A UV LED device and manufacturing method thereof

Abstract

The present application discloses a UV LED device, including a substrate with a metal coating on the surface; a eutectic alloy layer located at a preset position on the upper surface of the substrate; an aluminum bowl connected to the substrate through the eutectic alloy layer; a UV LED chip located in the aluminum bowl area and eutectic connected to the upper surface of the substrate; and a cover. The UV LED device in the present application includes a substrate with a metal coating on the surface, a eutectic alloy layer, an aluminum bowl, a UV LED chip and a cover. The bowl is an aluminum bowl, which has a high reflectivity and can reduce the absorption of ultraviolet light, thereby increasing the utilization rate of ultraviolet light by the UV LED device. The aluminum bowl is connected to the substrate by the eutectic alloy layer, which can effectively reduce the void rate between the aluminum bowl and the substrate. The aluminum bowl is directly connected to the substrate through the eutectic alloy layer, thereby improving the manufacturing efficiency. The present application also provides a method for manufacturing a UV LED device with the above advantages.

Description

Technical Field

[0001] The present application relates to the field of LED technology, and in particular to a UV LED device and a manufacturing method thereof. Background Art

[0002] UV LED, or ultraviolet light-emitting diode, is a type of LED. Its light source has the advantages of environmental protection, low power consumption and selectable wavelengths, and is widely used in printing, handicrafts, and medical fields. In current UV LED devices, a copper cup is electroplated on the substrate, and a gold coating is distributed on the surface of the substrate and the copper cup. The UV LED chip is located within the copper cup and is electrically connected to the substrate. Since gold has a very low reflectivity to ultraviolet light, most of the light is absorbed by the gold coating on the surface material, resulting in a generally very low utilization rate of ultraviolet light in UV LED devices. In addition, the void rate of the copper cup and the substrate of existing UV LED devices is also relatively high. At the same time, the formation of the copper cup requires multiple copper electroplatings, which is time-consuming, has low production efficiency, and is costly.

[0003] Therefore, how to solve the above technical problems should be the focus of technical personnel in this field. Summary of the invention

[0004] The purpose of this application is to provide a UV LED device and a manufacturing method thereof, so as to improve the utilization rate of ultraviolet light by the UV LED device, reduce the void rate, and improve production efficiency.

[0005] In order to solve the above technical problems, the present application provides a UV LED device, comprising:

[0006] A substrate having a metal coating distributed on the surface;

[0007] a eutectic alloy layer located at a preset position on the upper surface of the substrate;

[0008] An aluminum bowl connected to the substrate via the eutectic alloy layer;

[0009] A UV LED chip located in the aluminum bowl region and eutectically connected to the upper surface of the substrate;

[0010] Capping.

[0011] Optionally, the substrate is an aluminum nitride ceramic substrate.

[0012] Optionally, the cover is a quartz glass cover.

[0013] Optionally, the eutectic alloy layer is a gold-tin alloy layer.

[0014] Optionally, the metal plating is a gold plating.

[0015] Optionally, the UV LED chip is a UV C LED chip.

[0016] The present application also provides a UV LED device manufacturing method, comprising:

[0017] Obtaining a substrate with a metal coating distributed on the surface;

[0018] Forming a eutectic alloy layer in the area where the aluminum cup is connected to the substrate;

[0019] Performing eutectic welding on the substrate and the aluminum cup through the eutectic alloy layer at a first temperature;

[0020] Eutectic soldering a UV LED chip on the upper surface of the substrate at a second temperature, wherein the UV LED chip is located in the aluminum bowl region, and the second temperature is lower than the first temperature;

[0021] A cover is connected to the surface of the aluminum bowl facing away from the substrate.

[0022] Optionally, connecting the cover to the surface of the aluminum bowl facing away from the substrate comprises:

[0023] The cover is connected to the surface of the aluminum bowl facing away from the substrate by using an adhesive method or a eutectic welding method.

