LED packaging device and preparation method and application thereof

Abstract

The invention provides an LED packaging device and a preparation method and application thereof, and relates to the technical field of semiconductor devices.The preparation method comprises the steps that packaging silica gel and fluorescent powder are mixed according to a preset proportion, and then a film with the preset thickness is prepared through a film scraping machine; curing the membrane at a first preset temperature for a first preset time, and completing primary curing to obtain a semi-cured fluorescent sheet; transferring the semi-cured fluorescent sheet to the flip LED chip which is subjected to die bonding in the bracket, and carrying out vacuum pressure sinking, so that the semi-cured fluorescent sheet is completely attached to the surface and the side surface of the flip LED chip; curing the semi-cured fluorescent sheet subjected to vacuum pressure sinking at a second preset temperature for a second preset time, and completing secondary curing to obtain a cured finished product; according to the LED packaging device and the manufacturing method thereof, the technical problems that in the prior art, the stability of the dispensing glue amount of the LED packaging device is poor, fluorescent powder is not evenly distributed, and consequently the brightness and the concentration degree are reduced can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor devices, and in particular to an LED packaging device and a preparation method and application thereof. Background Art

[0002] LED packaging devices are widely used in lighting, display, backlight and other fields due to their unique optoelectronic properties and ultra-long lifespan. As the next-generation lighting method with clear advantages, they have attracted widespread attention.

[0003] Typically, LED packages consist of a bracket, LED chip, glue, and phosphor. The manufacturing process typically involves die bonding, bonding, dispensing, and measurement. However, during the dispensing process, insufficient glue volume consistency or uneven phosphor distribution within the adhesive can lead to high dispersion and poor concentration, resulting in reduced brightness and concentration in the LED package. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide an LED packaging device and its preparation method and application, aiming to solve the technical problems in the existing technology of LED packaging devices such as poor glue dispensing stability and uneven distribution of phosphor, which lead to decreased brightness and concentration.

[0005] A first aspect of the present invention is to provide a method for preparing an LED package device, the method comprising: The encapsulated silica gel and phosphor are mixed in a preset ratio, and then a film with a preset thickness is prepared by a scraping machine; curing the film at a first preset temperature for a first preset time to complete a primary curing to obtain a semi-cured fluorescent sheet; Transferring the semi-cured phosphor sheet to the flip-chip LED chip that has been crystal-bonded in the bracket, and vacuum pressing it so that the semi-cured phosphor sheet is completely attached to the surface and side of the flip-chip LED chip; Curing the vacuum pressed semi-cured fluorescent sheet at a second preset temperature for a second preset time to complete secondary curing to obtain a cured product; The cured product is encapsulated with transparent adhesive to obtain an LED package device.

[0006] Compared with the prior art, the beneficial effect of the present invention is that: through the preparation method of the LED packaging device provided by the present invention, the packaging silica gel and the phosphor are mixed to form a membrane, and a low-temperature short-time one-time curing is adopted to form a semi-cured phosphor sheet, and the membrane containing the phosphor is quickly converted from a liquid state to a semi-solid state to achieve one-time curing. Only a coupling reaction occurs in the one-time curing, and the basic structure is constructed in advance, so that the phosphor is initially fixed in the semi-cured phosphor sheet, reducing the risk of color point deviation in the later stage, avoiding the agglomeration and displacement of the phosphor in the subsequent transfer process or the chaos of the phosphor distribution and silica gel cross-linking, resulting in uneven distribution of the phosphor and unstable glue amount. Then, through high-temperature and long-time secondary curing, the packaging silica gel components are cross-linked, and the bonding force between the semi-cured phosphor sheet and the flip-chip LED chip and the bracket is enhanced to form a dense and stable structure, so that the excitation coupling between the phosphor and the flip-chip LED chip is more sufficient, and the brightness and concentration are improved, thereby solving the technical problems of poor stability of the dispensing glue amount and uneven distribution of phosphor in the LED packaging device in the prior art, which lead to a decrease in brightness and concentration.

[0007] According to one aspect of the above technical solution, the encapsulated silica gel includes vinyl silicone resin and polyurethane resin, the molecular weight of the polyurethane group in the polyurethane resin is 2000~10000, and the mass of the polyurethane resin is 30%~50% of the mass of the vinyl silicone resin.

