LED packaging structure and light-emitting device

Abstract

The invention relates to the technical field of semiconductor manufacturing, in particular to an LED packaging structure and a light-emitting device. The LED packaging structure comprises a substrate, a spacer layer located on the substrate, an IC chip, an LED chip and a light blocking layer. The light blocking layer covers one side, close to the packaging light emitting surface, of the IC chip, and the orthographic projection of the light blocking layer on the substrate is at least partially overlapped with the orthographic projection of the IC chip on the substrate; the light transmittance of the light blocking layer is lower than that of the substrate. Through the above design, the contrast of the packaging structure can be effectively improved, and the display effect is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to an LED packaging structure and a light-emitting device. Background Technology

[0002] In the display market, AMiP (Active Matrix Integrated Package) technology is one of the core development directions in the current LED display field. It marks a key leap for LED display technology towards high integration and high-pixel experience, and occupies an increasingly important position in the display market. This technology integrates the active driver IC and Micro LED into the same package, achieving a "lamp-driver integration" structural design. This not only significantly improves the pixel performance and display effect of the display, but also simplifies the subsequent assembly process, representing a significant breakthrough in driving the upgrade of LED display technology.

[0003] However, in the actual industrialization process of AMiP technology, the integrated packaging structure of active driver IC and Micro LED has the problem of poor contrast, which greatly affects the overall display effect when high pixel density is required. Summary of the Invention

[0004] This invention provides an LED packaging structure that can solve at least one problem in the background art to effectively improve the contrast of the integrated package of active driver IC and Micro LED, thereby improving the display effect.

[0005] This invention provides an LED packaging structure, including a substrate, a spacer layer, an IC chip, an LED chip, and a light-blocking layer; the spacer layer is located on the substrate; the LED chip is located on the side of the spacer layer opposite to the substrate; the IC chip is located on the side of the spacer layer opposite to the substrate and is spaced apart from the LED chip; the light-blocking layer is disposed between the substrate and the spacer layer; the orthographic projection of the light-blocking layer on the substrate at least partially overlaps with the orthographic projection of the IC chip on the substrate; the light transmittance of the light-blocking layer is lower than the light transmittance of the substrate.

[0006] This invention also provides a light-emitting device, including an LED packaging structure as described in the above embodiments.

[0007] The LED packaging structure provided by the present invention, by designing a light-blocking layer with low light transmittance between the spacer layer and the substrate, blocks the light reflected from the surface of the IC chip, reduces the visibility of the IC chip on the light-emitting side of the package, and thus effectively improves the contrast of the packaging structure and enhances the display effect.

[0008] Other features and beneficial effects of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figures 1-3 , Figures 5-8 These are cross-sectional schematic diagrams of the LED packaging structures provided in various embodiments of the present invention; Figure 4 yes Figure 3 A top view of the structure.

[0011] Figure label: 10. Substrate; 20. Spacer layer; 30. IC chip; 40. LED chip; 50. Light blocking layer; 51. Roughened structure; 60. Filler layer; 71. Wiring layer; 72. Pad; 80. Solder resist layer; 90. Adhesion layer; S. Encapsulation light-emitting surface. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings; the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0013] It should also be noted that the structural diagrams provided in the embodiments of the present invention are for the purpose of more clearly expressing the structural features of the LED packaging structure, but are not made to scale.

[0014] This invention provides an LED packaging structure, including: a substrate 10, a spacer layer 20, an LED chip 40, an IC chip 30, and a light-blocking layer 50; the spacer layer 20 is located on the substrate 10; the LED chip 40 is located on the side of the spacer layer 20 facing away from the substrate 10; the IC chip 30 is located on the side of the spacer layer 20 facing away from the substrate 10 and is spaced apart from the LED chip 40; the light-blocking layer 50 covers the side of the IC chip 30 near the light-emitting surface S of the package; the orthographic projection of the light-blocking layer 50 on the substrate 10 at least partially overlaps with the orthographic projection of the IC chip 30 on the substrate 10. Through this arrangement, the IC chip 30 can be effectively prevented from being observed from the side of the light-emitting surface S (i.e., the side of the substrate 10 facing away from the chip), thereby improving display contrast and optimizing the overall display effect.

