LED packaging structure

Abstract

The present invention provides an LED packaging structure, including a substrate, a transparent cover and a dam connected to the substrate, the dam, the transparent cover and the substrate together form an installation area; the dam includes an outer retaining wall and an inner retaining wall, a groove is provided between the outer retaining wall and the inner retaining wall, the LED packaging structure also includes a seal arranged in the groove, the transparent cover covers the inner retaining wall and the installation area, and the transparent cover is inserted into the groove; the LED packaging structure also includes a protective member arranged at the edge of the transparent cover, the protective member has a sealing portion for sealing the gap between the transparent cover and the outer retaining wall, and a pressing portion connected to the sealing portion and capable of abutting against the upper end of the transparent cover. The LED packaging structure provided by the present invention, under the shielding of the inner retaining wall, the outer retaining wall and the sealing portion, the seal can avoid UV irradiation, has the advantages of both semi-inorganic packaging and full inorganic packaging, overcomes the limitations of both, and has better air tightness and stability.

Description

Technical Field

[0001] The invention belongs to the technical field of LED packaging, and in particular relates to an LED packaging structure. Background Art

[0002] Ultraviolet light-emitting diodes (UV-LEDs) are energy-saving, environmentally friendly, long-life, and small in size. In UV-LED packaging, the airtightness of the product is the main factor affecting the product life. For products with poor airtightness, water vapor from the environment will enter the product during use, thereby reducing the service life of the UV-LED product and even causing the UV-LED device to fail.

[0003] The packaging of UV-LED usually includes chips, ceramic substrates and glass lenses. Among them, the tightness of the combination of glass lenses and ceramic substrates is the key to ensuring the airtightness of the product. At this stage, the mainstream technology for combining glass lenses and ceramic substrates on the market is to use organic glue to bond the glass lens to the ceramic substrate, commonly known as a semi-inorganic packaging process, or to inlay metal around the glass lens and weld the metal to the ceramic substrate, commonly known as a full inorganic packaging process. In the semi-inorganic packaging process, the glue has fluidity and has a good effect on filling the contact gap between the ceramic substrate and the glass lens, so the airtightness is better, but the organic glue will fail under UV irradiation or long-term heating, causing the glass lens to fall off. In the inorganic packaging process, because organic glue is not used, and the connection method through welding is very strong, there will be no problem of glass lens falling off, but the welding of the metal-inlaid glass lens and the substrate will produce pores or cracks, and there will also be a contact gap at the contact between the glass lens and the ceramic substrate, and the airtightness cannot be effectively guaranteed. The structure of the ceramic substrate in the prior art either makes it difficult to combine the advantages of the above two processes at the same time, or when combining the advantages of the two processes, there are limitations on the selection of gap filling materials. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide an LED packaging structure which has the advantages of both semi-inorganic packaging and full inorganic packaging, overcomes the limitations of both, and has better airtightness and stability.

[0005] The technical solution of the present invention is: an LED packaging structure, comprising a substrate, a transparent cover and a dam connected to the substrate, the dam, the transparent cover and the substrate together form an installation area; the dam comprises an outer retaining wall and an inner retaining wall, a groove is provided between the outer retaining wall and the inner retaining wall, the LED packaging structure also comprises a sealing member arranged in the groove, the transparent cover covers the inner retaining wall and the installation area, and the transparent cover is inserted into the groove; the LED packaging structure also comprises a protective member arranged at the edge of the transparent cover, the protective member comprises a sealing portion for sealing the gap between the transparent cover and the outer retaining wall, and a pressing portion connected to the sealing portion and capable of abutting against the upper end of the transparent cover.

[0006] As a further improvement of the present technical solution, a plurality of protective members are provided, and the plurality of protective members partially cover the upper surface of the transparent cover, and the distance between the end faces of the two pressing portions opposite to each other on the upper surface of the transparent cover is not greater than the distance between the two side walls of the inner retaining wall opposite to each other and facing the groove.

