CN118016686A - Image sensor and method for manufacturing the same - Google Patents

Abstract

The present invention provides an image sensor and a manufacturing method thereof, wherein the back of a photosensitive chip is fixed on a substrate, and the front of the photosensitive chip has a photosensitive area. The pads on the substrate are electrically connected to the pads of the photosensitive chip through wires; the filter and the substrate enclose a storage space, and the photosensitive chip is placed in the storage space. A first light-shielding layer is provided on the surface of the filter away from the photosensitive chip; the projection of the first light-shielding layer on the substrate covers the first annular area between the periphery of the photosensitive area and the side wall of the storage space; a second light-shielding layer is provided on the surface of the filter close to the photosensitive chip; the projection of the second light-shielding layer on the photosensitive chip at least covers the second annular area between the periphery of the photosensitive area and the pressure welding point of the wire on the pad. The present invention effectively blocks glare and noise light through double-sided light-shielding layers without increasing the size of the photosensitive chip itself and the size of the image sensor package, thereby improving the imaging quality of the product and the reliability of the product.

Description

Image sensor and method for manufacturing the same

Technical Field

The present invention belongs to the technical field of image sensor manufacturing, and in particular relates to an image sensor and a manufacturing method thereof.

Background technique

Image sensors are widely used in digital still cameras, cellular phones, security cameras, as well as in medical, automotive and other applications. An image sensor includes a photosensitive chip, which is encapsulated in a cavity formed by a substrate and a filter. The pads on the photosensitive chip are electrically connected to the pads on the substrate through gold wires. A high-temperature reliability test was performed on the image sensor, and it was found that before the high-temperature test, the bonding strength between the gold wire and the pads on the photosensitive chip and the bonding strength between the gold wire and the pads on the substrate were good. However, after the high-temperature test (for example, the bonding test was placed at high temperature for 1000 hours), the bonding strength between the gold wire and the pads and the pads became worse. In severe cases, cracks appeared at the solder joints of the gold wire on the pads and the pads, resulting in failure of the high-temperature reliability test, affecting the reliability of the image sensor product.

Summary of the invention

The purpose of the present invention is to provide an image sensor and a method for manufacturing the same. The present invention effectively blocks glare and noise light through a double-sided shading layer without increasing the size of the photosensitive chip itself or the overall package size of the image sensor, thereby improving product imaging quality while also improving product reliability.

The present invention provides an image sensor, comprising:

A substrate and a photosensitive chip, wherein the back of the photosensitive chip is fixed on the substrate; the front of the photosensitive chip has a photosensitive area and a pad area surrounding the photosensitive area; the pad area is provided with a plurality of pads; the substrate is provided with a plurality of pads, and the pads are electrically connected to the pads through wires;

A filter, wherein the filter and the substrate enclose a receiving space, and the photosensitive chip is placed in the receiving space;

A first light shielding layer is provided on a surface of the filter away from the photosensitive chip; a projection of the first light shielding layer on the substrate covers a first annular area between the periphery of the photosensitive area and the side wall of the accommodating space;

A second light-shielding layer is provided on the surface of one side of the filter close to the photosensitive chip; the projection of the second light-shielding layer on the photosensitive chip at least covers the periphery of the photosensitive area and the second annular area between the bonding point of the wire on the pad.

Furthermore, the material of the first light-shielding layer and the second light-shielding layer may include at least one of black photoresist, plastic, metal and black paint.

Furthermore, the substrate includes a printed circuit board or a ceramic circuit board.

Furthermore, the substrate includes an integrated structure consisting of a bottom plate and side walls extending upward from the circumference of the bottom plate, the filter contacts the top of the side walls of the substrate to enclose a receiving space, and the side walls of the substrate are opaque.

Furthermore, the substrate is a flat plate structure, and the image sensor also includes a frame, which is matched and bonded between the substrate and the filter, and the substrate, the frame and the filter enclose a receiving space; the frame is opaque.

Furthermore, the center of the first annular area and the center of the second annular area both coincide with the center of the photosensitive area.

Furthermore, the material of the filter includes any one of glass, plastic or sapphire.

Furthermore, both side surfaces of the filter along its thickness direction are coated with infrared filter film and/or optical anti-reflection film.

Furthermore, the conductive wire includes at least one of a gold wire, a copper wire, an aluminum wire, a silver wire or an alloy wire.

