Lamp bead structure and preparation method thereof

Abstract

The invention provides a lamp bead structure and a preparation method thereof.The lamp bead structure comprises a support and a stretching part arranged on the support, the stretching part is in a sawtooth shape, the surface of the support is sequentially electroplated with a first metal layer and a second metal layer, the outer side of the stretching part is wrapped with PPA used for supporting the stretching part, and the first metal layer and the second metal layer are arranged on the support. The top of the support is provided with an R chip, a G chip and a B chip, surface electrodes of the R chip, the G chip and the B chip are bonded with corresponding metal parts at the top of the support through bonding wires, and the outer sides of the support and the PPA are further wrapped with packaging glue.

Description

Technical Field

[0001] The invention relates to the technical field of LEDs, and in particular to a lamp bead structure and a preparation method thereof. Background Art

[0002] With the widespread application of display technology, the application scenarios have also become more diversified, and the application of LED display devices, the key components of display screens, has become more important. Therefore, the reliability performance requirements of lamp beads are getting higher and higher. From the perspective of LED lamp bead technology, packaging technology and product structure have an important impact on its performance and reliability.

[0003] In the prior art, with the demand for viewing of LED display screens, LED display screens are required to have a large angle, good contrast consistency effect, and higher brightness. The existing TOP LED devices use TOP stamping injection molding brackets as brackets. The brackets are divided into front and back sides. The front side is composed of PPA and the metal part after stamping and stretching as the functional area of ​​the lamp beads. The PPA part is formed into a bowl cup by injection molding to protect the functional area, but the lamp bead bowl cup will cause the lamp bead angle to be small and the chip brightness will be lost. The back side is composed of PPA and pins. The pins are formed after bending. Due to the folding process of the lamp bead feet, there is a height difference in the folding feet of the lamp bead, resulting in poor consistency of the display screen surface after the LED lamp bead is mounted; the front functional area uses silver glue or insulating glue to fix the chip in the functional area. The bonding wires are welded to the chip electrodes and functional areas to form an electrical connection between the chip and the functional areas. The bracket is sealed with glue through the glue dispensing process, and then the materials are blanked into RGB three-primary color lamp beads. Due to the glue dispensing packaging process, there are differences in the packaging glue of the lamp beads, which will also lead to poor surface consistency of the display screen after the LED lamp beads are mounted. In addition, due to the increasingly higher market requirements and the increasingly diverse use environments, especially under conditions of heavy humidity, water vapor can easily penetrate under the current technical solutions, causing the lamp beads to burn out and even form caterpillars in severe cases. Therefore, the requirements for the airtightness of the product are also getting higher and higher. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide a lamp bead structure and a preparation method thereof, which can effectively solve the deficiencies in the above-mentioned prior art.

[0005] A lamp bead structure comprises a bracket and a stretching portion arranged on the bracket, the stretching portion is serrated, a first metal layer and a second metal layer are electroplated in sequence on the surface of the bracket, a PPA in the shape of a square prism is wrapped on the outside of the stretching portion for supporting the stretching portion, an R chip, a G chip and a B chip are arranged on the top of the bracket, the surface electrodes of the R chip, the G chip and the B chip are bonded to the corresponding metal parts on the top of the bracket by bonding wires, and packaging glue is molded and covered on the periphery of the bracket and the PPA.

[0006] Furthermore, the thickness of the bracket is 0.1mm-0.2mm, and the width of the bracket is 70mm-75mm.

[0007] Furthermore, the stretching height of the stretching portion is 0.05mm-0.09mm.

[0008] Furthermore, the first metal layer is nickel metal with a thickness of 10um-20um, and the second metal layer is silver metal with a thickness of 20um-40um.

[0009] Furthermore, an injection hole and a MARK point are arranged at the bottom of the PPA, the injection hole is arranged at the center of the bottom of the PPA, and the MARK point is arranged at one side of the injection hole.

