Ultraviolet LED device and preparation method thereof

Abstract

The invention discloses an ultraviolet LED device and a preparation method thereof. The ultraviolet LED device comprises a substrate; one side of the substrate is provided with an electrode bonding pad and a heat dissipation electrode; the edge of the other side of the substrate is provided with a box dam, and the inner side of the box dam is an inclined plane on which a first reflecting material is formed; a light-emitting chip is arranged in the middle of the box dam of the substrate, and the light-emitting chip and the electrode bonding pad are correspondingly connected with each other; a second reflecting material covers between the box dams of the substrate and the surface of the substrate outside the light-emitting chip, and a filler is filled between the box dams; quartz glass is formed on the filler and the top of the dam. The light extraction effect is improved through multiple reflections.

Description

Technical Field

[0001] The present application relates to the field of ultraviolet LEDs, and in particular to an ultraviolet LED device and a method for preparing the same. Background Art

[0002] The traditional UV lamp packaging structure mainly adopts substrate dam packaging, but due to the absorption and shielding effects of the substrate dam, the optical power output of small and medium-sized lamp beads is limited.

[0003] Although the medium-sized ceramic flat-panel substrate plus fluorine resin packaging process currently available on the market can increase the light power output, most manufacturers are unable to achieve mass production, and the price is relatively high. It still cannot reach the sterilization dose per unit area required for industrial water treatment, and cannot achieve an instant sterilization effect.

[0004] Technical barriers currently encountered in the market: 1. Although the process of adding fluorine resin to small-sized ceramic flat substrates can improve the light power, the extraction of fluorine resin is difficult, and most of the domestic production cannot reach the mass production level. Due to the difficulty of the manufacturing process, the cost of a single lamp bead is high, which is unacceptable to the application end.

[0005] 2. Carbon fluorocarbons, carbon silicon compounds, and carbon fluorocarbons are filled between small-sized conventional lamp beads and quartz glass. Their refractive index is about 1.3. Light passes through the sapphire (1.76-1.77) on the surface of the light-emitting chip and the quartz lens (1.44-1.46). The light route goes from the optically dense medium to the optically sparse medium, and then to the optically dense medium. There will be partial reflection or even total reflection in the middle, which makes some light unable to be extracted. Summary of the Invention

[0006] In order to solve the problems existing in the prior art, the present invention provides a small- to medium-sized ultraviolet LED device that can reflect light emitted from the side of a light-emitting chip through a reflective material to achieve efficient extraction.

[0007] An ultraviolet LED device, comprising: substrate; An electrode pad and a heat dissipation electrode are provided on one side of the substrate; A dam is provided on the other edge of the substrate, and an inner side of the dam is an inclined surface formed with a first reflective material; A plurality of light-emitting chips are arranged on the substrate within the dam, and the light-emitting chips and the electrode pads are correspondingly interconnected; Between the dams of the substrate, the surface of the substrate outside the light emitting chip is covered with a second reflective material. Fillers are filled between the dams, and the fillers cover the chips; Quartz glass is formed on the top of the filler and the dam, and the quartz glass at the corresponding position on the top of each chip is a convex lens.

[0008] Optionally, the substrate includes an aluminum compound layer and / or copper.

[0009] Optionally, the substrate has two electrode pads with a thickness of 0.15 mm and a surface plated with metal copper, which serve as circuit connections for the light-emitting chip.

[0010] Optionally, there are 4 light-emitting chips, which cover all UVA, UVB or UVC bands and are connected in 2 series and 2 parallel modes. The welding with the aluminum nitride layer mainly includes eutectic welding and solder paste welding.

[0011] Optionally, a bidirectional Zener diode connected to the electrode pad is provided on the substrate.

[0012] Optionally, the second reflective material is Teflon material or UV high reflective material, and the reflectivity of the second reflective material is greater than the reflectivity of the first reflective material.

[0013] Optionally, the bottom of the quartz glass is square, and the upper surface is four convex lenses, and the four convex lenses correspond to the four light-emitting chips one by one, wherein the center of each light-emitting chip corresponds to the central axis of the convex lens of the integrated quartz glass.