[0015] In one embodiment, the light-blocking layer 50 comprises a black light-absorbing material.

[0016] In one embodiment, the thickness of the light-blocking layer 50 is less than the thickness of the spacer layer 20.

[0017] In one embodiment, the orthogonal projection of the IC chip 30 onto the substrate 10 falls within the orthogonal projection range of the light-blocking layer 50 onto the substrate 10, thereby achieving complete light shielding of the IC chip 30.

[0018] In one embodiment, the overlapping area of ​​the orthographic projection of the IC chip 30 on the substrate 10 and the orthographic projection of the light-blocking layer 50 on the substrate 10 accounts for more than 90% of the orthographic projection area of ​​the light-blocking layer 50 on the substrate 10; and the absolute value of the difference between the orthographic projection area of ​​the IC chip 30 on the substrate 10 and the orthographic projection area of ​​the light-blocking layer 50 on the substrate 10 is no more than 20% relative to the orthographic projection area of ​​the light-blocking layer 50 on the substrate 10. Through these limitations, effective light blocking can be achieved while minimizing the packaging space occupied by the light-blocking layer 50.

[0019] In one embodiment, the horizontal distance between the light-blocking layer 50 and the LED chip 40 is W1, and the horizontal distance between the IC chip 30 and the LED chip 40 is W2, wherein W1 ≥ 0.5W2, so as to avoid the light-blocking layer 50 blocking the light emission of the LED chip 40.

[0020] In one embodiment, the light-blocking layer 50 has an optical density value greater than or equal to 1 to ensure strong light-blocking performance.

[0021] In one embodiment, the absolute value of the vertical height difference H between the surface of the LED chip 40 facing away from the substrate 10 and the surface of the IC chip 30 facing away from the substrate 10 is no greater than 2 μm, so as to improve the mass transfer yield.

[0022] In one embodiment, the light-blocking layer 50 has a roughened structure 51 on the surface near the substrate 10 and / or on the surface away from the substrate 10, which effectively improves the adhesion to the spacer layer 20.

[0023] In one embodiment, the thickness of the IC chip 30 is between 10 μm and 20 μm; the thickness of the LED chip 40 is between 2 μm and 12 μm.

[0024] In one embodiment, a filler layer 60 is further included, located on the side of the spacer layer 20 opposite to the substrate 10, and at least covers a portion of the surface of the IC chip 30 and / or a portion of the surface of the LED chip 40.

[0025] In one embodiment, the filler layer 60 comprises a black light-absorbing material, or the material of the filler layer 60 comprises black silicone and / or black epoxy resin.

[0026] In one embodiment, the material of the filling layer 60 may be the same as or different from the material of the light-blocking layer 50.

[0027] In one embodiment, a wiring layer 71 is further included, which is located on the side of the LED chip 40 and the IC chip 30 away from the substrate 10, to electrically connect the IC chip 30 and the LED chip 40.

[0028] In one embodiment, the solder mask layer 80 and pads 72 are further included. The solder mask layer 80 covers a portion of the wiring layer 71 and at least covers a portion of the surface of the IC chip 30 and / or a portion of the surface of the LED chip 40. The pads 72 are in electrical contact with the wiring layer 71.

[0029] In one embodiment, the LED chip 40 includes one or more of red, blue, and green light chips, and the LED chip 40 and the IC chip 30 are transferred onto the substrate 10 via a mass transfer process.

[0030] In one embodiment, the spacer layer 20 includes a transfer layer made of a transparent material.

[0031] In one embodiment, the substrate 10 is a transparent substrate 10, and the light-blocking layer 50 is disposed between the substrate 10 and the spacer layer 20; the light transmittance of the light-blocking layer 50 is lower than the light transmittance of the substrate 10.

