A substrate-free CSP packaging method and light source for a multi-color light source

Abstract

The present invention provides a substrate-free CSP packaging method for a multi-color light source. Multiple blue light flip chips are successively fixed onto phosphor films of various colors, and transparent silicone is dotted. After dotting the transparent silicone, die bonding is performed. After die bonding is completed, it is placed in an oven for baking to cure the glue. After baking, plasma cleaning is carried out. White wall glue is injected between adjacent blue light flip chips, and after dotting the white wall glue, it is placed in an oven for baking to completely cure it. An optical spectrometer is used to test the optoelectronic parameters of the multi-color light source. The multi-color light source is cut into unit multi-color light sources by means of water jet cutting. The cut unit multi-color light sources are placed in an oven for baking and dehumidifying. The finished products of the unit multi-color light sources are sorted and packaged by a sorter using the MAP diagram of the spectral data. Compared with the existing substrate-based packaging CSP soldering process, the packaging process of the multi-color CSP is optimized, the yield is improved, and the packaging cost is saved. In addition, the light density is increased by more than 50%, and the light output effect is better.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging, and particularly to a substrate-free CSP packaging method, a preparation jig and a light source for a multi-color light source. Background Art

[0002] With the development of LED technology, people's demand for lighting is no longer limited to white light, and they pursue more of human centric lighting. Human centric lighting technology refers to the application of lighting technology to perfectly integrate lighting, climate and space, so as to help people in terms of body, emotion, health, etc., and meet the humanized lighting needs of personnel in a specific application environment.

[0003] Therefore, atmosphere lights, stage lights, wall washing lights, etc. have developed rapidly. Currently, four-color light sources on the market are generally based on RGBW or RGBA lamp beads, such as low and medium power PPA, PCT packages 2835, 3030, 5050, etc., and medium and high power EMC, SMC and ceramic packages 3535, 5050, etc. As a new trend in LED packaging in recent years, compared with lamp beads, CSP does not require brackets, die bonding glue and other materials, and has the characteristics of low cost. It is widely used in low-power lighting strips. Moreover, flip-chip CSP does not require gold wires, the product reliability is higher, and the power can reach more than 1W. Especially in the application of landscape lighting and atmosphere lights, CSP has obvious advantages in terms of cost performance compared with lamp beads.

[0004] Currently, most of the CSP packaging methods on the market are with substrate packaging. For example, Hongli Zhihui Group Co., Ltd. has applied for a patent "A Multi-color CSP-packaged LED", application number: 2020211897308. Its disadvantages are high cost, low yield and poor light output effect. Summary of the Invention

[0005] The main object of the present invention is to provide a substrate-free CSP packaging method, a preparation jig and a light source for a multi-color light source, aiming to improve the technical problems of high packaging cost, low yield and poor light output effect in the prior art.

[0006] To achieve the above object, the present invention provides a substrate-free CSP packaging method for a multi-color light source, including the following steps:

[0007] Sequentially fix a plurality of blue light flip chips on phosphor sheets of various colors, and dot transparent silica gel. After dotting the transparent silica gel, die bonding is performed;

[0008] After die bonding is completed, put it into an oven for baking to cure the glue;

[0009] Perform plasma cleaning after baking;

[0010] Inject white wall glue between adjacent blue light flip chips, and bake them in an oven after the white wall glue is applied to make it fully cured;

[0011] Use a spectro-testing machine to test the optoelectronic parameters of the multi-color light source;

[0012] Cut the multi-color light source into unit multi-color light sources by means of water jet cutting;

[0013] Put the cut unit multi-color light sources into an oven for baking and dehumidifying;

[0014] Sort and package the finished products of the unit multi-color light sources by means of a sorter using the MAP diagram of the spectro data.

[0015] Optionally, before the step of sequentially fixing multiple blue light flip chips onto phosphor films of various colors, applying transparent silica gel, and performing die bonding after the transparent silica gel is applied, it further includes:

[0016] Fabricate red phosphor films, green phosphor films, transparent films, and yellow phosphor films;

[0017] Arrange the phosphor films of various colors in sequence, and bond the phosphor films of various colors through the UV films exposed by the window areas of the release films;

[0018] After the phosphor films of various colors are fixed, put them into a laminating machine and use a flat mold for lamination;

[0019] Inject transparent silica gel into the mold, keep the pressure and bake at a temperature of 120°C - 130°C for 5 min - 10 min, and demold after baking. After demolding, put it into an oven for baking again;

[0020] Place the glass substrate on a UV machine to remove the glue, reduce the viscosity of the double-sided UV film, and then laminate the entire film onto the crystal placement board.

