LED support and LED device thereof

Abstract

The utility model relates to an LED support and an LED device thereof, the LED support is provided with an open containing cavity, the bottom wall of the containing cavity is covered with a blocking structure (102), the blocking structure (102) encloses to form a containing groove (104), a bonding pad assembly (106) used for installing a light-emitting chip (20) is arranged in the containing groove (104), and the blocking structure (102) is provided with a filler groove (1020) communicated with the containing groove (104); when a light-emitting chip (20) is installed on the bonding pad assembly (106), the orthographic projection of the filler groove (1020) on the bottom wall of the containing cavity protrudes out of the peripheral contour of the orthographic projection of the light-emitting chip (20) on the bottom wall of the containing cavity. According to the LED support, the risk of light attenuation of devices can be reduced, and the service life of the devices can be effectively prolonged.

Description

Technical Field

[0001] This utility model relates to the field of LED display technology, and in particular to an LED bracket and an LED device having the LED bracket. Background Technology

[0002] An LED bracket is a structure used for LED packaging. It has a hollow, bowl-shaped functional area. Inside the bowl are pads for mounting the light-emitting chip. The pads connect to metal pins on the outside of the bracket, thereby connecting the light-emitting chip to an external circuit and enabling circuit conduction. To improve conductivity and solderability, the bottom wall of the bowl is usually covered with a metal layer. However, this metal layer is prone to oxidation, forming an oxide layer that affects conductivity. Furthermore, the metal layer is also prone to sulfidation, forming silver sulfide, which can cause the light-emitting chip to fail, the functional area to darken, and ultimately, light decay.

[0003] To avoid decreased conductivity and light decay caused by oxidation and sulfidation of the metal layer, such as Figure 1-2 The existing LED bracket 10 shown has a barrier structure 102 covering the metal layer of the bottom wall of the bowl. The barrier structure 102 forms a receiving groove 104 in the middle area of ​​the bowl to accommodate the pad assembly 106. The barrier structure 102 is specifically a white adhesive layer. On the one hand, by covering the metal layer with the barrier structure 102, the contact area between the metal layer and the air is reduced. On the other hand, during the installation of the light-emitting chip 20, the barrier structure 102 can prevent the solder or conductive adhesive between the electrodes of the light-emitting chip 20 and the pad assembly 106 from overflowing.

[0004] However, in practical applications, LED devices using this type of LED bracket often experience light decay and other problems during long-term use, affecting the lifespan of the devices. Utility Model Content

[0005] Based on this, the purpose of this utility model is to overcome the defects or deficiencies of the prior art. On the one hand, it provides an LED bracket that can reduce the risk of light decay of the device and effectively improve the service life of the device.

[0006] An LED bracket has an open receiving cavity. The bottom wall of the receiving cavity is covered with a barrier structure, which encloses a receiving groove. The receiving groove is provided with a pad assembly for mounting a light-emitting chip. The barrier structure has a filling groove that communicates with the receiving groove. When a light-emitting chip is mounted on the pad assembly, the orthographic projection of the opening of the filling groove on the bottom wall of the receiving cavity protrudes beyond the outer periphery of the orthographic projection of the light-emitting chip on the bottom wall of the receiving cavity.

[0007] The LED bracket of this utility model has a filling groove in the barrier structure that communicates with the receiving groove on which the light-emitting chip is installed. After the light-emitting chip is installed, the gap between the bottom surface of the light-emitting chip and the bottom wall of the receiving groove is filled with filler material, which improves the heat dissipation effect of the bottom surface of the light-emitting chip. When the light-emitting chip is soldered to the pad assembly, the filled material seals the solder between the light-emitting chip and the pad assembly, preventing residual accelerant in the solder from evaporating when heated and penetrating into the light-emitting chip, thus avoiding light decay caused by performance damage to the light-emitting chip and effectively improving the service life of the device.

[0008] In one embodiment, the bottom wall of the packing groove is an inclined surface that slopes from the end away from the receiving groove to the end closer to the receiving groove.

[0009] The pad assembly includes at least two pads with a gap between them, and the filler groove is located directly opposite the gap between the two pads.

[0010] In one embodiment, the barrier structure has two filling grooves, which are located on opposite sides of the barrier structure along the first direction.

[0011] In one embodiment, the barrier structure has four filling grooves, two of which are located on opposite sides of the barrier structure along a first direction, and the other two are located on opposite sides of the barrier structure along a second direction; the second direction is perpendicular to the first direction.

[0012] In some embodiments, the width of the packing groove is 160-200 μm.