[0007] As a further improvement of the present technical solution, the sealing member comprises an inner sealing portion for abutting against the inner baffle wall and the inner side of the transparent cover, an outer sealing portion for abutting against the outer baffle wall and the outer side of the transparent cover, and a transverse sealing portion for abutting against the bottom of the groove and the bottom of the transparent cover; one end of the transverse sealing portion is connected to the outer sealing portion, and the other end of the transverse sealing portion is connected to the inner sealing portion, and the inner sealing portion, the outer sealing portion and the transverse sealing portion enclose a mounting groove for mounting the transparent cover.

[0008] As a further improvement of the present technical solution, the transparent cover includes a face cover portion and a longitudinal portion connected to the outer peripheral side of the face cover portion; one side surface of the inner sealing portion is in contact with the inner side surface of the longitudinal portion, the other side surface of the inner sealing portion is in contact with the side surface of the inner retaining wall, and the bottom of the longitudinal portion is in contact with the transverse sealing portion.

[0009] As a further improvement of the present technical solution, the protective member further includes a fixing portion connected to the blocking portion and used for fixing the fixing portion with the outer retaining wall, and the fixing portion partially overlaps with the outer retaining wall.

[0010] As a further improvement of the technical solution, the fixing portion partially overlaps with the upper end surface of the outer retaining wall or the side surface facing the groove.

[0011] As a further improvement of the technical solution, the height of the inner retaining wall is a first height, the height of the outer retaining wall is a second height, and the first height is greater than the second height;

[0012] The fixing portion is connected to one end of the blocking portion, and the pressing portion is connected to the other end of the blocking portion.

[0013] As a further improvement of the technical solution, the height of the inner retaining wall is a first height, the height of the outer retaining wall is a second height, and the first height is smaller than the second height; the outer side of the blocking portion is in contact with the outer retaining wall.

[0014] As a further improvement of the technical solution, the fixing portion is connected to the blocking portion and the pressing portion respectively.

[0015] As a further improvement of the technical solution, the sealing member is made of silicone or epoxy resin.

[0016] The LED packaging structure provided by the present invention comprises the following steps: a dam having an outer retaining wall and an inner retaining wall is arranged on the substrate, a groove is provided between the outer retaining wall and the inner retaining wall, a sealing member is arranged in the groove, the transparent cover covers the inner retaining wall and the installation area and the transparent cover is inserted into the groove, the protective member is arranged at the edge of the transparent cover, and the blocking portion of the protective member blocks between the transparent cover and the outer retaining wall, and the pressing portion abuts against the upper end of the transparent cover, so that the transparent cover and the substrate are tightly combined, and under the shielding of the inner retaining wall and the outer retaining wall and the blocking of the blocking portion, the sealing member can avoid UV irradiation and has good air tightness, realizing a packaging process combining semi-inorganic packaging with full inorganic packaging, solving the problem that the transparent cover falls off due to the failure of glue under long-term irradiation of UV light in the semi-inorganic packaging, and having the advantages of both semi-inorganic packaging and full inorganic packaging, ensuring the air tightness of UV-LED products, and being conducive to improving the service life of UV-LED devices and having better stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 is a structural schematic diagram of an LED packaging structure provided by an embodiment of the present invention;

[0019] Figure 1-a is another structural schematic diagram of an LED packaging structure provided by an embodiment of the present invention;

[0020] Figure 1-b is another structural schematic diagram of an LED packaging structure provided by an embodiment of the present invention;

[0021] Figure 1-c is another structural schematic diagram of an LED packaging structure provided by an embodiment of the present invention;

[0022] Figure 1-d is another structural schematic diagram of an LED packaging structure provided by an embodiment of the present invention;

[0023] Figure 1-e is another structural schematic diagram of an LED packaging structure provided by an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of a dam in an LED packaging structure provided by an embodiment of the present invention;

[0025] Figure 3 is another structural schematic diagram of an LED packaging structure provided by an embodiment of the present invention;

[0026] Figure 4 It is a flow chart of a packaging method for an LED packaging structure provided by an embodiment of the present invention.

[0027] Numbers in the figure:

[0028] 1-substrate, 11-internal circuit, 12-internal conductive hole, 13-bottom circuit, 14-heat dissipation part, 2-transparent cover, 21-surface cover part, 22-longitudinal part, 3-dam, 31-inner retaining wall, 32-outer retaining wall, 33-groove, 4-protective part, 41-sealing part, 42-fixing part, 43-pressing part, 5-sealing part, 51-inner sealing part, 52-outer sealing part, 53-transverse sealing part, 6-LED chip, 7-installation area. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0030] It should be noted that the terms “setting” and “connection” should be understood in a broad sense. For example, it can be directly setting or connecting, or it can be indirectly setting or connecting through a central component or a central structure.