[0021] Optionally, the step of fabricating red phosphor films, green phosphor films, transparent films, and yellow phosphor films includes:

[0022] Mix red powder, green powder, yellow powder with transparent silica gel and anti-settling powder fumed silica in a certain proportion by vacuum stirring and defoaming to prepare phosphor glue;

[0023] Make phosphor glue films of various colors from the phosphor glue by means of blade coating;

[0024] Place the phosphor glue films on a dust-proof heating platform, vacuum adsorb and bake at 100°C to form the phosphor films;

[0025] Place the cured phosphor films of various colors on a film testing machine for optical testing;

[0026] Cut each phosphor film sheet with qualified optical parameters into unit film sheets by laser cutting;

[0027] Transfer the cut film sheets of each color to the dicing ring by the method of pouring film.

[0028] Optionally, the steps of mixing red phosphor, green phosphor, yellow phosphor with transparent silica gel and anti-settling powder fumed silica in a certain proportion by vacuum stirring and defoaming to prepare phosphor glue include:

[0029] Put the monochromatic phosphor, transparent silica gel and anti-settling powder fumed silica into a glass and stir evenly according to the mass ratio of 2:1:0.01;

[0030] Put the prepared phosphor glue into a centrifugal stirrer and stir, and the stirring conditions are 2000rpm / 1min;

[0031] Put the stirred material into a vacuum defoaming machine for defoaming, the vacuum degree is -0.1MPa, and the defoaming time is 10-20 minutes.

[0032] Optionally, the steps of placing the cured phosphor film sheets of each color on a film tester for testing include:

[0033] Place the blue flip-chip LED chip under the phosphor film sheet to be tested, and place the integrating sphere above the phosphor film sheet to be tested;

[0034] The blue flip-chip LED chip emits blue light to excite the phosphor film sheets of different colors to emit different colors of light. The film sheet to be tested moves in an S shape on the dicing ring to realize the measurement of the optical parameters of the entire film sheet. After the test, analyze whether the luminous flux, XY coordinates, and dominant wavelength meet the product requirements.

[0035] In addition, to achieve the above object, the present invention also proposes a jig for preparing a multi-color light source film sheet, including a glass substrate, a double-sided UV film, and a transparent release film. The double-sided UV film is bonded to the glass substrate, and the transparent release film is bonded to the double-sided UV film.

[0036] Optionally, a plurality of patterns with the same size as the chip are printed on the surface of the glass substrate.

[0037] Optionally, alignment parts are provided at the edges of the glass substrate, and a plurality of window holes and alignment holes are provided on the transparent release film. The positions of the window holes correspond to the positions of die bonding on the glass substrate one by one.

[0038] In addition, to achieve the above object, the present invention further provides a multi-color light source, including a plurality of blue light flip-chip chips, phosphor films of different colors, a plurality of positive pads, and a plurality of negative pads. Each of the phosphor films of different colors is provided on the surface of each blue light flip-chip chip, and one of the positive pads and one of the negative pads are respectively provided at the bottom of each blue light flip-chip chip.

[0039] Optionally, the number of the blue light flip-chip chips is four, and the four blue light flip-chip chips are arranged in a square shape.

[0040] The present invention provides a substrate-free CSP packaging method for a multi-color light source, including: sequentially fixing a plurality of blue light flip-chip chips onto phosphor film sheets of various colors, dotting transparent silica gel, and performing die bonding after dotting the transparent silica gel; putting it into an oven for baking after die bonding to cure the glue; performing plasma cleaning after baking; injecting white wall glue between adjacent blue light flip-chip chips, and putting it into an oven for baking to completely cure it after dotting the white wall glue; testing the optoelectronic parameters of the multi-color light source by using a spectral test machine; cutting the multi-color light source into unit multi-color light sources by using a water jet cutting method; putting the cut unit multi-color light sources into an oven for baking and dehumidifying; sorting and packaging the finished products of the unit multi-color light sources by using a sorter according to the MAP diagram of spectral data. Compared with the existing substrate-based packaging CSP soldering process, the packaging process of the multi-color CSP is optimized, the yield is improved, and the packaging cost is saved; in addition, the light density is increased by more than 50%, and the light output effect is better. Description of the Drawings

