Light source powder spraying method for improving product yield

Abstract

The present invention relates to the technical field of light sources, and discloses a light source powder spraying method for improving the product yield, which includes the following steps: providing a substrate having a light-emitting area, die-bonding on the light-emitting area to form a plurality of warm white light-emitting chips and positive white light-emitting chips; providing a template having a plurality of hollow grooves that penetrate the template up and down; the outer periphery of the hollow groove protrudes outward to form four outer convex grooves; arranging a dam on the substrate, and the dam encloses the outer periphery of the light-emitting area, and the light-emitting area encloses to form an enclosed area; spraying a second fluorescent glue layer in the enclosed area; by covering the template on the plurality of warm white light-emitting chips, the hollow grooves are arranged in an up-and-down alignment with the warm white light-emitting chips, and the four outer convex grooves are respectively aligned with the four end corners of the warm white light-emitting chips, and then spraying the first fluorescent glue layer on the light-emitting chips, so that there is a certain space distance between the warm white light-emitting chips, and it is ensured that the entire warm white light-emitting chip is evenly covered by the first fluorescent glue layer, thus improving the finished product yield.

Description

Technical Field

[0001] The present invention relates to the technical field of light sources, and more specifically, to a powder spraying method for light sources to improve the product yield. Background Art

[0002] A light source is a light-emitting element in various lamps. The light source includes a substrate, on which there is a light-emitting area. A light-emitting chip is die-bonded on the light-emitting area, and glue is dispensed on the light-emitting area to form a fluorescent glue layer, which covers the light-emitting chip. The light emitted by the light-emitting chip then transmits through the fluorescent glue layer.

[0003] For some light sources that need to emit positive white light and warm white light, after die-bonding the light-emitting chips on the light-emitting area, wire bonding is performed to electrically connect the light-emitting chips to the pads of the substrate. Then, a first fluorescent glue layer is sprayed on some of the light-emitting chips, and a dam is set around the light-emitting area. Then, a second fluorescent glue layer is dot-coated in the dam. In this way, multiple light-emitting chips can emit positive white light and warm white light respectively.

[0004] In the prior art, during the process of spraying the first fluorescent glue layer, a template is covered on multiple light-emitting chips. The template is provided with a plurality of hollow holes, and through the hollow holes, the first fluorescent glue layer is sprayed on the light-emitting chips. However, since the light-emitting chips are square-shaped, during the process of spraying the first fluorescent glue layer, the four corner positions of the light-emitting chips are insufficiently covered by the first fluorescent glue layer, resulting in a high defect rate of the light source. Summary of the Invention

[0005] The present invention provides a powder spraying method for light sources to improve the product yield, aiming to solve the problem of high defect rate of light sources in the prior art.

[0006] The present invention is implemented as follows. The powder spraying method for light sources to improve the product yield includes the following steps:

[0007] 1) Provide a substrate, the substrate has a light-emitting area, and die-bonding is performed in the light-emitting area to form a plurality of warm white light-emitting chips and positive white light-emitting chips arranged at intervals. The warm white light-emitting chips and the positive white light-emitting chips are respectively square-shaped;

[0008] 2) Perform wire bonding to electrically connect the plurality of warm white light-emitting chips and the plurality of positive white light-emitting chips to the pads in the substrate through wires;

[0009] 3), Provide a template with a plurality of hollow grooves that penetrate the template vertically; the outer periphery of the hollow groove protrudes outward to form four outer convex grooves, and a plurality of the outer convex grooves penetrate the template vertically; place the template on the substrate, and align the hollow groove with the warm white light-emitting chip vertically; the outer periphery of the hollow groove is arranged offset from the outer periphery of the warm white light-emitting chip, and a plurality of the outer convex grooves are respectively aligned with the four end corners of the warm white light-emitting chip;

[0010] Spray a first fluorescent glue layer through the hollow groove and the outer convex groove of the template, and the first fluorescent glue layer covers the warm white light-emitting chip;

[0011] 4), Set a dam on the substrate, and the dam encloses the outer periphery of the light-emitting area, and the light-emitting area encloses a surrounding area;

[0012] 5), Spray a second fluorescent glue layer in the surrounding area, and the second fluorescent glue layer covers the warm white light-emitting chip, the first fluorescent glue layer and the white light-emitting chip.

