Image sensor integrated antenna packaging structure and packaging method

Abstract

The present invention discloses an image sensor integrated antenna packaging structure and packaging method; the packaging structure includes a carrier board and a chip, the front of the chip has a photosensitive area and a non-photosensitive area, and a PAD is provided on the non-photosensitive area; the front of the chip is bonded to the carrier board; a through hole corresponding to the position of the non-photosensitive area of ​​the chip is provided on the carrier board, and a conductive metal is filled in the through hole; a metal light shielding layer corresponding to the position of the through hole is provided on the upper and lower surfaces of the carrier board; the metal light shielding layer on the lower surface of the carrier board is used to connect the antenna; a metal barrier layer corresponding to the position of the photosensitive area is provided on the back of the chip, and a conductive composite structure electrically connected to the PAD is formed on the chip. The present invention not only improves the optical effect of the image sensor, but also integrates the antenna function on the image sensor chip, so that the antenna structure becomes miniaturized, and at the same time enables the image sensor chip to realize the information transmission function.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging, and in particular to an image sensor integrated antenna packaging structure and a packaging method. Background Art

[0002] With the widespread application of image sensors in the consumer, security and automotive fields, users have put forward higher requirements for their image sensing effects; however, many image sensor chips now have some optical imaging problems when imaging, such as glare and ghosting. As high-end electronics develop towards high speed and miniaturization, the semiconductor industry has higher requirements for high product integration. For example, some integrated structures integrate image sensor chips with computing chips and storage chips to realize signal calculation and storage.

[0003] Traditional antennas are usually assembled on a PCB board with other chips in the form of antenna chips. The packaging volume, area and power consumption are large, which is not conducive to miniaturization and high efficiency. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide an image sensor integrated antenna packaging structure and packaging method. The present invention not only improves the optical effect of the image sensor, but also integrates the antenna function on the image sensor chip, making the antenna structure miniaturized, and at the same time enables the image sensor chip to realize the information transmission function.

[0005] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0006] An image sensor integrated antenna packaging structure comprises a carrier board and a chip, wherein the front side of the chip has a photosensitive area and a non-photosensitive area, and a PAD and a signal conversion circuit are arranged on the non-photosensitive area; the front side of the chip is bonded to the carrier board; a through hole corresponding to the position of the non-photosensitive area of ​​the chip is arranged on the carrier board; the through hole is filled with conductive metal; metal light shielding layers corresponding to the position of the through hole are arranged on the upper and lower surfaces of the carrier board; the metal light shielding layer on the lower surface of the carrier board is used for connecting the antenna; a metal barrier layer corresponding to the position of the photosensitive area is arranged on the back side of the chip, and a conductive composite structure electrically connected to the PAD is formed on the chip.

[0007] Furthermore, the bonding structure between the carrier and the chip is a cavity bonding structure or a cavity-free bonding structure; and when the bonding structure between the carrier and the chip is a cavity bonding structure, the cavity bonding structure has a cofferdam cavity corresponding to the photosensitive area of ​​the chip.

[0008] Furthermore, the width of the cofferdam cavity is equal to or greater than the width of the photosensitive area of ​​the chip.

[0009] Furthermore, a through hole corresponding to the position of the PAD is provided on the chip; the conductive composite structure includes a metal redistribution layer and a signal lead-out structure; an insulating layer is formed on the back side of the chip, and the insulating layer extends to cover the hole wall of the through hole of the chip; a metal redistribution layer electrically connected to the PAD of the chip is formed on the insulating layer; a solder resist layer is formed on the metal redistribution layer, an opening is formed on the solder resist layer, and a signal lead-out structure electrically connected to the metal redistribution layer is formed at the opening of the solder resist layer.

[0010] Furthermore, an opening is formed on the insulating layer to electrically connect the metal barrier layer to the metal redistribution layer.

