Light source module packaging method and light source module

Abstract

The invention provides a light source module packaging method and a light source module, and the method comprises the steps: enabling a wafer to be directly disposed on a packaging bonding pad in an inverted manner, enabling the electrical connection surface of the wafer to face downwards, enabling the electrical connection surface to be directly in contact with the packaging bonding pad on a substrate, enabling the electrical connection surface to be in welding connection with the packaging bonding pad, and enabling the heat to be directly transmitted to the substrate from the wafer through the packaging bonding pad. The heat conduction efficiency is remarkably improved, and a good heat dissipation effect can be kept while a metal radiator is omitted; moreover, the array lens is placed according to the mode that the opening of the optical cavity faces upwards, the prepared fluorescent glue is filled in each optical cavity of the array lens, and the substrate provided with the wafer is inversely buckled above the array lens filled with the fluorescent glue, so that the method can effectively eliminate an air layer, and the yield of the array lens is improved. And silica gel with poor long-term thermal stability does not need to be additionally filled, so that the light emitting effect of the light source module is enhanced, and the service life of the light source module is prolonged.

Description

Technical Field

[0001] The present application relates to the field of light sources, and in particular to a light source module packaging method and a light source module. Background Art

[0002] Light source packaging involves combining light-emitting components with other necessary supporting components (such as circuit boards and lenses) through specific processes to create a complete light source module. Light source packaging not only protects the light-emitting components but also directly impacts multiple aspects of the light source, such as its optical properties and thermal management. Therefore, optimizing the light source packaging process can improve the lighting quality and reliability of the light source under the intended operating environment.

[0003] In traditional light source packaging, there is usually an air layer between the lens and the fluorescent encapsulation glue. This air layer will cause light reflection and refraction, thereby reducing the light transmittance and affecting the brightness and optical performance of the light source. In addition, because the air layer isolates the direct transfer of heat, the heat cannot be efficiently transferred from the light-emitting unit to the heat sink or other heat dissipation materials, causing the light source module to overheat during operation. In severe cases, it will affect the service life and stability of the light source module.

[0004] To remove the air layer, traditional packaging technology uses a method of injecting silicone gel into the air layer. The silicone gel is filled between the lens and the fluorescent encapsulant, effectively filling the gap, thereby removing the air layer in the optical cavity and ensuring smoother light and heat transmission. However, the silicone gel filling method increases the complexity of the light source packaging process. Due to the high temperature generated by the light source during operation, the small molecules in the silicone gel are easily volatilized or overflowed, resulting in cavitation within the packaging wall. This not only affects the structural stability of the light source module and can re-create the air layer problem, but also the volatile substances of the silicone gel can adhere to the outer surface of the light source module, causing contamination.

[0005] Traditional light source module assembly methods typically utilize upright chip assembly. In this method, the positive and negative electrodes of the wafer chip face upward and are connected to the (circuit) substrate via gold wires before being packaged. With this packaging method, the positive and negative electrodes of the wafer chip face upward, and a large portion of the heat generated by the wafer chip during operation must be transferred to the packaging substrate via the gold wires. However, due to the extremely thin diameter of the gold wires, the heat conduction efficiency is low, resulting in poor heat dissipation of the wafer chip within the overall package.

[0006] In summary, filling with silicone gel will lead to the complexity of the packaging process and reduce the luminous effect and service life of the light source module. The thermal conduction and heat dissipation effect of the upright wafer chip is poor, and an additional metal heat sink is required to improve the overall heat dissipation effect. In addition, the reliability of gold wire welding is lower than that of flip-chip packaging. Summary of the Invention

[0007] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a light source module packaging method and a light source module to solve the above-mentioned problems.