[0031] In addition, in the embodiments of the present invention, if there are terms indicating orientation or positional relationships such as "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., they are based on the orientation or positional relationships or conventional placement states or usage states shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the structure, feature, device or element referred to must have a specific orientation or positional relationship, nor must it be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0032] The various specific technical features and embodiments described in the specific implementation methods can be combined in any suitable manner unless there is any contradiction. For example, different implementation methods can be formed by combining different specific technical features / embodiments. In order to avoid unnecessary repetition, the various possible combinations of the specific technical features / embodiments in the present invention will not be described separately.

[0033] like Figure 1 and Figure 3 As shown, an LED packaging structure provided by an embodiment of the present invention includes a substrate 1, a transparent cover 2 and a dam 3 (such as Figure 2As shown), the dam 3 is connected to the substrate 1, specifically, the dam 3 is a copper dam, the substrate 1 is a ceramic substrate, the substrate 1 is connected with an LED chip 6 (UV-LED chip in this embodiment), and the dam 3, the transparent cover 2 and the substrate 1 together form a mounting area 7; the transparent cover 2 is a glass lens, which can be made of quartz glass or sapphire glass; the dam 3 includes an outer retaining wall 32 and an inner retaining wall 31, both of which are walls, which can be square walls or circular walls, and a groove 33 is provided between the outer retaining wall 32 and the inner retaining wall 31; the LED packaging structure The LED package structure further comprises a sealing member 5 arranged in the groove 33, the transparent cover 2 covers the inner baffle 31 and the installation area 7, and the transparent cover 2 is inserted into the groove 33 and connected with the sealing member 5; the LED package structure further comprises a protective member 4, the protective member 4 is arranged at the edge of the transparent cover 2; the protective member 4 has a blocking portion 41 and a pressing portion 43, the blocking portion 41 blocks between the transparent cover 2 and the outer baffle 32, the pressing portion 43 can be pressed against the upper end of the transparent cover 2, and the pressing portion 43 is connected to the blocking portion 41; in specific applications, the protective member 4 is a metal protective member, all of which are The protective member 4 is made of metal. In this embodiment, the protective member 4 can be welded to the substrate 1 (laser welding is used in this embodiment). The welding connection is very strong and can effectively prevent the glass lens from falling off. In addition, since the metal protective member arranged on the glass lens is not directly welded to the substrate 1, but welded to the outer retaining wall 32 of the copper dam, the blocking portion 41 is blocked between the transparent cover 2 and the outer retaining wall 32, which can prevent the sealing member 5 from being irradiated by UV. The glass lens and the ceramic substrate are tightly combined to enhance the airtightness. If there is no crack in the welding, the airtightness is better. If there is a crack, it can also be ensured by the sealing member 5 arranged in the groove 33. Airtightness, airtightness is doubly guaranteed, it has the advantages of inorganic packaging technology and overcomes its limitations; and, even if cracks appear in the glass lens during welding or subsequent use, it can still meet the use requirements; the setting of the seal 5 has a good filling effect on the contact gap between the ceramic substrate and the glass lens, so that the LED packaging structure has good airtightness, and because the seal 5 is shielded by the inner baffle wall 31 and the outer baffle wall 32, and is blocked by the blocking part 41 and the pressing part 43, UV radiation can be avoided, thereby effectively preventing the glass lens from falling off, taking its advantages while overcoming the limitations of the semi-inorganic packaging process.An LED packaging structure provided by the embodiment of the present invention enables the transparent cover 2 (a glass lens in the present embodiment) and the substrate 1 (a ceramic substrate in the present embodiment) to be tightly combined with each other with good airtightness, realizes a packaging process combining semi-inorganic packaging with full inorganic packaging, solves the problem of the transparent cover 2 falling off due to the failure of glue under long-term irradiation of UV light in the semi-inorganic packaging, and has the advantages of both semi-inorganic packaging and full inorganic packaging, overcomes the limitations of both, ensures the airtightness of UV-LED products, is conducive to improving the service life of UV-LED devices, has better stability, and has high practical application value.