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0042] Figure 1 It is a schematic flow chart of an embodiment of the substrate-free CSP packaging method for the multi-color light source provided by the present invention;

[0043] Figure 2 It is a schematic flow chart of an embodiment of the substrate-free CSP packaging method for the multi-color light source provided by the present invention;

[0044] Figure 3 It is a schematic flow chart of an embodiment of the substrate-free CSP packaging method for the multi-color light source provided by the present invention;

[0045] Figure 4 It is a schematic structural diagram of the multi-color light source provided by the present invention;

[0046] Figure 5 is Figure 4 a schematic structural view of the back side of a multi-color light source in

[0047] Figure 6 is Figure 4 a side view of the multi-color light source in

[0048] Figure 7 a schematic structural view of a jig for preparing a multi-color light source film provided by the present invention;

[0049] Figure 8 is Figure 7 a schematic structural view of a glass substrate in

[0050] Figure 9 is Figure 8 a partial enlarged view of part A in

[0051] Figure 10 is Figure 7 a schematic structural view of a transparent release film in

[0052] Figure 11 is Figure 4 a schematic structural view of a phosphor film in

[0053] Explanation of reference numerals in the drawings:

[0054] Label Name Label Name 100 Multi-color light source 163 Red light positive electrode 15 Flip chip 164 Red light negative electrode 11 Fluorescent glue film 165 White light positive electrode 111 Red fluorescent powder glue film 166 White light negative electrode 112 Green fluorescent powder glue film 167 Blue light positive electrode 113 Transparent glue 168 Blue light negative electrode 114 Yellow fluorescent powder glue film 41 Glass substrate 12 Transparent silica gel 42 Double-sided UV film 13 White wall glue 43 Transparent release film 16 Pad 21 Alignment part 161 Green light positive electrode 31 Alignment hole 162 Green light negative electrode 53 Transparent film 51 Red fluorescent powder film 54 Yellow fluorescent powder film 52 Green fluorescent powder film

[0055] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0056] In order to make the object, technical solution and advantages of the present invention more clear and understandable, the present invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. The technical solutions in the present invention are clearly and completely described. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

[0057] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In the following detailed description, for the sake of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, obviously, one or more embodiments can also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0058] The terms used herein are for describing specific embodiments only and are not intended to limit the present invention. The terms "comprising", "including" and the like as used herein indicate the presence of the described features, steps, operations and / or components, but do not preclude the presence or addition of one or more other features, steps, operations or components.

[0059] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those of ordinary skill in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted to have a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0060] In the case of using expressions such as "at least one of A, B, and C, etc.", generally it should be interpreted according to the meaning commonly understood by those of ordinary skill in the art (for example, "a system having at least one of A, B, and C" should include but not be limited to a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", generally it should be interpreted according to the meaning commonly understood by those of ordinary skill in the art (for example, "a system having at least one of A, B, or C" should include but not be limited to a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0061] It should be noted that if there are directional indications involved in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0062] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution where A and B are satisfied simultaneously. Also, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0063] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It 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, and therefore should not be construed as a limitation to the present invention.

[0064] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0065] In addition, in the description of the present invention, unless otherwise stated, the meanings of "multiple", "multiple roots", and "multiple groups" are two or more.

[0066] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0067] At present, there are two packaging methods for CSP on the market. One is the packaging with a substrate. The CSP finished product is obtained by processes such as die bonding, wire bonding, encapsulation, and cutting on a ceramic substrate or other substrates, which is the same as the packaging method of the lamp beads. The other is the packaging without a substrate, where the fluorescent glue is encapsulated on the surface of the flip chip and white glue is surrounded around. Both of the above two packaging methods can be used for monochromatic CSP, and the packaging with a substrate is mostly used for multicolor CSP. To optimize the existing solutions, the present invention adopts a process of integrally forming a multi-color phosphor film, and realizes a CSP with multi-color independent control and without a substrate through a scheme of exciting different color phosphor films by multiple flip-chip blue light chips. Refer to Figure 1 , Figure 1 which is a schematic flow chart of an embodiment of the method for packaging a multi-color CSP without a substrate according to the present invention. In one embodiment, the method for packaging a multi-color light source CSP without a substrate includes the following steps:

[0068] Step S10: Fix a plurality of blue light flip chips 15 onto the phosphor films of various colors in sequence, and dot the transparent silica gel 12. After dotting the transparent silica gel 12, perform die bonding.