[0013] Optionally, in step 5), when the second fluorescent glue layer is cured to form a light source, place the light source in a spectrometer for spectral screening.

[0014] Optionally, in step 5), after the light source is spectrally screened by the spectrometer, it is packaged and stored in the warehouse.

[0015] Optionally, in step 3), after the warm white light-emitting chip is sprayed with the first fluorescent glue layer, place the substrate in a baking oven and bake until the first fluorescent glue layer is cured.

[0016] Optionally, in step 5), after spraying the second fluorescent glue layer in the surrounding area, place the substrate in a baking oven and bake until the second fluorescent glue layer is cured.

[0017] Optionally, the outer periphery of the hollow groove has an arc segment located between adjacent outer convex grooves, and the arc segment protrudes and bends outwardly offset from the hollow groove.

[0018] Optionally, along the direction from the inside to the outside of the outer convex groove, the width of the outer convex groove gradually decreases.

[0019] Optionally, the inner end of the outer convex groove communicates with the hollow groove, and the outer end of the outer convex groove is in a pointed shape.

[0020] Optionally, in step 3, spray the first fluorescent glue layer on the template through a spray head;

[0021] The spray head is connected to the glue delivery pipe. A horizontally arranged extrusion cavity is provided in the spray head. A plurality of glue inlet holes for the first fluorescent glue layer to pass through are formed at the rear end of the extrusion cavity, and the plurality of glue inlet holes are arranged at intervals along the horizontal direction of the extrusion cavity; a flat glue spraying port is formed at the front end of the extrusion cavity, and the glue spraying port extends along the horizontal direction of the extrusion cavity;

[0022] Along the direction from the rear to the front of the extrusion cavity, the extrusion cavity is large in the middle and small at both ends; two elastic film layers are provided in the extrusion cavity, the two film layers are arranged oppositely and are respectively located on both sides of the glue spraying port, and a glue containing space is enclosed between the two film layers; both ends of the film layer are fixedly connected to the inner side wall of the extrusion cavity, and there is a deformation space between the middle part of the film layer and the inner side wall of the extrusion cavity; air inlet holes are respectively provided on both sides of the spray head, the air inlet holes are communicated with the deformation space, and the air inlet holes are connected to a blower through a pipeline;

[0023] In step 3), during the process of transporting the first fluorescent glue layer to the glue containing space through the glue delivery pipe, the blower injects gas with a set pressure into the deformation space through the pipeline, driving the film layer to deform towards the glue containing space, and at the same time squeezing the first fluorescent glue layer in the glue containing space to be continuously extruded from the glue spraying port, and spraying the first fluorescent glue layer extruded through the glue spraying port onto the template. The first fluorescent glue layer passes through the hollowed-out grooves and the outward convex grooves to form a first fluorescent glue layer covering the warm white chip.

[0024] Optionally, the film layer includes a plurality of thick film segments and a plurality of thin film segments. Along the direction from the rear end to the front end of the extrusion cavity, the thick film segments and the thin film segments are staggered and butted in sequence, and the width of the thin film segments gradually increases; the thickness of the rear end of the thick film segment is greater than that of the thin film segment, and the anti-deformation strength of the thick film segment is greater than that of the thin film segment;

[0025] In step 3), during the process of the blower injecting gas with a set pressure into the deformation space through the pipeline, the range of the thin film segment protruding and deforming towards the glue containing space is greater than the range of the thick film segment protruding and deforming towards the glue containing space, and the deformation speed of the thin film segment is greater than that of the thick film segment.