[0008] According to one aspect of the above technical solution, in the film, the mass percentage of the phosphor is 20% to 80%.

[0009] According to one aspect of the above technical solution, the preset thickness is 80 μm to 120 μm.

[0010] According to one aspect of the above technical solution, the first preset temperature is 80° C. to 120° C., the first preset time is 2 min to 5 min, and the refractive index of the semi-cured fluorescent sheet is 1.50 to 1.52.

[0011] According to one aspect of the above technical solution, the semi-cured fluorescent sheet is in a square shape, and the side length of the semi-cured fluorescent sheet is the sum of twice the height of the flip-chip LED chip and the side length.

[0012] According to one aspect of the above technical solution, the second preset temperature is 150° C. to 170° C., and the second preset time is 120 min to 150 min.

[0013] According to one aspect of the above technical solution, the material of the transparent adhesive includes vinyl phenyl silicone resin, and the refractive index of the transparent adhesive is 1.47~1.49.

[0014] A second aspect of the present invention is to provide an LED package device, wherein the LED package device is manufactured by the above-mentioned method for manufacturing an LED package device.

[0015] The third aspect of the present invention is to provide an application of the above-mentioned LED packaging device in the fields of display, backlight and lighting. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which: Figure 1 This is a schematic diagram of a method for preparing an LED packaging device according to an embodiment of the present invention.

[0017] Component symbol description in the attached figure: Bracket 1, flip-chip LED chip 2, membrane 3, transparent adhesive 4, semi-cured fluorescent sheet 30. DETAILED DESCRIPTION

[0018] To make the objectives, features, and advantages of the present invention more readily apparent, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings. The accompanying drawings illustrate several embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive disclosure of the present invention. As used herein, the term "and / or" includes any and all combinations of one or more of the relevant listed items.

[0019] The technical solution of the present invention is described in detail below with reference to specific embodiments.

[0020] See also Figure 1 , shown is a method for preparing an LED packaging device provided by an embodiment of the present invention, the preparation method includes: steps S10 to S14.

[0021] Step S10, mixing the encapsulated silica gel and the phosphor according to a preset ratio, and then using a scraping machine to form a film of a preset thickness; The encapsulated silica gel comprises vinyl silicone resin and polyurethane resin, the molecular weight of the polyurethane group in the polyurethane resin is 2000-10000, and the mass of the polyurethane resin is 30%-50% of the mass of the vinyl silicone resin.

[0022] It should be noted that the introduction of polyurethane groups modifies the organic groups (phenyl, methyl, and other organic groups) on the silicone chain in the vinyl silicone resin to achieve a single-stage cure, which involves only a coupling reaction. By mixing the phosphor with the encapsulating silicone and semi-curing it to form a film, the phosphor's distribution uniformity can be effectively improved.

[0023] Furthermore, in the film 3, the mass percentage of the phosphor is 20% to 80%. Too much or too little phosphor will affect the position of the CIE color point, causing it to deviate from the target area, resulting in the white light color not meeting the standard.

[0024] Among them, CIE is the abbreviation of the International Commission on Illumination, which is an internationally authoritative organization for developing lighting and color standards. LED-related products must use CIE standards to evaluate color performance, that is, use the CIE chromaticity diagram to locate the color of white light and determine whether it meets the color temperature and color difference requirements of lighting and display scenes.

[0025] Furthermore, the preset thickness of the membrane 3 is 80 μm to 120 μm.

[0026] Step S11, curing the film at a first preset temperature for a first preset time to complete a primary curing to obtain a semi-cured phosphor sheet; Furthermore, the first preset temperature is 80° C. to 120° C., the first preset time is 2 min to 5 min, and the refractive index of the semi-cured fluorescent sheet 30 is 1.50 to 1.52.

[0027] It should be noted that, through a single low-temperature curing, only a coupling reaction occurs to form a semi-cured fluorescent sheet 30. The single curing mainly plays the role of forming the membrane 3, so that it can be evenly and stably transferred to the top of the chip. It can effectively solve the problem of unstable glue amount during the dispensing process. At the same time, the phosphor is initially fixed in the semi-cured fluorescent sheet 30, so that the phosphor is not easy to agglomerate or shift in the subsequent process, ensuring the spectral stability of the light after excitation, helping the CIE color point to approach the target area, improving the color consistency of white light, and solving the problem of uneven distribution of phosphor in the fluorescent glue.

