TW202437528A - Sensor packaging structure and method for packaging sensor - Google Patents

Abstract

A sensor packaging structure including a substrate, a sensor chip, a bonding wire, a transparent cover plate and a DAF film is provided. The sensor chip is provided in the central area of the substrate and includes a photosensitive area and a non-photosensitive area. A plurality of bonding pads are provided on a surface of the non-photosensitive area away from the substrate. Conductive pads corresponding to the bonding pads one by one are provided on a surface of the peripheral area of the substrate adjacent to the sensor chip. An end of the bonding wire is connected to the bonding pad and the other end of the bonding wire is connected to the conductive pad. The transparent cover plate is provided on a side of the sensor chip away from the substrate. The DAF film is located between the transparent cover plate and the sensor chip, and provided with a through hole opposite to the photosensitive area. The DAF film include a first portion covering the non-photosensitive area. A side surface of the first portion deviated from the sensor chip is attached to the transparent cover plate. A method for packaging senor is also provided.

Description

Packaging structure of sensor and packaging method thereof

The present invention relates to a sensor technology field, and in particular to a sensor packaging structure and a packaging method thereof.

A sensor is a detection device that can sense the information being measured and convert the sensed information into electrical signals or other required forms of information output according to certain rules to meet the requirements of information transmission, processing, storage, display, recording and control.

A sensor with a semiconductor chip inside, which can have various packaging structures, such as chip on board (COB) packaging, chip on film (COF) packaging, chip on glass (COG) packaging, wafer level chip scale (WLCSP) packaging, ball grid array (IBGA) packaging, and plastic lead-free chip carrier (PLCC) packaging.

A sensor in the related art is packaged in a chip-on-board (COB) packaging method, and the chip is electrically connected to the PCB board through a wire bonding process. Specifically, the cut chip is pasted on the substrate, and the conductive pads on the chip are led out through wires and electrically connected to the substrate. Then, epoxy resin is applied to the non-photosensitive area of the chip to form a barrier, and a transparent cover is covered on the barrier, so that the photosensitive area of the chip is packaged in the space formed by the substrate, the barrier and the transparent cover to protect the photosensitive area.

In the packaging process of the above-mentioned sensor, it is difficult to control the amount of epoxy resin applied, and it is easy to cause overflow and uneven application of epoxy resin, thereby affecting the photosensitivity and sealing performance of the photosensitive area.

The present invention provides a packaging structure and a packaging method for a sensor, which are useful for avoiding defects such as glue overflow and uneven coating, thereby improving the photosensitivity and sealing performance of the packaged sensor.

The sensor packaging structure of the present invention comprises a substrate, wherein the substrate comprises a central area and a peripheral area surrounding the central area; a sensor chip, wherein the sensor chip is mounted in the central area, wherein the sensor chip comprises a photosensitive area and a non-photosensitive area surrounding the photosensitive area, wherein a plurality of pads are arranged on a side surface of the non-photosensitive area away from the substrate, and a conductive pad corresponding to the pads is arranged on a side surface of the peripheral area close to the sensor chip; A bonding wire, one end of which is connected to the pad, and the other end of which is connected to the conductive pad; a transparent cover plate, which is arranged on a side of the sensor chip away from the substrate; and a DAF film, which is located between the transparent cover plate and the sensor chip, and the DAF film is provided with a through hole opposite to the photosensitive area, and the DAF film includes a first part covering the non-photosensitive area, and the first part is bonded to the transparent cover plate on a side surface away from the sensor chip.

The packaging structure of the sensor of the present invention is beneficial to improving the photosensitivity and sealing performance of the sensor after packaging. Specifically, the present application uses a DAF film as a barrier. The DAF film is provided with a through hole, and the DAF film includes a first part, and the first part is bonded to a transparent cover plate on a side surface facing away from the sensor chip. During assembly, the DAF film can be bonded to the transparent cover plate first, and then the two can be pressed together toward the sensor chip. After the pressing is completed, the through hole is directly opposite to the photosensitive area to avoid the photosensitive area of the sensor chip. The first part covers the non-photosensitive area of the sensor chip, and also wraps a portion of the bonding wire in the non-photosensitive area. At this time, since the thickness and amount of the DAF film can be controlled, the DAF film is sticky but does not flow before curing, so the glue overflow phenomenon in the previous technology will not occur after pressing, so that the photosensitive area will not be covered by the DAF film, which is conducive to improving the photosensitivity of the sensor after packaging. Secondly, the thickness of the DAF film is uniform, and the DAF film and the transparent cover plate and the DAF film and the non-photosensitive area of the sensor chip can be tightly fitted during pressing, which is also conducive to improving the support and sealing performance of the DAF film, and further helps to improve the reliability of the sensor after packaging. In addition, DAF film is more common than epoxy resin glue, which is also conducive to reducing the packaging cost of the sensor.