[0026] Compared with the prior art, the present invention provides a light source powder spraying method for improving the product yield. By covering a template on a plurality of warm white light-emitting chips, the hollowed-out grooves are arranged vertically aligned with the warm white light-emitting chips, and the four outward convex grooves are respectively aligned with the four end corners of the warm white light-emitting chips, and then spraying the first fluorescent glue layer on the light-emitting chips. In this way, it not only meets the requirement of a certain space distance between the warm white light-emitting chips, but also ensures that the entire warm white light-emitting chip is evenly covered by the first fluorescent glue layer, improving the finished product yield. Description of the Drawings

[0027] Figure 1It is a front view schematic diagram of the substrate provided by the present invention;

[0028] Figure 2 It is a front view schematic diagram of the template provided by the present invention;

[0029] Figure 3 It is a sectional view schematic diagram of the spray head provided by the present invention;

[0030] Figure 4 It is a sectional view schematic diagram of the spray head provided by the present invention. Specific embodiments

[0031] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0033] In the drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and cannot be understood as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0034] Refer to Figures 1-4 As shown, it is a preferred embodiment provided by the present invention.

[0035] The light source powder spraying method for improving the product yield provided by the present invention includes the following steps:

[0036] 1), Provide a substrate 100, the substrate 100 has a light-emitting area, and die bonding is performed in the light-emitting area to form a plurality of warm white light-emitting chips 101 and positive white light-emitting chips 102 arranged at intervals, and the warm white light-emitting chips 101 and the positive white light-emitting chips 102 are respectively square;

[0037] 2), Perform wire bonding to electrically connect a plurality of warm white light-emitting chips 101 and a plurality of positive white light-emitting chips 102 to the pads in the substrate 100 through wires;

[0038] 3) Provide a template 200 with multiple hollow slots 201. The hollow slots 201 penetrate the template 200 vertically; the outer periphery of the hollow slot 201 protrudes outward to form four outer protruding slots 202, and the multiple outer protruding slots 202 penetrate the template 200 vertically; place the template 200 on the substrate 100, and align the hollow slot 201 with the warm white light-emitting chip 101 vertically; the outer periphery of the hollow slot 201 is arranged offset from the outer periphery of the warm white light-emitting chip 101, and the multiple outer protruding slots 202 are respectively aligned with the four end corners of the warm white light-emitting chip 101;

[0039] Through the hollow slots 201 and the outer protruding slots 202 of the template 200, spray a first fluorescent glue layer 103, and the first fluorescent glue layer 103 covers the warm white light-emitting chip 101;

[0040] 4) Set a dam 104 on the substrate 100. The dam 104 surrounds the outer periphery of the light-emitting area, and the light-emitting area encloses an enclosed area;

[0041] 5) Spray a second fluorescent glue layer 105 in the enclosed area. The second fluorescent glue layer 105 covers the warm white light-emitting chip 101, the first fluorescent glue layer 103, and the positive white light-emitting chip 102.

[0042] The above-provided light source powder spraying method for improving product yield, by using the template 200 to cover multiple warm white light-emitting chips 101, aligning the hollow slot 201 with the warm white light-emitting chip 101 vertically, and aligning the four outer protruding slots 202 with the four end corners of the warm white light-emitting chip 101 respectively, and then spraying the first fluorescent glue layer 103 on the light-emitting chip. In this way, it not only satisfies a certain spatial distance between the warm white light-emitting chips 101, but also ensures that the entire warm white light-emitting chip 101 is evenly covered by the first fluorescent glue layer 103, improving the finished product yield.

[0043] In step 5), when the second fluorescent glue layer 105 is cured, a light source is formed, and the light source is placed in a spectrometer for spectral screening. In this way, the spectrometer can classify and screen the wavelength, light intensity, and current voltage magnitude of the light emitted by the light source.