[0008] To achieve the above-mentioned purpose and other related purposes, the first aspect of the present application provides a light source module packaging method, comprising: arranging circuit wires, input pads and a plurality of packaging pads on one side of a substrate, and arranging a plurality of optical cavities on an array lens, wherein the packaging pads correspond to the optical cavities one-to-one; arranging a plurality of wafers correspondingly on the packaging pads; placing the array lens with the opening of the optical cavity facing upward, and filling the configured fluorescent glue into each optical cavity of the array lens, wherein after filling, the fluorescent glue fills the optical cavity and is higher than the edge of the opening of the optical cavity; placing the substrate with the wafers inverted above the array lens filled with the fluorescent glue, so that the wafers are accommodated in the optical cavity, wherein each of the wafers corresponds to each optical cavity one-to-one; and fixing the combined substrate and the array lens.

[0009] In an embodiment of the first aspect of the present application, the configuration method of the fluorescent glue includes: preparing a combination phosphor whose light-emitting band matches the wafer, wherein the combination phosphor includes a phosphor with a green light-emitting band, a phosphor with a yellow light-emitting band, and a phosphor with a red light-emitting band; mixing the combination phosphor with a two-component transparent addition-type phenyl organic silicone to make a fluorescent glue.

[0010] In an embodiment of the first aspect of the present application, after the composite phosphor and two-component transparent addition-type phenyl organic silica gel are mixed and stirred to prepare fluorescent glue, nanoparticles are added to the fluorescent glue.

[0011] In an embodiment of the first aspect of the present application, the wafer is fixed to the packaging pad by a die-bonding material in a flip-chip manner.

[0012] In an embodiment of the first aspect of the present application, the combined substrate and the array lens are fixed by screws and / or heat curing.

[0013] In an embodiment of the first aspect of the present application, the heating and curing method includes placing the combined substrate and the array lens into an oven.

[0014] In an embodiment of the first aspect of the present application, components of the substrate include aluminum oxide, a sintering aid, an organic matter, and a dispersant.

[0015] In an embodiment of the first aspect of the present application, the material of the array lens includes high-transmittance polycarbonate.

[0016] In an embodiment of the first aspect of the present application, a self-cleaning coating is coated on the outer surface of the optical cavity of the array lens.

[0017] To achieve the above-mentioned object and other related objects, a second aspect of the present application provides a light source module, which is obtained according to any of the above-mentioned methods.

[0018] As described above, the present application has the following beneficial effects:

[0019] The present invention provides a light source module packaging method, which directly flips the wafer and sets it on the packaging pad, so that the electrical connection surface of the wafer faces downward, and the electrical connection surface directly contacts the packaging pad on the substrate and is welded to each other. Heat is directly conducted from the wafer to the substrate through the packaging pad. Compared with the upright chip, although the contact area between the wafer and the substrate of the flip-chip is relatively small, because heat can be directly transferred to the substrate through the packaging pad, the heat conduction efficiency is significantly improved, and a good heat dissipation effect can be maintained while omitting a metal heat sink.

[0020] Furthermore, the present invention positions the array lens with the opening of the optical cavity facing upward, and fills each optical cavity of the array lens with a prepared fluorescent glue. After filling, the fluorescent glue fills the optical cavity and protrudes above the edge of the optical cavity opening. The substrate with the wafer mounted thereon is then inverted over the array lens filled with fluorescent glue, so that the wafer is accommodated within the optical cavity and the combined substrate and array lens are fixed. This method effectively eliminates the air layer and eliminates the need for additional filling with silicone gel, which has poor thermal properties, thereby enhancing the luminous effect of the light source module and extending its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Shown is a top view of a light source module in one embodiment of the present application.

[0022] Figure 2 Display as Figure 1 Schematic diagram of the structure of area A in the middle.

[0023] Figure 3 Shown is a side cross-sectional view of a light source module in one embodiment of the present application Figure 1 .

[0024] Figure 4 Display as Figure 3 Schematic diagram of the structure of area B in the middle.

[0025] Figure 5 Shown is a side cross-sectional view of a light source module in one embodiment of the present application Figure 2 .

[0026] Component number description

[0027] Substrate 1

[0028] Circuit wire 2

[0029] Package pad 3

[0030] Input pad 4

[0031] Array lens 5

[0032] Optical cavity 6

[0033] Wafer 7

[0034] Screw 8 DETAILED DESCRIPTION

[0035] The following describes the embodiments of the present application through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless they conflict.