[0032] In one embodiment, an adhesion aid layer 90 is further included, which is located between the light-blocking layer 50 and the substrate 10 and / or between the light-blocking layer 50 and the spacer layer 20; the sum of the thicknesses of the adhesion aid layer 90 and the light-blocking layer 50 is less than the thickness of the spacer layer 20; by designing the adhesion aid layer 90, the adhesion to the spacer layer 20 or the substrate 10 can be effectively improved.

[0033] This invention also provides a light-emitting device, including an LED packaging structure as described in any of the above embodiments.

[0034] The technical solution of the present invention will now be described and explained in detail through various specific embodiments and accompanying drawings.

[0035] Example 1 Please see Figure 1 , Figure 1 This is a cross-sectional schematic diagram of an LED packaging structure provided in one embodiment of the present invention. The LED packaging structure provided in Embodiment 1 of the present invention includes at least a substrate 10, a spacer layer 20, an IC chip 30, an LED chip 40, and a light-blocking layer 50.

[0036] In this embodiment, the substrate 10 is located at the light-emitting position of the LED packaging structure. Therefore, the substrate 10 is preferably a transparent substrate to meet the light transmission requirements of the packaging structure. Specifically, the transmittance of the transparent substrate in the visible light band of 380nm~760nm is not less than 90%. The material of the transparent substrate can be flexibly selected according to the actual application scenario, including but not limited to sapphire, glass, epoxy, silicone, etc. Further, the thickness of the transparent substrate can be set to 50μm~200μm according to the structural strength requirements. For example, the thickness of the sapphire substrate can be selected from 50μm to 150μm to balance strength and lightweight, and the thickness of the glass substrate can be selected from 70μm to 200μm to balance light transmission and processability. Preferably, the side facing the spacer layer 20 can be plasma treated or coated (such as with a SiO2 thin film) to improve the interfacial adhesion with the spacer layer 20 and prevent delamination.

[0037] Spacer layer 20 is located on substrate 10. Spacer layer 20 may be made of insulating material, such as epoxy resin, silicone, polyimide (PI), silicon nitride (Si3N4), or silicon oxide (SiO2), to achieve electrical isolation between substrate 10 and upper-layer components. Bonding of spacer layer 20 to substrate 10 can be achieved through coating curing, sputtering deposition, or bonding processes. In this embodiment, spacer layer 20 preferably includes a transfer layer made of transparent material, serving as a substrate for mass transfer. This layer stably supports the LED chip 40 during mass transfer, preventing chip displacement or damage, and its transparency does not obstruct the light radiation path from the chip to the spacer layer 20 side, ensuring overall light extraction efficiency of the package. Of course, spacer layer 20 may also include other functional layer structures depending on actual needs; this embodiment does not limit this. As an example, the thickness of spacer layer 20 is between 1 μm and 4 μm.

[0038] LED chip 40 is located on the side of the spacer layer 20 facing away from the substrate 10. LED chip 40 includes one or more of red, blue, and green light chips, and is transferred onto the substrate 10 via a mass transfer process. As an example, the minimum dimension of one side of LED chip 40 is 1μm to 100μm. The thickness of LED chip 40 is between 2μm and 12μm, such as 2μm, 4μm, 5μm, 6μm, 8μm, 10μm, or 12μm; more preferably, it is less than 10μm.

[0039] The IC chip 30 is located on the side of the spacer layer 20 facing away from the substrate 10. The IC chip 30 internally incorporates a dedicated LED driving control circuit to drive and control the LED chip 40. The specific circuit design is tailored to actual needs and is not limited in this embodiment. The IC chip 30 is fixed to the surface of the spacer layer 20 by soldering or bonding with conductive adhesive. As an example, the minimum dimension of one side of the IC chip 30 is 1μm to 120μm, and the thickness of the IC chip 30 is between 10μm and 20μm, more preferably less than 12μm, such as 10μm, 11μm, or 12μm, specifically set according to actual functional requirements.

[0040] In this process, LED chip 40 and IC chip 30 are transferred from the wafer to the substrate 10 through mass transfer. The transfer order can be either sequential or simultaneous transfer of LED chip 40 and IC chip 30, depending on the actual requirements.