[0044] In step 5), after the light source is spectrally screened by the spectrometer, it is packed and stored in the warehouse. In this way, after screening, the screened light sources are packed to ensure the correct distribution of different types of products.

[0045] In step 3), after the first fluorescent glue layer 103 is sprayed on the warm white light-emitting chip 101, place the substrate 100 in a baking oven for baking until the first fluorescent glue layer 103 is cured. In this way, it is avoided that the second fluorescent glue layer 105 is mixed into the first fluorescent glue layer 103 in subsequent processes, and it is also avoided that foreign substances are mixed into the uncured first fluorescent glue layer 103.

[0046] In step 5), after spraying the second fluorescent glue layer 105 on the surrounding area, the substrate 100 is placed in a baking machine for baking until the second fluorescent glue layer 105 is cured. In this way, it takes a long time to wait for solidification in the air, and the baking machine dries it quickly to avoid impurities mixing into the second fluorescent glue layer 105.

[0047] The outer periphery of the hollow groove 201 has an arc segment 203 located between adjacent outer convex grooves 202, and the arc segment 203 bulges and bends outwardly deviating from the hollow groove 201. In this way, during the process of spraying the first fluorescent glue layer 103, a sufficiently large spraying area can be ensured around the warm white light-emitting chip 101.

[0048] Along the direction from the inside to the outside of the outer convex groove 202, the width of the outer convex groove 202 gradually decreases. Since the warm white light-emitting chip 101 is square-shaped, and during the spraying process, the four outer convex grooves 202 are respectively aligned with the four end corners of the warm white light-emitting chip 101. Along the direction from the inside to the outside of the outer convex groove 202, the width of the end corner gradually decreases. In this way, while ensuring that the entire warm white light-emitting chip 101 can be evenly covered by the first fluorescent glue layer 103, a certain spatial distance between the warm white light-emitting chips 101 is also satisfied.

[0049] The inner end of the outer convex groove 202 communicates with the hollow groove 201, and the outer end of the outer convex groove 202 is in a pointed shape. In this way, when the square warm white light-emitting chip 101 is placed in the hollow groove 201, its end corners can be placed in the outer convex grooves 202.

[0050] In step 3, the first fluorescent glue layer 103 is sprayed on the template 200 through the spray head 300.

[0051] The spray head 300 is connected to a glue delivery pipe. The spray head 300 is provided with a horizontally arranged extrusion cavity 301. A plurality of glue inlet holes 302 for the first fluorescent glue layer 103 to pass through are formed at the rear end of the extrusion cavity 301, and the plurality of glue inlet holes 302 are arranged at intervals along the horizontal direction of the extrusion cavity 301; a flat glue spraying port 303 is formed at the front end of the extrusion cavity 301, and the glue spraying port 303 extends along the horizontal direction of the extrusion cavity 301.

[0052] Along the direction from the rear to the front of the extrusion cavity 301, the extrusion cavity 301 is in a shape that is large in the middle and small at both ends; two elastic film layers 304 are provided in the extrusion cavity 301. The two film layers 304 are arranged oppositely and are respectively located on both sides of the glue spraying port 303. A glue containing space is enclosed between the two film layers 304; both ends of the film layer 304 are fixedly connected to the inner side wall of the extrusion cavity 301, and there is a deformation space 305 between the middle part of the film layer 304 and the inner side wall of the extrusion cavity 301; air inlet holes 306 are respectively provided on both sides of the spray head 300, the air inlet holes 306 communicate with the deformation space 305, and the air inlet holes 306 are connected to a blower through a pipeline 307.

[0053] In step 3), during the process of transporting the first fluorescent glue layer 103 to the glue-containing space through the glue delivery tube, the blower injects gas with a set pressure into the deformation space 305 through the pipeline 307, driving the film layer 304 to deform towards the glue-containing space. At the same time, the first fluorescent glue layer 103 in the glue-containing space is extruded continuously through the glue spraying port 303 under extrusion, and the first fluorescent glue layer 103 extruded through the glue spraying port 303 is sprayed onto the template 200. The first fluorescent glue layer 103 passes through the hollow grooves 201 and the convex grooves 202 to form the first fluorescent glue layer 103 covering the warm white chip.