The present invention also provides a method for manufacturing an image sensor, comprising:

A substrate and a photosensitive chip are provided, and the back side of the photosensitive chip is fixed on the substrate; the front side of the photosensitive chip has a photosensitive area and a pad area surrounding the photosensitive area; the pad area is provided with a plurality of pads; a plurality of pads are provided on the substrate, and the pads are electrically connected to the pads through wires;

Providing a filter, wherein a first light shielding layer and a second light shielding layer are respectively formed on two surfaces of the filter in a thickness direction;

The filter and the substrate are enclosed to form a accommodating space, and the photosensitive chip is placed in the accommodating space; the projection of the first light-shielding layer on the substrate covers a first annular area between the periphery of the photosensitive area and the side wall of the accommodating space; the second light-shielding layer is located in the accommodating space, and the projection of the second light-shielding layer on the photosensitive chip at least covers a second annular area between the periphery of the photosensitive area and the bonding point of the wire on the pad.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention provides an image sensor and a manufacturing method thereof, wherein the image sensor comprises: a substrate and a photosensitive chip, wherein the back of the photosensitive chip is fixed on the substrate; the front of the photosensitive chip has a photosensitive area and a pad area surrounding the photosensitive area; the pad area is provided with a plurality of pads; a plurality of pads are provided on the substrate, and the pads are electrically connected to the pads through wires; a filter, wherein the filter and the substrate enclose a receiving space, and the photosensitive chip is placed in the receiving space; a first light shielding layer is provided on the surface of the filter away from the photosensitive chip; the projection of the first light shielding layer on the substrate covers the first annular area between the periphery of the photosensitive area and the side wall of the receiving space; a second light shielding layer is provided on the surface of the filter close to the photosensitive chip; the projection of the second light shielding layer on the photosensitive chip at least covers the second annular area between the periphery of the photosensitive area and the pressure welding point of the wire on the pad. The present invention effectively shields glare and noise light through a double-sided light shielding layer without increasing the size of the photosensitive chip itself and the size of the image sensor package, thereby improving the product imaging quality and the product reliability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the structure of an image sensor according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of the structure of an image sensor according to a second embodiment of the present invention.

FIG. 3 is a schematic diagram of the structure of an image sensor.

FIG. 4 is a schematic diagram of another image sensor structure.

FIG. 5 is a schematic flow chart of a method for manufacturing an image sensor according to an embodiment of the present invention.

The reference numerals are as follows:

10-substrate; 10a-bottom plate; 10b-side wall; 11-solder pad; 20-photosensitive chip; 20a-photosensitive area; 20b-solder pad area; 21-solder pad; 30-filter; 31-first light-shielding layer; 32-second light-shielding layer; B-width of first non-functional light-shielding area; C-thickness of filter; D-width of second light-shielding layer; θ-maximum angle of incidence; W-wire; 41-substrate; 42-frame; 02-second black light-resistance layer; 01-first black light-resistance layer; A-distance between filter and photosensitive chip; E-width of second non-functional light-shielding area.

Detailed ways

The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

For ease of description, some embodiments of the present application may use spatially relative terms such as "above", "below", "top", "below", etc. to describe the relationship between one element or component and another (or other) elements or components as shown in the various figures of the embodiments. It should be understood that in addition to the orientations described in the drawings, the spatially relative terms are also intended to include different orientations of the device in use or operation. For example, if the device in the drawings is turned over, the elements or components described as being "below" or "below" other elements or components will subsequently be positioned as being "above" or "above" other elements or components. The terms "first", "second", etc. below are used to distinguish between similar elements and are not necessarily used to describe a specific order or time sequence. It is to be understood that these terms used in this way are interchangeable where appropriate.

An embodiment of the present invention provides an image sensor, as shown in FIG1 , including:

The substrate 10 and the photosensitive chip 20, the back of the photosensitive chip 20 is fixed on the substrate 10; the front of the photosensitive chip 20 has a photosensitive area 20a and a pad area 20b surrounding the photosensitive area 20a; the pad area 20b is provided with a plurality of pads 21; the substrate 10 is provided with a plurality of pads 11, and the pads 11 are electrically connected to the pads 21 through wires W;

The filter 30 and the substrate 10 enclose a receiving space, and the photosensitive chip 20 is placed in the receiving space;

A first light shielding layer 31 is disposed on the surface of the filter 30 away from the photosensitive chip 20; the projection of the first light shielding layer 31 on the substrate 10 covers the periphery of the photosensitive area 20a and the first annular area between the side wall of the accommodating space;

A second shading layer 32 is provided on the surface of the filter 30 close to the photosensitive chip 20 ; the projection of the second shading layer 32 on the photosensitive chip 20 at least covers the second annular area between the periphery of the photosensitive area 20 a and the bonding point of the wire W on the bonding pad 21 .