[0041] In existing technologies, LED packaging structures generally adopt an integrated architecture of "substrate-spacer-chip," where the LED chip and IC chip are directly co-mounted on the substrate surface through a spacer layer. While this architecture meets basic functional requirements in conventional display scenarios, it struggles to meet the stringent performance requirements of high-pixel-density high-end display applications. Therefore, to address this issue, research on packaging structures has revealed that, to ensure the light extraction efficiency and light transmittance of the LED chip, key layers such as the spacer layer in the packaging structure must be transparent layers made of highly transparent materials. However, the presence of these transparent layers makes the IC chip easily visible from the light-emitting surface S of the package, creating "dark spots" or "discoloration areas" unrelated to the displayed image. This disrupts the overall consistency of the display and significantly reduces the contrast ratio, failing to meet the demands of high-definition, high-contrast displays. Based on this, this embodiment, by adding a light-blocking layer 50, can achieve precise light-blocking of the IC chip 30 without changing the small-pitch integration size of the LED chip 40 and the IC chip 30 or sacrificing the light-emitting performance of the LED chip 40. This effectively prevents the IC chip 30 from being observed from the light-emitting surface, thereby improving display contrast and optimizing the overall display effect.

[0042] For details, please continue reading. Figure 1 The light-blocking layer 50 covers the side of the IC chip 30 near the light-emitting surface S of the package; the orthographic projection of the light-blocking layer 50 on the substrate 10 at least partially overlaps with the orthographic projection of the IC chip 30 on the substrate 10; that is, the projection area of ​​the light-blocking layer 50 and the projection area of ​​the IC chip 30 intersect.

[0043] In this embodiment, "encapsulated light-emitting surface S" refers to the main surface on which the light emitted by the LED chip 40 radiates outward after the LED encapsulation structure is assembled. Its specific location is determined by the hierarchical relationship of the encapsulation structure. For example, when a transparent substrate 10 is used as the supporting substrate for the entire structure, the spacer layer 20, LED chip 40, and IC chip 30 are all integrated on the same side of the substrate 10; wherein, the light-emitting direction of the LED chip 40 faces the substrate 10, therefore, "encapsulated light-emitting surface S" refers to the encapsulation surface on the side of the substrate 10 away from the chip (e.g., the encapsulation surface S). Figure 1 As shown in the diagram (S-surface), this surface is the viewing surface for the displayed image. In contrast, the side of the chip facing away from the substrate 10 is the "non-light-emitting surface," used only for circuit connections or heat dissipation and not involved in light radiation. In this case, the light-blocking layer 50 should be located between the IC chip 30 and the transparent substrate 10 to prevent the IC chip 30 from being observed through the transparent substrate 10 from the light-emitting surface S side of the package (i.e., the side of the substrate 10 facing away from the chip).

[0044] Preferably, the transmittance of the light-blocking layer 50 is lower than the transmittance of the transparent layer on the side of the light-emitting surface S. This ensures that the light-blocking layer 50 can effectively block the reflection of the IC chip 30 on the side of the light-emitting surface S, reducing the likelihood of the IC chip 30 being observed. For example, when the substrate 10 is a transparent substrate 10 and the light-emitting surface S is the surface closer to the substrate 10, the light-blocking layer 50 is disposed between the substrate 10 and the spacer layer 20; the transmittance of the light-blocking layer 50 is lower than the transmittance of the substrate 10, thereby reducing the degree to which the IC chip 30 is observed.

[0045] In this embodiment, "orthographic projection" refers to projecting the light-blocking layer 50 or IC chip 30 onto the contour area formed on the surface of the substrate 10 with the thickness direction of the substrate 10 as the projection direction or with the direction perpendicular to the upper / lower surface of the substrate 10 as the projection direction.

[0046] Please refer to Figure 5 "At least partially overlapping" can mean that the IC chip 30 partially overlaps on the edge near the LED chip 40. Since the edge area of ​​the IC chip 30 is easily affected by the light emitted by the LED chip 40, targeted light blocking is achieved by blocking the edge, while reducing the amount of material used in the light blocking layer 50.

