An LED device and its packaging method

Abstract

The present invention discloses an LED device and its packaging method. The key points of the technical solution are that the LED device includes a substrate, a metallization circuit layer is provided on the periphery of the substrate, a light window cover plate is provided on the metallization circuit layer, the light window cover plate includes a metal part, a light passing hole and a light window lens covering the light passing hole are respectively provided on the metal part, the light window cover plate is arranged above the substrate so that a cavity is formed between the light window cover plate and the substrate, an LED chip is arranged in the cavity, and the LED chip is fixed on the substrate. The light window lens is packaged with the metal part by a fusion welding or sintering process to form the light window cover plate, the light window cover plate is assembled onto the metallization circuit layer of the substrate through corresponding tooling fixtures, and finally the light window cover plate and the substrate are sealed together by a resistance welding or fusion welding process. In the present invention, the substrate, the metal part and the light window lens all adopt inorganic materials, and the solder, the metallization circuit layer and all the plating layers also adopt inorganic materials, which can achieve high airtightness, high reliability and inorganic packaging.

Description

Technical Field

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

[0002] As LED technology matures, LED has been widely used in all walks of life. In recent years, the development of 5G technology has driven the Internet of Everything and smart homes, giving light different meanings. Among them, infrared LEDs have played an important role in security, face recognition, machine vision, and intelligent control. Due to people's concern about their own health, ultraviolet disinfection and sterilization products have gradually entered the public eye. Various medical and household ultraviolet LED disinfection products and solutions closely related to life are emerging in an endless stream. LED is no longer just used as a lighting source. With the transformation and diversification of application scenarios, new requirements have been put forward for the reliability of LEDs, especially in the invisible light band. The physical and chemical properties of light sources can easily cause organic materials such as silicone or epoxy resins to age and yellow, and the oxygen permeability, moisture permeability and light transmission properties change, resulting in device failure or dead light. The traditional silicone or epoxy resin packaging form can no longer meet the reliability requirements of the product.

[0003] Therefore, it is urgent to seek a reliable airtight, inorganic packaging technology. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an LED device and a packaging method thereof, which has high airtightness and inorganic packaging compared to traditional LED light sources, and is mainly used in light source devices that have high airtightness requirements and are not suitable for organic material packaging.

[0005] The present invention is achieved through the following technical solutions.

[0006] An LED device, characterized in that: it includes a substrate 2, a metallized circuit layer 4 is provided on the periphery of the substrate 2, a light window cover 1 is provided on the metallized circuit layer 4, the light window cover 1 includes a metal part 101, and the metal part 101 is respectively provided with a light through hole and a light window lens 102 covering the light through hole, the light window cover 1 is a cavity structure, the light window cover 1 is arranged above the substrate 2 so that a cavity 6 is formed between the light window cover 1 and the substrate 2, an LED chip 3 is provided in the cavity 6, the LED chip 3 is fixed on the substrate 2, and the substrate 2 is a planar structure.

[0007] The LED device as described above is characterized in that: a solder 5 for welding the light window lens 102 and the metal part 101 is provided between the light window lens 102 and the metal part 101 , the solder 5 is ring-shaped and made of inorganic material.

[0008] The LED device as described above is characterized in that: the substrate 2 is made of one of ceramic, aluminum, copper, and aluminum silicon carbide substrate.

[0009] The LED device as described above is characterized in that: the light window lens 102 is made of quartz glass, and the shape of the light window lens 102 is one of square, circular, ellipsoidal, and hemispherical.

[0010] The LED device as described above is characterized in that: the metal part 101 is made of Kovar alloy, copper, or aluminum. An extended metal solder edge is provided at the bottom edge part of the metal part 101. The metal solder edge is welded to the metallization line layer 4. The width H1 of the metal solder edge is ≥ 0.3 mm, the thickness H2 of the metallization line layer 4 is ≥ 60 μm, a coating is provided on the surface of the metallization line layer 4, and the material of the coating is gold or nickel-gold.