[0013] On the other hand, the present invention also provides an LED device, including an LED bracket as described above and a light-emitting chip disposed in the accommodating cavity of the LED bracket. The electrodes of the light-emitting chip are soldered to the pad assembly by solder. A gap space is formed between the bottom surface of the light-emitting chip and the bottom wall of the accommodating cavity. The gap space is filled with a filler material, and the remaining space of the accommodating cavity is filled with fluorescent adhesive.

[0014] In some embodiments, the viscosity of the filler does not exceed 5000 mPa·s.

[0015] In some embodiments, the filler is silicone or white wall adhesive.

[0016] In some embodiments, the light-emitting chip is a flip chip.

[0017] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0018] Figure 1 A 3D view of the existing LED bracket;

[0019] Figure 2 A top view of the existing LED bracket;

[0020] Figure 3 A top view of an existing LED bracket with light-emitting chips installed;

[0021] Figure 4 A cross-sectional view of an existing LED bracket with light-emitting chips mounted on it;

[0022] Figure 5 This is a top view of one embodiment of the LED bracket of this utility model;

[0023] Figure 6 A top view of one embodiment of the LED bracket with a light-emitting chip installed according to this utility model;

[0024] Figure 7 A cross-sectional view of one embodiment of the LED bracket with a light-emitting chip installed according to this utility model;

[0025] Figure 8 This is a top view of another embodiment of the LED bracket of this utility model;

[0026] Figure 9 This is a perspective view of another embodiment of the LED bracket of this utility model.

[0027] Figure label:

[0028] 10. LED bracket; 102. Barrier structure; 104. Receiving groove; 106. Pad assembly; 106A. A-pole pad; 106B. B-pole pad; 1020. Filler groove; 1040. Gap space;

[0029] 20. Light-emitting chip; 201. Electrodes of the light-emitting chip;

[0030] D1, first direction; D2, second direction. Detailed Implementation

[0031] In existing LED brackets, to prevent the metal layer coated on the bottom wall of the LED bracket cavity from deteriorating in conductivity and causing light decay due to oxidation and sulfidation, a barrier structure is usually covered on the bottom wall of the cavity. This barrier structure forms a receiving groove in the middle area of ​​the cup to accommodate the solder pad assembly. The barrier structure is specifically a white adhesive layer. On the one hand, by covering part of the metal layer, the area of ​​the metal layer in contact with air is reduced; on the other hand, by setting up the barrier structure, solder overflow between the light-emitting chip and the solder pad assembly is prevented during the installation of the light-emitting chip. However, in practical applications, LED devices using this type of LED bracket still often experience problems such as light decay during long-term use.

[0032] After studying and analyzing LED devices that experienced light decay, the applicant discovered that the reason for the light decay in LED brackets with the above-mentioned structure is as follows: Figure 3-4 As shown, there is a gap between the bottom surface of the light-emitting chip 20 and the bottom wall of the receiving groove 104, forming a gap space 1040. The height of the pad assembly 106 within the receiving groove 104 generally does not exceed the depth of the receiving groove 104. This causes the bottom surface of the light-emitting chip 20 mounted on the pad assembly 106 to be close to the surface of the barrier structure 102. Thus, the light-emitting chip 20 is essentially covered by the receiving groove 104, preventing the phosphor from filling the gap space 1040 between the light-emitting chip 20 and the bottom wall of the receiving groove 104 during encapsulation. Since air has a lower thermal conductivity than solids, the heat dissipation effect on the bottom surface of the light-emitting chip is poor. With prolonged use, the light-emitting chip is prone to failure, leading to light decay. This is especially true for square light-emitting chips 20, where the gap space 1040 formed by the light-emitting chip 20 and the barrier structure 102 is larger, containing more air and resulting in even worse heat dissipation. For the flip-chip type LED 20, solder paste is required when it is mounted onto the pad assembly 106. The solder paste contains flux. After the soldering is completed, the flux does not completely evaporate. The residual flux will penetrate into the LED 20 through the gap space 1040, affecting the performance of the LED 20 and further aggravating light decay.

[0033] Based on this, the present invention provides a filler groove in the barrier structure 102 that communicates with the receiving groove 104 on which the light-emitting chip 20 is installed. After the light-emitting chip 20 is installed, filler material is injected into the gap space 1040 between the bottom surface of the light-emitting chip 20 and the bottom wall of the receiving groove 104, thereby improving the heat dissipation effect of the bottom surface of the light-emitting chip 20 and reducing the risk of light decay of the device. When the light-emitting chip 20 is soldered to the pad assembly 106, the injected filler material seals the solder connecting the light-emitting chip 20 and the pad assembly 106, thereby preventing the residual combustion promoter in the solder from evaporating when heated and penetrating into the light-emitting chip 20, and further avoiding light decay caused by performance damage of the light-emitting chip 20.