Specifically, in the first embodiment, as shown in FIG1 , the substrate 10 includes a structure having an intermediate accommodating cavity integrally formed of a bottom plate 10a and a side wall 10b extending upward from the circumference of the bottom plate 10a. The substrate 10 is, for example, a printed circuit board or a ceramic circuit board. A pad 11 is provided on the substrate 10 in the peripheral area of the photosensitive chip 20. The wire W can electrically connect the pad 11 with the pad 21 by pressure welding. The photosensitive chip 20 is packaged on the substrate 10, and the photosensitive chip 20 is, for example, packaged by a ceramic substrate planar grid array or an organic substrate planar grid array. The wire W includes at least one of a gold wire, a copper wire, an aluminum wire, a silver wire or an alloy wire. The filter 30 contacts the top of the side wall 10b of the substrate 10 and encloses a accommodating space, and the back of the photosensitive chip 20 can be bonded and fixed to the bottom plate 10a to fix the photosensitive chip 20 in the accommodating space. The side wall forming the accommodation space is light-proof. In this example, the side wall 10 b of the substrate 10 is the side wall forming the accommodation space. The side wall 10 b of the substrate 10 is light-proof to prevent light from entering from the side wall of the accommodation space and causing interference to the photosensitive chip 20 .

In the second embodiment, as shown in FIG. 2 , the substrate 41 is a flat structure, and the substrate 41 is, for example, a printed circuit board or a ceramic circuit board. The image sensor also includes a frame 42, and the frame 42 is matched and bonded between the substrate 41 and the filter 30. The substrate 41, the frame 42 and the filter 30 enclose a receiving space; the photosensitive chip 20 is placed in the receiving space. The side walls of the receiving space are opaque. In this example, the frame 42 forms the side walls of the receiving space. The frame 42 is opaque to prevent light from entering from the side walls of the receiving space and interfering with the photosensitive chip 20. The frame 42 can be formed by curing the frame glue or by other suitable opaque materials.

The photosensitive chip 20 is an image sensor chip. The working principle of the photosensitive chip 20 is as follows: the image light from the external scene is usually incident on the photosensitive chip 20 from directly above the photosensitive area 20a. The photosensitive chip 20 includes a plurality of pixel units, and the pixel unit includes a photosensitive element, so that each photosensitive element absorbs a portion of the incident image light. Each photosensitive element included in the photosensitive chip 20 generates an image charge immediately after absorbing the image light. The amount of the generated image charge is proportional to the intensity of the image light. The generated image charge can be used to generate an image representing the external scene.

As shown in Figures 1 and 2, the material of the filter 30 includes any one of glass, plastic or sapphire. Both sides of the filter 30 along its thickness direction can be coated with infrared filter film and/or optical anti-reflection film as needed.

The materials of the first light shielding layer 31 and the second light shielding layer 32 may include at least one of black photoresist, plastic, metal and black paint. The materials of the first light shielding layer 31 and the second light shielding layer 32 are, for example, both black photoresist, which is a material with a photosensitive effect and can be opaque after curing. The black photoresist is exposed to form a preset size. In this embodiment, the first light shielding layer 31 and the second light shielding layer 32 can be formed by an exposure process. The process is simple and easy to control, and the shape and size of the first light shielding layer 31 and the second light shielding layer 32 can be very precise. Of course, the material of the first light shielding layer 31 and the second light shielding layer 32 is not limited to black photoresist, but can also be plastic or metal materials, so as to have stronger wear resistance and stability; the material of the first light shielding layer 31 and the second light shielding layer 32 can also be black paint, which can be formed by spraying and baking processes. The process of forming the first light shielding layer 31 and the second light shielding layer 32 is not limited to the exposure process, but can also be a coating or sputtering process.

A first light shielding layer 31 is disposed on the surface of the filter 30 away from the photosensitive chip 20; the projection of the first light shielding layer 31 on the substrate 10 covers the first annular area between the periphery of the photosensitive area 20a and the side wall of the accommodation space. Exemplarily, the first light shielding layer 31 is a rectangular ring or a square ring when viewed from above. The center of the first annular area coincides with the center of the photosensitive area 20a.