In one embodiment of the present invention, the above-mentioned packaging structure further includes a sealant disposed in the peripheral area, and the sealant is configured to seal the sensor chip, the bonding wire, the first part and the transparent cover.

In one embodiment of the present invention, the DAF film further includes a second portion covering the peripheral area, a surface of the second portion facing away from the sensor chip is bonded to the transparent cover plate, and the bonding wire is located in the DAF film.

In one embodiment of the present invention, the packaging structure further includes a plastic encapsulation column disposed in the peripheral area, the plastic encapsulation column is located outside the second part and the transparent cover plate, and the plastic encapsulation column is configured to seal the second part and the transparent cover plate.

In one embodiment of the present invention, the edge of the DAF film is flush with the edge of the transparent cover plate.

In one embodiment of the present invention, a plurality of external connection terminals are disposed on a surface of the substrate facing away from the sensor chip.

The packaging method of the sensor of the present invention comprises providing a substrate, the substrate comprising a central area and a peripheral area surrounding the central area, a plurality of conductive pads are arranged in the peripheral area; installing a sensor chip in the central area, the sensor chip comprising a photosensitive area and a non-photosensitive area surrounding the photosensitive area, a surface of the non-photosensitive area facing away from the substrate is provided with pads corresponding to the conductive pads one by one; providing a bonding wire, connecting one end of the bonding wire to the pad and the other end to the conductive pad; providing a transparent cover plate; laminating a DAF film on one side of the transparent cover plate, the DAF film being provided with a through hole; laminating the DAF film to the sensor chip so that the through hole is opposite to the photosensitive area and the DAF film covers the non-photosensitive area.

In one embodiment of the present invention, the packaging method of the sensor further includes filling the peripheral area with a sealant, the sealant is tightly attached to the outer wall of the DAF film and the outer wall of the transparent cover plate, and the sealant is configured to seal the sensor chip, bonding wire, DAF film and transparent cover plate.

The packaging method of the sensor of the present invention comprises providing a substrate, the substrate comprising a central area and a peripheral area surrounding the central area, the peripheral area being provided with a plurality of conductive pads; installing a sensor chip in the central area, the sensor chip comprising a photosensitive area and a non-photosensitive area surrounding the photosensitive area, the non-photosensitive area being provided with pads corresponding to the conductive pads on a side surface facing away from the substrate; providing bonding wires to connect the conductive pads to the substrate; One end of the bonding wire is connected to the pad, and the other end is connected to the conductive pad; a transparent cover is provided; a DAF film is bonded to one side of the transparent cover, the DAF film is provided with a through hole, and the DAF film includes a first part and a second part; the DAF film is bonded to the sensor chip so that the through hole is opposite to the photosensitive area, the first part covers the non-photosensitive area, and the second part covers the peripheral area, and the bonding wire is located in the DAF film.

In one embodiment of the present invention, the packaging method of the sensor further includes arranging a plastic encapsulation column in the peripheral area, the plastic encapsulation column is tightly attached to the outer wall of the DAF film and the outer wall of the transparent cover plate, and the plastic encapsulation column is configured to seal the second part and the transparent cover plate.

In order to make the above-mentioned purposes, features and advantages of the present invention more clearly understandable, the specific implementation of the present invention is described in detail below in conjunction with the drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

In the description of the present invention, it is necessary to understand that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

In the present invention, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", "fixation" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection between two components or an interaction relationship between two components, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

As shown in FIG1 , it is a schematic diagram of a sensor packaging structure 1 in the prior art. It includes a substrate 2, a sensor chip 3 disposed on the substrate 2, a bonding wire 4 connecting the substrate 2 and the sensor chip 3, a dam 5 located at the edge of the sensor chip 3, a cover plate 6 located on the dam 5, and a sealant 7 located on the cover plate 6 and the outer side of the sensor chip 3. The sealant 7 is used to seal the sensor 3 and the cover plate 6. The sensor chip 3 includes a photosensitive area 31 and a non-photosensitive area 32 surrounding the photosensitive area. The dam 5 is located in the non-photosensitive area 32 and is formed by curing epoxy resin. The photosensitive area 31 of the sensor chip 3 is encapsulated in the space formed by the substrate 2, the dam 5 and the cover plate 6 to protect the photosensitive area 31.