[0069] Step S20: After die bonding is completed, place it in an oven for baking to cure the glue.

[0070] Step S30: Perform plasma cleaning after baking.

[0071] Step S40: Inject white wall glue 13 between adjacent blue light flip chips 15, and after the white wall glue 13 is applied, place it in an oven for baking to make it fully cured.

[0072] Step S50: Use a spectrophotometer tester to test the optoelectronic parameters of the multicolor light source 100.

[0073] Step S60: Cut the multicolor light source 100 into unit multicolor light sources by means of water jet cutting.

[0074] Step S70: Place the cut unit multicolor light sources in an oven for baking and dehumidification.

[0075] Step S80: Sort and package the finished products of the unit multicolor light sources through the MAP diagram of spectroscopic data using a sorter.

[0076] In this embodiment, by using a die bonder to sequentially bond the blue light flip chips 15 to phosphor films of different colors, then apply transparent silicone 12, and immediately perform die bonding after applying the transparent silicone 12 so that the chip surface is bonded to the fluorescent glue film 11. The fluorescent glue films 11 are respectively a red phosphor glue film 111, a green phosphor glue film 112, a transparent glue 113, and a yellow phosphor glue film 114.

[0077] After die bonding is completed, place it in an oven. The temperature of the oven is set to 150 °C, and bake for 30 minutes to cure the glue. Perform plasma cleaning on the baked material to increase the adhesion between the white wall glue 13 and the chip. Use a dispensing machine to inject white wall glue 13 between the chips. The height of the white wall glue 13 is flush with or slightly lower than the chip pads 16 of the chip, but does not exceed 0.05 mm. After applying the white wall glue 13, place it in an oven for baking. The temperature of the oven is set to 150 °C, and bake for four hours to cure the white wall glue 13. Then, use a spectrophotometer tester to test the optoelectronic parameters of the multicolor light source 100. After the optoelectronic parameters are tested, cut the multicolor light source into unit multicolor light sources by means of water jet cutting, and place the cut unit multicolor light sources in an oven for baking. The temperature of the oven is set to 80 °C, and bake for two hours for dehumidification.

[0078] Finally, the finished products of the multi-color light sources of the unit are sorted and packaged by a sorter using the MAP diagram of the spectroscopic data. Specifically, it includes: transferring the dehumidified materials to the dicing ring and placing them at the material taking position of the sorter; retrieving the spectroscopic data on the spectroscope, converting the BIN area of a single CSP in the spectroscopic data into a lamp bead MAP diagram, and confirming that the MAP diagram of the CSP is consistent with the physical object; the sorter transfers the CSPs in the same BIN area to the blue film for packaging by means of crystal picking and die bonding according to the lamp bead MAP diagram.

[0079] See Figure 2 and Figure 11 , before chip fabrication, it is also necessary to prepare the phosphor films of each color. Therefore, before step S10, the following steps are also included:

[0080] Step S01: Fabricate a red phosphor film 51, a green phosphor film 52, a transparent film 53, and a yellow phosphor film 54.

[0081] Step S02: Arrange the phosphor films of each color in sequence, and bond the phosphor films of each color through the UV film exposed by the die-cutting area of the release film.

[0082] Step S03: After the phosphor films of each color are fixed, place them in a laminating machine and use a flat mold for lamination.

[0083] Step S04: Inject transparent silicone 12 into the mold, keep the pressure and bake at a temperature of 120°C - 130°C for 5 min - 10 min, and demold after baking. After demolding, place it in the oven for baking again.

[0084] Step S5: Place the glass substrate 41 on the UV machine to remove the glue, reduce the viscosity of the double-sided UV film 42, and then bond the entire film to the crystal plate.