A second light shielding layer 32 is provided on the surface of one side of the filter 30 close to the photosensitive chip 20; the projection of the second light shielding layer 32 on the photosensitive chip 20 at least covers the second annular area between the periphery of the photosensitive area 20a and the bonding point of the wire W on the pad 21. Exemplarily, the second light shielding layer 32 is a rectangular ring or a square ring when viewed from above. When viewed from above, the periphery of the photosensitive area 20a serves as the inner circle boundary of the second annular area, and the second annular area extends away from the center of the photosensitive area 20a to at least cover the bonding point of the wire W on the pad 21, so as to prevent, for example, incident light from entering the thickness range of the filter 30 and irradiating the non-photosensitive area (the area outside the photosensitive area 20a on the photosensitive chip 20) and the wire W, causing interference such as reflection and noise light. The center of the second annular area coincides with the center of the photosensitive area 20a.

FIG3 is a schematic diagram of the structure of an image sensor. In FIG3 , a second black photoresist layer 02 is provided on one side surface (lower surface) of the filter 30 close to the photosensitive chip 20, and no black photoresist layer is provided on the upper surface of the filter 30. The second black photoresist layer 02 is provided on the lower surface of the filter 30, and the second black photoresist layer 02 is encapsulated in a cavity surrounded by the substrate 10 and the filter 30. The second black photoresist layer 02 effectively absorbs and blocks the reflected light, glare and noise light inside the cavity. Glare and noise light refer to some reflected light and/or refracted light that affect the imaging quality; inside the image sensor, the reflected light and/or refracted light of different materials such as gold wire, mirror surface of bonding glue, and glass edges usually need to be shielded. In-depth research has found that because the material of the second black photoresist layer 02 is black photoresist, it has a certain degree of hygroscopicity. Moisture is sealed in the cavity, and corrosive gases are precipitated or decomposed under high temperature conditions, which accelerates the cracking of the gold wire W pressure solder joints and affects the reliability of the image sensor (moisture in the cavity will affect the bonding force between the gold wire W and the pad 21 or the pad 11 after high-temperature reliability testing); and there is a gap between the second black photoresist layer 02 and the side wall 10b, and there is a light leakage defect at the outer edge gap. The solution in which the second black photoresist layer 02 is set on the lower surface of the filter 30 has better glare and noise light shielding capabilities, but poor high-temperature reliability, and the test cannot pass the high-temperature 1000-hour verification.

FIG4 is a schematic diagram of another image sensor structure. In FIG4 , a first black photoresist layer 01 is provided on the side surface (upper surface) of the filter 30 away from the photosensitive chip 20, and no black photoresist layer is provided on the lower surface of the filter 30. The maximum incident angle of light is also θ, tanθ＝(A+C)/E (A is the distance between the filter and the non-photosensitive area of the photosensitive chip, C is the thickness of the filter, and E is the width of the second non-functional light-shielding area). In-depth research has found that compared with the design of setting the second black photoresist layer 02 on the lower surface of the filter 30 in FIG3 , the design of setting the first black photoresist layer 01 on the upper surface of the filter 30 in FIG4 has higher requirements on the size of the photosensitive chip 20, causing light transmission within the range of the filter thickness C, resulting in a larger size of the second non-functional light-shielding area width E. The photosensitive chip 20 is rectangular or square, and accordingly, the photosensitive chip 20 extends outward from the photosensitive area 20a in four directions, front, back, left, and right, so that the size of the photosensitive chip 20 itself and the overall packaging size of the image sensor need to be larger, and the overall cost is higher. Therefore, the scheme of setting the first black photoresist layer 01 on the upper surface of the filter 30 will inevitably increase the size of the non-photosensitive area of the photosensitive chip 20 in order to solve the light leakage problem caused by the filter thickness C, resulting in a larger final size of the photosensitive chip 20 product. The scheme of setting the first black photoresist layer 01 on the upper surface of the filter 30 has poor glare and noise light shielding performance, and requires a larger photosensitive chip 20 size. Because the first black photoresist layer 01 is not in the cavity enclosed by the substrate 10 and the filter 30, the first black photoresist layer 01 is not affected by hygroscopicity and high temperature. The high-temperature reliability of this scheme is stable, and the test can be verified by 2000 hours of high temperature.

Continuing with FIG. 1 and FIG. 2 , the present invention provides a first light shielding layer 31 on the upper surface of the filter 30, and a second light shielding layer 32 on the lower surface of the filter 30. The light shielding layer is designed to be provided on both sides of the filter 30, and most of the light shielding layer is on the upper surface of the filter 30, leaving only a small amount of light shielding layer on the lower surface of the filter 30, so as to maintain the original light shielding function. Such a structure can greatly reduce the moisture in the cavity and meet the high temperature reliability requirements of the product.