[0011] The LED device as described above is characterized in that: a nickel plating layer is provided on the surface of the metal part 101, and the depth H3 of the cavity 6 is ≥ 0.5 mm.

[0012] A packaging method for the LED device as described above is characterized by including:

[0013] An annular metallization line layer 4 is provided at the edge of the substrate 2. The thickness of the metallization line layer 4 is not less than 60 μm, and the surface of the metallization line layer 4 is treated by gold plating or nickel-gold plating;

[0014] The LED chip 3 is bonded to the substrate 2 by a solder paste die bonding or eutectic process;

[0015] The metal part 101 is fabricated by die stamping, and the surface of the metal part 101 is treated by nickel plating;

[0016] A quartz glass sheet matching the size of the light passing hole is cut to form the light window lens 102. A coating treatment is performed on an annular area with a width ≤ 0.5 mm at the edge of the light window lens 102, and the coating thickness is ≥ 10 μm. The light window lens 102 is installed into the metal part 101 through a tooling fixture, and the matching contact part of the light window lens 102 and the metal part 101 is welded by a fusion welding process to form the light window cover 1, or solder 5 is added to sinter the light window lens 102 and the metal part 101 into the light window cover 1;

[0017] The light window cover 1 is assembled to the metallization line layer 4 of the substrate 2 through a fixture, and the light window cover 1 and the substrate 2 are sealed together by a resistance welding process or a fusion welding process to form an LED device.

[0018] The packaging method for the LED device as described above is characterized in that:

[0019] The resistance welding process is parallel seam welding, and the fusion welding process is laser welding.

[0020] As described above, the encapsulation method of the LED device is characterized in that: the solder 5 is composed of TiCuBiZnMn, where Ti accounts for 6.8%-25%, Cu accounts for 19.6%-34%, Bi accounts for 4.2%-7.3%, Zn accounts for 21%-37%, and Mn accounts for 0.56%-1.2%.

[0021] As described above, the encapsulation method of the LED device is characterized in that: the coating on the edge of the optical window lens 102 is composed of nickel-gold or copper.

[0022] Compared with the prior art, the present invention has the following advantages.

[0023] 1. In the present invention, the substrate, metal parts, and optical window lens are all made of inorganic materials, and the solder, metallized circuit layer, and all coatings are also made of inorganic materials. The optical window lens and the metal parts are sealed together to form an optical window cover plate by using a sintering process or a fusion welding process, and the optical window cover plate and the substrate are combined together to form an LED device by using a resistance welding or fusion welding process, realizing high airtightness and inorganic encapsulation.

[0024] 2. Compared with traditional LED light sources, the present invention has good airtightness, inorganic encapsulation, and a simple structure, and is mainly applied to light source devices with high requirements for airtightness and reliability and unsuitable for organic material encapsulation. Especially in UVC and high-power IR LED light source devices, it can better solve the problems of easy lens dropping, serious light decay of the device, and insufficient airtightness in existing glue encapsulation and the same type of inorganic encapsulation solutions with glass or quartz optical windows. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the substrate structure of the LED device of the present invention.

[0026] Figure 2 It is a schematic cross-sectional view of the structure of the first embodiment of the LED device of the present invention. In the figure, the optical window lens and the metal parts are sintered and connected, the optical window cover plate is a cavity structure, the substrate is a planar structure, and the shape of the optical window lens is square or circular.

[0027] Figure 3 It is a schematic cross-sectional view of the structure of the second embodiment of the LED device of the present invention. In the figure, the optical window lens and the metal parts are sintered and connected, the optical window cover plate is a cavity structure, the substrate is a planar structure, and the shape of the optical window lens is hemispherical or ellipsoidal.