[0054] During the spraying process of the first fluorescent glue layer 103, when the first fluorescent glue layer 103 is injected into the glue-containing space and extruded towards the glue spraying port 303, the film layer 304 is also deformed towards the glue-containing space under the drive of the gas with a set pressure at the same time, squeezing the first fluorescent glue in the glue-containing space, making the first fluorescent glue in the glue-containing space more dense, and the first fluorescent glue sprayed out from the glue spraying port 303 is sprayed continuously.

[0055] The film layer 304 includes a plurality of thick film segments 3040 and a plurality of thin film segments 3041. Along the direction from the rear end to the front end of the extrusion cavity 301, the thick film segments 3040 and the thin film segments 3041 are staggeredly butted in sequence, and the width of the thin film segments 3041 gradually increases; the rear end of the thick film segment 3040 is larger than the thickness of the thin film segment 3041, and the anti-deformation strength of the thick film segment 3040 is greater than that of the thin film segment 3041.

[0056] In step 3), during the process of the blower injecting gas with a set pressure into the deformation space 305 through the pipeline 307, the range of the convex deformation of the thin film segment 3041 towards the glue-containing space is greater than the range of the convex deformation of the thick film segment 3040 towards the glue-containing space, and the deformation speed of the thin film segment 3041 is greater than the deformation speed of the thick film segment 3040.

[0057] During the spraying process of the first fluorescent glue layer 103, the film layer 304 is deformed towards the glue-containing space under the drive of the gas with a set pressure. At the same time, since the film layer 304 includes a plurality of thick film segments 3040 and a plurality of thin film segments 3041, and the anti-deformation capabilities and deformation speeds of the thick film segments 3040 and the thin film segments 3041 are different, in this way, under the drive of the gas with a set pressure, the thick film segments 3040 and the thin film segments 3041 of the film layer 304 continuously deform in a concave-convex shape, showing a continuous state, promoting the ejection of the first fluorescent glue layer 103 from the glue spraying port 303, and making the first fluorescent glue layer 103 sprayed out from the glue spraying port 303 be sprayed continuously.

[0058] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A light source powder spraying method for improving product yield, characterized in that It includes the following steps: 1). Provide a substrate which has a light-emitting area. Fix chips on the light-emitting area to form a plurality of warm white light-emitting chips and positive white light-emitting chips arranged at intervals. The warm white light-emitting chips and the positive white light-emitting chips are respectively in a square shape. 2). Perform wire bonding to electrically connect the plurality of warm white light-emitting chips and the plurality of positive white light-emitting chips to the pads in the substrate through wires. 3). Provide a template which has a plurality of hollow grooves that penetrate the template vertically. The outer periphery of the hollow groove protrudes outward to form four outer convex grooves, and the plurality of outer convex grooves penetrate the template vertically. Place the template on the substrate. The hollow groove is arranged vertically aligned with the warm white light-emitting chip. The outer periphery of the hollow groove is arranged deviated from the outer periphery of the warm white light-emitting chip, and the plurality of outer convex grooves are respectively aligned with the four corner positions of the warm white light-emitting chip. Spray a first fluorescent glue layer through the hollow groove and the outer convex groove of the template. The first fluorescent glue layer covers the warm white light-emitting chip. 4). Set a dam on the substrate. The dam surrounds the outer periphery of the light-emitting area, and the light-emitting area encloses a surrounding area. 5). Spray a second fluorescent glue layer in the surrounding area. The second fluorescent glue layer covers the warm white light-emitting chip, the first fluorescent glue layer and the positive white light-emitting chip.