[0014] Optionally, the bottom of the quartz glass is square, and the upper surface is a hemispherical convex lens.

[0015] Optionally, the filler material is fluorocarbon oxide.

[0016] Optionally, the first reflective material is an aluminum reflector, a silver reflector, a silicon reflector, Teflon, or magnesium fluoride.

[0017] A method for preparing an ultraviolet LED device comprises the following steps: providing a substrate; Fixing the light-emitting chip on the substrate; forming an electrode pad and a heat dissipation electrode on one side of the substrate; A dam is formed on the other edge of the substrate, and the inner side of the dam is an inclined surface; forming a first reflective material on the inner slope of the dam; A light-emitting chip is arranged in the middle of the substrate dam, and the light-emitting chip and the electrode pads are correspondingly interconnected; Between the dams of the substrate and outside the light emitting chip, the surface of the substrate is covered with a second reflective material. Filling between the dams; Quartz glass forms on top of the filler and dam.

[0018] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: The present invention utilizes multiple reflections to improve the light extraction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 1 is a schematic top view of an embodiment of a UV LED device; Figure 2 is a cross-sectional schematic diagram of an embodiment of a substrate; Figure 3 is a cross-sectional schematic diagram of an embodiment of a UV LED device; Figure 4 The front view of an embodiment of an integrated quartz glass is shown; Figure 5 FIG. 1 is a schematic cross-sectional view of an ultraviolet LED device according to another embodiment of the ultraviolet LED device; Figure 6 This is a front view schematic diagram of an embodiment of a UV LED device; Figure 7 This is a schematic diagram of a multi-string and multi-parallel circuit connection of light-emitting chips in an embodiment of an ultraviolet LED device; Figure 8 FIG. 1 is a cross-sectional view of an embodiment of a UV LED device; Figure 9 Schematic diagram of the light path of the filler with a gradient refractive index in an embodiment of an ultraviolet LED device. DETAILED DESCRIPTION

[0021] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0022] In the present invention, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in normal use, and "inside" and "outside" refer to the outline of the device. In addition, the terms "first, second, and third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first, second, and third" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. The present invention is an electrical device, so connection and interconnection both refer to conductive interconnection. Since the accompanying drawings are descriptions of the same device, the same numbers in the drawings represent the same components.

[0023] The ultraviolet LED device of the present invention comprises: a substrate; an electrode pad and a heat dissipation electrode on one side of the substrate; a dam on the edge of the other side of the substrate, the inner side of the dam being an inclined surface formed with a first reflective material; a plurality of light-emitting chips are arranged on the substrate within the dam, and the light-emitting chips and the electrode pads are correspondingly interconnected; between the dams of the substrate, the surface of the substrate outside the light-emitting chips is covered with a second reflective material, and the space between the dams is filled with a filler, which covers the chips; quartz glass is formed on top of the filler and the dams, and the quartz glass at the corresponding position on the top of each chip is a convex lens.

[0024] In one embodiment, the substrate includes an aluminum compound layer and / or copper.

[0025] In one embodiment, the substrate has two electrode pads with a thickness of 0.15 mm and a surface plated with metal copper, which serve as circuit connections for the light-emitting chip.

[0026] In one embodiment, there are four light-emitting chips, which cover all UVA, UVB or UVC bands and are connected in a 2-series-2-parallel manner. The welding with the aluminum nitride layer mainly includes eutectic welding and solder paste welding.

[0027] In one embodiment, a bidirectional Zener diode connected to the electrode pad is provided on the substrate.

[0028] In one embodiment, the second reflective material is Teflon material or UV high reflective material, and the reflectivity of the second reflective material is greater than the reflectivity of the first reflective material.

[0029] In one embodiment, the bottom of the quartz glass is square, and the upper surface is four convex lenses, which correspond one to one with four light-emitting chips, wherein the center of each light-emitting chip corresponds to the central axis of the convex lens of the integrated quartz glass.

[0030] In one embodiment, the bottom of the quartz glass is square, and the upper surface is a hemispherical convex lens.