[0010] On the other hand, the present invention also provides a method for preparing a lamp bead structure, the preparation method comprising:

[0011] S1, preparation of scaffolds;

[0012] S2, electroplating the support;

[0013] S3, injection molding the electroplated stent;

[0014] S4, performing die bonding on the injection molded stent;

[0015] S5, performing the first baking on the bracket after the die bonding;

[0016] S6, performing the first cleaning on the baked stent;

[0017] S7, welding the cleaned bracket;

[0018] S8, cleaning the bracket for the second time after the wire welding;

[0019] S9, performing molding and packaging on the stent after the second cleaning;

[0020] S10, baking the molded and packaged bracket for the second time;

[0021] S11, cutting the bracket after the second baking into lamp beads;

[0022] Among them, the lamp bead structure includes a bracket and a stretching part arranged on the bracket, the stretching part is serrated, and the first metal layer and the second metal layer are electroplated in sequence on the surface of the bracket, and a square prism-shaped PPA is wrapped on the outside of the stretching part to support the stretching part. An R chip, a G chip and a B chip are arranged on the top of the bracket, and the surface electrodes of the R chip, the G chip and the B chip are bonded to the corresponding metal parts on the top of the bracket through bonding wires, and the bracket and the PPA are molded and covered with packaging glue.

[0023] Furthermore, the specific process of first baking the bracket after die bonding is as follows:

[0024] The glue used to fix the R chip, the G chip and the B chip is cured by baking in a tunnel furnace, wherein the curing conditions of the glue used to fix the R chip, the G chip and the B chip are baking at 140° C.-180° C. for two hours.

[0025] Furthermore, the specific process of welding the cleaned bracket is as follows:

[0026] The bonding wires are used to bond the surface electrodes of the R chip, the G chip and the B chip to the corresponding metal parts on the top of the bracket through a wire bonding machine, so that the R chip, the G chip and the B chip are electrically connected to the lamp bead pins respectively.

[0027] Furthermore, the specific process of molding and packaging the bracket after the second cleaning is as follows:

[0028] The product after the welding wire is encapsulated by the encapsulation glue from the top, front, back, left and right sides through the molding machine and the molding mold.

[0029] Furthermore, the specific process of baking the bracket after molding and packaging for the second time is as follows:

[0030] The encapsulation glue is cured by baking at 110°C-150°C for 1 hour in a tunnel oven and then baking at 130°C-170°C for 4 hours.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows: by arranging a stretching portion on the bracket and the stretching portion is in a serrated shape, when the serrated stretching portion is electroplated and then PPA is injected, the bonding with PPA can be increased, so that PPA and the bracket are more tightly bonded, and the path for water vapor to penetrate along the side of the metal strip is extended, thereby improving the overall air tightness of the lamp bead; by molding and covering the encapsulation glue on the bracket and the periphery of PPA, the surface molding consistency of the lamp bead is very good, thereby avoiding the burning of the lamp bead and metal migration due to poor air tightness of the encapsulation glue and the bracket, improving the overall performance of the lamp bead, and at the same time improving the consistency of the display screen and The light-emitting angle of the lamp beads can reduce the impact of bowls and cups on brightness and angle, thereby further improving the brightness and light-emitting angle of the lamp beads, making the display effect of the display screen brighter, with a larger angle and a more delicate display effect; the overall packaging process of the lamp beads reduces the pin bending process, so that the height of the lamp body and the horizontality of the pins are improved, and the consistency of the later lamp bead patch display screen is improved, so that the display module can be made thinner and more beautiful, while reducing the damage caused by bending force and improving the airtightness of the lamp beads; this design method and process flow simplifies the process flow, improves production efficiency, and greatly reduces the cost of lamp beads. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a flow chart of a method for preparing a lamp bead structure in an embodiment of the present invention;

[0033] Figure 2 It is a cross-sectional schematic diagram of the lamp bead structure in an embodiment of the present invention;

[0034] Figure 3 A schematic top view of a lamp bead structure in an embodiment of the present invention;

[0035] Figure 4 It is a bottom view schematic diagram of the lamp bead structure in an embodiment of the present invention;

[0036] Description of main component symbols:

[0037] Bracket 1 Bonding wire 6 PPA 2 Encapsulation glue 7 R chip 3 Stretching part 8 G chip 4 Injection hole 9 B chip 5 MARK point 10

