A COB packaged device

Abstract

This utility model discloses a COB (Chip-on-Board) packaging device, which includes a substrate, multiple light-emitting chips, a wavelength conversion layer, and a light-transmitting adhesive layer. The substrate has a receiving groove, and the multiple light-emitting chips are spaced apart in the receiving groove. The wavelength conversion layer covers at least the front side of the multiple light-emitting chips and is filled with scattering particles. The light-transmitting adhesive layer fills the receiving groove and covers the wavelength conversion layer. By filling the wavelength conversion layer with scattering particles, the COB packaging device can scatter the light emitted by the light-emitting chips, allowing the light to be fully mixed in the wavelength conversion layer, resulting in uniform light output. The light is emitted from the light-transmitting adhesive layer and then projected by a lens to form a uniform light spot. This eliminates dark areas caused by the spacing between the light-emitting chips and dark lines caused by the electrodes of the light-emitting chips, significantly improving the light spot quality of secondary optics.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor light-emitting technology, and in particular to a COB packaged device. Background Technology

[0002] Traditional COB (Chip-on-Board) packages consist of a substrate, multiple LED chips mounted on the substrate, and a phosphor layer mounted on the substrate covering all the LED chips. To improve optical quality, a lens is typically placed above the traditional COB package to perform secondary optical processing on the light emitted by the LED chips.

[0003] In traditional COB packaged devices, after the LED chip emits light through a phosphor layer, the front side of the phosphor layer forms the light-emitting surface. Due to the gaps between adjacent LED chips and the fact that the electrodes on the front side of each LED chip do not emit light, the light emitted from the light-emitting surface of the phosphor layer is uneven when projected through a lens. Specifically, the light spot area corresponding to the gap between LED chips is relatively dark, and the light spot area corresponding to each LED chip also has inconspicuous dark lines due to the electrodes. Therefore, the uniformity of the light spot projected by the lens in traditional COB packaged devices is poor, and the light spot quality of secondary optics needs to be improved. Summary of the Invention

[0004] To overcome the problems of poor uniformity of the light spot projected by the lens in traditional COB packaged devices and the need to improve the quality of the light spot in secondary optics, this utility model provides a COB packaged device.

[0005] A COB packaged device, comprising: The substrate is provided with a receiving groove; Multiple light-emitting chips are spaced apart in the receiving groove; A wavelength conversion layer, which at least covers the front surface of the plurality of light-emitting chips and is filled with scattering particles; and A light-transmitting adhesive layer fills the receiving groove and covers the wavelength conversion layer.

[0006] In one embodiment, the light-transmitting adhesive layer is a fluorescent adhesive layer.

[0007] In one embodiment, the light-transmitting adhesive layer is filled with scattering particles.

[0008] In one embodiment, the wavelength conversion layer covers the front and sides of the plurality of light-emitting chips.

[0009] In one embodiment, the thickness of the light-transmitting adhesive layer is less than the thickness of the wavelength conversion layer covering the front side of the light-emitting chip.

[0010] In one embodiment, the wavelength conversion layer covers only the front side of the plurality of light-emitting chips, and the light-transmitting adhesive layer fills the receiving groove, covers the sides of the plurality of light-emitting chips, and covers both the sides and the front side of the wavelength conversion layer.

[0011] In one embodiment, the thickness of the wavelength conversion layer is less than the thickness of the light-transmitting adhesive layer covering the front side of the wavelength conversion layer.

[0012] A COB packaged device, comprising: The substrate is provided with a receiving groove; Multiple light-emitting chips are spaced apart in the receiving groove; The first wavelength conversion layer is disposed only on the front side of the plurality of light-emitting chips; A second wavelength conversion layer is disposed only on the front side of the first wavelength conversion layer; and A light-transmitting adhesive layer fills the receiving groove, covers the side of the first wavelength conversion layer, and covers the front and side of the second wavelength conversion layer. The light-transmitting adhesive layer is filled with scattering particles.

[0013] In one embodiment, the thickness of the first wavelength conversion layer and the thickness of the second wavelength conversion layer are both less than the thickness of the light-transmitting adhesive layer covering the front side of the second wavelength conversion layer.

[0014] In one embodiment, the substrate includes a base plate and a dam on one side surface of the base plate, the dam and the base plate enclosing the receiving groove.

[0015] The aforementioned COB packaged device fills the wavelength conversion layer or the outermost transparent adhesive layer on the light-emitting chip with scattering particles. These scattering particles can scatter the light emitted by the light-emitting chip, allowing the light to be fully mixed in the wavelength conversion layer or the transparent adhesive layer, resulting in uniform light output. This, in turn, can project a uniform light spot through a lens, eliminating dark areas caused by the spacing between the light-emitting chips and dark lines caused by the electrodes of the light-emitting chips, thus significantly improving the light spot quality of the secondary optics. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view showing a first embodiment of the COB packaged device of this utility model; Figure 2 A cross-sectional view of a second embodiment of the COB packaging device of this utility model is shown; Figure 3 This is a cross-sectional view showing a third embodiment of the COB packaged device of this utility model.