[0047] Please see Figures 1-3 "At least partially overlapping" can also mean that the orthographic projection of the IC chip 30 on the substrate 10 falls within the orthographic projection range of the light-blocking layer 50 on the substrate 10. That is, the orthographic projection of the IC chip 30 is completely located within the orthographic projection range of the light-blocking layer 50. The two have an inclusive relationship, which can achieve complete light blocking of the IC chip 30 and is suitable for display scenarios with extremely high contrast requirements.

[0048] Please see Figure 6 , Figure 7 "At least partially overlapping" can also mean that the orthographic projection of the IC chip 30 on the substrate 10 completely overlaps with the orthographic projection of the light-blocking layer 50 on the substrate 10 and their areas are equal. That is, the orthographic projection area of ​​the light-blocking layer 50 and the orthographic projection area of ​​the IC chip 30 are exactly the same size and their projection outlines almost completely coincide. This design achieves full light blocking while minimizing the packaging space occupied by the light-blocking layer 50, making it suitable for small-pitch scenarios with limited packaging space.

[0049] Of course, due to process errors such as photolithography alignment deviation and thin film deposition uniformity deviation in semiconductor packaging processes, it is difficult to achieve complete overlap and absolute equality of the projections of the two in actual production. Based on this, this embodiment further limits the projection matching relationship between the IC chip 30 and the light-blocking layer 50. Specifically, the overlap area of ​​the orthographic projection of the IC chip 30 on the substrate 10 and the orthographic projection of the light-blocking layer 50 on the substrate 10 is greater than 90% of the orthographic projection area of ​​the light-blocking layer 50 on the substrate 10; and the absolute value of the difference between the orthographic projection area of ​​the IC chip 30 on the substrate 10 and the orthographic projection area of ​​the light-blocking layer 50 on the substrate 10 is no greater than 20% relative to the orthographic projection area of ​​the light-blocking layer 50 on the substrate 10, i.e., |S2-S1| / S2≤20%, where S1 is the orthographic projection area of ​​the IC chip 30 on the substrate 10 and S2 is the orthographic projection area of ​​the light-blocking layer 50 on the substrate 10. The above limitations take into account both the feasibility of the process implementation and the effective light-shielding effect of the light-blocking layer 50 on the IC chip 30, while avoiding the excessively large projected area of ​​the light-blocking layer 50 from occupying the packaging space, thus achieving a balance between light-shielding performance and packaging space utilization.

[0050] Preferably, please refer to Figure 4 The horizontal distance between the light-blocking layer 50 and the LED chip 40 is W1, and the horizontal distance between the IC chip 30 and the LED chip 40 is W2, wherein W1 ≥ 0.5W2.

[0051] In specific implementation, "horizontal spacing" refers to the shortest straight-line distance between the edges of two structures in a direction parallel to the surface of the substrate 10. W1 is the shortest horizontal distance between the edge of the light-blocking layer 50 near the LED chip 40 and the edge of the LED chip 40 near the light-blocking layer 50. W2 is the shortest horizontal distance between the edge of the IC chip 30 near the LED chip 40 and the edge of the LED chip 40 near the IC chip 30. In this embodiment, by designing W1≥0.5W2, the space for small-pitch packaging can be avoided, ensuring no physical overlap between the light-blocking layer 50 and the LED chip 40, and the spacing is sufficient to prevent the light-blocking layer 50 from blocking the light emission of the LED chip 40; at the same time, the light-blocking layer 50 can accurately block the IC chip 30, effectively improving the overall contrast of the LED packaging structure.

[0052] Furthermore, the light-blocking layer 50 can be obtained through photolithography patterning, which is a mature process in the semiconductor packaging field and is directly compatible with existing LED packaging production lines without the need for additional dedicated equipment.

[0053] Optionally, the light-blocking layer 50 includes a black light-absorbing material. Its function is to eliminate stray light entering the IC chip 30 and causing interference by absorbing light rather than reflecting it, thereby further reducing the visibility of the IC chip 30 from the light-emitting surface S of the package and improving the purity of the displayed image. The light-blocking layer 50 can be an insulating layer structure made of resin, photosensitive material, and solvent to prevent short circuits. Examples of black light-absorbing materials include black silicone (doped with titanium black) and black epoxy resin.