[0036] In the embodiments of the present application, terms such as "first" and "second" are used to distinguish between identical or similar items with substantially the same functions and effects. For example, the first XX and the second XX are merely used to distinguish between different XXs and do not limit their order. Those skilled in the art will understand that terms such as "first" and "second" do not limit the quantity or order of execution, and that terms such as "first" and "second" do not necessarily mean that they are different.

[0037] It should be noted that in the embodiments of this application, words such as "exemplary" or "for example" represent examples, illustrations, or descriptions. Any embodiment or design described in this application as "exemplary" or "for example" should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0038] In the embodiments of the present application, "at least one" refers to one or more, and "more" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can represent: a, b, c, ab, ac, bc or abc, where a, b, c can be single or multiple.

[0039] like Figure 1-4 As shown, a light source module packaging method of the present invention includes the following steps:

[0040] S1: circuit conductors 2, input pads 4 and several package pads 3 are arranged on one side of a substrate 1, and several optical cavities 6 are arranged on an array lens 5, wherein the package pads 3 correspond to the optical cavities 6 one by one.

[0041] It should be understood that the circuit conductor 2 is a basic component in the electrical connection, usually made of copper wire. The circuit conductor 2 transfers electrical energy from one electrical component to another to ensure that the current can flow through all components such as the wafer 7, so that the light source can work normally. The input pad 4 is an electrical connection point for receiving external power or signal input. In the light source module, the input pad 4 is usually connected to the power supply or control circuit to provide the necessary current signal for the components on the substrate 1. It is usually located on one side of the substrate 1 and is connected to the circuit conductor 2 by welding or other means. The package pad 3 refers to the electrical connection point between the wafer 7 and the substrate 1, ensuring that the wafer 7 can stably obtain current from the substrate 1 through the connection point to achieve luminescence of the light source.

[0042] The packaging pads 3 are aligned one-to-one with the optical cavities 6 of the array lens 5 , so that each wafer 7 can be correspondingly accommodated in each optical cavity 6 after being fixedly connected to the packaging pads 3 , thereby emitting light outward through the optical cavity 6 .

[0043] In an embodiment of the first aspect of the present application, components of the substrate 1 include aluminum oxide, a sintering aid, an organic matter, and a dispersant.

[0044] Substrate 1 is preferably made of a ceramic material, composed of alumina, a sintering aid, an organic compound, and a dispersant. Alumina provides excellent heat dissipation, insulation, and mechanical strength, ensuring stable and efficient heat dissipation during operation of the light source module. The sintering aid optimizes the sintering process of the ceramic material, increasing the density and mechanical strength of the ceramic substrate 1. The organic compound helps shape and bond the ceramic powder during production, ensuring that the substrate 1 has the proper structure and strength before sintering. The dispersant ensures uniform distribution of the ceramic powder, improving sintering performance and the quality of the final product. These components work together to ensure the excellent performance of the ceramic substrate 1, meeting the heat dissipation, stability, and reliability requirements of the light source module.

[0045] In an embodiment of the first aspect of the present application, the material of the array lens 5 includes high-transmittance polycarbonate.

[0046] In the light source module, the array lens 5 is usually used to adjust the light beam direction and spot shape of the light source, so the material of the lens is crucial to the optical performance. First, high-transmittance polycarbonate has a high light transmittance, usually reaching 88% to 90% or more, which gives it a strong application advantage in the optical field, especially in situations where precise control of the light beam direction and scattering is required. Since the array lens 5 in the light source module is required to be able to efficiently transmit the light emitted by the light source, high-transmittance polycarbonate can effectively ensure the output efficiency of the light. Secondly, the polycarbonate material has good processability and can be formed into various complex shapes through processes such as injection molding, extrusion, and hot pressing. Since the main function of the lens is to control the propagation direction, spot size and uniformity of light, the excellent processability of high-transmittance polycarbonate allows it to be manufactured into precise optical cavities 6 and lens shapes, thereby improving the control of the light beam and ensuring that the light source module can achieve the predetermined optical effect. Furthermore, high-transmittance polycarbonate maintains stable optical performance and mechanical strength even in high-temperature environments. Light source modules, especially high-power ones, generate significant heat during operation, and lens materials must be able to withstand high temperatures without deformation or damage. Polycarbonate exhibits excellent thermal stability and can maintain stable performance within a certain temperature range. Therefore, lenses incorporating high-transmittance polycarbonate effectively control light transmission and ensure that light source modules maintain efficient and stable performance over extended periods of use.