The packaging structure 1 of the sensor has the following problems: the amount of epoxy resin applied is difficult to control, resulting in overflow when the epoxy resin is squeezed by the cover plate 6, and the excess glue will cover the photosensitive area 31, thereby affecting the performance of the sensor. In addition, the epoxy resin is prone to uneven application, resulting in poor adhesion between the formed barrier 5 and the cover plate 6, which will also affect the sealing performance and support performance of the barrier 5, and is not conducive to improving the reliability of the sensor.

Based on this, the present application proposes a packaging structure and a packaging method for a sensor, so as to avoid defects such as glue overflow and uneven coating, thereby improving the photosensitivity and reliability of the packaged sensor.

The embodiment of the first aspect of the present application provides a sensor package structure 100. As shown in FIG2 , the package structure 100 includes a substrate 110, a sensor chip 120, bonding wires 130, a transparent cover plate 140, and a DAF (die attach film) film 150. The substrate 110 includes a central area 110a and a peripheral area 110b surrounding the central area 110a. The sensor chip 120 is mounted on the central area 110a, and the sensor chip 120 includes a photosensitive area 120a and a non-photosensitive area 120b surrounding the photosensitive area 120a. A plurality of pads 121 are disposed on the side of the non-photosensitive area 120b facing away from the substrate 110, and a conductive pad 111 corresponding to each of the pads 121 is disposed on the side of the peripheral area 110b close to the sensor chip 120. One end of the bonding wire 130 is connected to the pad 121, and the other end is connected to the conductive pad 111. A transparent cover plate 140 is disposed on the side of the sensor chip 120 facing away from the substrate 110. The DAF film 150 is located between the transparent cover plate 140 and the sensor chip 120. The DAF film 150 is provided with a through hole 151 opposite to the photosensitive area 120a. The DAF film 150 includes a first portion 152 covering the non-photosensitive area 120b. The first portion 152 is bonded to the transparent cover plate 140 on a side surface facing away from the sensor chip 120.

In the present application, the package structure 100 includes a substrate 110, a sensor chip 120, a bonding wire 130, a transparent cover plate 140 and a DAF film 150. The substrate 110 is a carrier plate structure of the sensor chip 120. The substrate 110 includes a central area 110a and a peripheral area 110b surrounding the central area 110a. The central area 110a refers to an area for placing the sensor chip 120, and the peripheral area 110b refers to an area for realizing electrical connection between the substrate 110 and the sensor chip 120. As shown in FIG. 2 , in the thickness direction of the substrate 110, the substrate 110 can be a stacked structure, which includes a main layer 112 located in the middle, an upper substrate 113 located above the main layer 112, and a lower substrate 114 located below the main layer 112. A single layer or multiple layers of wiring may be formed in the main layer 112, and the upper substrate 113 may be electrically connected to the lower substrate 114 through the wiring of the main layer 112. The main layer 112 may include various materials. For example, the main layer 112 may include at least one of silicon, ceramics, organic materials, glass, or epoxy. In some embodiments, the substrate 110 may be a printed circuit board (PCB) based on epoxy. In some embodiments, the substrate 110 may be rectangular, square, etc., but the shape of the substrate 110 is not limited thereto. The conductive pad 111 is formed in the peripheral area 110b of the upper substrate 113. Furthermore, the conductive pads 111 may be located at two opposite sides of the peripheral area 110b of the upper substrate 113, or the conductive pads 111 may be uniformly disposed in the peripheral area 110b of the upper substrate 113, and the present application does not impose any limitation thereto.

The sensor chip 120 can be mounted on the central area 110a of the substrate 110. For example, the sensor chip 120 can be fixed to the central area 110a of the upper substrate 113 of the substrate 110 through the adhesive layer 123. In some embodiments, the sensor chip 120 can be directly mounted on the substrate 110, or, in other embodiments, the central area 110a of the substrate 110 is provided with a groove, and the sensor chip 120 is placed in the groove and fixedly connected to the substrate 110 through the adhesive layer 123, and the present application does not limit this. Furthermore, the sensor chip 120 can be a CCD (Charge Coupled Device) chip or a CMOS (Complementary Metal-Oxide Semiconductor) chip, etc., and the present application does not limit this.