[0038] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0039] In order to facilitate understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0040] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0042] Example 1

[0043] See also Figures 1 to 4 The embodiment of the present invention provides a method for preparing a lamp bead structure, and the preparation method comprises the following steps:

[0044] S1, preparation of scaffold 1;

[0045] The specific process for preparing the stent 1 is as follows:

[0046] A copper metal strip or an iron metal strip with a thickness of 0.1mm-0.2mm and a width of 70mm-75mm is used to form a designed structure by punching and stretching, and the stretching height is 0.05mm-0.09mm. During the punching, a serrated shape is punched at the stretching portion 8;

[0047] It should be noted that in this embodiment, a copper metal strip with a thickness of 0.15 mm and a width of 72 mm is stretched into a designed structure, and the stretching height is 0.07 mm.

[0048] It can be understood that by stamping the stretching portion 8 into a serrated shape, when the bracket 1 is injection molded with the PPA2 after subsequent electroplating, the PPA2 can be more closely combined with the metal strip, extending the water vapor penetration path along the side of the metal strip, and at the same time increasing the bonding of the metal strip, thereby improving the overall airtightness of the lamp bead.

[0049] S2, electroplating the support 1;

[0050] Furthermore, the specific process of electroplating the bracket 1 is as follows:

[0051] A layer of nickel metal with a thickness of 10um to 20um as a first metal layer and a layer of silver metal with a thickness of 20um to 40um as a second metal layer are sequentially electroplated on the surface of the bracket through a nickel-on-silver electroplating process.

[0052] S3, injection molding the electroplated stent;

[0053] The specific process of injection molding the electroplated bracket is as follows:

[0054] The electroplated bracket is wrapped with PPA2 through an injection molding machine and a specific injection mold, so that the stretching portion 8 of the electroplated bracket is supported, and the PPA2 is formed into a square prism shape during injection molding.

[0055] It should be noted that during injection molding, the PPA2 can be black PPA or white PPA.

[0056] It can be understood that during injection molding, the PPA2 forms a square prism shape instead of a bowl-shaped shape; since there is no bowl-shaped shape, there are no restrictions during the subsequent die bonding and wire bonding, which greatly improves the efficiency of the die bonding and wire bonding.

[0057] S4, performing die bonding on the injection molded stent;

[0058] Furthermore, the specific process of performing die bonding on the injection molded bracket is as follows:

[0059] The R chip 3, the G chip 4 and the B chip 5 are fixed on the top of the injection-molded bracket by a die-bonding machine, wherein the R chip 3 is fixed by die-bonding silver glue, and the G chip 4 and the B chip 5 are fixed by die-bonding insulating glue.

[0060] S5, performing the first baking on the bracket after the die bonding;

[0061] Furthermore, the specific process of first baking the bracket after die bonding is as follows:

[0062] The glue used to fix the R chip 3, the G chip 4 and the B chip 5 is cured by baking in a tunnel furnace, wherein the curing conditions of the glue used to fix the R chip 3, the G chip 4 and the B chip 5 are baking at 140°C-180°C for two hours.

[0063] S6, performing the first cleaning on the baked stent;

[0064] Furthermore, the specific process of first cleaning the baked stent is as follows:

[0065] The first cleaning of the bracket after the first baking is carried out by a plasma cleaning machine.

[0066] It can be understood that the baked bracket is cleaned by a plasma cleaning machine to make the surface cleaner and facilitate wire welding.

[0067] S7, welding the cleaned bracket;

[0068] Furthermore, the specific process of welding the cleaned bracket is as follows:

[0069] The bonding wire 6 is used to bond the surface electrodes of the R chip 3, the G chip 4 and the B chip 5 to the corresponding metal parts on the top of the bracket 1 through a wire bonding machine, so that the lamp bead pins of the R chip 3, the G chip 4 and the B chip 5 are electrically connected.

[0070] S8, cleaning the bracket for the second time after the wire welding;

[0071] Furthermore, the specific process for performing a second cleaning on the bracket after wire welding is as follows:

[0072] The bracket after the wire welding is cleaned for the second time by a plasma cleaning machine.