[0024] Optionally, after eutectic welding the substrate and the aluminum cup through the eutectic alloy layer, the method further includes:

[0025] The void ratios of the aluminum bowl and the substrate are detected.

[0026] Optionally, obtaining a substrate having a metal coating distributed on the surface includes:

[0027] The substrate is prepared by using a DPC process;

[0028] A metal coating is plated on the upper surface of the substrate.

[0029] A UV LED device provided in the present application includes: a substrate with a metal coating distributed on the surface; a eutectic alloy layer located at a preset position on the upper surface of the substrate; an aluminum bowl connected to the substrate via the eutectic alloy layer; a UV LED chip located in the aluminum bowl area and eutectically connected to the upper surface of the substrate; and a cover.

[0030] It can be seen that the UV LED device in the present application includes a substrate with a metal coating on the surface, a eutectic alloy layer, an aluminum bowl, a UV LED chip and a cover. The bowl is an aluminum bowl, which has a high reflectivity and can reduce the absorption of ultraviolet light, thereby increasing the utilization rate of ultraviolet light by the UV LED device. The aluminum bowl and the substrate are connected by the eutectic alloy layer, which can effectively reduce the void rate between the aluminum bowl and the substrate. In addition, the aluminum bowl is directly connected to the substrate through the eutectic alloy layer, which greatly improves the production efficiency and has high production capacity. In addition, the present application also provides a method for manufacturing a UV LED device with the above advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 A schematic diagram of the structure of a UV LED device provided in an embodiment of the present application;

[0033] Figure 2 A schematic diagram of the structure of an aluminum bowl cup provided in an embodiment of the present application;

[0034] Figure 3 This is a schematic diagram of the bottom of an aluminum bowl;

[0035] Figure 4 This is a schematic diagram of the structure when the UV LED chip is inverted;

[0036] Figure 5 A flow chart of a UV LED device manufacturing method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0038] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0039] As described in the background technology section, in current UV LED devices, a copper bowl is plated on the substrate, and a gold plating layer is distributed on the surface of the substrate and the copper bowl. The reflectivity of gold to ultraviolet light is very low, resulting in a generally very low utilization rate of ultraviolet light in UV LED devices. In addition, the void rate of the copper bowl and the substrate of existing UV LED devices is also relatively high. At the same time, the formation of the copper bowl requires multiple copper electroplatings, and the thickness of the copper is only 60 microns after one copper electroplating, resulting in low production efficiency and high cost.

[0040] In view of this, the present application provides a UV LED device, please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a UV LED device provided in an embodiment of the present application, and the UV LED device includes:

[0041] A substrate 1 having a metal coating 2 distributed on the surface;

[0042] a eutectic alloy layer 3 located at a preset position on the upper surface of the substrate 1;

[0043] An aluminum bowl 4 connected to the substrate 1 through the eutectic alloy layer 3;

[0044] A UV LED chip 5 located in the aluminum bowl 4 and eutectically connected to the upper surface of the substrate 1;

[0045] Cap 6.

[0046] Optionally, the substrate 1 is an aluminum nitride ceramic substrate 1 , but the present application does not specifically limit this, and the substrate 1 may also be an aluminum oxide ceramic substrate 1 or the like.

[0047] Optionally, the metal plating layer 2 is a gold plating layer.

[0048] It should be pointed out that in this embodiment, there is no specific limitation on the preset position, which depends on the position of the aluminum bowl 4 on the substrate 1 .

[0049] Furthermore, the eutectic alloy layer 3 is not specifically limited in the present application and can be set at will. Optionally, the eutectic alloy layer 3 is a gold-tin alloy layer, and of course other eutectic alloy layers 3 can also be used, such as a lead-tin alloy layer, a copper-silver alloy layer, etc. Preferably, the flatness Ra of the eutectic alloy layer 3 is less than 0.3, so as to increase the connection firmness between the substrate 1 and the aluminum bowl 4.