The sensor chip 120 includes a photosensitive area 120a and a non-photosensitive area 120b. A plurality of photosensitive pixel units 122 are disposed on a surface of the photosensitive area 120a facing away from the substrate 110, and the photosensitive pixel units 122 can be arranged in an array structure. Each photosensitive pixel unit 122 can absorb incident light, generate and accumulate charges corresponding to the amount of incident light, and then transmit the accumulated charges to the outside through the pixel transistor of the sensor chip 120. Furthermore, a filter and a micro lens can be disposed above the photosensitive pixel unit 122, so as to improve the light absorption efficiency. A plurality of pads 121 are disposed on a surface of the non-photosensitive region 120b facing away from the substrate 110, and the pads 121 are used to realize electrical connection between the sensor chip 120 and the substrate 110. The plurality of pads 121 may be located on two opposite sides of the non-photosensitive region 120b, or may be evenly disposed in the non-photosensitive region 120b, and the present application does not impose any limitation on this. One-to-one correspondence means that one pad 121 is connected to one conductive pad 111.

The bonding wire 130 may realize the connection between the pad 121 and the conductive pad 111. The bonding wire 130 may include, for example, at least one of gold (Au), copper (Cu), silver (Ag), and aluminum (Al).

The transparent cover 140 is above the sensor chip 120. The transparent cover 140 may include, for example, at least one of transparent glass, transparent resin, or transmissive ceramic. The DAF film 150 is located between the transparent cover 140 and the sensor chip 120. The DAF film 150 is a semi-solid adhesive film that is sticky but does not flow. The DAF film 150 has high elasticity in a semi-solid state and can cover the sensor chip 120 while wrapping the bonding wire 130. After reaching the curing point through baking, the DAF film 150 becomes an irreversible solid, thereby forming a barrier structure for sealing and supporting.

The packaging structure 100 of the sensor of the embodiment of the present application is beneficial to improving the photosensitivity and reliability of the packaged sensor. Specifically, the present application uses a DAF film 150 as a barrier. The DAF film 150 is provided with a through hole 151, and the DAF film 150 includes a first portion 152, and the first portion 152 is bonded to the transparent cover plate 140 on a side surface facing away from the sensor chip 120. During assembly, the DAF film 150 and the transparent cover plate 140 can be bonded first, and then the two can be pressed together toward the sensor chip 120. After the pressing is completed, the through hole 151 is directly opposite to the photosensitive area 120a to avoid the photosensitive area 120a of the sensor chip 120. The first portion 152 covers the non-photosensitive area 120b of the sensor chip 120 and also wraps a portion of the bonding wire 130 in the non-photosensitive area 120b. At this time, since the thickness and amount of the DAF film 150 are controllable, the DAF film 150 is sticky but does not flow before curing, so that the glue overflow phenomenon in the prior art will not occur after pressing, so that the photosensitive area 120a will not be covered by the DAF film 150, which is conducive to improving the photosensitivity of the packaged sensor. Secondly, the thickness of the DAF film 150 is uniform, and during pressing, the DAF film 150 and the transparent cover plate 140 as well as the DAF film 150 and the non-photosensitive area 120b of the sensor chip 120 can be tightly attached, which is also beneficial to improving the support and sealing performance of the DAF film 150, and further to improving the reliability of the packaged sensor. In addition, the DAF film 150 is more common than epoxy resin, which is also beneficial to reducing the packaging cost of the sensor.

In the present application, the DAF film 150 including the first portion 152 covering the non-photosensitive area 120 b means that the DAF film 150 may have only the first portion 152 or may have other portions except the first portion 152 .

When the DAF film 150 has only the first portion 152 , in some embodiments, as shown in FIG. 2 , the package structure 100 further includes a sealant 160 disposed in the peripheral area 110 b , and the sealant 160 is configured to seal the sensor chip 120 , the bonding wire 130 , the first portion 152 , and the transparent cover 140 .

In this embodiment, the package structure 100 further includes a sealant 160. The sealant 160 may be formed on the peripheral area 110b of the upper substrate 113 of the substrate 110 to cover the sensor chip 120, the first portion 152, and the side surface of the transparent cover plate 140. Similarly, the sealant 160 may cover the first portion 152 while covering another portion of the bonding wire 130 in the peripheral area 110b. The sealant 160, together with the DAF film 150, may prevent or reduce the possibility of the photosensitive area 120a of the sensor chip 120 being contaminated by foreign matter, thereby facilitating further improvement of sealing performance and reliability. Additionally, the sealant 160 may also protect the sensor chip 120 from external impact. The sealant 160 may be, for example, an epoxy molding compound (EMC). However, the material of the sealant 160 is not limited to EMC.

In some other embodiments, as shown in FIG. 3 , the DAF film 150 further includes a second portion 153 covering the peripheral area 110 b , a surface of the second portion 153 facing away from the sensor chip 120 is bonded to the transparent cover plate 140 , and the bonding wire 130 is located in the DAF film 150 .