[0031] In one embodiment, the filler material is fluorocarbon oxide.

[0032] In one embodiment, the first reflective material is an aluminum reflective mirror, a silver reflective mirror, a silicon reflective mirror, Teflon, or magnesium fluoride.

[0033] Traditional UV lamp packaging structures primarily utilize substrate dam packaging, but the absorption and shielding effects of the substrate dam limit the optical power output of small and medium-sized lamps. While the process of adding fluororesin to small-sized ceramic flat substrates improves optical power, the difficulty in extracting fluororesin prevents mass production in most domestic markets. This manufacturing difficulty results in high costs per lamp bead, making it unacceptable to end users. Conventional small-sized lamp bead light-emitting chips and quartz glass are filled with fluorocarbons, carbon silicon compounds, and fluorocarbons, each with a refractive index of approximately 1.3. The surface of the light-emitting chip has a sapphire layer with a refractive index of 1.76-1.77. The light travels from the sapphire to the quartz lens, with a refractive index of 1.44-1.46. The optical route moves from denser to less dense, and then back to denser media, with partial or even total reflection in between, preventing some light from being extracted.

[0034] To address this issue, the UV LED device of the present invention utilizes a multi-string, multi-parallel electrical connection scheme for the light-emitting chips, for example, two strings and two parallels. A filler is added between the light-emitting chip, lens, and inner cavity within the internal structure. For example, the filler is a carbon fluoride-oxygen compound with a refractive index of approximately 1.5. The light-emitting chip surface comprises a sapphire layer with a refractive index of 1.76-1.77, and a quartz lens with a refractive index of 1.44-1.46. The refractive index of the filler is lower than that of the sapphire on the light-emitting chip surface, but higher than that of the quartz glass. This reduces Fresnel losses caused by the filler itself and the interface between the air and the material, allowing light emitted from the front and sides of the light-emitting chip to be extracted again, effectively improving light extraction. Simultaneously, a reflective material, such as aluminum, is evaporated or sprayed onto the substrate dam and the light-emitting functional area of ​​the light-emitting chip. This material reflects light emitted from the side of the light-emitting chip, thus realizing a small- to medium-sized UV LED device with high-efficiency light extraction.

[0035] Reference below Figures 1 to 3The substrate 1 serves as a heat and electricity conductor for the light-emitting chip, as well as a carrier for the light-emitting chip and quartz glass, and also serves as a soldering point for the PCB. The aluminum compound layer 4 of the substrate is a crucial component for heat conduction in the light-emitting chip, with a thermal conductivity of approximately 170 W / (m·K). Its material is typically aluminum oxide or aluminum nitride. The two electrode pads 11 and 12 of the substrate are 0.15 mm thick and copper-plated, providing electrical connectivity for the light-emitting chip. The heat dissipation electrode 13 conducts heat away from the light-emitting chip. The substrate's dam 6 has an inclined inner surface coated with a first reflective material, a UV-high reflective material, and can also support the integrated quartz glass.

[0036] The light-emitting chip 2 covers all bands of UVA, UVB and / or UVC. Four light-emitting chips 2 are connected in the form of 2 series and 2 parallel. The welding with the substrate 1 mainly includes eutectic welding and solder paste welding. The light emitted by the light-emitting chip can achieve sterilization, air purification, food preservation, medical care, photocatalysis and other functions.

[0037] A bidirectional Zener diode 3 connected to the electrode pad is provided on the substrate, which mainly plays the role of offsetting external static electricity and protecting the light-emitting chip.

[0038] The surface of the stepped slope 15 of the dam 6 can be spray-coated with a first reflective material, which primarily reflects the side light emitted by the light-emitting chip. The first reflective material can be a vapor-deposited reflective material, such as an aluminum reflector, a silver reflector, or a silicon reflector. Alternatively, a layer of reflective material, such as Teflon or magnesium fluoride, can be spray-coated. This reflective material is vapor-deposited or spray-coated on the entire sloped dam of the substrate, primarily reflecting light emitted from the sidewalls of the light-emitting chip.