[0050] Please refer to the structural diagram of the aluminum bowl cup 4 and the bottom diagram of the aluminum bowl cup 4 respectively. Figure 2 and Figure 3 , please refer to the schematic diagram of the structure when the UV LED chip 5 is inverted Figure 4 .

[0051] Preferably, the aluminum bowl cup 4 is an aluminum bowl cup 4 with a polished inner wall, which can further increase the reflection of the aluminum bowl cup 4 to the ultraviolet light and improve the utilization rate of the ultraviolet light.

[0052] It should be noted that in the present application, the UV LED chip 5 is flipped on the upper surface of the substrate 1, and the electrode of the UV LED chip 5 is a eutectic alloy layer, such as a gold-tin alloy layer, and the electrode of the UV LED chip 5 is eutectic welded to the substrate 1, that is, the substrate 1 is eutectically connected to the UV LED chip 5.

[0053] It should be noted that the proportion of each metal in the eutectic alloy layer 3 between the substrate 1 and the aluminum bowl 4 should be different from the proportion of each metal in the eutectic alloy layer (electrode) of the UV LED chip 5, so as to ensure that the temperature of the eutectic welding between the UV LED chip 5 and the substrate 1 is lower than the eutectic welding temperature between the substrate 1 and the aluminum bowl 4, that is, to avoid the UV LED chip 5 from falling off between the substrate 1 and the aluminum bowl 4 during the eutectic welding between the substrate 1. Taking the gold-tin alloy layer as an example, the proportion of gold and tin is described. In the eutectic alloy layer 3 between the substrate 1 and the aluminum bowl 4, gold accounts for 80%. Tin accounts for 20%, and the eutectic point is 280°C. In the electrode of the UV LED chip 5, gold accounts for 10%, tin accounts for 90%, and the eutectic point is 217°C.

[0054] Optionally, in one embodiment of the present application, the cover 6 is a quartz glass cover 6. However, the present application does not specifically limit this, and in other embodiments of the present application, the cover 6 may also be a soda-lime glass cover 6, a borosilicate glass cover 6, and the like.

[0055] It is understandable that an adhesive layer 7 (eg, solder paste) or a eutectic connection layer 7 is also provided at the connection between the cover 6 and the aluminum bowl 4 to achieve the connection between the cover 6 and the aluminum bowl 4 .

[0056] The UV LED chip 5 is not specifically limited in the present application and depends on the situation. For example, when the UV LED device is used to kill viruses, the UV LED chip 5 is a UV C LED chip. When the UV LED device is used to kill bacteria, the UV LED chip 5 is a UV A LED chip.

[0057] The important function of UV LED devices is to kill viruses and bacteria. During the process of killing viruses and bacteria, the closer the distance between the light emitted by the UV LED device and the viruses and bacteria, the better the killing and sterilization effect. In this application, the aluminum bowl 4 is located inside the UV LED device, which can effectively shorten the distance between the UV LED device and bacteria and viruses, and enhance the killing and sterilization effect.

[0058] The UV LED device in the present application includes a substrate 1 with a metal coating 2 on the surface, a eutectic alloy layer 3, an aluminum bowl cup 4, a UVLED chip 5 and a cover 6. The bowl cup is an aluminum bowl cup 4. The aluminum bowl cup 4 has a high reflectivity, which can reduce the absorption of ultraviolet light, thereby increasing the utilization rate of ultraviolet light by the UV LED device. The aluminum bowl cup 4 and the substrate 1 are connected by the eutectic alloy layer 3, which can effectively reduce the void rate of the aluminum bowl cup 4 and the substrate 1. In addition, the aluminum bowl cup 4 is directly connected to the substrate 1 through the eutectic alloy layer 3, which greatly improves the production efficiency and has high production capacity.