In this embodiment, the DAF film 150 includes a first portion 152 covering the non-photosensitive area 120b and a second portion 153 covering the peripheral area 110b. In other words, the DAF film 150 covers both the non-photosensitive area 120b of the sensor chip 120 and the peripheral area 110b of the substrate 110. At this time, the bonding wire 130 is also entirely located in the DAF film 150. In this way, on the first hand, the amount and thickness of the DAF film 150 can be controlled, and the glue overflow phenomenon in the prior art will not occur after pressing, so that the photosensitive area 120a will not be covered by the DAF film 150, which is conducive to improving the photosensitivity of the sensor after packaging. Secondly, the thickness of the DAF film 150 is uniform and highly elastic, and during pressing, the DAF film 150 and the transparent cover plate 140, the DAF film 150 and the non-photosensitive area 120b of the sensor chip 120, and the DAF film 150 and the peripheral area 110b of the substrate 110 can all be tightly bonded, which is also beneficial to improving the support performance and sealing performance of the DAF film 150, and further to improving the reliability of the packaged sensor. Thirdly, the first part 152 and the second part 153 are bonded to the transparent cover plate 140 on one side away from the sensor chip 120, which is beneficial to increasing the bonding area between the transparent cover plate 140 and the DAF film 150, and further to further improving the sealing performance and reliability of the packaged sensor.

Furthermore, as shown in FIG. 4 , the packaging structure 100 further includes a plastic molding column 170 disposed in the peripheral area 110 b . The plastic molding column 170 is located outside the second portion 153 and the transparent cover 140 . The plastic molding column 170 is configured to seal the second portion 153 and the transparent cover 140 .

In this embodiment, the package structure 100 further includes a plastic encapsulation column 170, which can be formed on the peripheral area 110b of the upper substrate 113 of the substrate 110 to closely adhere to the outer surface of the second part 153 of the DAF film 150 and the outer surface of the transparent cover plate 140, thereby forming a seal for the second part 153 and the transparent cover plate 140. In this way, through the double protection of the DAF film 150 and the plastic encapsulation column 170, the possibility of the photosensitive area 120a of the sensor chip 120 being contaminated by foreign matter can be prevented or reduced, thereby further improving the reliability after packaging. In addition, the plastic encapsulation column 170 can further protect the sensor chip 120 from external impact. The plastic encapsulation column 170 can adopt, for example, epoxy molding compound (EMC). However, the material of the plastic pillar 170 is not limited to EMC.

In some embodiments, as shown in FIG. 3 or FIG. 4 , the edge of the DAF film 150 is flush with the edge of the transparent cover plate 140. If the edge of the DAF film 150 is not flush with the edge of the transparent cover plate 140, when manufacturing the plastic molding column 170 located on the outer side of the DAF film 150, a gap may be generated between the plastic molding column 170 and the outer surface of the DAF film 150 or between the plastic molding column 170 and the outer surface of the transparent cover plate 140, which is not conducive to improving the sealing performance of the plastic molding column 170. In addition, since the edge of the DAF film 150 is not flush with the edge of the transparent cover plate 140, the plastic molding column 170 is an irregular shape, which is also inconvenient to manufacture the plastic molding column 170. That is to say, in this embodiment, on the one hand, it is helpful to reduce the difficulty of manufacturing the plastic encapsulation glue column 170, and on the other hand, it is also helpful to improve the sealing effect of the plastic encapsulation glue column 170.

In some embodiments, as shown in FIG. 2 , a plurality of external connection terminals 115 are provided on a side surface of the substrate 110 facing away from the sensor chip 120. The external connection terminals 115 may be provided on a side surface of the lower substrate 114 facing away from the sensor chip 120. The external connection terminals 115 may include, for example, solder balls. Through the external connection terminals 115, the package structure 100 may be connected to an external substrate, thereby realizing external communication of the sensor.

As shown in FIG5 , the second aspect of the present application proposes a sensor packaging method, comprising:

A substrate 110 is provided. The substrate 110 includes a central area 110a and a peripheral area 110b surrounding the central area 110a. A plurality of conductive pads 111 are disposed in the peripheral area 110b.

The sensor chip 120 is mounted in the central area 110a. The sensor chip 120 includes a photosensitive area 120a and a non-photosensitive area 120b surrounding the photosensitive area 120a. The non-photosensitive area 120b is provided with pads 121 corresponding to the conductive pads 111 on a side surface facing away from the substrate 110.

A bonding wire 130 is provided, and one end of the bonding wire 130 is connected to the pad 121 , and the other end of the bonding wire 130 is connected to the conductive pad 111 .

A transparent cover 140 is provided.

A DAF film 150 is attached to one side of the transparent cover plate 140 , and the DAF film 150 is provided with a through hole 151 .

