Packaging protection structure of optical chip photosensitive area

Abstract

The utility model discloses a packaging protection structure of a photosensitive area of an optical chip, which comprises the optical chip and a substrate, the substrate is provided with a light hole with the aperture consistent with the diameter of the photosensitive area of the optical chip, the optical chip is arranged at the bottom of the substrate, the photosensitive area of the optical chip is positioned at the orifice of the light hole, the light hole is filled with a transparent body, and the optical chip is arranged below the substrate. And the sealing glue layer is used for packaging the optical chip and a welding ball I arranged between the optical chip and the substrate by sealing glue. The utility model has the advantages that: the transparent body is neat and non-warped, the surface is smooth and traceless, the incident light is uniform, and scattered refraction is avoided; the structure is simple and practicability is high.

Description

Technical Field

[0001] The utility model relates to a packaging protection structure for a photosensitive area of ​​an optical chip, belonging to the technical field of chip packaging. Background Art

[0002] With the continuous development of chip technology, there are more and more high-pixel camera module products. The current packaging technology cannot meet the process requirements of current high-end imaging products in terms of the height of the camera module and the flatness of the optical performance. At the same time, during the packaging process, the different thermal expansion coefficients during the heating and curing process cause the chip to deform, reducing reliability.

[0003] Existing technology involves creating a photosensitive area on the surface of an optical chip, placing glass on top, and then using plastic molding compound for open-molding packaging. This not only requires a lot of glue and is costly, but also creates surface unevenness between the chip and glass, impacting optical reflection and refraction. Different mechanical stresses and thermal expansion coefficients can also lead to warping during the packaging process. Furthermore, after plastic molding, the surface needs to be polished and flattened, which can damage the glass coating and even scratch the glass, affecting light transmission.

[0004] Patent document No. 202310801893.9 discloses an LED chip packaging structure and a method for preparing the same, relating to the field of chip packaging technology. The LED chip packaging structure utilizes a light-blocking layer to cover a plurality of pixel LED chips, wherein the light-emitting side of the pixel LED chip is exposed on one side of the light-blocking layer, and a redistribution layer is provided on the other side of the light-blocking layer, wherein the light-blocking layer is used to block crosstalk between adjacent pixel LED chips. Compared to the prior art, the present invention utilizes an opaque light-blocking layer to cover the periphery of the pixel LED chip. When actually emitting light, the light-blocking layer can play a side shading role, blocking crosstalk between adjacent pixel LED chips and improving the brightness and uniformity of the light.

[0005] The technical solution provided by this patent replaces the substrate structure in conventional technology by re-setting the circuit distribution layer and the solder mask layer, and by setting a blocking light-shielding layer with a certain thickness on the periphery of the LED chip. The blocking light-shielding layer forms a hole in the photosensitive area on the front of the LED chip, and a transparent body is filled in the hole. Although this can block the crosstalk between adjacent pixel LED chips and improve the brightness and uniformity of the light, the process of re-routing the circuit and setting the solder mask layer is extremely complicated. Coupled with the subsequent packaging structure (setting a blocking light-shielding layer with a certain thickness on the periphery of the LED chip, the blocking light-shielding layer forms a hole in the photosensitive area on the front of the LED chip, and a transparent body is filled in the hole), the application difficulty of this technical solution is further increased. Utility Model Content

[0006] The technical problem to be solved by the utility model is: how to form a regular, clean and transparent body in the photosensitive area on the surface of the optical chip in a simple way.

[0007] In view of the above problems, the technical solutions proposed by the present invention are:

[0008] A packaging and protection structure for the photosensitive area of ​​an optical chip includes an optical chip and a substrate. A light-transmitting hole with an aperture consistent with the diameter of the photosensitive area of ​​the optical chip is provided on the substrate. The optical chip is mounted on the bottom of the substrate, with its photosensitive area located at the opening of the light-transmitting hole. A transparent body is filled in the light-transmitting hole. Below the substrate, there is a sealing layer that uses sealing glue to encapsulate the optical chip and the welding balls between it and the substrate.

[0009] The upper end surface of the transparent body is a plane parallel to the upper surface of the photosensitive area of ​​the optical chip.

[0010] The upper end surface of the transparent body is lower than the upper surface of the substrate.

[0011] The height difference between the upper end surface of the transparent body and the upper surface of the substrate is 0.05-0.15 mm.

[0012] The transparent body is a gel solidified body, and the bottom of the transparent body is bonded to the photosensitive area of ​​the optical chip.