[0059] This application also provides a UV LED device manufacturing method, please refer to Figure 5 , the method comprising:

[0060] Step S101: obtaining a substrate with a metal coating on its surface.

[0061] Specifically, the method of obtaining a substrate having a metal coating on the surface includes:

[0062] Step S1011: preparing the substrate by using a DPC process;

[0063] Step S1012: plating a metal coating on the upper surface of the substrate.

[0064] The DPC (Direct Plate Copper) process is well known to those skilled in the art and will not be described in detail herein. The metal plating layer is a gold plating layer.

[0065] Step S102: forming a eutectic alloy layer in the area where the aluminum bowl is connected to the substrate.

[0066] Specifically, a eutectic alloy layer is evaporated in the area where the aluminum bowl is connected to the substrate.

[0067] Optionally, when the eutectic alloy layer is a gold-tin alloy layer, gold accounts for 80%, tin accounts for 20%, and the eutectic point is 280°C.

[0068] Aluminum bowls and cups can be obtained by mold stamping, which is fast.

[0069] Preferably, the inner wall of the aluminum bowl is polished to further increase the reflection of ultraviolet light by the aluminum bowl and improve the utilization rate of ultraviolet light.

[0070] Step S103: eutectic welding the substrate and the aluminum cup at a first temperature through the eutectic alloy layer.

[0071] Optionally, the aluminum bowl of the array and the substrate of the array may be eutectic welded simultaneously to increase production efficiency.

[0072] When the gold content in the gold-tin alloy layer is 80% and the tin content is 20%, the soldering temperature is 310°C.

[0073] Step S104: eutectic soldering the UV LED chip on the upper surface of the substrate at a second temperature, and the UV LED chip is located in the aluminum bowl region, and the second temperature is lower than the first temperature.

[0074] The purpose of the second temperature being lower than the first temperature is to prevent the substrate from falling off from the aluminum bowl during eutectic welding of the UV LED chip and the substrate. The second temperature is lower than the first temperature by adjusting the proportion of each metal in the eutectic alloy layer between the substrate and the aluminum bowl and the proportion of each metal in the eutectic alloy layer (electrode) of the UV LED chip.

[0075] The UV LED chip is flipped on the upper surface of the substrate, and the electrode of the UV LED chip is a eutectic alloy layer, and the electrode of the UV LED chip is eutectic soldered with the substrate. When the electrode of the UV LED chip is a gold-tin alloy layer with 10% gold and 90% tin, the eutectic point is 217°C.

[0076] Step S105: Connect the cover to the surface of the aluminum bowl facing away from the substrate.

[0077] Optionally, the cover is connected to the surface of the aluminum bowl facing away from the substrate by using an adhesive method or a eutectic welding method.

[0078] When the gluing method is used, an adhesive layer, such as solder paste, is made at the connection between the cover and the aluminum cup to connect the cover and the aluminum cup; when the eutectic welding method is used, a eutectic alloy layer is made at the connection between the cover and the aluminum cup to connect the cover and the aluminum cup. The gluing method and the eutectic welding method are well known to those skilled in the art and will not be described in detail here.

[0079] Generally, after the cap is connected to the aluminum bowl, the UV LED device needs to be tested to detect the quality of the UV LED device.

[0080] Optionally, after eutectic welding the substrate and the aluminum cup through the eutectic alloy layer, the method further includes:

[0081] The void ratios of the aluminum bowl and the substrate are detected.

[0082] Specifically, the void ratio is detected by X-rays. The specific detection process is well known to those skilled in the art and will not be described in detail here.

[0083] The UV LED device obtained by the UV LED device manufacturing method in the present application includes a substrate with a metal coating on the surface, a eutectic alloy layer, an aluminum bowl, a UV LED chip and a cover. The bowl is an aluminum bowl. The aluminum bowl has a high reflectivity and can reduce the absorption of ultraviolet light, thereby increasing the utilization rate of ultraviolet light by the UV LED device. The aluminum bowl is connected to the substrate by the eutectic alloy layer, which can effectively reduce the void rate of the aluminum bowl and the substrate. In addition, the aluminum bowl is directly connected to the substrate through the eutectic alloy layer, which greatly improves the manufacturing efficiency and has high production capacity.