[0011] The present invention further provides a packaging method for an image sensor integrated antenna packaging structure, comprising the following steps:

[0012] S1, providing a carrier and a chip wafer, wherein the front side of the chip wafer has a photosensitive area and a non-photosensitive area, and a PAD and a chip conversion circuit are provided on the non-photosensitive area, and determining the portion of the carrier corresponding to the non-photosensitive area of ​​the chip wafer after bonding with the chip wafer;

[0013] S2, forming a through hole at the portion of the determined carrier corresponding to the non-photosensitive area of ​​the chip wafer, and forming a metal light shielding layer on the upper and lower surfaces of the portion; the metal light shielding layer on the lower surface of the carrier is used to connect the antenna;

[0014] S3, bonding the front side of the chip wafer to the upper surface of the carrier;

[0015] S4, forming a metal barrier layer at a position corresponding to the photosensitive area on the back side of the chip wafer;

[0016] S5, forming a conductive composite structure on the chip wafer that is electrically connected to the PAD of the chip wafer.

[0017] S6, cutting the obtained structure into an image sensor integrated antenna packaging structure containing a single chip.

[0018] Wherein, the carrier plate is made of a transparent material, preferably glass.

[0019] Furthermore, the carrier board and the chip wafer are bonded together by bonding glue.

[0020] Furthermore, the bonding adhesive is a high-transmittance material, preferably epoxy resin.

[0021] Furthermore, the bonding structure between the carrier and the chip wafer is a bonding structure with a cavity or a bonding structure without a cavity. When the bonding structure between the carrier and the chip wafer is a bonding structure with a cavity, the bonding structure with a cavity has a cofferdam cavity corresponding to the photosensitive area of ​​the chip wafer.

[0022] Furthermore, the width of the cofferdam cavity is equal to or greater than the width of the corresponding photosensitive area of ​​the chip wafer.

[0023] Furthermore, the conductive composite structure in step S5 includes a metal redistribution layer and a signal derivation structure; the formation process of the conductive composite structure is:

[0024] S51, forming a through hole at a position of the chip wafer corresponding to the PAD, and forming an insulating layer on the upper surface of the chip wafer, wherein the insulating layer extends and covers the hole wall of the through hole;

[0025] S52, forming a metal redistribution layer electrically connected to the PAD of the chip wafer on the insulating layer;

[0026] S53, forming a solder resist layer on the metal redistribution layer, forming an opening in the solder resist layer, and then forming a signal derivation structure electrically connected to the metal redistribution layer at the opening of the solder resist layer.

[0027] Furthermore, an opening is formed on the insulating layer to electrically connect the metal barrier layer to the metal redistribution layer.

[0028] Furthermore, the signal derivation structure is a solder ball.

[0029] The beneficial effects of the present invention are:

[0030] The present invention introduces a metal barrier layer on the back side of the photosensitive area of ​​the chip wafer to block infrared light, and sets a metal light-shielding layer on the non-photosensitive area on the front side of the chip wafer to block reflected light, thereby effectively improving the optical effect of the image sensor; and the present invention integrates an antenna function on the image sensor chip, so that the antenna structure becomes miniaturized, and at the same time enables the image sensor chip to realize the information transmission function. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure obtained in step S2 of the packaging method in an embodiment of the present invention.

[0032] Figure 2 It is a schematic diagram of the structure obtained in step S3 of the packaging method in an embodiment of the present invention.

[0033] Figure 3 It is a schematic diagram of the structure obtained in step S4 of the packaging method in an embodiment of the present invention.

[0034] Figure 4 It is a schematic diagram of the structure obtained in step S51 in the packaging method of an embodiment of the present invention.

[0035] Figure 5 It is a schematic diagram of the structure obtained in step S52 in the packaging method of an embodiment of the present invention.

[0036] Figure 6 It is a schematic diagram of the structure obtained in step S53 in the packaging method of an embodiment of the present invention.