[0085] In this embodiment, film fixing: Arrange the red phosphor film 51, the green phosphor film 52, the transparent film 53, and the yellow phosphor film 54 in sequence through a die bonder, and bond the phosphor films through the UV film exposed by the die-cutting area of the release film; film laminating: After the film is fixed, place it in a laminating machine and use a flat mold for lamination. The depth of the mold is 1.5 mm; inject transparent silicone 12 into the mold, keep the pressure and bake for 5 - 10 min, the baking temperature is 125 ± 5°C, demold after baking, and then place it in the oven for baking again to achieve the integrated molding of the multi-color film. The baking conditions are 150°C / 1H; film inversion: Place the glass substrate 41 on the UV machine to remove the glue, reduce the viscosity of the double-sided UV film 42, and then bond the entire film to the crystal plate. The specific implementation method is that the fluorescent glue film 11 should be placed upward and the transparent silicone 12 should be placed downward.

[0086] The colored light is a specific color different from white light, such as yellow, green, red, etc. The phosphor films of specific colors are yellow phosphor film 54, green phosphor film 52, red phosphor film 51, infrared phosphor film, etc. In actual applications, phosphor films of any color can be prepared according to requirements. See Figure 3 , and the specific method steps are as follows: Among them, step S1 includes:

[0087] Step S101: Mix and defoam red powder, green powder, yellow powder with transparent silica gel 12 and anti-settling powder fumed silica in a certain proportion under vacuum stirring to prepare a phosphor glue.

[0088] Step S102: Make the phosphor glue into various colored phosphor glue films 11 by the film scraping method.

[0089] Step S103: Place the phosphor glue film 11 on a dust-proof heating platform, and bake it at 100 °C under vacuum adsorption to form the phosphor film.

[0090] Step S104: Place the solidified phosphor films of various colors on a film tester for optical testing.

[0091] Step S105: Cut the phosphor films of various colors with qualified light parameters into unit films by laser cutting;

[0092] Step S106: Transfer the cut films of each color to the dicing frame by the film inversion method.

[0093] In this embodiment, red powder, green powder, yellow powder are mixed and defoamed with transparent silica gel 12 and anti-settling powder fumed silica in a certain proportion under vacuum stirring to prepare a phosphor glue. The mass ratio of the monochromatic phosphor to the transparent silica gel 12 is 2:1; the particle size of the monochromatic phosphor is 5 - 20 μm; the mass ratio of the anti-settling powder fumed silica to the transparent silica gel 12 is 0.01:1; the particle size of the anti-settling powder fumed silica is 5 - 10 nm.

[0094] Film making: Make the phosphor glue into a phosphor glue film 11 by the film scraping method, and the thickness of the phosphor glue film 11 is about 30 - 80 μm; Film baking: Place the phosphor glue film 11 on a dust-proof heating platform, bake it at 100 °C under vacuum adsorption, and the baking time is 15 - 30 min to make it solidify.

[0095] Film cutting: Cut the film with qualified light parameters into unit films by laser cutting, and the film size is 0.05 mm larger than the length and width of the chip size to ensure that the film can completely cover the chip;

[0096] Film inversion: Transfer the cut films of each color to the dicing frame by the film inversion method for the operation of the die bonder.

[0097] Furthermore, in this embodiment, step S101 includes the following steps:

[0098] Step S1011: Put the monochrome fluorescent powder, transparent silica gel 12 and anti-precipitation powder fumed silica into a glass cup at a mass ratio of 2:1:0.01 and stir evenly.

[0099] Step S1012: Put the prepared phosphor glue into a centrifugal mixer and stir it at a stirring condition of 2000 rpm / 1 min.

[0100] Step S1013: Place the stirred material into a vacuum degassing machine for degassing, with a vacuum degree of -0.1 MPa and a degassing time of 10 to 20 minutes.

[0101] Further, in this embodiment, step S104 includes the following steps:

[0102] Step S1041: placing the blue flip-chip LED chip 15 below the phosphor film to be tested, and placing an integrating sphere above the phosphor film to be tested.

[0103] Step S1042: The blue flip-chip LED chip 15 emits blue light to excite the phosphor films of different colors to emit light of different colors. The film to be tested is placed on the crystal expansion ring and moves in an S shape to measure the optical parameters of the entire film. After the test, analyze whether the luminous flux, XY coordinates, and main wavelength meet the product requirements.