[0039] Between the dams of the substrate, the surface of the substrate outside the light-emitting chip is covered with a second reflective material 16, which is a highly reflective Teflon material or a UV highly reflective material, and is evaporated or sprayed on other areas of the light-emitting chip and the welding area of ​​the light-emitting functional area, and also serves to reflect the side light emission of the light-emitting chip.

[0040] In one embodiment, the second reflective material completely wraps the light emitting chip, mainly serving to reflect the light emitted from the sidewall of the light emitting chip.

[0041] Filler 8 fills the inner cavity of the quartz glass that houses the integrated light-emitting chip. Made of a carbon-fluorine-oxygen compound, it exhibits high-temperature resistance, enabling stable operation for extended periods in high-temperature environments. It is not susceptible to thermal decomposition or oxidation. It also exhibits excellent chemical resistance, withstanding erosion by most acids, alkalis, solvents, and other chemicals. It is also unaffected by ultraviolet light, oxygen, and moisture, with a refractive index in UV light of approximately 1.5. A buffer zone 19 for separating the filler from the glue is located outside the dam. After filler 8 covers the lens, the filler overflows into the buffer zone. When the dam surface contacts the silicone, the filler separates from the silicone, primarily serving to separate the filler from the glue.

[0042] refer to Figure 4 The quartz glass 7 is an integrated structure with a square bottom and four convex lenses 12 on the upper surface. The center position of each convex lens corresponds to the central axis of the light-emitting chip 2. The material is JJG2 type material, with a transmittance of more than 85% in the UV band. The luminous angle can be 30°, 60° or 90°. The connection with the substrate mainly adopts silicone bonding, inorganic welding, and nano-silver bonding packaging. It mainly extracts UV light and simultaneously protects the light-emitting chip. The center of each of the four light-emitting chips corresponds to the central axis of the convex lens of the integrated quartz glass.

[0043] In one embodiment of the present invention, the dam and the quartz glass lens on the top of the dam are an integrated metal cap with an inlaid lens.

[0044] In another embodiment of the present invention, Figure 5 As shown, the quartz glass 12 of the UV LED device has a rounded bottom and a hemispherical top surface. Made of JJG2 material, it boasts a UV transmittance exceeding 80%, and can accommodate beam angles of 30°, 60°, or 90°. Due to its larger size and the height of the spherical quartz glass, light extraction from the front and sides of the light-emitting chip differs from that of monolithic quartz glass. While UV transmittance is slightly lower, it still provides some UV light extraction.

[0045] Compared to traditional small and medium-sized packages, the light extraction rate of a simple spherical quartz lens can reach around 15-20%. By using highly reflective and high-extraction materials, adding fillers to the light-emitting chip and the integrated quartz lens cavity, and using integrated quartz glass, the light extraction rate can be increased to around 70-90%. This significant improvement in light extraction rate allows for applications in small spaces with high light output.

[0046] Compared with the traditional package made of fillers with a refractive index of 1.3, its light extraction effect can also reach about 30%. However, its working principle is from a denser medium to a less dense medium, and then to a denser medium. Some light will be reflected back in the form of light, and some light will be lost, failing to achieve a high extraction effect. The 4545 light-emitting chip under the structure of the 6868 substrate can achieve an optical power of 400-500mW, which is at the industry-leading level. The light decay of the light-emitting chip is less than 10% in room temperature aging, high temperature aging, constant temperature and humidity aging, and hot and cold shock tests. The filler does not yellow or crack. The airtightness test pass rate is >99%, and the salt spray test pass rate is >99%.

[0047] The light-emitting chip of the present invention adopts a two-string and two-parallel connection method of four light-emitting chips, but is not limited to a multi-string and multi-parallel connection method using more light-emitting chips; the filler adopts a carbon fluoride oxygen compound, but is not limited to a carbon fluoride compound, a carbon silicon compound, or a compound doped with other substances to change the refractive index.

[0048] The present invention uses an integrated quartz lens or a spherical quartz lens, but is not limited to using other packaged lenses such as iron-nickel alloy, pure nickel cap shell and quartz lens inlay.