[0037] Figure 7 This is a schematic diagram of a structure obtained in another embodiment of step S3 in the packaging method of the present invention. DETAILED DESCRIPTION

[0038] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0039] like Figures 1 to 6 A preferred embodiment of a packaging method of an image sensor integrated antenna packaging structure shown includes the following steps:

[0040] S1, provide a carrier board 1 and a chip wafer 2, the front side of the chip wafer 2 has a photosensitive area 21 and a non-photosensitive area, the non-photosensitive area is provided with a PAD 22 and a signal conversion circuit, and determine the portion of the carrier board 1 corresponding to the non-photosensitive area of ​​the chip wafer 2 after the carrier board 1 is bonded to the chip wafer 2; wherein the carrier board 1 is a transparent material, and in the present embodiment, the carrier board is glass.

[0041] S2, forming a through hole by etching process at the non-photosensitive area of ​​the chip wafer 2 of the determined carrier 1; filling the through hole with conductive metal; and forming a metal light shielding layer 3 on the upper and lower surfaces of the determined part by coating process, so as to obtain Figure 1 The structure shown; the metal light shielding layer 3 on the lower surface of the carrier board 1 is used to connect the antenna.

[0042] S3, bonding the front side of the chip wafer 2 to the upper surface of the carrier board 1 through a bonding adhesive layer 4 formed by bonding adhesive, and obtaining Figure 2 The structure shown;

[0043] The bonding glue is a high-transmittance material. In this embodiment, the bonding glue is preferably epoxy resin;

[0044] The bonding structure between the carrier 1 and the chip wafer 2 can be a cavity bonding structure or a cavity-free bonding structure; in this preferred embodiment, Figure 2 The bonding structure in is a cavity bonding structure, which has a cofferdam cavity 5 corresponding to the photosensitive area of ​​the chip wafer; specifically, the cofferdam cavity 5 is surrounded by a bonding adhesive layer;

[0045] The width of the cofferdam cavity 5 may be equal to or greater than the width of the corresponding photosensitive area of ​​the chip wafer 2; the width of the bonding adhesive layer 4 may be less than or close to the width of the metal light shielding layer 3 thereunder; the cofferdam cavity 5 may be used to improve the glare problem caused by the light reflection phenomenon formed by the overflow of the bonding adhesive;

[0046] In other embodiments, the bonding structure between the carrier 1 and the chip wafer 2 can be as follows: Figure 7 The cavity-free bonding structure formed by bonding glue is shown.

[0047] S4, thinning the back side of the chip wafer 2, and then forming a metal barrier layer 6 at the position of the back side of the chip wafer 2 corresponding to the photosensitive area, to obtain Figure 3 The structure shown;

[0048] The metal barrier layer 6 is prepared by metal sputtering and etching processes; the material of the metal barrier layer 6 is aluminum or copper; the width of the metal barrier layer 6 is greater than the width of the photosensitive area to block the infrared light on the back of the photosensitive area.

[0049] S5, forming a conductive composite structure electrically connected to the PAD of the chip wafer on the chip wafer 2; including a metal redistribution layer 7 and a signal derivation structure 8; the formation process of the conductive composite structure is:

[0050] S51, forming a through hole 23 at a position corresponding to the PAD 22 of the chip wafer 2 by an etching process, and forming an insulating layer 9 on the upper surface of the chip wafer 2 by a chemical vapor deposition method, wherein the insulating layer 9 extends and covers the hole wall of the through hole 23, and the Figure 4 The structure shown;

[0051] The through hole 23 of the chip wafer 2 may be a straight hole, an inclined hole or a second-order inclined hole; in this embodiment, the through hole of the chip wafer 2 is a straight hole;

[0052] When the through hole is a straight hole or a single oblique hole structure, the material of the insulating layer 9 is generally silicon oxide; when the through hole is a second-order oblique hole structure, the material of the insulating layer 9 can be silicon oxide or epoxy resin;

[0053] In addition, this step also makes an opening at a specified position of the insulating layer 9 so that the metal barrier layer 6 is connected to the ground wire to shield the information of the external magnetic field. It can also serve as the ground wire of the antenna structure and the reflection plane. When the material of the insulating layer 9 is silicon oxide, the opening can be made by photolithography and oxidation etching. When the material of the insulating layer 9 is silicon oxide or epoxy resin, the opening can be made directly by photolithography process.