[0028] Figure 4 It is a schematic cross-sectional view of the structure of the third embodiment of the red LED device of the present invention. In the figure, the optical window lens and the metal parts are sintered and connected, the optical window cover plate is a planar structure, the substrate is a cavity structure, and the shape of the optical window lens is hemispherical or ellipsoidal.

[0029] Figure 5 It is a schematic cross-sectional view of the structure of the fourth embodiment of the red LED device of the present invention. In the figure, the optical window lens is welded to the metal part. The optical window cover plate is of a planar structure, the substrate is of a cavity structure, and the shape of the optical window lens is square or circular.

[0030] Figure 6 It is a schematic cross-sectional view of the structure of the fifth embodiment of the LED device of the present invention. In the figure, the optical window lens is welded to the metal part. The optical window cover plate is of a planar structure, the substrate is of a cavity structure, and the shape of the optical window lens is hemispherical or ellipsoidal.

[0031] In the figure: 1 is the optical window cover plate; 101 is the metal part; 102 is the optical window lens; 2 is the substrate; 3 is the LED chip; 4 is the metallization line layer; 5 is the solder; 6 is the cavity. Specific embodiments

[0032] The technical features of the present invention will be further described in detail below with reference to the accompanying drawings so that those skilled in the art can understand.

[0033] An LED device includes a substrate 2. A metallization line layer 4 is provided on the periphery of the substrate 2. An optical window cover plate 1 is provided on the metallization line layer 4. The optical window cover plate 1 includes a metal part 101. A light-passing hole and an optical window lens 102 covering the light-passing hole are respectively provided on the metal part 101. The size of the optical window cover plate 1 matches the size of the substrate 2. The optical window cover plate 1 has a cavity structure. The optical window cover plate 1 is provided above the substrate 2 so that a cavity 6 is formed between the optical window cover plate 1 and the substrate 2. One or more LED chips 3 are provided in the cavity 6 and are fixed on the substrate 2.

[0034] Further, the optical window lens 102 is encapsulated with the metal part 101 into the optical window cover plate 1 by using a solder 5 and a fusion welding process. The shape of the optical window cover plate 1 is not limited to square, circular, conical, etc.; the solder 5 is in a ring shape and is made of an inorganic material.

[0035] For the LED device as described above, the depth H3 of the cavity 6 is ≥ 0.5 mm.

[0036] For the LED device as described above, the substrate 2 is preferably of a planar structure. Of course, it can also be a structure with a cavity. When the substrate 2 is of a planar structure, the corresponding optical window cover plate 1 is of a cavity structure; when the substrate 2 is a cavity structure with a step, the corresponding optical window cover plate 1 is of a planar structure, and the height H4 of the step is ≥ 0.35 mm, which is convenient for matching and assembling and sealing without damaging the gold wire.

[0037] A circuit pattern is provided on the substrate 2. The material of the substrate 2 can be a ceramic substrate, or a metal substrate such as aluminum or copper, or other composite materials with high thermal conductivity and light reflection characteristics, such as aluminum silicon carbide substrate, metal substrate coated with graphene, etc.

[0038] Furthermore, aluminum is plated on the surface of the ceramic substrate or a high-reflection coating material such as PTFE is used to further improve the overall light output performance of the device in the invisible light band, especially in the UVC band.

[0039] When the optical window lens 102 is sintered and connected to the metal part 101, a solder 5 for welding and connecting the optical window lens 102 and the metal part 101 is provided between the optical window lens 102 and the metal part 101. The solder 5 is annular and is made of inorganic materials. The components of the solder 5 are TiCuBiZnMn, where Ti accounts for 6.8%-25%, Cu accounts for 19.6%-34%, Bi accounts for 4.2%-7.3%, Zn accounts for 21%-37%, and Mn accounts for 0.56%-1.2%.

[0040] The optical window lens 102 and the metal part 101 can also be connected by fusion welding, in which case the solder 5 is not required.