[0034] In a specific application, the substrate 1 is a ceramic substrate, which includes a ceramic layer, an internal circuit 11, an internal conductive hole 12 and a bottom circuit 13. The copper dam is arranged on one side of the ceramic layer, and the internal circuit is located on the inner side of the inner retaining wall 31; wherein, the internal circuit and the bottom circuit are connected by setting the internal conductive hole 12 in the ceramic layer, and the bottom circuit, the internal circuit and the copper dam are combined with the ceramic layer through the DPC process (Direct Plating copper, direct copper plating technology) on the ceramic layer, and the UV-LED chip is located on the inner side of the inner retaining wall 31 and connected to the internal circuit 11. In other embodiments, the ceramic substrate further includes a heat dissipation portion 14 located at the bottom.

[0035] In some examples of this embodiment, the protective member 4 is provided in plurality, and the plurality of protective members 4 partially cover the upper surface of the transparent cover 2. The distance between the end faces of the two opposing pressing portions 43 located on the upper surface of the transparent cover 2 is not greater than the distance between the two opposing side walls of the inner retaining wall 31 facing the groove 33, that is, the hollow width of the upper surface of the metal inlay block located on the upper surface of the glass lens is not greater than the distance between the two side walls of the inner retaining wall 31 facing the groove 33 (that is, the two inner side walls of the inner retaining wall 31). In some other examples of this embodiment, the protective member 4 can be provided in four pieces, which are respectively provided at four right angles of the transparent cover 2 or at the middle positions of the four side edges of the transparent cover 2, and partially cover the upper surface of the transparent cover 2. In other embodiments, the protective member 4 can also be provided in only two pieces, and they are relatively symmetrically provided on the side edges of the transparent cover 2. In other embodiments, the number of the protective members 4 can also be other values, such as three, six, etc. The seal 5 is hidden between the transparent cover 2 (glass lens) of the substrate 1 and the protective member 4 (inlaid metal block). The side portion of the light emitted from the UV chip is blocked by the inner retaining wall 31 of the dam 3 (copper dam). Because the hollow width of the upper surface of the metal inlaid block located on the upper surface of the glass lens is not greater than the distance between the side walls of the groove 33 on both sides of the inner retaining wall 31, the external UV light is reflected back and blocked by the glass lens inlaid metal block and the outer retaining wall of the copper dam, which can ensure that the seal is not affected by UV light, has better reliability, and ensures the airtightness of the UV-LED product.

[0036] In this embodiment, Figure 1 and 3 As shown, the sealing member 5 comprises an inner sealing portion 51, an outer sealing portion 52 and a transverse sealing portion 53, the transparent cover 2 comprises a surface cover portion 21 and a longitudinal portion 22, the longitudinal portion 22 being connected to the outer peripheral side of the surface cover portion 21, the inner sealing portion 51 is respectively in contact with the inner baffle wall 31 and the inner side of the transparent cover 2, the outer sealing portion 52 is respectively in contact with the outer baffle wall 32 and the outer side of the longitudinal portion 22 of the transparent cover 2, the transverse sealing portion 53 is respectively in contact with the bottom of the groove 33 and the bottom of the transparent cover 2, one end of the transverse sealing portion 53 is connected to the outer sealing portion 52, and the other end of the transverse sealing portion 53 is connected to the inner sealing portion 51, the sealing member may have an installation groove, the inner sealing portion 51, the outer sealing portion 52 and the transverse sealing portion 53 enclose a mounting groove for mounting the transparent cover 2, that is, the two sides of the mounting groove are the inner sealing portion 51 and the outer sealing portion 52, respectively, and the bottom of the mounting groove is the transverse sealing portion 53. The longitudinal portion 22 and the inner wall of the mounting groove can be closely connected to eliminate gaps and achieve good air tightness. Figure 1-a As shown, the inner sealing portion 51 is not flush with the upper end of the inner retaining wall 31, and the outer sealing portion 52 is not flush with the upper end of the outer retaining wall 32, that is, a certain gap is left at the upper ends of the inner sealing portion 51 and the outer sealing portion 52. The gap is set and reserved according to the characteristics of the material to give the seal 5 enough thermal expansion space. In other examples, such as Figure 1-b As shown, the width of the seal 5 is consistent with the width of the longitudinal portion 22 of the transparent cover 2, that is, the seal 5 has only one part, the transverse sealing portion 53, so that the packaging structure is compact and has strong stability. In other examples, such as Figure 1-c , Figure 1-d As shown, at least one side of the longitudinal portion 22 of the transparent cover 3 is in contact with the retaining wall of the dam 3. When installing the transparent cover 2, the point where the longitudinal portion 22 is in contact with the retaining wall can be used as a positioning point to facilitate installation. Figure 1-c The seal shown has only an outer seal portion 52 and a transverse seal portion 53; Figure 1-d The seal shown has only an inner seal portion 51 and a transverse seal portion 53 .