[0054] S52, forming a metal redistribution layer 7 electrically connected to the PAD of the chip wafer 2 on the insulating layer 9, and obtaining Figure 5 The structure shown.

[0055] S53, forming a solder resist layer 10 on the metal redistribution layer 7, forming an opening on the solder resist layer 10, and then forming a signal derivation structure 8 electrically connected to the metal redistribution layer 7 at the opening of the solder resist layer 10, so as to obtain Figure 6Structure shown; in this embodiment, the signal export structure 8 is a solder ball.

[0056] S6, cutting the obtained structure into an image sensor integrated antenna packaging structure containing a single chip.

[0057] After packaging is completed, the metal light shielding layer 3 on the lower surface of the carrier 1 can be connected to the antenna, and the metal barrier layer 6 can be connected to the metal wiring layer 7 through the opening on the insulating layer 9, thereby achieving connection with the ground wire.

[0058] like Figure 6 The preferred embodiment of the image sensor integrated antenna packaging structure shown in the figure comprises a carrier board 1 and a chip cut from a chip wafer 2, the front side of the chip has a photosensitive area 21 and a non-photosensitive area, and a PAD 22 and a signal conversion circuit are arranged on the non-photosensitive area. The signal conversion circuit is used to realize the conversion operation of optical signals and electrical signals. The front side of the chip is bonded to the carrier board 1; the bonding structure between the carrier board 1 and the chip is a cavity bonding structure; the cavity bonding structure has a cofferdam cavity 5 corresponding to the photosensitive area 21 of the chip; the width of the cofferdam cavity 5 is greater than the width of the photosensitive area 21 of the chip. The carrier board 1 is provided with a through hole corresponding to the position of the non-photosensitive area of ​​the chip, and the through hole is filled with conductive metal; the upper and lower surfaces of the carrier board 1 are provided with a metal light shielding layer 3 corresponding to the position of the through hole; the metal light shielding layer 3 on the lower surface of the carrier board 1 is used to connect the antenna. The back side of the chip is provided with a metal barrier layer 6 corresponding to the position of the photosensitive area 21. The width of the metal barrier layer 6 is greater than the width of the photosensitive area 21 to block the infrared light on the back of the photosensitive area. A through hole 23 corresponding to the position of the PAD 22 is provided on the chip; a conductive composite structure electrically connected to the PAD 22 is formed on the chip. The conductive composite structure includes a metal redistribution layer and a signal derivation structure; an insulating layer 9 is formed on the back of the chip, and the insulating layer 9 extends and covers the hole wall of the through hole 23 of the chip; a metal redistribution layer 7 electrically connected to the PAD 22 of the chip is formed on the insulating layer 9; a solder resist layer 10 is formed on the metal redistribution layer 7, an opening is formed on the solder resist layer 10, and a signal derivation structure 8 electrically connected to the metal redistribution layer 7 is formed at the opening of the solder resist layer 10. In the preferred embodiment, the signal derivation structure is a solder ball.

[0059] An opening is formed on the insulating layer 9 so that the metal barrier layer is electrically connected to the metal redistribution layer and further connected to the ground line.

[0060] The present invention introduces a metal barrier layer on the back side of the photosensitive area of ​​the chip wafer to block infrared light, and sets a metal light-shielding layer on the non-photosensitive area on the front side of the chip wafer to block reflected light, thereby effectively improving the optical effect of the image sensor; and the present invention integrates an antenna function on the image sensor chip, so that the antenna structure becomes miniaturized, and at the same time enables the image sensor chip to realize the information transmission function.