[0013] The second welding ball arranged under the substrate is located outside the sealing layer. Beneficial effects

[0014] 1. Ensure that the transparent body is regular without warping, the surface is smooth and without marks, and the light enters evenly without scattered refraction;

[0015] 2. The optical chip is reverse mounted to avoid wiring on the chip surface, which can reduce the package height and thus reduce the total thickness of the chip;

[0016] 3. Simple structure and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic cross-sectional view of the optical chip to be packaged;

[0018] Figure 2 Schematic diagram of the cross section of the optical chip after packaging.

[0019] In the figure: 1, substrate; 101, light-transmitting hole; 2, optical chip; 201, photosensitive area; 3, solder ball 1; 4, solder ball 2; 5, transparent body; 6, sealing layer; DETAILED DESCRIPTION

[0020] The present invention will be further described below with reference to the accompanying drawings:

[0021] like Figure 1 、 2 As shown, a packaging and protection structure for the photosensitive area of ​​an optical chip includes an optical chip 2 and a substrate 1. A light-transmitting hole 101 having an aperture diameter consistent with that of the photosensitive area 201 of the optical chip 2 is provided on the substrate 1. The optical chip 2 is mounted on the bottom of the substrate 1, with its photosensitive area 201 located at the opening of the light-transmitting hole 101. The light-transmitting hole 101 is filled with a transparent body 5. Below the substrate 1, a sealing layer 6 is provided, which uses a sealing glue to seal the optical chip 2 and the solder balls 3 between the optical chip 2 and the substrate 1. Thus, when sealing the solder balls 3 and the optical chip, the sealing is performed on the lower surface of the substrate 1 instead of the previous sealing on the upper surface of the substrate 1. Therefore, deep polishing of the upper surface of the substrate 1 is not required in the later stage, and the upper surface of the transparent body 5 in the light-transmitting hole 101 is not damaged. Light can be normally transmitted through the transparent body 5 to the photosensitive area of ​​the optical chip 2.

[0022] The upper end surface of the transparent body 5 is a plane parallel to the upper surface of the photosensitive area 201 of the optical chip 2, so that it can ensure that the light can pass through the transparent body 5 evenly and parallelly, avoiding astigmatism and refraction.

[0023] The upper end surface of the transparent body 5 is lower than the upper surface of the substrate 1, thereby preventing the upper surface of the substrate from being scratched when cleaning.

[0024] Preferably, the height difference between the upper end surface of the transparent body 5 and the upper surface of the substrate 1 is 0.05-0.15 mm, such as 0.05 mm, 0.1 mm, or 0.15 mm.

[0025] The transparent body 5 is a solidified body of glue, and its bottom is bonded to the photosensitive area 201 of the optical chip 2, so as to prevent other media from entering between the transparent body 5 and the photosensitive area 201 of the optical chip 2, causing scattered refraction when light passes through.

[0026] The welding balls 4 provided under the substrate 1 are located outside the sealing layer 6 to ensure that welding connections can be implemented with other units.

[0027] The above embodiments are only used to more clearly describe the present invention and cannot be regarded as limiting the scope of protection covered by the present invention. Any modifications in equivalent forms should be regarded as falling within the scope of protection covered by the present invention.

Claims

1. A packaging protection structure for a photosensitive area of ​​an optical chip, comprising an optical chip (2) and a substrate (1), characterized in that: A light-transmitting hole (101) having an aperture diameter consistent with the diameter of a photosensitive area (201) of an optical chip (2) is provided on a substrate (1). The optical chip (2) is mounted on the bottom of the substrate (1), with its photosensitive area (201) located at the opening of the light-transmitting hole (101). A transparent body (5) is filled in the light-transmitting hole (101). Below the substrate (1), there is a sealing layer (6) formed by sealing the optical chip (2) and a welding ball (3) between the optical chip (2) and the substrate (1).

2. The packaging and protection structure for the photosensitive area of ​​an optical chip according to claim 1, wherein: The upper end surface of the transparent body (5) is a plane parallel to the upper surface of the photosensitive area (201) of the optical chip (2).

3. The packaging and protection structure for the photosensitive area of ​​an optical chip according to claim 2, wherein: The upper end surface of the transparent body (5) is lower than the upper surface of the substrate (1).

4. The packaging and protection structure for the photosensitive area of ​​an optical chip according to claim 3, wherein: The height difference between the upper end surface of the transparent body (5) and the upper surface of the substrate (1) is 0.05-0.15 mm.

5. The packaging and protection structure for the photosensitive area of ​​an optical chip according to claim 1, wherein: The transparent body (5) is a gel-solidified body, the bottom of which is bonded to the photosensitive area (201) of the optical chip (2).

6. The packaging and protection structure for the photosensitive area of ​​an optical chip according to claim 1, characterized in that: The second welding ball (4) provided under the substrate (1) is located outside the sealing layer (6).

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