[0037] In specific applications, the seal 5 can be prefabricated by a mold and installed in the groove 33. Then, when the transparent cover 2 is inserted into the groove 33, it will abut against the seal 5. In other examples, the seal 5 can also directly apply a certain amount of fluid glue, that is, liquid glue, to the bottom of the groove 33, and then the transparent cover 2 is inserted into the groove 33, and then baked and cured. When the seal 5 is formed by this method, the inner retaining wall 31 and the outer retaining wall 32 can effectively prevent the glue from overflowing into the cup body of the substrate 1 or outside the substrate 1, and prevent the overflowed glue from affecting the parameters and air tightness of the product. Specifically, the seal 5 can be made of silicone, epoxy resin or other packaging glue. In the traditional packaging process, the glue on the surface of the copper dam and the glue that overflows into the cup of the substrate will turn yellow and become ineffective after being exposed to UV light for a long time, affecting the product parameters and airtightness, and only non-fluid materials can be used to fill the gap. The LED packaging structure provided in the embodiment of the present invention can achieve gap filling using either fluid or non-fluid (i.e., preformed using a mold) materials, thus overcoming the limitations of the traditional packaging process in the selection of filling materials, having better applicability, and reducing the packaging cost.

[0038] In some examples of this embodiment, the protective member 4 further includes a fixing portion 42, and the fixing portion 42 is connected to the blocking portion 41, and the fixing portion 42 is fixedly connected to the outer retaining wall 32. In this embodiment, the fixing portion 42 is integrally connected to the blocking portion 41, and the inner side of the blocking portion 41 is in contact with the longitudinal portion 22, and the inner wall of the pressing portion 43 is in contact with the upper end of the surface cover portion 21, that is, both inner side surfaces of the protective member 4 can be in contact with the transparent cover 2, and the protective effect is better. In other examples, the fixing portion 42 partially overlaps with the outer retaining wall 32, and the fixing portion 42 partially overlaps with the upper end surface of the outer retaining wall 32, so that the protective member 4 has a support in the vertical direction, which is convenient for welding and is firmly welded. In other examples, such as Figure 1-e As shown, the fixing portion 42 and the side of the outer retaining wall 32 facing the groove 33 partially overlap, and the end face of the fixing portion 42 abuts against the sealing member 5, that is, the sealing member 5 supports the protective member 4, making welding convenient. At the same time, since the sealing member 5 may be slightly deformed due to compression, the sealing member 5 may be fully compressed when the protective member 4 is installed, so as to reduce the installation gap as much as possible and enhance the airtightness of the packaging structure. In other embodiments, there may also be a gap between the end face of the fixing portion 42 and the sealing member 5, so that the pressing portion 43 can fully abut against the upper surface of the transparent cover 2 to prevent the transparent cover 2 from loosening.

[0039] In the embodiment of the present invention, the height of the inner retaining wall 31 is not equal to the height of the outer retaining wall 32. The groove 33 between the inner retaining wall 31 and the outer retaining wall 32 is described in detail in the following two embodiments.