[0073] It can be understood that the second cleaning of the bracket after the wire bonding is performed by a plasma machine, so that the surface of the bracket after the wire bonding is cleaner, thereby making the packaging glue 7 and the surface of the bracket after the wire bonding more tightly combined during the subsequent molding packaging.

[0074] S9, performing molding and packaging on the stent after the second cleaning;

[0075] Furthermore, the specific process of molding and packaging the bracket after the second cleaning is as follows:

[0076] The product after the welding wire is encapsulated by the encapsulation glue from the top, front, back, left and right sides through the molding machine and the molding mold.

[0077] S10, baking the molded and packaged bracket for the second time;

[0078] Furthermore, the specific process of baking the bracket after molding and packaging for the second time is as follows:

[0079] The encapsulation glue is cured by baking at 110°C-150°C for 1 hour in a tunnel oven and then baking at 130°C-170°C for 4 hours.

[0080] S11, cutting the bracket after the second baking into lamp beads.

[0081] Furthermore, after the bracket is cut into lamp beads after the second baking, it is used for photoelectric parameter classification by a spectrometer. The classification is carried out according to the brightness ratio of 1.3, the wavelength of 5nm, and the voltage of 0.6V. Then, the lamp beads are taped and packaged in a unified direction by a taping machine for shipment.

[0082] It can be understood that by punching the stretching portion 8 of the metal strip into a serrated shape, so that when the strip is electroplated with a serrated metal strip and then the PPA2 is injected, the PPA2 and the metal strip are more tightly combined, extending the water vapor penetration path along the side of the metal strip, and at the same time, the bonding of the metal strip can be increased, thereby improving the overall air tightness of the lamp bead; by forming a square prism shape during the injection molding of the PPA2 instead of a bowl-cup shape, there is no restriction during the subsequent crystal bonding and wire welding, which greatly improves the efficiency of crystal bonding and wire welding, saves the amount of PPA2, and improves the air tightness performance of the lamp bead; the molding process is used to make the encapsulation glue wrap the five sides of the protective lamp bead, and the surface molding consistency of the molded encapsulation glue lamp bead is very good, thereby avoiding the encapsulation glue The water 7 and the bracket 1 have poor air tightness, which causes the lamp beads to burn out and metal to migrate, thereby improving the overall performance of the lamp beads, while also improving the consistency of the display screen and the luminous angle of the lamp beads, and reducing the impact of bowls and cups on brightness and angle, thereby further improving the brightness of the lamp beads and the luminous angle, making the display effect of the display screen brighter, with a larger angle and a more delicate display effect; in the overall packaging process of the lamp beads, the lamp bead body height and pin horizontality are improved because the lamp beads reduce the pin bending process, and the consistency of the later lamp bead patch display screen is improved, so that the display screen module can be made thinner and more beautiful, while reducing damage caused by bending force and improving the air tightness of the lamp beads; this design method and process flow simplifies the process flow, improves production efficiency, and greatly reduces the cost of lamp beads.

[0083] See also Figures 2 - 4 , shown are a cross-sectional schematic diagram, a top view schematic diagram and a bottom view schematic diagram of a lamp bead prepared by the method for preparing a lamp bead structure in an embodiment of the present invention.

[0084] In summary, the lamp bead structure and preparation method thereof in the above-mentioned embodiments of the present invention, by setting a stretching portion on the bracket and the stretching portion is in a serrated shape, so that when the serrated stretching portion is electroplated and then PPA is injected, the bonding with PPA can be increased, so that PPA and the bracket are more tightly bonded, and the path for water vapor to penetrate along the side of the metal strip is extended, thereby improving the overall air tightness of the lamp bead; by molding and covering the packaging glue on the bracket and the periphery of PPA, the surface molding consistency of the lamp bead is very good, thereby avoiding the burning of the lamp bead and metal migration due to poor air tightness of the packaging glue and the bracket, improving the overall performance of the lamp bead, and at the same time improving the consistency of the display screen The brightness and luminous angle of the lamp beads can be improved, and the influence of the bowl and cup on the brightness and angle can be reduced, thereby further improving the brightness and luminous angle of the lamp beads, making the display effect of the display screen brighter, with a larger angle and a more delicate display effect; the overall packaging process of the lamp beads reduces the pin bending process, so that the height of the lamp body and the horizontality of the pins are improved, and the consistency of the lamp bead patch display screen is improved in the later stage, so that the display module can be made thinner and more beautiful, while reducing the damage caused by the bending force and improving the airtightness of the lamp beads; this design method and process flow simplifies the process flow, improves production efficiency, and greatly reduces the cost of lamp beads.

