chip, the driving chip being arranged opposite to the light-emitting chip; A pad is provided on the driver chip.

2. The light emitting structure according to claim 1, characterized in that: The soldering pad includes a second plug-in end and a receiving end. The second plug-in end at least partially extends into the driver chip and is connected to the driver chip. The receiving end has a plurality of receiving spaces, and the receiving spaces are used to receive the melted soldering rod.

3. The light emitting structure according to claim 2, characterized in that: The first recessed portion is recessed in a direction close to the light emitting chip, and a first preset distance exists between two adjacent welding rods.

4. The light emitting structure according to claim 3, characterized in that: The receiving end has a plurality of columns, and there is a second preset distance between two adjacent columns, and the second preset distance is greater than or equal to the first preset distance.

5. The light emitting structure according to claim 1, characterized in that: The light emitting chip is arranged along a first preset direction. A first mounting hole is provided on the light emitting chip. The first plug end is inserted into the first mounting hole to be connected to the light emitting chip.

6. The light emitting structure according to claim 5, characterized in that: The light-emitting chip includes: a light-emitting layer, wherein the first mounting hole is provided on the light-emitting layer; A first substrate layer is provided on a side of the light-emitting layer away from the first mounting hole, and the first substrate layer is connected to the light-emitting layer.

7. The light emitting structure according to claim 6, characterized in that: The welding rod is arranged along a second preset direction, and the length of the welding rod along the second preset direction is negatively correlated with the distance the welding rod deviates from the center line of the welding end.

8. The light emitting structure according to claim 1, characterized in that: A second mounting hole is provided on the driving chip, and the solder pad is inserted into the second mounting hole to be connected to the driving chip.

9. The light emitting structure according to claim 8, characterized in that: The driver chip includes: A circuit structure layer, wherein the second mounting hole is provided on the circuit structure layer, and a length of the second mounting hole along a second preset direction is smaller than a length of the circuit structure layer along the second preset direction; The second substrate layer is arranged on a side of the circuit structure layer away from the second mounting hole, and the second substrate layer is connected to the circuit structure layer.

10. A micro light-emitting device, characterized in that: The light-emitting structure comprises the light-emitting structure according to any one of claims 1 to 9.

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