[0040] Example 1

[0041] The height of the inner retaining wall 31 is the first height, and the height of the outer retaining wall 32 is the second height. The first height is greater than the second height, that is, the inner retaining wall 31 is higher than the outer retaining wall 32. As shown in Figure 1 and Figure 2 shown, there is a groove 33 between the inner retaining wall 31 and the outer retaining wall 32. The combined cross-section of the inner retaining wall 31, the bottom of the groove 33, and the outer retaining wall is in an "L" shape, or a sealing member 5 is installed, and the cross-section of the sealing member 5 can be in an "L" shape; the fixing portion 42 is connected to one end of the blocking portion 41, and the pressing portion 43 is connected to the other end of the blocking portion 41. The cross-section of the protective member 4 is in a Z shape, and the fixing portion 42 can be in contact with the upper end of the outer retaining wall 32 and the upper end of the outer sealing portion 52. In this embodiment, the upper ends of the outer retaining wall 32 and the outer sealing portion 52 are flush, and the top of the outer retaining wall 32 and the outer sealing portion 52 are sealed by a metal protective member, with good airtightness.

[0042] Example 2

[0043] The height of the inner retaining wall 31 is the first height, and the height of the outer retaining wall 32 is the second height. As an alternative to the above embodiment, in this embodiment, the first height is less than the second height. As shown in Figure 3 shown, that is, the inner retaining wall 31 is lower than the outer retaining wall 32, and a groove 33 is formed between the inner retaining wall 31 and the outer retaining wall 32; the outside of the blocking portion 41 is in contact with the outer retaining wall 32, the blocking portion 41 is connected to the outer sealing portion 52, the sum of the height of the blocking portion 41 and the height of the outer sealing portion 52 is equal to the height of the outer retaining wall 32, the bottom wall of the fixing portion 42 can be in contact with the upper end of the outer retaining wall 32, the fixing portion 42 is respectively connected to the blocking portion 41 and the pressing portion 43, and the cross-section of the protective member 4 is in a T shape, with excellent airtightness.

[0044] The embodiment of the present invention also provides a packaging method for an LED packaging structure. The packaging method is used to package the above-mentioned LED packaging structure. Please refer to Figure 4 shown, and includes the following steps:

[0045] S401: Prepare a substrate 1 with a dam 3 such that the dam 3 is provided with an outer retaining wall 32 and an inner retaining wall 31, and there is a groove 33 between the outer retaining wall 32 and the inner retaining wall 31.

[0046] Specifically, the substrate 1 is a ceramic substrate, the dam 3 is a copper dam, and the DPC (direct copper plating technology-Direct Plating Copper) process is used to form the internal circuit 11, the external circuit, the internal via 12 and the dam 3 on the ceramic substrate. The specific process route is laser hole conversion, vacuum plating, die pressing, circuit exposure, circuit development, electroplating hole filling, grinding, sandblasting, die pressing, copper dam production exposure, copper dam development, electroplating copper dam, grinding, film stripping, copper and titanium stripping, electrical testing, surface treatment and other processes. In other embodiments, a heat dissipation portion 14 for heat dissipation can also be formed at the bottom of the substrate.

[0047] It can be understood that the dam 3 manufactured through the above steps is formed with an outer retaining wall 32 and an inner retaining wall 31, so that a groove 33 is formed between the outer retaining wall 32 and the inner retaining wall 31. Based on the above introduction, it can be known that the height of the inner retaining wall 31 is defined as a first height, and the height of the outer retaining wall 32 is defined as a second height. In some examples of this embodiment, the first height is greater than the second height, and in other examples, the first height is less than the second height.

[0048] Specifically, the packaging method also includes a chip solidification step, where flux is applied to the internal circuit of the substrate 1 (ceramic substrate), and the LED chip 6 is soldered to the area with the flux; wherein the soldering pad of the LED chip 6 is a gold-tin alloy; the role of the flux is to act as a eutectic medium, so that the LED chip 6 and the substrate 1 are tightly combined during eutectic formation, and the ceramic substrate circuit needs to be nickel-gold plated, with a thickness requirement of nickel>3um and gold>0.05um; the packaging method also includes a chip eutectic step, where the substrate 1 (ceramic substrate) with the LED chip 6 fixed thereon is passed through a eutectic furnace, so that the LED chip 6 and the ceramic substrate are firmly combined, wherein the eutectic furnace temperature has at least one temperature zone between 300°C-340°C and the eutectic process requires nitrogen protection.