[0028] In addition, through low-temperature one-time curing, the film 3 containing phosphor can be quickly converted from liquid to semi-solid, providing a stable form for subsequent processes such as bonding flip-chip LED chips 2, facilitating precise control of the thickness and size of the film 3, and ensuring the compatibility of the semi-cured phosphor sheet 30 with the flip-chip LED chip 2.

[0029] Preferably, the prepreg fluorescent sheet 30 is square in shape, with a side length equal to the sum of twice the height of the flip-chip LED chip 2 and its side length. The prepreg fluorescent sheet 30 is easy to process and can be rolled to a predetermined size to fit the side of the flip-chip LED chip 2, facilitating precise bonding and cross-linking during secondary curing.

[0030] It can be understood that the size of the semi-cured fluorescent sheet 30 is set according to the length, width and height dimensions of the flip-chip LED chip 2. If the size is too large, it will form piles and wrinkles; if the size is too small, it cannot completely cover the entire side, causing the side light source to leak out.

[0031] Step S12, transferring the semi-cured phosphor sheet to the flip-chip LED chip that has been die-bonded in the bracket, and vacuum pressing it so that the semi-cured phosphor sheet is completely attached to the surface and side surfaces of the flip-chip LED chip; Specifically, the vacuum deposition conditions are: -0.8atm~1atm, temperature 150℃~170℃, and time 180s~300s.

[0032] It can be understood that the semi-cured fluorescent sheet 30 has a certain plasticity. During vacuum depression, with the assistance of pressure and vacuum environment, the semi-cured fluorescent sheet 30 can fit tightly to the complex structure of the side of the flip-chip LED chip 2, fill the tiny gap, and create a uniform, bubble-free interface for the secondary curing complexation reaction, thereby ensuring the subsequent optical coupling effect, making the luminescence of the flip-chip LED chip 2 more fully coupled with the phosphor, with less light scattering, high excitation efficiency, more concentrated and brighter light output, directly optimizing the CIE color point stability and improving the quality of white light.

[0033] Step S13, curing the vacuum pressed semi-cured phosphor sheet at a second preset temperature for a second preset time to complete secondary curing to obtain a cured product; Furthermore, the second preset temperature is 150° C. to 170° C., and the second preset time is 120 min to 150 min.

[0034] It should be noted that the high-temperature and long-term curing reaction allows the vinyl silicone resin modified with polyurethane groups to be fully cross-linked, thereby improving the bonding strength between the semi-cured fluorescent sheet 30 and the flip-chip LED chip 2 and the bracket 1, forming a dense and stable structure, enhancing the mechanical strength and environmental interference resistance of the LED packaging device, extending the service life of the LED packaging device, and improving the long-term reliability of the LED packaging device.

[0035] Step S14: encapsulating the cured product with transparent adhesive to obtain an LED package device.

[0036] Furthermore, the material of the transparent adhesive 4 includes vinyl phenyl silicone resin, and the refractive index of the transparent adhesive 4 is 1.47-1.49.

[0037] It should be noted that the low-refractive-index transparent adhesive 4, acting as an outer layer, complements the high-refractive-index semi-cured phosphor sheet 30 as an inner layer. This gradient of refractive index guides the direction of light emission, controlling the angle of light. This allows both high- and low-angle light to escape more easily, compensating for the insufficient control of light at different angles provided by a single layer of transparent adhesive 4 and creating a more efficient light extraction path. Furthermore, the flip-chip LED chip 2 (such as a blue-violet LED chip) has a high refractive index. As light travels from the flip-chip LED chip 2 to the transparent adhesive 4 and then to the air, it is susceptible to total internal reflection due to the refractive index difference, trapping the light within the flip-chip LED chip 2. The low-refractive-index transparent adhesive 4 (matching the refractive index of the flip-chip LED chip 2 and air) reduces the refractive index difference between the flip-chip LED chip 2, the transparent adhesive 4, and the air, lowering the probability of total internal reflection and allowing more light to escape from the sides and surface of the flip-chip LED chip 2. This improves light extraction efficiency, particularly significantly optimizing light exiting from the sides of the flip-chip LED chip 2.