[0054] In this embodiment, the optical density (OD) value of the light-blocking layer 50 is preferably greater than or equal to 1, corresponding to a transmittance of less than or equal to 10%, which means it can block more than 90% of visible stray light, significantly reducing the visibility of the IC chip 30 from the light-emitting surface S of the package. If the optical density value is less than 1, it can only block less than 90% of stray light, and some light can still penetrate the light-blocking layer 50 and be observed from the light-emitting surface S of the package, failing to solve the problem of insufficient contrast under high pixel density. More preferably, the optical density value is greater than or equal to 2, with a corresponding transmittance ≤ 1%. That is, the light absorption rate of the LED chip 40 in the emission band is greater than or equal to 95%. Even more preferably, the optical density value of the light-blocking layer 50 is between 1 and 3.

[0055] Optionally, the thickness of the light-blocking layer 50 is less than the thickness of the spacer layer 20. In practice, if the light-blocking layer 50 is too thick, it will not only affect the circuit layout but also increase the height difference between the LED chip 40 and the IC chip 30, thus affecting the mass transfer yield. Therefore, this embodiment effectively avoids the above problems by limiting the thickness of the light-blocking layer 50 to be thinner than the thickness of the spacer layer 20. Furthermore, while ensuring light absorption, a thinner layer improves the yield of mass transfer and the manufacturing process.

[0056] In particular, please see Figure 3 In this embodiment, the absolute value of the vertical height difference H between the surface of the LED chip 40 facing away from the substrate 10 and the surface of the IC chip 30 facing away from the substrate 10 is preferably no greater than 2 μm. Specifically, the thickness of the light-blocking layer 50 can be adjusted to ensure that the absolute value of the vertical height difference H is no greater than 2 μm, which is beneficial to significantly improve the mass transfer yield and avoids a large difference between the two that would affect the process. In this embodiment, the vertical height difference H is preferably 0 μm, that is, the heights of the LED chip 40 and the IC chip 30 are flush.

[0057] In one embodiment, please refer to Figure 2 The light-blocking layer 50 has a roughened structure 51 on the surface near the substrate 10 and / or on the surface away from the substrate 10.

[0058] In practice, the surface of the light-blocking layer 50 can be roughened in a regular or irregular manner by dry or wet etching to form a roughened structure 51. This design can effectively improve the bonding with the spacer layer 20, help enhance the stability of product use, and thus improve the service life of the packaging structure.

[0059] In another embodiment, please refer to Figure 7 , Figure 8 The LED packaging structure also includes an adhesion aid layer 90, which is located between the light-blocking layer 50 and the substrate 10 and / or between the light-blocking layer 50 and the spacer layer 20; the sum of the thicknesses of the adhesion aid layer 90 and the light-blocking layer 50 is less than the thickness of the spacer layer 20.

[0060] In specific implementation, this embodiment can improve the adhesion to the substrate 10 or transfer layer by designing an adhesion promoter 90 between the light-blocking layer 50 and the substrate 10 and / or between the light-blocking layer 50 and the spacer layer 20, thus preventing the light-blocking layer 50 from detaching or warping. The material of the adhesion promoter 90 must simultaneously meet the requirements of high adhesion and not affect the light-shielding performance of the light-blocking layer 50 and the light-transmitting performance of the spacer layer 20. For example, the material of the adhesion promoter 90 can be an organic photoresist or an inorganic metal thin film. Based on this, this embodiment preferably has a sum of thicknesses of the adhesion promoter 90 and the light-blocking layer 50 that is less than the thickness of the spacer layer 20. This not only avoids encroaching on packaging space and ensures that the light-blocking layer 50 and the adhesion promoter 90 are integrally embedded in the predetermined area of ​​the spacer layer 20 without affecting the small-pitch integration of the chip, but also further guarantees the yield of mass transfer.