[0049] S402: placing the sealing member 5 in the groove 33;

[0050] Specifically, the seal 5 can be preformed by a mold, and then the seal 5 can be installed in the groove 33. In some examples, a certain amount of fluid thermosetting glue can be directly applied to the bottom of the groove 33, and the seal 5 can be formed by baking and curing. The fluid glue, that is, liquid glue, is used to make the seal 5, which needs to be baked and cured later. Under the action of the inner retaining wall 31 and the outer retaining wall 32, the glue can be effectively prevented from overflowing into the cup body of the substrate 1 or outside the substrate 1, and the overflowed glue can be prevented from affecting the parameters and air tightness of the product. The gap between the transparent cover 2 and the dam 3 can be filled with fluid or non-fluid (that is, preformed by a mold) materials, which overcomes the limitations of the selection of filling materials in traditional packaging processes, has better applicability, and can reduce packaging costs.

[0051] S403: Cover the inner baffle wall 31 and the installation area 7 with the transparent cover 2, insert it into the groove 33 and abut against the sealing member 5;

[0052] Based on the above introduction, it can be known that in one embodiment, the transparent cover 2 includes a surface cover portion 21 and a longitudinal portion 22 connected to the outer peripheral side of the surface cover portion 21. Through the above steps, the seal 5 fills the gap between the transparent cover 2 and the dam 3, thereby improving the airtightness of the packaging structure.

[0053] S404: disposing the protective member 4 at the edge of the transparent cover 2 , and making the blocking portion 41 of the protective member 4 block between the transparent cover 2 and the outer baffle wall 32 , making the pressing portion 43 abut against the upper end of the transparent cover 2 , and fixing the protective member 4 to the outer baffle wall 32 .

[0054] Specifically, in one embodiment, the pressing portion 43 of the protective member 4 can be covered on the upper surface of the transparent cover 2, so that the distance between the end surfaces of the two pressing portions 43 located on the upper surface of the transparent cover 2 is not greater than the distance between the two side walls of the inner baffle 31 facing the groove 33. Through the above steps, the sealing member 5 is shielded by the inner baffle 31 and the outer baffle 32, and blocked by the blocking portion 41 and the pressing portion 43, so that the reliability of the packaging structure is better, and the airtightness of the UV-LED product is guaranteed.

[0055] Based on the above introduction, it can be known that in some examples, the protective member 4 can also be provided with a fixing portion 42, and the fixing portion 42 is fixedly connected to the outer retaining wall 32, and the transparent cover 2 (glass lens) is tightly combined with the ceramic substrate. In this embodiment, the protective member 4 is a metal protective member, and the fixing portion 42 is integrally connected to the blocking portion 41, both of which are made of metal. In this embodiment, the fixing portion 42 can be laser welded to the substrate 1, and the welding connection method is very strong, which can effectively prevent the glass lens from falling off. In some examples, the fixing portion 42 of the protective member 4 can be set on the upper end face of the outer retaining wall 32, so that the fixing portion 42 and the upper end face of the outer retaining wall 32 have a partial position overlap, so that the protective member 4 has a support in the vertical direction, which is convenient for welding and the welding is firm.

[0056] In other examples, the fixing portion 42 of the protective member 4 can be arranged in the groove 33 so that the fixing portion 42 partially overlaps with the side of the outer retaining wall 32 facing the groove 33. When the protective member 4 is installed, the sealing member 5 can be compressed. Since the sealing member 5 is compressed, it can be slightly deformed, thereby reducing the installation gap as much as possible and enhancing the air tightness of the packaging structure. In other embodiments, there can be a gap between the protective member 4 and the sealing member 5, so that when the protective member 4 is installed, the pressing portion 43 can fully abut against the upper surface of the transparent cover 2 to prevent the transparent cover from loosening.