[0038] Correspondingly, the present invention further provides an LED packaging device, which is prepared by the above-mentioned method for preparing the LED packaging device.

[0039] In addition, the present invention also provides an application of the above-mentioned LED packaging device in the fields of display, backlight, and lighting.

[0040] The technical solution of the present invention is described in detail below with reference to specific embodiments.

[0041] Example 1 A first embodiment of the present invention provides a method for manufacturing an LED package device, the method comprising steps S10 to S14.

[0042] Step S10, mixing the encapsulated silica gel and the phosphor according to a preset ratio, and then using a scraping machine to form a film of a preset thickness; The encapsulated silica gel includes vinyl silicone resin and polyurethane resin, the molecular weight of the polyurethane group in the polyurethane resin is 6000, and the mass of the polyurethane resin is 40% of the mass of the vinyl silicone resin.

[0043] Furthermore, in the film, the mass percentage of the phosphor is 50%.

[0044] Furthermore, the preset thickness of the membrane is 100 μm.

[0045] Step S11, curing the film at a first preset temperature for a first preset time to complete a primary curing to obtain a semi-cured phosphor sheet; Furthermore, the first preset temperature is 100° C., the first preset time is 3 minutes, and the refractive index of the semi-cured fluorescent sheet is 1.50-1.52.

[0046] Preferably, the semi-cured fluorescent sheet is in a square shape, and the side length of the semi-cured fluorescent sheet is the sum of twice the height of the flip-chip LED chip and the side length.

[0047] Step S12, transferring the semi-cured phosphor sheet to the flip-chip LED chip that has been die-bonded in the bracket, and vacuum pressing it so that the semi-cured phosphor sheet is completely attached to the surface and side surfaces of the flip-chip LED chip; Specifically, the vacuum deposition conditions are: -0.9 atm, temperature 160° C., and time 240 s.

[0048] Step S13, curing the vacuum pressed semi-cured phosphor sheet at a second preset temperature for a second preset time to complete secondary curing to obtain a cured product; Furthermore, the second preset temperature is 160° C., and the second preset time is 140 minutes.

[0049] Step S14: encapsulating the cured product with transparent adhesive to obtain an LED package device.

[0050] Furthermore, the material of the transparent adhesive includes vinyl phenyl silicone resin, and the refractive index of the transparent adhesive is 1.47-1.49.

[0051] Example 2 A second embodiment of the present invention provides a method for manufacturing an LED package device. The method for manufacturing the LED package device in this embodiment differs from the method for manufacturing the LED package device in the first embodiment in that: The preset thickness of the membrane is 80 μm.

[0052] Example 3 A third embodiment of the present invention provides a method for manufacturing an LED package device. The method for manufacturing the LED package device in this embodiment differs from the method for manufacturing the LED package device in the first embodiment in that: The preset thickness of the membrane is 120 μm.

[0053] Example 4 A fourth embodiment of the present invention provides a method for manufacturing an LED package device. The method for manufacturing the LED package device in this embodiment differs from the method for manufacturing the LED package device in the first embodiment in that: The first preset temperature is 80°C.

[0054] Example 5 A fifth embodiment of the present invention provides a method for manufacturing an LED package device. The method for manufacturing the LED package device in this embodiment differs from the method for manufacturing the LED package device in the first embodiment in that: The first preset temperature is 120°C.

[0055] Example 6 A sixth embodiment of the present invention provides a method for manufacturing an LED package device. The method for manufacturing the LED package device in this embodiment differs from the method for manufacturing the LED package device in the first embodiment in that: The first preset time is 2 minutes.

[0056] Example 7 A seventh embodiment of the present invention provides a method for manufacturing an LED package device. The method for manufacturing the LED package device in this embodiment differs from the method for manufacturing the LED package device in the first embodiment in that: The first preset time is 4 minutes.

[0057] Example 8 An eighth embodiment of the present invention provides a method for manufacturing an LED package device. The method for manufacturing the LED package device in this embodiment differs from the method for manufacturing the LED package device in the first embodiment in that: The first preset time is 5 minutes.