[0049] In another embodiment of the present invention, Figure 6 shown, including: A power input electrode "+" 61 connected to an electrode pad on the copper substrate; a power input electrode pad "-" 62 connected to another electrode pad on the copper substrate; The current limiting resistor 63 acts as a voltage divider; Constant current diode 64, constant current circuit for each path; The light emitting chip 65 includes all UVA, UVB, and UVC bands, and is mainly welded to the substrate 67 using solder paste welding. Figure 6 The five light-emitting chips are first connected in series, then connected in series with current-limiting resistors and constant-current diodes, and then the five groups are connected in parallel, and then connected to 1 and 2 to form a complete path, realizing a multi-string and multi-parallel connection mode. The multi-string and multi-parallel circuit connection diagram is shown in Figure 7 The center of each light-emitting chip among the multiple light-emitting chips corresponds to the central axis of the convex lens of the integrated inlaid lens metal cap. Figure 8 Schematic diagram of the cross-section of the integrated inlaid lens metal cap. The light emitted by the light-emitting chip can achieve sterilization, air purification, food preservation, medical care, photocatalysis and other functions.

[0050] Figure 6The copper substrate is welded or bonded to the part of the metal cap with an integrated lens, and a layer of metal 66 is plated on the surface of the copper substrate. The surface plating process can be a gold plating process or a SOP process. The copper substrate 67 serves to carry the light-emitting chip and the metal cap with an integrated lens, and also has a heat and electricity conduction function. The thermal conductivity coefficient is about 300W / (m·K). The thickness of the copper substrate is 1.0-2.0mm.

[0051] refer to Figure 8 The one-piece inlaid lens metal cap shell 89 is welded to the metal surface of the copper substrate through inorganic materials, or bonded with organic materials; the cap shell of the one-piece inlaid lens metal cap shell constitutes the dam 81, and its material is iron-nickel alloy, pure nickel and other materials; the bottom of the quartz lens 88 is square and is inlaid with the dam 81 through inorganic materials. Its upper surface is a plurality of convex lenses, and the center position of each convex lens corresponds to the central axis of a light-emitting chip one by one. Its material is JJG2 type material, and the transmittance of the UV band reaches more than 85%, and the light-emitting angle can be 30°, 60° or 90°.

[0052] The reflective material on the inclined surface of the dam is a reflective material formed by vapor deposition, such as an aluminum reflector, a silver reflector, a silicon reflector, etc.; a layer of reflective material, such as Teflon, magnesium fluoride, etc., can also be sprayed. The reflective material is evaporated or sprayed on the entire inclined surface, mainly to emit the light emitted from the side wall of the light-emitting chip; the inclined surface of the side wall of the dam allows the reflective material to be evaporated or sprayed on this surface.

[0053] The filler is made of a carbon-fluoro-oxygen compound, a high-temperature resistant material that can operate stably for extended periods in high-temperature environments. It is not susceptible to thermal decomposition or oxidation. It also exhibits excellent chemical resistance, withstanding erosion by most acids, alkalis, solvents, and other chemicals, and is not susceptible to UV rays, oxygen, or moisture. Its refractive index under UV light is approximately 1.5, and the filler can be evenly dispensed onto the light-emitting chip using a piezoelectric or jet dispenser.

[0054] Figure 9 This is a schematic diagram of the light path for a filler with a gradient refractive index. The refractive index of the sapphire on the light-emitting chip surface is 1.76-1.77, the refractive index of the filler is around 1.5, and the refractive index of the quartz glass is 1.44-1.46. The ultraviolet light path radiates from the package cavity into the air, then travels from the denser medium to the less dense medium and back to the air. This allows the light emitted by the light-emitting chip to be extracted as much as possible.

[0055] The present invention also provides a method for preparing an ultraviolet LED device, comprising the steps of: providing a substrate; Fixing the light-emitting chip on the substrate; forming an electrode pad and a heat dissipation electrode on one side of the substrate; A dam is formed on the other edge of the substrate, and the inner side of the dam is an inclined surface; forming a first reflective material on the inner slope of the dam; A light-emitting chip is arranged in the middle of the substrate dam, and the light-emitting chip and the electrode pads are correspondingly interconnected; Between the dams of the substrate and outside the light emitting chip, the surface of the substrate is covered with a second reflective material. Filling between the dams; Providing quartz glass with a convex lens; The filling and the top of the dam are covered with quartz glass.