[0061] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An image sensor integrated antenna packaging structure, characterized in that: The invention comprises a carrier board and a chip, wherein the front side of the chip has a photosensitive area and a non-photosensitive area, and a PAD and a signal conversion circuit are arranged on the non-photosensitive area; the front side of the chip is bonded to the carrier board; a through hole corresponding to the position of the non-photosensitive area of ​​the chip is arranged on the carrier board; the through hole is filled with a conductive metal; a metal light shielding layer corresponding to the position of the through hole is arranged on the upper and lower surfaces of the carrier board; the metal light shielding layer on the lower surface of the carrier board is used to connect an antenna; a metal barrier layer corresponding to the position of the photosensitive area is arranged on the back side of the chip, and a conductive composite structure electrically connected to the PAD is formed on the chip; The chip is provided with a through hole corresponding to the position of the PAD; the conductive composite structure includes a metal redistribution layer and a signal derivation structure; an insulating layer is formed on the back of the chip, and the insulating layer extends to cover the hole wall of the through hole of the chip; a metal redistribution layer electrically connected to the PAD of the chip is formed on the insulating layer; a solder resist layer is formed on the metal redistribution layer, an opening is formed on the solder resist layer, and a signal derivation structure electrically connected to the metal redistribution layer is formed at the opening of the solder resist layer; An opening is formed on the insulating layer to electrically connect the metal barrier layer to the metal redistribution layer, and the metal barrier layer is connected to the ground line.

2. The image sensor integrated antenna packaging structure according to claim 1, characterized in that: The bonding structure between the carrier and the chip is a bonding structure with a cavity or a bonding structure without a cavity; and when the bonding structure between the carrier and the chip is a bonding structure with a cavity, the bonding structure with a cavity has a cofferdam cavity corresponding to the photosensitive area of ​​the chip.

3. The packaging method of an image sensor integrated antenna packaging structure according to claim 2, characterized in that: The width of the cofferdam cavity is equal to or greater than the width of the photosensitive area of ​​the chip.

4. A packaging method for an image sensor integrated antenna packaging structure, characterized in that: The steps include: S1, providing a carrier board and a chip wafer, wherein the front side of the chip wafer has a photosensitive area and a non-photosensitive area, and a PAD and a signal conversion circuit are provided on the non-photosensitive area, and determining the portion of the carrier board corresponding to the non-photosensitive area of ​​the chip wafer after bonding with the chip wafer; S2, forming a through hole at the portion of the determined carrier corresponding to the non-photosensitive area of ​​the chip wafer, filling the through hole with a conductive metal, and forming a metal light shielding layer on both the upper and lower surfaces of the portion; the metal light shielding layer on the lower surface of the carrier is used to connect the antenna; S3, bonding the front side of the chip wafer to the upper surface of the carrier; S4, forming a metal barrier layer at a position corresponding to the photosensitive area on the back side of the chip wafer; S5, forming a conductive composite structure electrically connected to the PAD of the chip wafer on the chip wafer; S6, cutting the obtained structure into an image sensor integrated antenna packaging structure containing a single chip.

5. The packaging method of the image sensor integrated antenna packaging structure according to claim 4, characterized in that: The carrier plate is glass.

6. The packaging method of the image sensor integrated antenna packaging structure according to claim 4, characterized in that: In step S3, the bonding structure between the carrier and the chip wafer is a cavity bonding structure or a cavity-free bonding structure.

7. The packaging method of the image sensor integrated antenna packaging structure according to claim 4, characterized in that: The conductive composite structure in step S5 includes a metal redistribution layer and a signal derivation structure; the formation process of the conductive composite structure is: S51, forming a through hole at a position of the chip wafer corresponding to the PAD, and forming an insulating layer on the upper surface of the chip wafer, wherein the insulating layer extends and covers the hole wall of the through hole; S52, forming a metal redistribution layer electrically connected to the PAD of the chip wafer on the insulating layer; S53, forming a solder resist layer on the metal redistribution layer, forming an opening in the solder resist layer, and then forming a signal derivation structure electrically connected to the metal redistribution layer at the opening of the solder resist layer.

8. The packaging method of the image sensor integrated antenna packaging structure according to claim 7, characterized in that: An opening is also formed on the insulating layer to electrically connect the metal barrier layer to the metal redistribution layer.

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