[0047] In an embodiment of the first aspect of the present application, a self-cleaning coating is coated on the outer surface of the optical cavity 6 of the array lens 5 .

[0048] A self-cleaning coating is a special functional coating, usually based on nanotechnology or surface chemical treatment, which enables the coated surface to have the ability to self-clean. Since the self-cleaning coating has a certain anti-fouling ability, it can prevent external pollutants such as grease, dust, stains, etc. from forming stable adhesion on the surface, maintaining the cleanliness and optical properties of the surface. In the light source module package, the array lens 5 is usually used to control the direction and shape of the light beam of the light source. Since the lens surface needs to be exposed to the light source working environment for a long time, they are easily contaminated by dust, stains, grease and moisture, resulting in a decrease in optical performance and affecting the propagation and lighting effect of the light beam. Therefore, by setting a self-cleaning coating, it is possible to effectively prevent the adhesion of dust, stains and moisture, ensure that the array lens 5 remains clean for a long time, reduce optical attenuation caused by pollution, improve optical efficiency and extend service life.

[0049] S2: several wafers 7 are arranged correspondingly on the packaging pads 3 .

[0050] In an embodiment of the first aspect of the present application, the wafer 7 is fixed to the packaging pad 3 by a die-bonding material in a flip-chip manner.

[0051] In a flip-chip package, the positive and negative terminals (electrical connection surfaces) of LED wafer 7 face downward, directly contacting substrate 1. This allows heat to be more directly transferred from wafer 7 to substrate 1, and then dissipated to the outside world through substrate 1. Compared to traditional face-up chips, which use gold wires for heat conduction, flip-chips avoid the thermal resistance caused by the poor thermal conductivity of gold wires. Heat can be transferred to substrate 1 over a larger area, improving heat conduction efficiency. Therefore, even without the traditional metal heat sink, satisfactory heat dissipation can be achieved.

[0052] S3: Place the array lens 5 with the opening of the optical cavity 6 facing upward, and fill the configured fluorescent glue into each optical cavity 6 of the array lens 5, wherein after filling, the fluorescent glue fills the optical cavity 6 and is higher than the edge of the opening of the optical cavity 6.

[0053] S4: The substrate 1 provided with the wafer 7 is placed upside down on the array lens 5 filled with fluorescent glue, so that the wafer 7 is accommodated inside the optical cavity 6, wherein each wafer 7 corresponds to each optical cavity 6 one by one.

[0054] In conventional light source module packaging methods, wafer 7 is typically first fixed to substrate 1, then encapsulated with fluorescent encapsulation glue. The array lens 5 is then placed over the encapsulated wafer 7, and finally, silicone gel is injected between the lens and the fluorescent encapsulation glue to eliminate the air layer. In the method provided by the present invention, however, by inverting the array lens 5, filling the optical cavity 6 of the array lens 5 with fluorescent glue, and then aligning the substrate 1 and array lens 5 with wafer 7 facing the opening of the optical cavity 6, the two are then fixed together. This directly eliminates the air layer and eliminates the traditional silicone gel injection process, making the packaging method more streamlined.