The first light shielding layer 31 and the second light shielding layer 32 of the present invention are used to block the interference of glare and noise light on imaging. Without changing the size and performance of the photosensitive chip 20 itself and the overall packaging size of the image sensor, the design of setting light shielding layers on the upper and lower surfaces of the filter 30 is adopted, and the maximum incident angle of light is the same θ, tanθ＝C/D, (C is the thickness of the filter, and D is the width of the second light shielding layer). The width D of the second light shielding layer is smaller than the size of the second black photoresist layer 02 in Figure 3.

The present invention sets a first light shielding layer 31 on the upper surface of the filter 30, and sets a second light shielding layer 32 on the lower surface of the filter 30. The second light shielding layer 32 is set in a smaller size in the product cavity, absorbs less moisture, improves the reliability of the image sensor product package under high temperature conditions, reduces the influence of the corrosive gas precipitated or decomposed by the second light shielding layer 32 on the product solder joints, and thus improves the quality and performance of the product. Moreover, the light leakage within the filter thickness C range caused by the first light shielding layer 31 being set on the upper surface of the filter 30 is just blocked by the second light shielding layer 32, thereby maintaining the light shielding performance while not increasing the size of the width B of the first non-functional light-shielding area. A small amount of the second light shielding layer 32 on the lower surface of the filter 30 compensates for the lack of light shielding of the first light shielding layer 31 on the upper surface of the filter 30. The present invention has both good glare and noise light shielding characteristics, and takes into account the design of a small amount of the second light shielding layer 32 locally on the lower surface, thereby improving product reliability. In addition, since the first light-shielding layer 31 is arranged on the upper surface of the filter 30 and is located outside the storage space enclosed by the filter 30 and the substrate 10, the outer boundary of the first light-shielding layer 31 is no longer restricted or interfered by the side walls of the storage space. The first light-shielding layer 31 can extend outward to ensure that no light leaks from the inner wall of the side wall of the storage space, thereby obtaining better light-shielding performance.

The present invention also provides a method for manufacturing an image sensor, as shown in FIG. 1 and FIG. 5 , comprising:

Step S1, providing a substrate 10 and a photosensitive chip 20, fixing the back side of the photosensitive chip 20 on the substrate 10; the front side of the photosensitive chip 20 has a photosensitive area 20a and a pad area 20b surrounding the photosensitive area 20a; the pad area 20b is provided with a plurality of pads 21; the substrate 10 is provided with a plurality of pads 11, and the pads 11 are electrically connected to the pads 21 through wires W;

Step S2, providing a filter 30, and forming a first light shielding layer 31 and a second light shielding layer 32 on two surfaces of the filter 30 in a thickness direction, respectively;

Step S3, enclose the filter 30 and the substrate 10 to form a accommodating space, and place the photosensitive chip 20 in the accommodating space; the projection of the first light-shielding layer 31 on the substrate 10 covers the first annular area between the periphery of the photosensitive area 20a and the side wall of the accommodating space; the second light-shielding layer 32 is located in the accommodating space, and the projection of the second light-shielding layer 32 on the photosensitive chip 20 at least covers the second annular area between the periphery of the photosensitive area 20a and the bonding point of the wire W on the pad 21.

The wire W includes at least one of a gold wire, a copper wire, an aluminum wire, a silver wire or an alloy wire. The wire W can be bonded (or pressure welded) on the pad 11 or the pad 21 by thermosonic bonding. The filter 30 and the substrate 10 can be enclosed by gluing to form a accommodating space. The material of the first light shielding layer 31 and the second light shielding layer 32 are, for example, black photoresist, which is a material with a photosensitive effect and can be opaque after curing. The black photoresist is exposed to form a preset size. In this embodiment, the first light shielding layer 31 and the second light shielding layer 32 can be formed by an exposure process. The process is simple and easy to control, and the shape and size of the first light shielding layer 31 and the second light shielding layer 32 can be very precise. The material of the first light shielding layer 31 and the second light shielding layer 32 can also be black paint, which can be formed by spraying and baking processes. The process of forming the first light shielding layer 31 and the second light shielding layer 32 is not limited to an exposure process, but can also be a coating or sputtering process.