[0061] In other embodiments, the LED package structure further includes a filler layer 60 located on the side of the spacer layer 20 away from the substrate 10, and at least covering a portion of the surface of the IC chip 30 and / or a portion of the surface of the LED chip 40.

[0062] Specifically, the filler layer 60 is disposed on the side of the spacer layer 20 away from the substrate 10, either by completely covering or selectively covering it. The coverage area may include at least a portion of the surface of the IC chip 30 (e.g., at least a portion of the top surface and / or at least a portion of the sidewalls of the IC chip 30), or at least a portion of the surface of the LED chip 40 (e.g., at least a portion of the top surface and / or at least a portion of the sidewalls of the LED chip 40). It may also cover exposed areas on the spacer layer 20 not occupied by the chip, thereby forming an effective protective interface to achieve electrical isolation, prevent external moisture and dust from intruding, and protect the chip. Furthermore, the filler layer 60 can be applied around the LED chip 40 and the IC chip 30 using methods such as photolithography patterning and dry etching.

[0063] The filler layer 60 can be made of organic insulating materials, such as transparent polyimide (PI), epoxy-modified acrylic resin, or silicone; it can also be made of inorganic insulating materials, such as silicon nitride (Si3N4), silicon oxide (SiO2), or aluminum oxide (Al2O3); or it can be made of composite insulating materials. The specific materials and coverage thickness can be reasonably designed according to actual protection requirements. This embodiment does not limit this. In this embodiment, the filler layer 60 preferably includes a black light-absorbing material to avoid stray light inside the package structure from being reflected and scattered between the LED chip 40 and the IC chip 30, thus preventing cross-light interference. At the same time, it can further shield the area of ​​the IC chip 30 not covered by the light-blocking layer 50, eliminating the potential for the edge outline of the IC chip 30 to be observed from the light-emitting surface S of the package. The black light-absorbing material or the filler layer 60 material includes black silicone, black epoxy resin, black phosphor conversion adhesive, or a combination thereof. In this embodiment, the material of the filler layer 60 and the material of the light-blocking layer 50 can be the same or different. When the two materials are the same, the light-blocking layer 50 and the filling layer 60 can be integrated to block light, which can avoid the problem of stray light leakage caused by the difference in optical properties of the two materials and ensure full-dimensional light blocking from the bottom to the top of the IC chip 30.

[0064] Furthermore, the LED package structure also includes a wiring layer 71 (RDL), which is located on the side of the LED chip 40 and the IC chip 30 away from the substrate 10, to electrically connect the IC chip 30 and the LED chip 40. That is, according to actual needs, the wiring layer 71 is designed on the non-light-emitting side of the package structure to avoid affecting light emission. The wiring layer 71 can be made of a metal material to obtain specifically designed lines through sputtering, evaporation, electroplating, etc., to connect the electrodes of the LED chip 40 and the pins of the IC chip 30.

[0065] Furthermore, the LED packaging structure also includes a solder resist layer 80 and pads 72, wherein the solder resist layer 80 covers a portion of the wiring layer 71 and at least covers a portion of the surface of the IC chip 30 and / or a portion of the surface of the LED chip 40.

[0066] In practice, the solder resist layer 80 is applied to the surface of the aforementioned structure using methods such as photolithography patterning, vapor deposition, dry etching, and wet etching to prevent flux, such as solder paste, from seeping into the package and causing product failure during die bonding. The solder resist layer 80 can be made from chemical substances such as ink through photolithography patterning, or from inorganic materials such as silicon oxide through vapor deposition and etching.

[0067] The pad 72 is in electrical contact with the wiring layer 71 to achieve electrical connection between the external circuitry and the LED package structure. The pad 72 can be fabricated using chemical vapor deposition, and its material is generally metal.

[0068] Example 2 Based on the above, Embodiment 3 of the present invention also provides a light-emitting device, which adopts the LED packaging structure described in the above embodiments to effectively improve the contrast of the device and enhance the display effect.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An LED packaging structure, characterized in that, include: Substrate; A spacer layer is located on the substrate; The LED chip is located on the side of the spacer layer opposite to the substrate; The IC chip is located on the side of the spacer layer away from the substrate and is spaced apart from the LED chip; A light-blocking layer covers the side of the IC chip near the light-emitting surface of the package. The orthographic projection of the light-blocking layer on the substrate at least partially overlaps with the orthographic projection of the IC chip on the substrate.