[0104] It can be understood that the optical test is to place the cured fluorescent adhesive film 11 on a film testing machine for testing, wherein the blue flip-chip LED chip 15 is placed under the film to be tested, and the integrating sphere is placed above the film to be tested. The blue flip-chip LED chip 15 emits blue light to excite phosphor films of different colors to emit light of different colors. The film to be tested is placed on the crystal expansion ring and moves in an S shape to achieve the measurement of the optical parameters of the entire film. After the test, the luminous flux, XY coordinates, and main wavelength are analyzed to see whether they meet the product requirements.

[0105] In addition, in order to achieve the above-mentioned invention object, see Figures 7 - 10 The present invention also provides a jig for preparing a multi-color light source film, including a glass substrate 41, a double-sided UV film 42 and a transparent release film 43, wherein the double-sided UV film 42 is bonded to the glass substrate 41, and the transparent release film is bonded to the double-sided UV film 42.

[0106] The fixture is composed of a flat glass substrate 41, a high-transparency double-sided UV film 42 and a transparent release film 43. Figure 10As shown in the figure, several patterns with the same size as the chip are printed on the surface of the planar glass substrate 41 by laser. A registration part 21 for registration marking is provided at the edge of the substrate. The thickness of the glass substrate 41 is 1.2 mm. A high-transparency double-sided UV film 42 is adhered to the surface of the glass substrate 41, and the thickness of the double-sided UV film 42 is 0.1 mm. A transparent release film 43 is adhered to the surface of the double-sided UV film 42. The transparent release film 43 is provided with several window openings and registration holes 31. As Figure 11 shown, the positions of the window openings correspond one by one to the die bonding positions on the glass substrate, and the window opening size is 80% of the chip size. The thickness of the transparent release film 43 is 0.1 mm.

[0107] In addition, to achieve the above invention object, referring to Figure 1 , the present invention also provides a multi-color light source 100, which includes a plurality of blue light flip-chip 15, fluorescent glue films 11 of different colors, a plurality of positive electrode pads, and a plurality of negative electrode pads. Each of the blue light flip-chip 15 is provided with the fluorescent glue films 11 of different colors on its surface, and each of the blue light flip-chip 15 is respectively provided with a positive electrode pad and a negative electrode pad at its bottom.

[0108] Specifically, referring to Figure 4 、 Figure 5 、 Figure 6 , in this embodiment, the number of chips is four, and all the chips are blue light flip-chip 15, arranged in a square pattern. The bottom electrodes of the chips are pads 16. Different colors of fluorescent glue films 11 are distributed on the surfaces of the four chips. The fluorescent glue films 11 are adhered to the surfaces of the blue light flip-chip 15 by transparent silica gel 14. The fluorescent glue films 11 are respectively a red fluorescent powder glue film 111, a green fluorescent powder glue film 112, a transparent glue 113, and a yellow fluorescent powder glue film 114. A layer of transparent silica gel 12 is laminated on the surface of the fluorescent glue film. The white wall glue 13 fills the gaps between the chips. There are eight pads at the bottom of the CSP, namely a green light positive electrode 161, a green light negative electrode 162, a red light positive electrode 163, a red light negative electrode 164, a white light positive electrode 165, a white light negative electrode 166, a blue light positive electrode 16.7, and a blue light negative electrode 168. Similar to the four-color LED lamp beads, independent control of each color is achieved, and the positive and negative electrode sequences of each color can be randomly combined according to the PCB board design.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. The specific embodiments described above have further elaborated on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above is only the specific embodiments of the present invention and is not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A substrate-free CSP packaging method for a multi-color light source, characterized in that, The steps include: Arrange the phosphor film sheets of different colors in sequence, adhere the phosphor film sheets of different colors to the UV film exposed in the window area of the release film, and arrange the phosphor film sheets in correspondence with the pattern arranged on the glass substrate on the side of the UV film away from the release film, wherein the pattern is formed by laser printing; Using a flat mold to press the phosphor films of different colors; Injecting transparent silicone into the mold, and baking under pressure, demoulding, and baking to form an integrated multi-color membrane, wherein the multi-color membrane includes a transparent silicone layer and fluorescent powder membranes of various colors arranged on the transparent silicone layer; Reducing the viscosity of the UV film to adhere the integrated multi-color film to the wafer; Sequentially fixing a plurality of blue light flip chips onto phosphor films of different colors, and applying transparent silica gel, and then performing die bonding after applying the transparent silica gel; After the die bonding is completed, put it in the oven to bake to solidify the glue; Plasma cleaning is performed after baking; Injecting white wall glue between adjacent blue light flip chips, and placing the white wall glue in an oven to bake it to fully solidify; Using a spectrophotometer to test the photoelectric parameters of the multicolor light source; Cutting the multi-color light source into units of multi-color light sources by water jet cutting; Putting the cut multi-color light source of the unit into an oven for baking and dehumidification; The finished products of the multi-color light source of the unit are sorted and packaged by a sorting machine according to a MAP diagram of the spectral data.