[0085] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", 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 invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0086] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A lamp bead structure, characterized in that: It includes a bracket and a stretching part arranged on the bracket, the stretching part is serrated, and a first metal layer and a second metal layer are electroplated in sequence on the surface of the bracket, a square prism-shaped PPA is wrapped on the outside of the stretching part for supporting the stretching part, an R chip, a G chip and a B chip are arranged on the top of the bracket, and the surface electrodes of the R chip, the G chip and the B chip are bonded to the corresponding metal parts on the top of the bracket through bonding wires, and the bracket and the PPA are molded and covered with packaging glue.

2. The lamp bead structure according to claim 1, characterized in that: The thickness of the bracket is 0.1mm-0.2mm, and the width of the bracket is 70mm-75mm.

3. The lamp bead structure according to claim 1, characterized in that: The stretching height of the stretching part is 0.05mm-0.09mm.

4. The lamp bead structure according to claim 1, characterized in that: The first metal layer is nickel metal with a thickness of 10um-20um, and the second metal layer is silver metal with a thickness of 20um-40um.

5. The lamp bead structure according to claim 1, characterized in that: An injection hole and a MARK point are arranged at the bottom of the PPA. The injection hole is arranged at the center of the bottom of the PPA, and the MARK point is arranged at one side of the injection hole.

6. A method for preparing a lamp bead structure, characterized in that: The preparation method comprises: S1, preparation of scaffolds; S2, electroplating the support; S3, injection molding the electroplated stent; S4, performing die bonding on the injection molded stent; S5, performing the first baking on the bracket after the die bonding; S6, performing the first cleaning on the baked stent; S7, welding the cleaned bracket; S8, cleaning the bracket for the second time after the wire welding; S9, performing molding and packaging on the stent after the second cleaning; S10, baking the molded and packaged bracket for the second time; S11, cutting the bracket after the second baking into lamp beads; Among them, the lamp bead structure includes a bracket and a stretching part arranged on the bracket, the stretching part is serrated, and the first metal layer and the second metal layer are electroplated in sequence on the surface of the bracket, and a square prism-shaped PPA is wrapped on the outside of the stretching part to support the stretching part. An R chip, a G chip and a B chip are arranged on the top of the bracket, and the surface electrodes of the R chip, the G chip and the B chip are bonded to the corresponding metal parts on the top of the bracket through bonding wires, and the bracket and the PPA are molded and covered with packaging glue.

7. The method for preparing a lamp bead structure according to claim 6, characterized in that: The specific process of the first baking of the bracket after die bonding is as follows: The glue used to fix the R chip, the G chip and the B chip is cured by baking in a tunnel furnace, wherein the curing conditions of the glue used to fix the R chip, the G chip and the B chip are baking at 140° C.-180° C. for two hours.

8. The method for preparing a lamp bead structure according to claim 6, characterized in that: The specific process of welding the cleaned bracket is as follows: The bonding wires are used to bond the surface electrodes of the R chip, the G chip and the B chip to the corresponding metal parts on the top of the bracket through a wire bonding machine, so that the R chip, the G chip and the B chip are electrically connected to the lamp bead pins respectively.

9. The method for preparing a lamp bead structure according to claim 6, characterized in that: The specific process of molding and packaging the bracket after the second cleaning is as follows: The product after the welding wire is encapsulated by the encapsulation glue from the top, front, back, left and right sides through the molding machine and the molding mold.

10. The method for preparing a lamp bead structure according to claim 6, characterized in that: The specific process of baking the bracket for the second time after molding is as follows: The encapsulation glue is cured by baking at 110°C-150°C for 1 hour in a tunnel oven and then baking at 130°C-170°C for 4 hours.

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