[0056] Specifically, the key integrated processes include: Die bonding: The light-emitting chip integration method uses four 4545 high-power light-emitting chips. The light-emitting chips are soldered to the light-emitting functional area of ​​the substrate through eutectic welding, solder paste welding, etc. to achieve the integrated function. The center position of each of the four light-emitting chips is concentric with the axis of the integrated quartz glass convex lens. The tolerance range is: ±50um to ensure that the light emitted by each light-emitting chip is fully extracted. This is a key process of integration; Filling: Use a metering valve type dispensing machine to dispense the filler on the light-emitting chip and the inner cavity of the side wall of the substrate dam. The horizontal surface of the filler should be kept flush with the lower surface of the integrated quartz glass. However, it cannot flow onto the horizontal step surface of the substrate dam, but can flow into the filler glue separation buffer zone. Glue dispensing on the dam surface: Use a dosage valve type glue dispensing machine to evenly dispense glue on the dam surface; Cover the lens with the dam plane: After the nozzle picks up the lens, the arm swings to the crystal fixing position, and then slowly places it on the stepped surface at a variable speed to prevent the silicone and filler from splashing and mixing. Baking: Initial baking at 100℃. Before entering the oven, use a pressing plate to press the lens together, and then bake at 150℃ for a long time.

[0057] The above examples of steps do not limit the order of the steps of the present invention, and adjustments to the steps within the scope of achieving the purpose of the invention are all within the scope of protection of the present invention.

[0058] In one embodiment, the substrate is a copper substrate, and the light-emitting chips are directly soldered on the substrate. The light-emitting chips are soldered using solder paste and connected in a multi-series and multi-parallel manner. Each light-emitting chip is connected in series with a set of constant current diodes and current limiting resistors, and then multiple light-emitting chips are connected in parallel.

[0059] Then, a dam is formed by using an integrated inlaid lens metal cap. The lens metal cap is welded or bonded to the copper substrate through inorganic or organic materials. The integrated inlaid lens metal cap surrounds the light-emitting chip to form a closed space. Filler is added directly above the light-emitting chip and contacts the lens part of the integrated inlaid lens metal cap. The inner side of the dam is an inclined surface, and a reflective material such as aluminum is evaporated on the inclined surface or a layer of reflective material such as Teflon or magnesium fluoride is sprayed on it. Multiple light-emitting chips are integrated in a limited space to achieve a high radiation flux per unit area, thereby forming a packaging structure with high reflection and high output.

[0060] This application adopts a unique structural setting, which has achieved the following beneficial effects: 1. Optimize the optical path: Fillers can fill the microscopic rough structure on the chip surface, reduce light scattering, and allow light to enter the lens more efficiently, with an extraction rate of about 70-90%.

[0061] 2. Improved thermal conductivity: High thermal conductivity fillers can quickly transfer the heat generated by the chip to the package aluminum nitride layer or heat dissipation substrate, reducing the junction temperature and avoiding light attenuation or wavelength shift caused by overheating.

[0062] 3. Improved temperature uniformity: The filler covers the chip surface, reducing local hot spots and extending LED life.

[0063] 4. Uniform light distribution: The filler can diffuse the light, reduce the uneven spot caused by the uneven chip surface or electrode shading, and improve the uniformity of light output; the single chip has high center light intensity and fast edge attenuation, while multiple chips can generate a uniform light field through reasonable arrangement and optical diffusion design. 5. Modular design: Multi-chip integrated packaging reduces the number of peripheral circuits and optical components, and the driving circuit can be shared, reducing system complexity.

[0064] This application utilizes multi-chip integration, requiring larger lenses or complex optical designs. After numerous experiments, we achieved a single-piece quartz lens and a single-piece metal cap housing with a lens embedded in it. A convex lens formed of quartz glass is embedded within the metal cap, which is then secured to the outside, providing robustness and facilitating installation.