[0084] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0085] The UV LED device and its manufacturing method provided by the present application are introduced in detail above. The principle and implementation method of the present application are explained in this article using specific examples. The description of the above embodiments is only used to help understand the method and its core idea of ​​the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A UV LED device, characterized in that: include: A substrate with a metal coating on the surface; the substrate is an aluminum nitride ceramic substrate, and the metal coating is a gold coating; A eutectic alloy layer located at a preset position on the upper surface of the substrate; the eutectic alloy layer is a gold-tin alloy layer, and the flatness of the eutectic alloy layer Ra is less than 0.3; An aluminum bowl connected to the substrate via the eutectic alloy layer; A UV LED chip located in the aluminum bowl region and eutectically connected to the upper surface of the substrate; Cover; the cover is a quartz glass cover; The UV LED chip is flipped on the upper surface of the substrate, and the electrode of the UV LED chip is a eutectic alloy layer, which is a gold-tin alloy layer; the proportion of each metal in the eutectic alloy layer between the substrate and the aluminum bowl is different from the proportion of each metal in the eutectic alloy layer of the UV LED chip, wherein, in the eutectic alloy layer between the substrate and the aluminum bowl, gold accounts for 80%, tin accounts for 20%, and the eutectic point is 280°C; in the electrode of the UV LED chip, gold accounts for 10%, tin accounts for 90%, and the eutectic point is 217°C.

2. The UV LED device according to claim 1, characterized in that The UV LED chip is a UV C LED chip.

3. A method for manufacturing a UV LED device, characterized in that: include: Obtaining a substrate with a metal coating distributed on the surface; The substrate is an aluminum nitride ceramic substrate, and the metal coating is a gold coating; A eutectic alloy layer is formed in the area where the aluminum bowl and the substrate are connected; the eutectic alloy layer is a gold-tin alloy layer, and the flatness Ra of the eutectic alloy layer is less than 0.3; Performing eutectic welding on the substrate and the aluminum cup through the eutectic alloy layer at a first temperature; Eutectic soldering a UV LED chip on the upper surface of the substrate at a second temperature, wherein the UV LED chip is located in the aluminum bowl region, and the second temperature is lower than the first temperature; Connecting a cover to the surface of the aluminum bowl away from the substrate; the cover is a quartz glass cover; The UV LED chip is flipped on the upper surface of the substrate, and the electrode of the UV LED chip is a eutectic alloy layer, which is a gold-tin alloy layer; the proportion of each metal in the eutectic alloy layer between the substrate and the aluminum bowl is different from the proportion of each metal in the eutectic alloy layer of the UV LED chip, wherein, in the eutectic alloy layer between the substrate and the aluminum bowl, gold accounts for 80%, tin accounts for 20%, and the eutectic point is 280°C; in the electrode of the UV LED chip, gold accounts for 10%, tin accounts for 90%, and the eutectic point is 217°C.

4. The method for manufacturing a UV LED device according to claim 3, wherein: The step of connecting the cover to the surface of the aluminum bowl facing away from the substrate comprises: The cover is connected to the surface of the aluminum bowl facing away from the substrate by using an adhesive method or a eutectic welding method.

5. The method for manufacturing a UV LED device according to claim 3, wherein: After eutectic welding the substrate and the aluminum cup through the eutectic alloy layer, the method further includes: The void ratios of the aluminum bowl and the substrate are detected.

6. The method for manufacturing a UV LED device according to claim 3, wherein: The method of obtaining a substrate having a metal coating distributed on the surface comprises: The substrate is prepared by using a DPC process; A metal coating is plated on the upper surface of the substrate.

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