2. The light source powder spraying method for improving product yield as described in claim 1, characterized in that, In step 5), when the second fluorescent glue layer is cured, a light source is formed. Place the light source in a spectrometer for spectral screening.

3. The light source powder spraying method for improving the product yield as described in claim 2, characterized in that, In step 5), when the light source passes through the spectral screening of the spectrometer, it is packed and stored in the warehouse.

4. The light source powder spraying method for improving the product yield rate as described in claim 1, wherein, In step 3), after spraying the first fluorescent glue layer on the warm white light-emitting chip, place the substrate in a baking machine for baking until the first fluorescent glue layer is cured.

5. The light source powder spraying method for improving product yield according to claim 4, wherein In step 5), after spraying the second fluorescent glue layer in the surrounding area, place the substrate in a baking machine for baking until the second fluorescent glue layer is cured.

6. The light source powder spraying method for improving the product yield according to any one of claims 1 to 5, characterized in that, The outer periphery of the hollow groove has an arc section located between adjacent outer convex grooves, and the arc section protrudes and bends outward deviating from the hollow groove.

7. The light source powder spraying method for improving product yield as described in claim 6, characterized in that, Along the direction from the inside to the outside of the outer convex groove, the width of the outer convex groove gradually decreases.

8. The light source powder spraying method for improving product yield according to claim 7, characterized in that, The inner end of the outer convex groove communicates with the hollow groove, and the outer end of the outer convex groove is in a tip shape.

9. The light source powder spraying method for improving the product yield according to any one of claims 1 to 5, characterized in that In step 3), spray the first fluorescent glue layer on the template through a spray head. The spray head is connected to a glue delivery pipe. The spray head is provided with a horizontally arranged extrusion cavity. A plurality of glue inlet holes for the first fluorescent glue layer to pass through are formed at the rear end of the extrusion cavity, and the plurality of glue inlet holes are arranged at intervals along the horizontal direction of the extrusion cavity. A flat glue spraying port is formed at the front end of the extrusion cavity, and the glue spraying port extends along the horizontal direction of the extrusion cavity. Along the direction from the rear to the front of the extrusion cavity, the extrusion cavity is large in the middle and small at both ends; two elastic film layers are provided in the extrusion cavity, the two film layers are arranged opposite to each other and are respectively located on both sides of the glue spraying port, and a glue containing space is enclosed between the two film layers; both ends of the film layer are fixedly connected to the inner side wall of the extrusion cavity, and there is a deformation space between the middle part of the film layer and the inner side wall of the extrusion cavity; air inlets are respectively arranged on both sides of the spraying head, the air inlets are communicated with the deformation space, and the air inlets are connected to a fan through pipelines; In step 3), during the process of conveying the first fluorescent glue layer to the glue containing space through the glue conveying pipe, the fan injects gas with a set pressure into the deformation space through the pipeline, driving the film layer to deform towards the glue containing space, and simultaneously squeezing the first fluorescent glue layer in the glue containing space to be continuously extruded from the glue spraying port, and spraying the first fluorescent glue layer extruded through the glue spraying port onto the template. The first fluorescent glue layer passes through the hollow grooves and the convex grooves to form a first fluorescent glue layer covering the warm white chip.

10. The light source powder spraying method for improving the product yield as described in claim 9, characterized in that, The film layer includes a plurality of thick film segments and a plurality of thin film segments. Along the direction from the rear end to the front end of the extrusion cavity, the thick film segments and the thin film segments are staggeredly butted in sequence, and the width of the thin film segments gradually increases; the rear end of the thick film segment is larger than the thickness of the thin film segment, and the anti-deformation strength of the thick film segment is greater than that of the thin film segment; In step 3), during the process of the fan injecting gas with a set pressure into the deformation space through the pipeline, the range of the convex deformation of the thin film segment towards the glue containing space is greater than that of the thick film segment towards the glue containing space, and the deformation speed of the thin film segment is greater than that of the thick film segment.

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