[0017] Explanation of reference numerals in the attached figures: 100 - COB packaged device; 110 - substrate; 112 - receiving groove; 114 - substrate; 116 - dam; 120 - light-emitting chip; 130 - wavelength conversion layer; 140 - light-transmitting adhesive layer; 150 - first wavelength conversion layer; 160 - second wavelength conversion layer. Detailed Implementation

[0018] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0019] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0020] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0021] Please see Figure 1 , Figure 1 This diagram shows a cross-sectional view of a first embodiment of the COB packaging device of this invention. The COB packaging device 100 provided in this first embodiment includes a substrate 110, a plurality of light-emitting chips 120, a wavelength conversion layer 130, and a light-transmitting adhesive layer 140. The substrate 110 has a receiving groove 112. The plurality of light-emitting chips 120 are spaced apart in the receiving groove 112. The wavelength conversion layer 130 covers at least the front side of the plurality of light-emitting chips 120 and is filled with scattering particles. The light-transmitting adhesive layer 140 fills the receiving groove 112 and covers the wavelength conversion layer 130.

[0022] By filling the wavelength conversion layer 130 with scattering particles, the scattering particles can scatter the light emitted by the light-emitting chip 120, allowing the light to be fully mixed in the wavelength conversion layer 130, resulting in uniform light output. This light is emitted from the light-transmitting adhesive layer 140 and then projected through a lens to form a uniform light spot. This eliminates dark areas caused by the spacing between the light-emitting chips 120 and dark lines caused by the electrodes of the light-emitting chips 120, significantly improving the light spot quality of the secondary optics. Moreover, the wavelength conversion layer 130 has better thermal conductivity, and the heat generated by its excitation light is conducted downwards through the substrate 110, improving the heat dissipation effect of the COB packaged device 100.

[0023] The substrate 110 is a circuit board with a receiving groove 112 on it. The receiving groove 112 contains pads, which can be connected to the electrodes of the light-emitting chip 120 via bonding wires (not shown). Furthermore, the circuit board can be, but is not limited to, a ceramic substrate or a metal substrate, which has better heat dissipation.

[0024] The plurality of light-emitting chips 120 may be at least three light-emitting chips 120, and each light-emitting chip 120 may be, but is not limited to, an LED chip. The LED chip is not limited to a vertical chip; it may be a flip chip or a horizontal chip. The emission color of all LED chips may be, but is not limited to, blue LED chips. In other embodiments, all LED chips may have two or more emission colors.

[0025] The wavelength conversion layer 130 covers the front and sides of multiple light-emitting chips 120, and completely covers all light-emitting chips 120. It can provide a larger light mixing space, resulting in better light mixing effect of the light emitted by the light-emitting chips 120 and more uniform light output.

[0026] The wavelength conversion layer 130 contains wavelength conversion particles that can change the wavelength of light incident upon it, thereby changing the color of the light. The wavelength conversion particles can be fluorescent materials, specifically including at least one of yellow, red, and green fluorescent materials that emit yellow light and excite red and green light. In this embodiment, the wavelength conversion layer 130 is a yellow phosphor layer, while the light-emitting chip 120 is a blue LED chip, whose emitted blue light is converted into white light by the yellow phosphor layer.

[0027] Furthermore, the wavelength conversion particles have a particle size of 10μm to 20μm. The smaller the particles, the easier they are to diffuse outwards, thus improving the situation where wavelength conversion particles tend to accumulate in the center. The particle size of the wavelength conversion particles can be, but is not limited to, 15μm.

[0028] It should be noted that the scattering particles filling the wavelength conversion layer 130 are made of known materials, including but not limited to: SiO2, TiO2, ZnO, BaSO4, CaSO4, MgCO3, Al(OH)3, synthetic silica, glass beads, and diamond. The size of the scattering particles is suitable for the formation of scattered light; for example, the diameter of the scattering particles is 5 μm to 7 μm.

[0029] The light-transmitting adhesive layer 140 is a fluorescent adhesive layer, which can adjust the color temperature of the light spot projected through the lens to achieve the desired effect, further improving the quality of the light spot. In other embodiments, the light-transmitting adhesive layer 140 can be a transparent adhesive layer, molded from light-transmitting resin, without being filled with phosphor, which can protect the wavelength conversion layer 130. The concentration of phosphor in the light-transmitting adhesive layer 140 is lower than the concentration of phosphor in the wavelength conversion layer 130.