[0065] The solution of the present application utilizes alignment of the substrate pad and the lens optical center in multi-chip integration. When installing quartz glass, a high-precision die bonder and automatic optical inspection equipment are used to achieve one-to-one alignment of the light-emitting chip center and the lens axis, with the error controlled within the range of ±0.05mm.

[0066] Multi-chip integration requires strict matching of chip parameters such as wavelength, voltage, and light intensity. The packaging front end needs to sort the various chip parameters to ensure consistency. This places strict demands on the stability of chip manufacturing. The stability of the entire package can be improved through refined sorting.

[0067] The light extraction rate of the multi-chip combined with reflective material and filler is 395% higher than that of a single chip, reflective material and filler. The light extraction rate of the multi-chip combined with reflective material and filler is 78.6% higher than that of a single lens, and 16.7% higher than that of a single lens. The extraction rate verification data results are shown below: Table 1

[0068] Table 2

[0069] The above description is merely an embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, such as the mutual combination of technical features between the embodiments, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A UV LED device, characterized in that: include: substrate; An electrode pad and a heat dissipation electrode are provided on one side of the substrate; A dam is provided on the other edge of the substrate, and an inner side of the dam is an inclined surface formed with a first reflective material; A plurality of light-emitting chips are arranged on the substrate within the dam, and the light-emitting chips and the electrode pads are correspondingly interconnected; Between the dams of the substrate, the surface of the substrate outside the light emitting chip is covered with a second reflective material. Fillers are filled between the dams, and the fillers cover the chips; Quartz glass is formed on the top of the filler and the dam, and the quartz glass at the corresponding position on the top of each chip is a convex lens.

2. The ultraviolet LED device according to claim 1, wherein The substrate includes an aluminum compound layer and / or copper.

3. The ultraviolet LED device according to claim 1, wherein The substrate has two electrode pads with a thickness of 0.15 mm and a surface plated with metal copper, which serve as circuit connections for the light-emitting chip.

4. The ultraviolet LED device according to claim 1, wherein It has 4 light-emitting chips, which cover all UVA, UVB or UVC bands and are connected in 2 series and 2 parallel modes. The welding with the aluminum nitride layer mainly includes eutectic welding and solder paste welding.

5. The ultraviolet LED device according to claim 1, wherein A bidirectional Zener diode connected to an electrode pad is provided on the substrate.

6. The ultraviolet LED device according to claim 1, wherein The second reflective material is Teflon material or UV high reflective material, and the reflectivity of the second reflective material is greater than the reflectivity of the first reflective material.

7. The ultraviolet LED device according to claim 1, wherein The bottom of the quartz glass is square, and the upper surface is four convex lenses. The four convex lenses correspond to the four light-emitting chips one by one, and the center of each light-emitting chip corresponds to the central axis of the convex lens of the integrated quartz glass.

8. The ultraviolet LED device according to claim 1, wherein The bottom of the quartz glass is square and the upper surface is a hemispherical convex lens.

9. The ultraviolet LED device according to claim 1, wherein: The filling material is fluorocarbon.

10. The ultraviolet LED device according to claim 1, wherein: The first reflective material is an aluminum reflector, a silver reflector, a silicon reflector, Teflon, or magnesium fluoride.

11. A method for preparing an ultraviolet LED device, characterized in that: Including steps: providing a substrate; fixing a plurality of light-emitting chips on a substrate; A dam is formed on the edge of one side of the light-emitting chip of the substrate, the dam surrounds the multiple chips, and the inner side of the dam is an inclined surface; Forming electrode pads and heat dissipation electrodes on the substrate, wherein the light emitting chip and the electrode pads are correspondingly interconnected; forming a first reflective material on the inner slope of the dam; Between the dams of the substrate and outside the light emitting chip, the surface of the substrate is covered with a second reflective material. Filling between the dams; Providing quartz glass with a convex lens; The filling and the top of the dam are covered with quartz glass.

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