[0034] The present invention will now be described in detail with reference to the accompanying drawings.

[0035] Figure 5-7 The diagram illustrates a specific structure of an exemplary example of the LED bracket of this utility model. For example... Figure 5-7 As shown, in one embodiment of the present invention, the LED bracket 10 has an open receiving cavity, the bottom wall of the receiving cavity is covered with a barrier structure 102, the barrier structure 102 surrounds the receiving cavity to form a receiving groove 104 in the middle position, and the receiving groove 104 is provided with a solder pad assembly 106.

[0036] Specifically, the pad assembly 106 includes at least one A-pole pad 106A and one B-pole pad 106B, which do not contact each other, and the height of both does not exceed the opening of the receiving groove 104. The light-emitting chip 20 is specifically a flip chip, which has two electrodes 201 with opposite polarities, connected to the A-pole pad 106A and the B-pole pad 106B respectively. When the light-emitting chip 20 is mounted on the pad assembly 106, there is a gap 1040 between the bottom surface of the light-emitting chip 20 and the bottom wall of the receiving groove 104. Air exists in the gap space 1040. Air has a low thermal conductivity, resulting in poor heat dissipation of the base plate of the light-emitting chip 20. After long-term use, the light-emitting chip 20 is prone to failure, which in turn causes light decay.

[0037] To improve the heat dissipation effect of the bottom surface of the light-emitting chip 20, the barrier structure 102 is provided with a filling groove 1020 that connects to the receiving groove 104, such as... Figure 6-7 As shown, when the light-emitting chip 20 is mounted on the pad assembly 106, the orthographic projection of the opening of the filler groove 1020 onto the bottom wall of the cup-shaped cavity protrudes beyond the outer periphery of the orthographic projection of the light-emitting chip 20 onto the bottom wall of the cup-shaped cavity. This ensures that the injection needle can be inserted into the opening of the filler groove 1020 when the light-emitting chip 20 is mounted on the pad assembly 106. After the light-emitting chip 20 is soldered and fixed to the pad assembly 106, the filler material is injected into the filler groove 1020 by inserting the injection needle into the filler groove 1020, so that the filler material fills the entire gap space 1040. The filler groove 1020 is preferably positioned directly opposite the gap between two non-contacting pads (such as A-pole pad 106A and B-pole pad 106B), so that the injected filler material can flow in from the gap between the pads, thereby avoiding the pads obstructing the flow of the filler material.

[0038] The bottom of the filling groove 1020 is an inclined surface that slopes from the end away from the receiving groove 104 to the end closer to the receiving groove 104, so as to guide the filler material into the gap space 1040. The width of the filling groove 1020 is 160-200μm. If its width is too small, the filler material will easily clog the filling groove 1020 when it is injected; if the width is too large, the filler material will easily overflow from the filling groove 1020 after filling. In this embodiment, the width of the filling groove 1020 is 180μm. Using a filling groove 1020 of this width can smoothly inject the filler material into the gap space 1040, while avoiding the injected filler material from flowing out of the filling groove 1020. After the filler material filling the gap space 1040 has cured, the remaining space in the receiving cavity is filled with fluorescent glue to complete the encapsulation of the light-emitting chip 20.

[0039] Thus, by injecting filler material into the gap space 1040 through the filler groove 1020 formed in the barrier structure 102, the air in the gap space 1040 is squeezed out, increasing the thermal conductivity within the gap space 1040, thereby improving the heat dissipation effect of the bottom surface of the light-emitting chip 20 and reducing the risk of light decay caused by the failure of the light-emitting chip 20. In addition, the filled filler material can seal the solder connecting the light-emitting chip 20 and the pad assembly 106, preventing residual flux in the solder paste from entering the interior of the light-emitting chip 20, further reducing the risk of light decay caused by the failure of the light-emitting chip 20.

[0040] Here, the filler is a colloid with a certain degree of fluidity at room temperature, and the viscosity of the colloid does not exceed 5000 mPa·s. Specifically, silicone or white wall adhesive with high fluidity at room temperature can be used. The fluidity of the filler facilitates the rapid filling of the gap space 1040 by the injected filler.

[0041] Of course, the LED bracket 10 described above can also have only one filling groove 1020, as long as it is ensured that the filler can be injected into the gap space 1040. However, compared to having only one filling groove 1020, if the LED bracket 10 has two filling grooves 1020, during filling, the injection needle is inserted into one of the filling grooves 1020 to inject filler into the gap space 1040. As the filler is injected, the air in the gap space 1040 is squeezed out from the filling groove 1020 on the other side. In this way, the filling rate can be accelerated and the filler can be filled to the gap space 1040. Both the filling efficiency and the filling effect are obviously better.