The DAF film 150 is attached to the sensor wafer 120 so that the through hole 151 is opposite to the photosensitive area 120a, and the DAF film 150 covers the non-photosensitive area 120b.

The packaging method of the sensor of the embodiment of the present application uses a DAF film 150 to bond the transparent cover plate 140 and the sensor chip 120 to form a packaging structure 100 as shown in FIG2 , which is beneficial to improving the photosensitivity and reliability of the packaged sensor. Specifically, the sensor chip 120 is mounted in the central area 110a, and the bonding wire 130 connects the pad 121 of the sensor chip 120 to the conductive pad 111 of the substrate 110 to achieve electrical connection between the two. As shown in FIG7 , the sensor chip 120 is first electrically connected to the substrate 110. Then, the DAF film 150 is provided with a through hole 151, and the DAF film 150 is then bonded to the transparent cover plate 140. Finally, the DAF film 150 and the transparent cover plate 140 are pressed together toward the sensor chip 120 and the substrate 110. After the pressing is completed, as shown in FIG. 2 , the through hole 151 is directly opposite to the photosensitive area 120a to avoid the photosensitive area 120a of the sensor chip 120. The DAF film 150 covers the non-photosensitive area 120b of the sensor chip 120, and also wraps a portion of the bonding wire 130 in the non-photosensitive area 120b. At this time, since the thickness and amount of the DAF film 150 are controllable, the DAF film 150 is sticky but does not flow before curing, so that the glue overflow phenomenon in the previous technology will not occur after pressing, so that the photosensitive area 120a will not be covered by the DAF film 150, which is conducive to improving the photosensitivity of the sensor after packaging. Secondly, the thickness of the DAF film 150 is uniform, and before lamination, the DAF film 150 is tightly attached to the transparent cover plate 140 in advance. After lamination, the DAF film 150 is also tightly attached to the non-photosensitive area 120b of the sensor chip 120, which is also beneficial to improve the support performance and sealing performance of the DAF film 150, and further to improve the reliability of the packaged sensor. In addition, the DAF film 150 is more common than epoxy resin, which is also beneficial to reduce the packaging cost of the sensor.

Furthermore, the packaging method further comprises:

The sealant 160 is filled in the peripheral area 110 b . The sealant 160 is closely attached to the outer side wall of the DAF film 150 and the outer side wall of the transparent cover plate 140 . The sealant 160 is configured to seal the sensor chip 120 , the bonding wire 130 , the DAF film 150 and the transparent cover plate 140 .

In this embodiment, the peripheral area 110b is also filled with a sealant 160. The sealant 160 can be formed on the peripheral area 110b of the substrate 110 to cover the sensor chip 120, the DAF film 150, and the side surface of the transparent cover plate 140. Similarly, the sealant 160 can cover the DAF film 150 while covering another part of the bonding wire 130 in the peripheral area 110b. The sealant 160 can prevent or reduce the possibility of the photosensitive area 120a of the sensor chip 120 being contaminated by foreign matter together with the DAF film 150, thereby further improving the sealing of the package. In addition, the sealant 160 can also protect the sensor chip 120 from external impact.

As shown in FIG6 , an embodiment of the third aspect of the present application provides a sensor packaging method, comprising:

A substrate 110 is provided. The substrate 110 includes a central area 110a and a peripheral area 110b surrounding the central area 110a. A plurality of conductive pads 111 are disposed in the peripheral area 110b.

The sensor chip 120 is mounted in the central area 110a. The sensor chip 120 includes a photosensitive area 120a and a non-photosensitive area 120b surrounding the photosensitive area 120a. The non-photosensitive area 120b is provided with pads 121 corresponding to the conductive pads 111 on a side surface facing away from the substrate 110.

A bonding wire 130 is provided, and one end of the bonding wire 130 is connected to the pad 121 , and the other end of the bonding wire 130 is connected to the conductive pad 111 .

A transparent cover 140 is provided.

A DAF film 150 is attached to one side of the transparent cover plate 140 . The DAF film 150 is provided with a through hole 151 . The DAF film 150 includes a first portion 152 and a second portion 153 .

The DAF film 150 is bonded to the sensor chip 120 so that the through hole 151 is opposite to the photosensitive area 120 a , the first portion 152 covers the non-photosensitive area 120 b , and the second portion 153 covers the peripheral area 110 b . The bonding wire 130 is located in the DAF film 150 .