[0055] In an embodiment of the first aspect of the present application, the configuration method of the fluorescent glue includes: preparing a combination phosphor whose light-emitting band matches the wafer 7, wherein the combination phosphor includes a phosphor with a green light-emitting band, a phosphor with a yellow light-emitting band, and a phosphor with a red light-emitting band; mixing the combination phosphor with a two-component transparent addition-type phenyl organic silicone to make a fluorescent glue.

[0056] It should be understood that phosphors emitting green typically absorb blue or ultraviolet light, emitting green; phosphors emitting yellow absorb blue or ultraviolet light, emitting yellow; and phosphors emitting red absorb blue or ultraviolet light, emitting red. By combining these phosphors emitting green, yellow, and red light, a composite phosphor is created, ensuring that the final light source meets specific color temperature requirements (such as 4000K) and optimizes spectral characteristics. This combination also improves the optical efficiency and color uniformity of the light source. Two-component transparent, addition-type organic silicone rubber consists of a main adhesive component and a curing agent component. When mixed, these two components undergo an addition reaction to form the final silicone material. The phenyl groups in the rubber provide excellent thermal stability and electrical insulation, as well as strong UV resistance. Therefore, fluorescent adhesives incorporating two-component transparent, addition-type organic silicone rubber can offer higher transparency, reduced light loss, and improved thermal conductivity.

[0057] In an embodiment of the first aspect of the present application, after the composite phosphor and two-component transparent addition-type phenyl organic silica gel are mixed and stirred to prepare fluorescent glue, nanoparticles are added to the fluorescent glue.

[0058] Nanoparticles have very good thermal conductivity. When added to fluorescent glue, the nanoparticles can help transfer heat from the LED chip to the heat dissipation substrate 1 more quickly, thus preventing the LED chip from being damaged due to overheating and improving heat dissipation efficiency. In addition, nanoparticles can improve the mechanical strength of the fluorescent glue, enhance the compressive strength, impact resistance and fatigue resistance of the colloid. The fluorescent glue with nanoparticles added will be stronger than ordinary fluorescent glue, enhancing the ability of the light source package to resist the influence of the external environment. Especially during transportation and use, the module is not easily damaged by vibration or external force impact. In addition, since nanoparticles can perform a microscopic scattering effect on light, they can also enhance the uniformity and expansibility of light, reducing the waste or uneven distribution of light.

[0059] S5: Fixing the combined substrate 1 and the array lens 5.

[0060] In an embodiment of the first aspect of the present application, the combined substrate 1 and the array lens 5 are fixed by screws 8 and / or heat curing.

[0061] The fixing method of screw 8 can provide a strong mechanical connection force to ensure that the substrate 1 and the array lens 5 firmly maintain relative positions during the installation process, and avoid loosening or displacement of the components due to external force or vibration, for example, Figure 5 As shown, the connection between the ceramic substrate 1 and the array lens 5 is achieved through countersunk screw holes 8 provided on the back of the ceramic substrate 1 and corresponding screws 88 on the lens. This screw connection provides a strong mechanical bond, ensuring a secure fixation between the two and preventing loosening of the module due to vibration or external forces during use. Furthermore, the stability of the screw connection ensures a secure and reliable contact between the ceramic substrate 1 and the lens, making it less likely to experience performance degradation or module failure due to poor contact over long periods of operation.

[0062] The heat curing method heats the assembled components so that the packaging material, such as glue or silicone, forms a strong chemical bond with the substrate 1 and the lens during the curing process, further enhancing the adhesion and stability between the components.

[0063] The heat-curing method uses heat to promote chemical reactions in the encapsulation material, causing the material to transform from a liquid to a solid during the curing process. During the heating process, the chemical components in the glue or silicone begin to react with the active groups on the substrate 1 and lens surface, forming a cross-linked structure. This process gives the encapsulation material stronger physical adhesion, effectively securing the substrate 1, optical lens, and other components together. Furthermore, because the heating process makes the molecular chains in the glue or silicone more active, forming stronger chemical bonds with the substrate 1 and lens surface, the heat-curing method helps to improve the adhesion strength between the encapsulation material and the substrate 1 and lens. Furthermore, the heat-cured encapsulation material can better conduct heat generated by the LED chip to the heat-dissipating substrate 1, effectively reducing the temperature and preventing LED chip failure due to overheating. The denser structure of the heat-cured material avoids thermal resistance caused by bubbles or uneven curing, improving overall heat dissipation and reducing light decay caused by high temperatures.