[0057] An LED packaging structure provided by an embodiment of the present invention comprises a dam 3 having an outer retaining wall 32 and an inner retaining wall 31 arranged on the substrate 1, a groove 33 being arranged between the outer retaining wall 32 and the inner retaining wall 31, a sealing member 5 being arranged in the groove 33, the transparent cover 2 covering the inner retaining wall 31 and the mounting area 7 and the transparent cover 2 being plugged into the groove 33 and connected to the sealing member 5, the protective member 4 being arranged at the edge of the transparent cover 2, and the blocking portion 41 of the protective member 4 blocking between the transparent cover 2 and the outer retaining wall 32, and the pressing portion 43 The sealant is against the upper end of the transparent cover 2, and under the shielding of the inner baffle wall 31 and the outer baffle wall 32 and the blocking of the blocking part 41 and the pressing part 43, the sealant can avoid UV irradiation, so that the transparent cover 2 and the substrate 1 are tightly combined with each other, and the airtightness is good, realizing the packaging process combining semi-inorganic packaging with full inorganic packaging, solving the problem that the transparent cover 2 falls off due to the failure of glue under long-term irradiation of UV light in the semi-inorganic packaging, and having the advantages of both semi-inorganic packaging and full inorganic packaging, ensuring the airtightness of UV-LED products, which is beneficial to improving the service life of UV-LED devices and having better stability.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent substitution or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An LED packaging structure, characterized in that: The LED packaging structure comprises a substrate, a transparent cover and a dam connected to the substrate, wherein the dam, the transparent cover and the substrate together form an installation area; the dam comprises an outer retaining wall and an inner retaining wall, wherein a groove is provided between the outer retaining wall and the inner retaining wall, and the LED packaging structure further comprises a sealing member arranged in the groove, the transparent cover covers the inner retaining wall and the installation area, and the transparent cover is inserted into the groove and connected to the sealing member; the LED packaging structure further comprises a protective member arranged at the edge of the transparent cover, wherein the protective member comprises a sealing portion for sealing the gap between the transparent cover and the outer retaining wall, and a pressing portion connected to the sealing portion and capable of pressing against the upper end of the transparent cover, so that the sealing member is protected from UV radiation under the shielding of the inner retaining wall and the outer retaining wall, and under the sealing of the sealing portion and the pressing portion.

2. The LED packaging structure according to claim 1, characterized in that: There are multiple protective members, which partially cover the upper surface of the transparent cover, and the distance between the end faces of the two opposing pressing parts on the upper surface of the transparent cover is no greater than the distance between the two opposite side walls of the inner retaining wall facing the groove.

3. The LED packaging structure according to claim 1, characterized in that: The sealing member comprises an inner sealing portion for contacting with the inner baffle wall and the inner side of the transparent cover, an outer sealing portion for contacting with the outer baffle wall and the outer side of the transparent cover, and a transverse sealing portion for contacting with the bottom of the groove and the bottom of the transparent cover; one end of the transverse sealing portion is connected to the outer sealing portion, and the other end of the transverse sealing portion is connected to the inner sealing portion; the inner sealing portion, the outer sealing portion and the transverse sealing portion enclose a mounting groove for mounting the transparent cover.

4. The LED packaging structure according to claim 3, characterized in that: The transparent cover includes a surface cover portion and a longitudinal portion connected to the outer peripheral side of the surface cover portion; one side surface of the inner sealing portion is in contact with the inner side surface of the longitudinal portion, the other side surface of the inner sealing portion is in contact with the side surface of the inner retaining wall, and the bottom of the longitudinal portion is in contact with the transverse sealing portion.

5. The LED packaging structure according to claim 1, characterized in that: The protective member also includes a fixing portion connected to the blocking portion and used for fixing with the outer retaining wall, and the fixing portion and the outer retaining wall are partially overlapped.

6. The LED packaging structure according to claim 5, characterized in that: The fixing portion partially overlaps with the upper end surface of the outer retaining wall or the side surface facing the groove.

7. The LED packaging structure according to claim 5, characterized in that: The height of the inner retaining wall is a first height, the height of the outer retaining wall is a second height, and the first height is greater than the second height; the fixing portion is connected to one end of the blocking portion, and the pressing portion is connected to the other end of the blocking portion.

8. The LED packaging structure according to claim 5, characterized in that: The height of the inner retaining wall is a first height, the height of the outer retaining wall is a second height, the first height is smaller than the second height; the outer side of the blocking portion is in contact with the outer retaining wall.

9. The LED packaging structure according to claim 8, characterized in that: The fixing portion is connected to the blocking portion and the pressing portion respectively.

10. The LED packaging structure according to any one of claims 1 to 9, characterized in that: The sealing element is made of silicone or epoxy resin.

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