2. The LED packaging structure according to claim 1, characterized in that: The light-blocking layer comprises a black light-absorbing material.

3. The LED packaging structure according to claim 1, characterized in that: The thickness of the light-blocking layer is less than the thickness of the spacer layer.

4. The LED packaging structure according to claim 1, characterized in that: The orthogonal projection of the IC chip on the substrate falls within the orthogonal projection range of the light-blocking layer on the substrate.

5. The LED packaging structure according to claim 1, characterized in that: The overlapping area of ​​the orthographic projection of the IC chip on the substrate and the orthographic projection of the light-blocking layer on the substrate accounts for more than 90% of the orthographic projection area of ​​the light-blocking layer on the substrate; and the absolute value of the difference between the orthographic projection area of ​​the IC chip on the substrate and the orthographic projection area of ​​the light-blocking layer on the substrate is no more than 20% relative to the orthographic projection area of ​​the light-blocking layer on the substrate.

6. The LED packaging structure according to claim 1, characterized in that: The horizontal distance between the light-blocking layer and the LED chip is W1, and the horizontal distance between the IC chip and the LED chip is W2, wherein W1 ≥ 0.5W2.

7. The LED packaging structure according to claim 1, characterized in that: The optical density value of the light-blocking layer is greater than or equal to 1.

8. The LED packaging structure according to claim 1, characterized in that: The absolute value of the vertical height difference H between the surface of the LED chip facing away from the substrate and the surface of the IC chip facing away from the substrate is no greater than 2 μm.

9. The LED packaging structure according to claim 1, characterized in that: The light-blocking layer has a roughened structure on the surface near the substrate and / or on the surface away from the substrate.

10. The LED packaging structure according to claim 1, characterized in that: The thickness of the IC chip is between 10μm and 20μm; the thickness of the LED chip is between 2μm and 12μm.

11. The LED packaging structure according to claim 1, characterized in that: It also includes a filler layer located on the side of the spacer layer opposite to the substrate, and at least covering a portion of the surface of the IC chip and / or a portion of the surface of the LED chip.

12. The LED packaging structure according to claim 11, characterized in that: The filler layer comprises a black light-absorbing material, or the filler layer comprises black silicone and / or black epoxy resin.

13. The LED packaging structure according to claim 11, characterized in that: The material of the filling layer may be the same as or different from the material of the light-blocking layer.

14. The LED packaging structure according to claim 1, characterized in that: It also includes a wiring layer located on the side of the LED chip and the IC chip away from the substrate, for electrically connecting the IC chip and the LED chip.

15. The LED packaging structure according to claim 14, characterized in that: It also includes a solder resist layer and pads, the solder resist layer covering a portion of the wiring layer, and at least covering a portion of the surface of the IC chip and / or a portion of the surface of the LED chip; the pads are in electrical contact with the wiring layer.

16. The LED packaging structure according to claim 1, characterized in that: The LED chip includes one or more of red, blue, and green chips, and the LED chip and the IC chip are transferred onto the substrate via a mass transfer process.

17. The LED packaging structure according to claim 1, characterized in that: The spacer layer includes a transfer layer made of a transparent material.

18. The LED packaging structure according to claim 1, characterized in that: The substrate is a transparent substrate, and the light-blocking layer is disposed between the substrate and the spacer layer; the light transmittance of the light-blocking layer is lower than the light transmittance of the substrate.

19. The LED packaging structure according to claim 18, characterized in that: It also includes an adhesion-enhancing layer, which is located between the light-blocking layer and the substrate and / or between the light-blocking layer and the spacer layer; the sum of the thicknesses of the adhesion-enhancing layer and the light-blocking layer is less than the thickness of the spacer layer.

20. A light-emitting device, characterized in that: This includes using the LED packaging structure as described in any one of claims 1 to 19.

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