2. The substrate-free CSP packaging method for a multi-color light source according to claim 1, wherein The method further includes the following steps before the plurality of blue light flip chips are sequentially fixed to the phosphor films of different colors and transparent silicone is applied, and before the step of performing the crystal bonding after the transparent silicone is applied: Making red phosphor film, green phosphor film, transparent film and yellow phosphor film; Arranging the phosphor film sheets of different colors in sequence, and bonding the phosphor film sheets of different colors through the UV film exposed in the window area of the release film; After the phosphor films of different colors are solidified, they are placed in a laminating machine and pressed using a flat mold; Inject transparent silicone into the mold, bake at 120℃-130℃ for 5min-10min, demould after baking, and bake in the oven again after demoulding; Place the glass substrate on a UV machine to debond and reduce the viscosity of the double-sided UV film before attaching the entire film to the crystal plate.

3. The substrate-free CSP packaging method for a multi-color light source according to claim 2, characterized in that, The steps of making a red phosphor film, a green phosphor film, a transparent film and a yellow phosphor film include: Red powder, green powder, yellow powder, transparent silica gel, and anti-precipitation powder fumed silica are respectively mixed and degassed in a certain proportion under vacuum to prepare fluorescent powder glue; The fluorescent powder glue is made into fluorescent glue films of various colors by scraping film; Placing the fluorescent adhesive film on a dustproof heating platform and baking it at 100° C. under vacuum adsorption to form the fluorescent powder film; Placing the solidified phosphor films of various colors on a film testing machine for optical testing; Cutting the phosphor films of various colors that meet the light parameter standards into unit films by laser; The cut film of each color is transferred to the expansion machine by inverting the film.

4. The substrate-free CSP packaging method for a multi-color light source according to claim 3, characterized in that, The steps of mixing red powder, green powder, yellow powder, transparent silica gel, and anti-precipitation powder fumed silica in a certain proportion and degassing in vacuum to prepare fluorescent powder glue include: Put the monochromatic phosphor, transparent silica gel and anti-settling fumed silica in a glass cup in a mass ratio of 2:1:0.01 and stir evenly; Put the prepared phosphor glue into a centrifugal mixer and stir under the conditions of 2000 rpm / 1 min; Put the stirred material into a vacuum degassing machine for degassing, with a vacuum degree of -0.1 MPa and a degassing time of 10 - 20 minutes.

5. The substrate-free CSP packaging method for a multi-color light source according to claim 3, characterized in that, The steps of placing the cured phosphor film sheets of various colors on a film tester for testing include: Place the blue light flip-chip below the phosphor film sheet to be tested, and place the integrating sphere above the phosphor film sheet to be tested; The blue light emitted by the blue light flip-chip excites the phosphor film sheets of different colors to emit different colors of light. The film sheet to be tested moves in an S shape on the expansion ring, realizing the measurement of the optical parameters of the entire film sheet. After the test, analyze whether the luminous flux, XY coordinates, and dominant wavelength meet the product requirements.

6. A multi-color light source, characterized in that, The multi-color light source is prepared by the substrate-free CSP packaging method of the multi-color light source according to any one of claims 1 to 5. The multi-color light source includes a plurality of blue light flip-chips, phosphor glue films of different colors, a plurality of positive electrode pads, and a plurality of negative electrode pads. Different colors of the phosphor glue films are provided on the surface of each blue light flip-chip, and a positive electrode pad and a negative electrode pad are respectively provided at the bottom of each blue light flip-chip.

7. The multi-color light source according to claim 6, wherein The number of the blue light flip-chips is four, and the four blue light flip-chips are arranged in a cross shape.

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