[0030] Furthermore, the light-transmitting adhesive layer 140 is also filled with scattering particles, which can further scatter the light. The light is re-mixed within the light-transmitting adhesive layer 140, resulting in more uniform light output and better uniformity of the light spot projected through the lens. It is understood that the specific content of the scattering particles within the light-transmitting adhesive layer 140 can be referred to the above description and will not be repeated here. In alternative embodiments, the light-transmitting adhesive layer 140 is only a fluorescent adhesive layer and is not filled with scattering particles; or the light-transmitting adhesive layer 140 is only filled with scattering particles and does not contain phosphor.

[0031] The thickness t2 of the light-transmitting adhesive layer 140 is less than the thickness t1 of the wavelength conversion layer 130 covering the front side of the light-emitting chip 120. Since the color conversion and light scattering mainly occur in the wavelength conversion layer 130, while the light-transmitting adhesive layer 140 is used to further optimize color temperature adjustment and light scattering, the thickness of the light-transmitting adhesive layer 140 is small, which can reduce the amount of material used and save costs.

[0032] Please see Figure 2 , Figure 2 A cross-sectional view of a second embodiment of the COB packaging device of the present invention is shown. Compared with the COB packaging device 100 in the above embodiment, in this embodiment, the wavelength conversion layer 130 of the COB packaging device 100 only covers the front side of the plurality of light-emitting chips 120, while the light-transmitting adhesive layer 140 fills the receiving groove 112 and covers the side side of the plurality of light-emitting chips 120, as well as the side side and front side of the wavelength conversion layer 130.

[0033] By filling the wavelength conversion layer 130 with scattering particles, the scattering particles can scatter the light emitted by the light-emitting chip 120, allowing the light to be fully mixed in the wavelength conversion layer 130, resulting in uniform light output. This light is then emitted from the translucent adhesive layer 140 and projected through a lens to form a uniform light spot. This eliminates dark areas caused by the spacing between the light-emitting chips 120 and dark lines caused by the electrodes of the light-emitting chips 120, significantly improving the light spot quality of the secondary optics. Furthermore, the wavelength conversion layer 130 has better thermal conductivity, allowing the heat generated by the excitation light to be conducted downwards through the substrate 110, improving the heat dissipation effect of the COB packaged device 100. Since the wavelength conversion layer 130 only covers the front side of the light-emitting chip 120, its usage is reduced, which helps to lower costs. The translucent adhesive layer 140 serves to seal the light-emitting chip 120 and the wavelength conversion layer 130.

[0034] Other configurations of the wavelength conversion layer 130 can be found in the above embodiments and will not be elaborated here.

[0035] The light-transmitting adhesive layer 140 is a fluorescent adhesive layer, which can adjust the color temperature of the light spot projected through the lens to achieve the desired effect, further improving the quality of the light spot. In other embodiments, the light-transmitting adhesive layer 140 can be a transparent adhesive layer, molded from light-transmitting resin, without being filled with phosphor, which can protect the wavelength conversion layer 130. The concentration of phosphor in the light-transmitting adhesive layer 140 is lower than the concentration of phosphor in the wavelength conversion layer 130.

[0036] Furthermore, the light-transmitting adhesive layer 140 is also filled with scattering particles, which can further scatter light. The light is re-mixed within the light-transmitting adhesive layer 140, resulting in more uniform light output and better uniformity of the light spot projected through the lens. It is understood that the specific content of the scattering particles within the light-transmitting adhesive layer 140 can be referred to the description in the above embodiments, and will not be repeated here. In alternative embodiments, the light-transmitting adhesive layer 140 is only a fluorescent adhesive layer and is not filled with scattering particles; or the light-transmitting adhesive layer 140 is only filled with scattering particles and does not contain phosphor.

[0037] The thickness t1 of the wavelength conversion layer 130 is less than the thickness t2 of the front side of the wavelength conversion layer 130 covered by the light-transmitting adhesive layer 140, thereby improving the color conversion and light scattering effect of light emission in the light-transmitting adhesive layer 140.

[0038] As for the other aspects of the COB packaging device 100 in this embodiment, they are basically the same as the other aspects of the COB packaging device 100 in the above embodiments. The specific content can be referred to the description of the above embodiments, and will not be repeated here.

[0039] Please see Figure 3 , Figure 3A cross-sectional view of a third embodiment of the COB packaging device of this utility model is shown. Compared with the COB packaging device 100 in the second embodiment described above, the COB packaging device 100 in this embodiment has three adhesive layers on the light-emitting chip 120, namely a first wavelength conversion layer 150, a second wavelength conversion layer 160, and a light-transmitting adhesive layer 140. The first wavelength conversion layer 150 is only disposed on the front side of the plurality of light-emitting chips 120. The second wavelength conversion layer 160 is only disposed on the front side of the first wavelength conversion layer 150. The light-transmitting adhesive layer 140 fills the receiving groove 112, covers the side surface of the first wavelength conversion layer 150, and covers the front and side surfaces of the second wavelength conversion layer 160. The light-transmitting adhesive layer 140 is filled with scattering particles.