[0058] Comparative Example 1 The first comparative example of the present invention provides a method for preparing an LED package device. The difference between the method for preparing the LED package device in this comparative example and the method for preparing the LED package device in the first embodiment is that: The product is encapsulated by dispensing process and then solidified.

[0059] Comparative Example 2 The second comparative example of the present invention provides a method for preparing an LED package device. The difference between the method for preparing the LED package device in this comparative example and the method for preparing the LED package device in the first embodiment is that: The preset thickness of the membrane is 60 μm.

[0060] Comparative Example 3 A third comparative example of the present invention provides a method for preparing an LED package device. The method for preparing the LED package device in this comparative example differs from the method for preparing the LED package device in the first embodiment in that: The preset thickness of the membrane is 140 μm.

[0061] Comparative Example 4 A fourth comparative example of the present invention provides a method for preparing an LED package device. The method for preparing the LED package device in this comparative example differs from the method for preparing the LED package device in the first embodiment in that: The first preset temperature is 60°C.

[0062] Comparative Example 5 A fourth comparative example of the present invention provides a method for preparing an LED package device. The method for preparing the LED package device in this comparative example differs from the method for preparing the LED package device in the first embodiment in that: The first preset time is 1 minute.

[0063] Please refer to Table 1 below, which shows the parameters corresponding to the above embodiments and comparative examples of the present invention.

[0064] Table 1:

[0065] The 3-step region refers to a collection of LED packaged devices whose color coordinates fall within the 3-step MacAdam ellipse. This indicates that the color tolerance of this batch of LED packaged devices is controlled within the 3-step standard. The human eye can hardly perceive the color difference, which is a key indicator of color consistency after LED packaging. In addition, the brightness improvement rate is calculated based on the brightness of Comparative Example 1.

[0066] From the comparison of the data in Table 1, it can be seen that the double curing of this embodiment forms a stable and uniform phosphor sheet bonded to the flip-chip LED chip, which can effectively improve the brightness and concentration of the LED package device.

[0067] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0068] The above-described embodiments merely illustrate several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for preparing an LED package device, characterized in that: The preparation method comprises: The encapsulated silica gel and phosphor are mixed in a preset ratio, and then a film with a preset thickness is prepared by a scraping machine; curing the film at a first preset temperature for a first preset time to complete a primary curing to obtain a semi-cured fluorescent sheet; Transferring the semi-cured phosphor sheet to the flip-chip LED chip that has been crystal-bonded in the bracket, and vacuum pressing it so that the semi-cured phosphor sheet is completely attached to the surface and side of the flip-chip LED chip; Curing the vacuum pressed semi-cured fluorescent sheet at a second preset temperature for a second preset time to complete secondary curing to obtain a cured product; The cured product is encapsulated with transparent adhesive to obtain an LED package device.

2. The method for preparing an LED package device according to claim 1, wherein: The encapsulated silica gel comprises vinyl silicone resin and polyurethane resin, the molecular weight of the polyurethane group in the polyurethane resin is 2000-10000, and the mass of the polyurethane resin is 30%-50% of the mass of the vinyl silicone resin.

3. The method for preparing an LED package device according to claim 2, wherein: In the film, the mass percentage of the phosphor is 20% to 80%.

4. The method for preparing an LED package device according to claim 1, wherein: The preset thickness is 80 μm to 120 μm.

5. The method for preparing an LED package device according to claim 1, wherein: The first preset temperature is 80° C. to 120° C., the first preset time is 2 min to 5 min, and the refractive index of the semi-cured fluorescent sheet is 1.50 to 1.

52.

6. The method for preparing an LED package device according to claim 1, wherein: The semi-cured fluorescent sheet is in a square shape, and the side length of the semi-cured fluorescent sheet is the sum of twice the height of the flip-chip LED chip and the side length.

7. The method for preparing an LED package device according to claim 1, wherein: The second preset temperature is 150° C. to 170° C., and the second preset time is 120 min to 150 min.

8. The method for preparing an LED package device according to claim 1, wherein: The material of the transparent adhesive includes vinyl phenyl silicone resin, and the refractive index of the transparent adhesive is 1.47-1.

49.

9. An LED package device, characterized in that: The LED package device is prepared by the method for preparing an LED package device according to any one of claims 1 to 8.

10. Application of the LED package device according to claim 9 in the fields of display, backlight and lighting.

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