[0042] like Figure 8-9As shown, in some embodiments, the barrier structure 102 has four filling grooves 1020, wherein two filling grooves 1020 are located on opposite sides of the barrier structure 102 along the first direction D1, and the other two filling grooves 1020 are located on opposite sides of the barrier structure 102 along the second direction D2, wherein the second direction D2 is perpendicular to the first direction D1. Thus, by providing multiple filling grooves 1020 at relative positions on the barrier structure 102, the filling efficiency is further improved.

[0043] In addition, this utility model also provides an LED device, which includes the above-mentioned LED bracket 10 and a light-emitting chip 20 disposed in the accommodating cavity of the LED bracket 10. The electrodes of the light-emitting chip 20 are soldered to the pad assembly 106 by solder. A gap space 1040 is formed between the bottom surface of the light-emitting chip 20 and the bottom wall of the accommodating cavity. The gap space 1040 is filled with filler material, and the remaining part of the cup accommodating cavity is filled with fluorescent glue.

[0044] Compared to existing technologies, the LED bracket of this invention has a filler groove that communicates with the receiving groove on the barrier structure and is used to install the light-emitting chip. After the light-emitting chip is installed, filler material is injected into the gap between the bottom surface of the light-emitting chip and the bottom wall of the receiving groove. The injected filler material improves the heat dissipation effect of the bottom surface of the light-emitting chip. When the light-emitting chip is soldered to the pad assembly, the injected filler material seals the solder connecting the light-emitting chip and the pad assembly, preventing residual accelerants in the solder from evaporating when heated and penetrating into the light-emitting chip. This avoids light decay caused by performance degradation of the light-emitting chip and effectively improves the service life of the device.

[0045] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of this application. The singular forms “a,” “the,” and “the” used in the embodiments and claims of this application are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that, unless otherwise stated, “a plurality” means two or more; the terms “first,” “second,” “third,” etc., are used only to distinguish and not to describe a particular order or sequence, nor should they be construed as indicating or implying relative importance. The term “and / or” as used herein refers to and includes any or all possible combinations of one or more associated listed items. When the above description relates to drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. In the description of this application, those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0046] The embodiments described above are merely examples of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. An LED bracket having an open receiving cavity, the bottom wall of which is covered by a barrier structure (102), the barrier structure (102) forming a receiving groove (104), the receiving groove (104) having a pad assembly (106) for mounting a light-emitting chip (20), characterized in that: The barrier structure (102) has a filling groove (1020) that connects to the receiving groove (104); when the light-emitting chip (20) is installed on the pad assembly (106), the orthographic projection of the groove opening of the filling groove (1020) on the bottom wall of the receiving cavity protrudes beyond the outer periphery of the orthographic projection of the light-emitting chip (20) on the bottom wall of the receiving cavity.

2. The LED bracket according to claim 1, characterized in that: The bottom wall of the filling trough (1020) is an inclined surface that slopes from the end away from the receiving trough (104) to the end close to the receiving trough (104).

3. The LED bracket according to claim 1, characterized in that: The pad assembly (106) includes at least two pads with a gap between them, and the filler groove (1020) is located opposite the gap between the two pads.

4. The LED bracket according to claim 1, characterized in that: The barrier structure (102) has two filling grooves (1020), which are located on opposite sides of the barrier structure (102) along the first direction.

5. The LED bracket according to claim 1, characterized in that: The barrier structure (102) has four filling grooves (1020), two of which are located on opposite sides of the barrier structure (102) along the first direction, and the other two are located on opposite sides of the barrier structure (102) along the second direction. The second direction is perpendicular to the first direction.

6. The LED bracket according to claim 1, characterized in that: The width of the packing groove (1020) is 160-200μm.

7. An LED device, characterized in that: The device includes an LED bracket (10) as described in any one of claims 1 to 6 and a light-emitting chip (20) disposed in the accommodating cavity of the LED bracket (10). The electrodes (201) of the light-emitting chip (20) are soldered to the pad assembly by solder. A gap space (1040) is formed between the bottom surface of the light-emitting chip (20) and the bottom wall of the accommodating cavity. The gap space (1040) is filled with filler material, and the remaining space of the accommodating cavity is filled with fluorescent adhesive.

8. The LED device according to claim 7, characterized in that: The viscosity of the filler does not exceed 5000 mPa·s.

9. The LED device according to claim 7, characterized in that: The filler is silicone or white wall adhesive.

10. The LED device according to claim 7, characterized in that: The light-emitting chip (20) is a flip chip.

Images