[0041] For the LED device as described above, the material of the optical window lens 102 is quartz glass. The shape of the optical window lens 102 is preferably one of a square, a circle, an ellipsoid, and a hemisphere. When the shape of the optical window lens 102 is different, the shape of the metal part 101 will be adaptively changed for easy welding.

[0042] For the LED device as described above, the material of the metal part 101 is Kovar alloy, copper, or aluminum, and the surface of the metal part 101 needs to be nickel-plated. There is an extended metal welding edge at the bottom edge of the metal part 101. The width H1 of the metal welding edge is ≥0.3 mm, and the metal welding edge is welded and connected to the metallized circuit layer 4. The function of the metallized circuit layer 4 is to seal the optical window cover 1 and the substrate 2 into one body through resistance welding or fusion welding process; the metallized circuit layer 4 is also annular, its thickness H2 is ≥60 μm, and a coating is provided on the surface of the metallized circuit layer 4. The material of the coating is gold or nickel-gold.

[0043] This patent also claims to protect a packaging method for the LED device as described above, specifically as follows:

[0044] An annular metallized circuit layer 4 is provided on the edge of the substrate 2. The thickness H2 of the metallized circuit layer 4 is ≥60 μm, and the surface of the metallized circuit layer 4 is treated with gold plating or nickel-gold plating;

[0045] The LED chip 3 is bonded to the substrate 2 through a solder paste die bonding or eutectic process;

[0046] The metal part 101 is fabricated by precision die stamping, and the surface of the metal part 101 is nickel-plated.

[0047] A quartz glass sheet matching the size of the light passing hole is cut to make the optical window lens 102. A plating treatment is performed on an annular area within 0.5 mm of the edge of the optical window lens 102. The plating components are nickel-gold or copper, and the plating thickness is ≥ 10 μm. The optical window lens 102 is installed into the metal part 101 through a tooling fixture, and a fusion welding process is used to weld the plating area at the edge of the quartz glass and the mating contact part of the metal part to make the optical window cover 1. This fusion welding process needs to be carried out in an atmosphere of high-purity nitrogen or a mixture of nitrogen and helium to achieve a better airtightness effect. Or solder 5 is added and a sintering process is used to seal the optical window lens 102 and the metal part 101 into the optical window cover 1.

[0048] The optical window cover 1 is assembled onto the metallized circuit layer 4 of the substrate 2 through a fixture, and the optical window cover 1 and the substrate 2 are sealed together through a resistance welding process or a fusion welding process to make an LED device.

[0049] Furthermore, the resistance welding process is parallel seam welding, the fusion welding process is laser welding, and the solder 5 is made of a powder or paste mixture prepared by mixing two or more of the raw materials of gold, germanium, indium, tin, silver, copper, boron, antimony, and aluminum in specific proportions. Specifically, the components of the solder 5 are TiCuBiZnMn, where Ti accounts for 6.8% - 25%, Cu accounts for 19.6% - 34%, Bi accounts for 4.2% - 7.3%, Zn accounts for 21% - 37%, and Mn accounts for 0.56% - 1.2%.

[0050] In the present invention, the substrate 2, the metal part 101, and the optical window lens 102 all adopt inorganic materials, and the solder, the metallized circuit layer, and all the plating layers also adopt inorganic materials. A sintering process or a fusion welding process is used to seal the optical window lens 102 and the metal part 101 into an optical window cover, and a resistance welding or a fusion welding process is used to combine the optical window cover and the substrate 2 into an LED device, achieving high airtightness and inorganic encapsulation.

[0051] Compared with traditional LED light sources, the present invention has good airtightness, inorganic encapsulation, and a simple structure, and is mainly applied to light source devices with high requirements for airtightness and reliability and unsuitable for organic material encapsulation. Especially in UVC and high-power IR LED light source devices, it can better solve the problems of easy lens dropping of glass or quartz optical windows, serious light decay of devices, and insufficient airtightness in existing glue encapsulation and the same type of inorganic encapsulation solutions.