[0040] By filling the light-scattering adhesive layer 140 with scattering particles, the light is scattered and mixed within the layer, improving the uniformity of the emitted light. This enhances the quality of the light spot projected through the lens, eliminating dark areas caused by the spacing between the light-emitting chips 120 and dark lines caused by the electrodes of the light-emitting chips 120, significantly improving the quality of the light spot in secondary optics. The first wavelength conversion layer 150 and the second wavelength conversion layer 160 work together to adjust the color temperature of the light spot projected through the lens, achieving the desired color temperature and further improving the light spot quality.

[0041] The specific configuration of the first wavelength conversion layer 150 and the second wavelength conversion layer 160 can be referred to the above embodiment, and will not be repeated here. Furthermore, both the first wavelength conversion layer 150 and the second wavelength conversion layer 160 are yellow fluorescent adhesive layers, wherein the concentration of phosphor in the first wavelength conversion layer 150 is greater than the concentration of phosphor in the second wavelength conversion layer 160.

[0042] The thickness t0 of the first wavelength conversion layer 150 and the thickness t1 of the second wavelength conversion layer 160 are both less than the thickness t2 of the front side of the light-transmitting adhesive layer 140 covering the second wavelength conversion layer 160. As a result, the light entering the light-transmitting adhesive layer 140 has a larger mixing space and is dispersed by more scattering particles, thereby improving the scattering effect of light in the light-transmitting adhesive layer 140.

[0043] The substrate 110 includes a substrate 114 and a dam 116 on one side of the substrate 114. The dam 116 and the substrate 114 enclose each other to form a receiving groove 112. All light-emitting chips 120, the first wavelength conversion layer 150, the second wavelength conversion layer 160, and the light-transmitting adhesive layer 140 are housed in the receiving groove 112.

[0044] As for the other aspects of the COB packaging device 100 in this embodiment, they are basically the same as the other aspects of the COB packaging device 100 in the second embodiment above. The specific details can be referred to the description of the second embodiment above, and will not be repeated here.

[0045] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0046] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A COB packaged device, characterized by, include: The substrate (110) is provided with a receiving groove (112); Multiple light-emitting chips (120) are spaced apart in the receiving groove (112); A wavelength conversion layer (130) is provided, which at least covers the front side of the plurality of light-emitting chips (120) and is filled with scattering particles. as well as A light-transmitting adhesive layer (140) fills the receiving groove (112) and covers the wavelength conversion layer (130).

2. The COB packaging device according to claim 1, wherein, The light-transmitting adhesive layer (140) is a fluorescent adhesive layer.

3. The COB packaging device according to claim 1, wherein, The light-transmitting adhesive layer (140) is filled with scattering particles.

4. The COB packaging device according to claim 1, 2 or 3, characterized in that, The wavelength conversion layer (130) covers the front and sides of the plurality of light-emitting chips (120).

5. The COB packaging device according to claim 4, characterized in that, The thickness of the light-transmitting adhesive layer (140) is less than the thickness of the wavelength conversion layer (130) covering the front side of the light-emitting chip (120).

6. The COB packaging device according to claim 1, 2 or 3, characterized in that, The wavelength conversion layer (130) covers only the front side of the plurality of light-emitting chips (120), and the light-transmitting adhesive layer (140) fills the receiving groove (112), covers the side side of the plurality of light-emitting chips (120), and covers the side and front side of the wavelength conversion layer (130).

7. The COB packaging device according to claim 6, characterized in that, The thickness of the wavelength conversion layer (130) is less than the thickness of the light-transmitting adhesive layer (140) covering the front side of the wavelength conversion layer (130).

8. A COB packaged device, characterized by, include: The substrate (110) is provided with a receiving groove (112); Multiple light-emitting chips (120) are spaced apart in the receiving groove (112); A first wavelength conversion layer (150) is provided only on the front side of the plurality of light-emitting chips (120); The second wavelength conversion layer (160) is disposed only on the front side of the first wavelength conversion layer (150); as well as A light-transmitting adhesive layer (140) fills the receiving groove (112), covers the side of the first wavelength conversion layer (150), and covers the front and side of the second wavelength conversion layer (160). The light-transmitting adhesive layer (140) is filled with scattering particles.

9. The COB packaging device according to claim 8, characterized in that, The thickness of the first wavelength conversion layer (150) and the thickness of the second wavelength conversion layer (160) are both less than the thickness of the light-transmitting adhesive layer (140) covering the front side of the second wavelength conversion layer (160).

10. The COB packaging device according to claim 8, characterized in that, The substrate (110) includes a base plate (114) and a dam (116) disposed on one side of the base plate (114), the dam (116) and the base plate (114) enclosing to form the receiving groove (112).

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