The packaging method of the sensor of the embodiment of the present application uses a DAF film 150 to bond the transparent cover plate 140 and the sensor chip 120 to form a packaging structure 100 as shown in FIG3 , which is beneficial to improving the photosensitivity and reliability of the packaged sensor. Compared with the packaging method of the sensor described in the second aspect, the difference is that in this embodiment, the DAF film 150 includes a first part 152 and a second part 153. After bonding, the first part 152 covers the non-photosensitive area 120b, and the second part 153 covers the peripheral area 110b, and the bonding wire 130 is located in the DAF film 150. In other words, the DAF film 150 covers both the non-photosensitive area 120b of the sensor chip 120 and the peripheral area 110b of the substrate 110. As shown in FIG8 , the sensor chip 120 and the substrate 110 are first electrically connected. Then, the DAF film 150 is provided with a through hole 151, and the DAF film 150 is bonded to the transparent cover plate 140. Finally, the DAF film 150 and the transparent cover plate 140 are pressed together toward the sensor chip 120 and the substrate 110. Since the DAF film 150 has high elasticity, the DAF film 150 includes a first portion 152 and a second portion 153. The DAF film 150 is compressed and deformed by the sensor chip 120 and the substrate 110, and the first portion 152 has a large deformation, and the second portion 153 has a large deformation, thereby forming a structure as shown in FIG. 3, in which the dotted line is the boundary between the first portion 152 and the second portion 153. At this time, the bonding wire 130 is also located in the DAF film 150 as a whole. In this way, firstly, the glue overflow phenomenon in the prior art will not occur after pressing, so that the photosensitive area 120a will not be covered by the DAF film 150, which is conducive to improving the photosensitivity of the packaged sensor. Secondly, the thickness of the DAF film 150 is uniform, and during pressing, the DAF film 150 and the transparent cover plate 140, the DAF film 150 and the non-photosensitive area 120b of the sensor chip 120, and the DAF film 150 and the substrate 110 can all be tightly attached, which is also conducive to improving the support performance and sealing performance of the DAF film 150, and further, it is also conducive to improving the reliability of the packaged sensor. Thirdly, the first portion 152 and the second portion 153 are bonded to the transparent cover plate 140 on one side facing away from the sensor chip 120, thereby increasing the bonding area between the transparent cover plate 140 and the DAF film 150, and further improving the sealing performance and reliability of the packaged sensor.

Furthermore, in some embodiments, the packaging method further comprises:

The plastic molding column 170 is disposed in the peripheral area 110 b . The plastic molding column 170 is closely attached to the outer side wall of the DAF film 150 and the outer side wall of the transparent cover plate 140 . The plastic molding column 170 is configured to seal the second portion 153 and the transparent cover plate 140 .

In this embodiment, the package structure 100 further includes a plastic encapsulation column 170, which can be formed on the peripheral area 110b of the upper substrate 113 of the substrate 110 to closely adhere to the outer surface of the second part 153 of the DAF film 150 and the outer surface of the transparent cover plate 140, thereby forming a seal for the second part 153 and the transparent cover plate 140. In this way, through the double protection of the DAF film 150 and the plastic encapsulation column 170, the possibility of the photosensitive area 120a of the sensor chip 120 being contaminated by foreign matter can be prevented or reduced, thereby improving the sealing performance of the package. In addition, the plastic encapsulation column 170 can further protect the sensor chip 120 from external impact.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it should not be understood as limiting the scope of the invention patent application. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be based on the claims of the attached invention patent application scope.

5: Barrier 6: Cover 100, 1: Package structure 110, 2: Substrate 110a: Central area 110b: Peripheral area 111: Conductive pad 112: Main body layer 113: Upper substrate 114: Lower substrate 115: External connection terminal 120, 3: Sensor chip 120a, 31: Photosensitive area 120b, 32: Non-photosensitive area 121: Pad 122: Photosensitive pixel unit 123: Adhesive layer 130, 4: Bonding wire 140: Transparent cover 150: DAF film 151: Through hole 152: First part 153: Second part 160, 7: Sealant 170: Plastic sealing glue column

FIG. 1 is a schematic diagram of a packaging structure of a sensor in the prior art. FIG. 2 is a schematic diagram of one of the packaging structures of a sensor according to an embodiment of the present invention. FIG. 3 is another schematic diagram of a packaging structure of a sensor according to an embodiment of the present invention. FIG. 4 is another schematic diagram of a packaging structure of a sensor according to an embodiment of the present invention. FIG. 5 is a schematic diagram of a process flow of a packaging method of a sensor according to an embodiment of the present invention. FIG. 6 is a schematic diagram of a decomposition of a packaging structure made by the packaging method shown in FIG. 5. FIG. 7 is a schematic diagram of a process flow of another packaging method of a sensor according to an embodiment of the present invention. FIG. 8 is a schematic diagram of a decomposition of a packaging structure made by the packaging method shown in FIG. 7.