In summary, the present invention provides an image sensor and a manufacturing method thereof, wherein the image sensor comprises: a substrate and a photosensitive chip, wherein the back of the photosensitive chip is fixed on the substrate; the front of the photosensitive chip has a photosensitive area and a pad area surrounding the photosensitive area; the pad area is provided with a plurality of pads; a plurality of pads are provided on the substrate, and the pads are electrically connected to the pads through wires; a filter, wherein the filter and the substrate enclose a receiving space, and the photosensitive chip is placed in the receiving space; a first light shielding layer is provided on the surface of the filter away from the photosensitive chip; the projection of the first light shielding layer on the substrate covers the first annular area between the periphery of the photosensitive area and the side wall of the receiving space; a second light shielding layer is provided on the surface of the filter close to the photosensitive chip; the projection of the second light shielding layer on the photosensitive chip at least covers the second annular area between the periphery of the photosensitive area and the pressure welding point of the wire on the pad. The present invention effectively blocks glare and noise light through a double-sided light shielding layer without increasing the size of the photosensitive chip itself and the size of the image sensor package, thereby improving the product imaging quality and the product reliability.

In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the method disclosed in the embodiment, since it corresponds to the device disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

The above description is only a description of the preferred embodiment of the present invention, and is not any limitation on the scope of rights of the present invention. Any technical personnel in this field can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims (10)

1. An image sensor, comprising:

The back of the photosensitive chip is fixed on the substrate; the front surface of the photosensitive chip is provided with a photosensitive area and a welding pad area surrounding the photosensitive area; the welding pad area is provided with a plurality of welding pads; the substrate is provided with a plurality of bonding pads, and the bonding pads are correspondingly and electrically connected with the bonding pads through wires;

the optical filter and the substrate enclose an accommodating space, and the photosensitive chip is arranged in the accommodating space;

A first shading layer is arranged on the surface of one side, far away from the photosensitive chip, of the optical filter; the projection of the first shading layer on the substrate covers a first annular area between the periphery of the photosensitive area and the side wall of the accommodating space; a second shading layer is arranged on the surface of one side, close to the photosensitive chip, of the optical filter; and the projection of the second shading layer on the photosensitive chip at least covers a second annular area between the periphery of the photosensitive area and the pressure welding point of the lead wire on the welding pad.

2. The image sensor of claim 1, wherein the first light shielding layer and the second light shielding layer each comprise at least one of black photoresist, plastic, metal, and black paint.

3. The image sensor of claim 1, wherein the substrate comprises a printed circuit board or a ceramic circuit board.

4. The image sensor of claim 1, wherein the substrate comprises an integral structure of a bottom plate and a side wall extending upward from a periphery of the bottom plate, the optical filter contacts a top of the side wall of the substrate to form an accommodating space, and the side wall of the substrate is opaque.

5. The image sensor of claim 1, wherein the substrate is a flat panel structure, the image sensor further comprising a frame matingly bonded between the substrate and the optical filter; the substrate, the frame and the optical filter are enclosed to form an accommodating space; the frame is opaque.

6. The image sensor of claim 1, wherein a center of the first annular region and a center of the second annular region each coincide with a center of the photosensitive region.

7. The image sensor of claim 1, wherein the filter comprises any one of glass, plastic, or sapphire.

8. The image sensor of claim 7, wherein both side surfaces of the optical filter in the thickness direction thereof are coated with an infrared filter film and/or an optical antireflection film.

9. The image sensor of claim 1, wherein the wire comprises at least one of gold wire, copper wire, aluminum wire, silver wire, or alloy wire.

10. A method for manufacturing an image sensor, comprising:

Providing a substrate and a photosensitive chip, and fixing the back surface of the photosensitive chip on the substrate; the front surface of the photosensitive chip is provided with a photosensitive area and a welding pad area surrounding the photosensitive area; the welding pad area is provided with a plurality of welding pads; the substrate is provided with a plurality of bonding pads, and the bonding pads are correspondingly and electrically connected with the bonding pads through wires;

Providing a light filter, and forming a first light shielding layer and a second light shielding layer on two surfaces of the light filter in the thickness direction;

Enclosing the optical filter and the substrate into an accommodating space, and placing the photosensitive chip in the accommodating space; the projection of the first shading layer on the substrate covers a first annular area between the periphery of the photosensitive area and the side wall of the accommodating space; the second shading layer is positioned in the accommodating space, and the projection of the second shading layer on the photosensitive chip at least covers a second annular area between the periphery of the photosensitive area and the pressure welding point of the lead wire on the welding pad.