[0052] The embodiments described in the present invention are only descriptions of the preferred embodiments of the present invention, and do not limit the inventive concept and scope. Without departing from the design concept of the present invention, various modifications and improvements made by those skilled in the art to the technical solutions of the present invention shall fall within the protection scope of the present invention.

Claims

1. An LED device, characterized in that: It includes a substrate (2), a metallized circuit layer (4) is provided on the periphery of the substrate (2), a light window cover plate (1) is provided on the metallized circuit layer (4), the light window cover plate (1) includes a metal part (101), a light passing hole and a light window lens (102) covering the light passing hole are respectively provided on the metal part (101), the light window cover plate (1) is of a cavity structure, the light window cover plate (1) is arranged above the substrate (2) so that a cavity (6) is formed between the light window cover plate (1) and the substrate (2), an LED chip (3) is provided in the cavity (6), the LED chip (3) is fixed on the substrate (2), and the substrate (2) is of a planar structure; A solder (5) for welding and connecting the light window lens (102) and the metal part (101) is provided between the light window lens (102) and the metal part (101), the solder (5) is annular, and the solder (5) is made of an inorganic material; The material of the substrate (2) is one of ceramics, aluminum, copper, and aluminum silicon carbide substrate; The material of the light window lens (102) is quartz glass, and the shape of the light window lens (102) is one of square, circular, ellipsoidal, and hemispherical; The material of the metal part (101) is Kovar alloy, copper or aluminum. An extended metal solder edge is provided at the bottom edge part of the metal part (101), and the metal solder edge is welded and connected to the metallized circuit layer (4). The width H1 of the metal solder edge is ≧0.3 mm, the thickness H2 of the metallized circuit layer (4) is ≧60 μm, a coating is provided on the surface of the metallized circuit layer (4), and the material of the coating is gold or nickel gold.

2. The LED device according to claim 1, wherein: A nickel plating layer is provided on the surface of the metal part (101), and the depth H3 of the cavity (6) is ≧0.5 mm.

3. A packaging method for the LED device according to claim 1 or 2, characterized in that It includes: An annular metallized circuit layer (4) is provided on the edge of the substrate (2), the thickness of the circuit layer of the metallized circuit layer (4) is not less than 60 μm, and the surface of the metallized circuit layer (4) is subjected to gold plating or nickel gold treatment; The LED chip (3) is bonded to the substrate (2) by a solder paste die bonding or eutectic process; The metal part (101) is manufactured by die stamping, and the surface of the metal part (101) is nickel plated; A quartz glass sheet matching the size of the light passing hole is cut to form the light window lens (102). A plating treatment is performed on an annular area with a width of ≦0.5 mm at the edge of the light window lens (102), and the plating thickness is ≧10 μm. The light window lens (102) is installed in the metal part (101) through a tooling fixture, and the matching contact part of the light window lens (102) and the metal part (101) is welded by a fusion welding process to form the light window cover plate (1), or a solder (5) is added to sinter the light window lens (102) and the metal part (101) into the light window cover plate (1); The light window cover plate (1) is assembled to the metallized circuit layer (4) of the substrate (2) through a fixture, and the light window cover plate (1) and the substrate (2) are sealed into one body by a resistance welding process or a fusion welding process to manufacture an LED device.

4. The encapsulation method of the LED device according to claim 3, wherein: The resistance welding process is parallel seam welding, and the fusion welding process is laser welding.

5. The encapsulation method of the LED device according to claim 3, characterized in that: The solder (5) is composed of TiCuBiZnMn, where Ti accounts for 6.8% - 25%, Cu accounts for 19.6% - 34%, Bi accounts for 4.2% - 7.3%, Zn accounts for 21% - 37%, and Mn accounts for 0.56% - 1.2%.

6. The encapsulation method of the LED device according to claim 3, characterized in that: The coating on the edge of the optical window lens (102) is composed of nickel-gold or copper.

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