[0064] In an embodiment of the first aspect of the present application, the heating and curing method includes placing the combined substrate 1 and the array lens 5 into an oven.

[0065] The oven can provide a uniform thermal environment, ensuring that all packaging materials are evenly heated during the curing process. Through the temperature control system, the oven can maintain a constant heating temperature, so that the packaging materials are evenly cured, avoiding uneven curing caused by temperature differences. Compared with other heating methods (such as hot air or hot plates), the all-round heat source in the oven can avoid the problem of local overheating, ensuring that the materials will not over-react or deteriorate due to high temperature during the packaging process. In addition, due to the closed design of the oven, the high temperature during the heating process can be effectively controlled, avoiding the impact of temperature fluctuations in the external environment on the curing process. The even distribution of heat inside the oven also reduces the safety risks caused by local overheating.

[0066] To achieve the above-mentioned object and other related objects, a second aspect of the present application provides a light source module, which is obtained according to any of the above-mentioned methods.

[0067] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

[0068] In summary, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0069] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be covered by the claims of this application.

Claims

1. A light source module packaging method, characterized in that: include: A circuit conductor (2), an input pad (4), and a plurality of package pads (3) are arranged on one side of a substrate (1); and a plurality of optical cavities (6) are arranged on an array lens (5), wherein the package pads (3) correspond to the optical cavities (6) in a one-to-one manner; Placing a plurality of wafers (7) correspondingly on the packaging pads (3); The array lens (5) is placed in a manner such that the opening of the optical cavity (6) faces upward, and the prepared fluorescent glue is filled into each optical cavity (6) of the array lens (5), wherein after filling, the fluorescent glue fills the optical cavity (6) and is higher than the edge of the opening of the optical cavity (6); The substrate (1) provided with the wafer (7) is placed upside down on the array lens (5) filled with fluorescent glue, so that the wafer (7) is accommodated inside the optical cavity (6), wherein each wafer (7) corresponds to each optical cavity (6) on a one-to-one basis; The combined substrate (1) and the array lens (5) are fixed.

2. The light source module packaging method according to claim 1, wherein: The configuration method of the fluorescent glue includes: Prepare a combination phosphor whose luminescence wavelength matches the wafer (7), wherein the combination phosphor includes a phosphor whose luminescence wavelength is green, a phosphor whose luminescence wavelength is yellow, and a phosphor whose luminescence wavelength is red; The composite phosphor is mixed with a two-component transparent addition-type phenyl organic silica gel to prepare a fluorescent glue.

3. The light source module packaging method according to claim 1, wherein: After the composite phosphor and two-component transparent addition-type phenyl organic silica gel are mixed and stirred to prepare fluorescent glue, nanoparticles are added into the fluorescent glue.

4. The light source module packaging method according to claim 1, wherein: The wafer (7) is fixed to the packaging pad (3) by a flip-chip method through a die-bonding material.

5. The light source module packaging method according to claim 1, wherein: The combined substrate (1) and the array lens (5) are fixed by screws (8) and / or by heat curing.

6. The light source module packaging method according to claim 5, characterized in that: The heating and curing method includes placing the combined substrate (1) and the array lens (5) into an oven.

7. The light source module packaging method according to claim 1, characterized in that: The components of the substrate (1) include aluminum oxide, a sintering aid, organic matter and a dispersant.

8. The light source module packaging method according to claim 1, wherein: The material of the array lens (5) includes high-transmittance polycarbonate.

9. The light source module packaging method according to claim 1, wherein: A self-cleaning coating is applied to the outer surface of the optical cavity (6) of the array lens (5).

10. A light source module, characterized in that: The light source module is obtained according to the method according to any one of claims 1-9.

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