100:Packaging structure

110: Substrate

110a: Central area

110b: Outer area

111: Conductive pad

112: Subject layer

113: Upper substrate

114: Lower substrate

115: External connection terminal

120: Sensor chip

120a: Photosensitive area

120b: non-photosensitive area

121: Solder pad

122: Photosensitive pixel unit

123: Adhesive layer

130:Joining line

140: Transparent cover

150:DAF membrane

151:Through hole

152: Part 1

160: Sealant

Claims (10)

A sensor packaging structure includes: A substrate, the substrate includes a central area and a peripheral area surrounding the central area; A sensor chip, the sensor chip is mounted in the central area, the sensor chip includes a photosensitive area and a non-photosensitive area surrounding the photosensitive area, a surface of the non-photosensitive area facing away from the substrate is provided with a plurality of pads, and a surface of the peripheral area close to the sensor chip is provided with conductive pads corresponding to the pads one by one; A bonding wire, one end of the bonding wire is connected to the pad, and the other end is connected to the conductive pad; A transparent cover plate, the transparent cover plate is provided on the side of the sensor chip facing away from the substrate; and The DAF film is located between the transparent cover plate and the sensor chip. The DAF film is provided with a through hole opposite to the photosensitive area. The DAF film includes a first portion covering the non-photosensitive area. The first portion has a surface facing away from the sensor chip and is bonded to the transparent cover plate. A packaging structure of a sensor as described in claim 1, wherein the packaging structure further includes a sealant disposed in the peripheral area, and the sealant is configured to seal the sensor chip, the bonding wire, the first part and the transparent cover. The packaging structure of the sensor as described in claim 1, wherein the DAF film further includes a second part covering the peripheral area, a surface of the second part facing away from the sensor chip is adhered to the transparent cover plate, and the bonding wire is located in the DAF film. A packaging structure of the sensor as described in claim 3, wherein the packaging structure further includes a plastic encapsulation column arranged in the peripheral area, the plastic encapsulation column is located on the outer side of the second part and the transparent cover plate, and the plastic encapsulation column is configured to seal the second part and the transparent cover plate. A packaging structure of a sensor as described in claim 3 or 4, wherein the edge of the DAF film is flush with the edge of the transparent cover plate. A sensor packaging structure as described in claim 1, wherein a plurality of external connection terminals are provided on a surface of the substrate facing away from the sensor chip. A sensor packaging method includes: Providing a substrate, the substrate including a central area and a peripheral area surrounding the central area, the peripheral area being provided with a plurality of conductive pads; Installing a sensor chip in the central area, the sensor chip including a photosensitive area and a non-photosensitive area surrounding the photosensitive area, the non-photosensitive area being provided with pads corresponding to the conductive pads on a surface of the side away from the substrate; Providing a bonding wire, connecting one end of the bonding wire to the pad and the other end to the conductive pad; Providing a transparent cover plate; Attaching a DAF film to one side of the transparent cover plate, the DAF film being provided with through holes; The DAF film is bonded to the sensor chip so that the through hole is opposite to the photosensitive area and the DAF film covers the non-photosensitive area. The packaging method of the sensor as described in claim 7 further includes: Filling the peripheral area with a sealant, the sealant is closely attached to the outer wall of the DAF film and the outer wall of the transparent cover plate, and the sealant is configured to seal the sensor chip, the bonding wire, the DAF film and the transparent cover plate. A sensor packaging method includes: Providing a substrate, the substrate including a central area and a peripheral area surrounding the central area, the peripheral area being provided with a plurality of conductive pads; Installing a sensor chip in the central area, the sensor chip including a photosensitive area and a non-photosensitive area surrounding the photosensitive area, the non-photosensitive area being provided with pads corresponding to the conductive pads on a surface of the side away from the substrate; Providing a bonding wire, connecting one end of the bonding wire to the pad and the other end to the conductive pad; Providing a transparent cover plate; Attaching a DAF film to one side of the transparent cover plate, the DAF film being provided with a through hole, the DAF film including a first part and a second part; The DAF film is bonded to the sensor chip so that the through hole is opposite to the photosensitive area, the first part covers the non-photosensitive area, the second part covers the peripheral area, and the bonding wire is located in the DAF film. The packaging method of the sensor as described in claim 9 further comprises: A plastic encapsulation column is arranged in the peripheral area, the plastic encapsulation column is closely attached to the outer wall of the DAF film and the outer wall of the transparent cover plate, and the plastic encapsulation column is configured to seal the second part and the transparent cover plate.

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