CN111361070B

CN111361070B - Packaging method of camera shooting assembly

Info

Publication number: CN111361070B
Application number: CN201811604402.7A
Authority: CN
Inventors: 秦晓珊
Original assignee: Ningbo Semiconductor International Corp
Current assignee: Ningbo Semiconductor International Corp
Priority date: 2018-12-26
Filing date: 2018-12-26
Publication date: 2022-05-10
Anticipated expiration: 2038-12-26
Also published as: CN111361070A

Abstract

A packaging method of a camera shooting assembly comprises the following steps: providing a bearing substrate, and temporarily bonding a photosensitive unit and a functional element on the bearing substrate, wherein the photosensitive unit comprises a photosensitive chip temporarily bonded on the bearing substrate and a light filter attached on the photosensitive chip, and at least the exposed area of the photosensitive chip and the functional element is a plastic package area; and carrying out selective spraying treatment, spraying a plastic packaging material to the plastic packaging area, and curing the plastic packaging material to form a plastic packaging layer located in the plastic packaging area, wherein the plastic packaging layer is at least filled between the photosensitive chip and the functional element. The invention adopts a selective spraying treatment mode to form the plastic packaging layer, improves the packaging efficiency and simultaneously improves the performance of the lens module.

Description

Packaging method of camera shooting assembly

Technical Field

The embodiment of the invention relates to the field of lens modules, in particular to a packaging method of a camera shooting assembly.

Background

Along with the continuous improvement of living standard of people, the amateur life is richer, and photography becomes a common means for people to record the journey and various daily lives, so that electronic equipment (such as mobile phones, tablet computers, cameras and the like) with a shooting function is more and more applied to the daily life and work of people, and the electronic equipment with the shooting function gradually becomes an indispensable important tool for people at present.

Electronic devices with a shooting function are usually provided with a lens module, and the design level of the lens module is one of the important factors for determining the shooting quality. The lens module generally includes a camera module having a photosensitive chip and a lens module fixed above the camera module for forming an image of a subject. In addition, in order to improve the imaging capability of the lens module, a photosensitive chip with a larger imaging area is required, and a passive element such as a resistor and a capacitor and a peripheral chip are usually disposed in the lens module.

Disclosure of Invention

The embodiment of the invention provides a method for packaging a camera shooting assembly, which improves the performance of a lens module while improving the packaging efficiency.

To solve the above problem, an embodiment of the present invention provides a method for packaging a camera module, including: providing a bearing substrate, and temporarily bonding a photosensitive unit and a functional element on the bearing substrate, wherein the photosensitive unit comprises a photosensitive chip temporarily bonded on the bearing substrate and a light filter attached on the photosensitive chip, and at least the exposed area of the photosensitive chip and the functional element is a plastic package area; and carrying out selective spraying treatment, spraying a plastic packaging material to the plastic packaging area, and curing the plastic packaging material to form a plastic packaging layer located in the plastic packaging area, wherein the plastic packaging layer is at least filled between the photosensitive chip and the functional element.

Compared with the prior art, the technical scheme of the embodiment of the invention has the following advantages:

the embodiment of the invention adopts a selective spraying treatment mode to form the plastic packaging layer, so that the plastic packaging layer is conveniently and directly formed in the area needing to be formed, the packaging efficiency is improved, the process complexity of forming the packaging layer is reduced, the problem that the photosensitive chip and the functional element in the existing plastic packaging layer are subjected to injection molding pressure is favorably avoided, the internal stress of the plastic packaging layer is small, the photosensitive chip and the functional element are prevented from deforming or cracking, the adhesiveness between the plastic packaging layer and the photosensitive chip and the functional element is improved, and the plastic packaging layer is correspondingly favorable for having good sealing effect on the photosensitive chip and the functional element; in summary, the encapsulation method provided by the embodiment of the invention improves the performance of the lens module while improving the encapsulation efficiency.

Drawings

Fig. 1 to 9 are schematic structural diagrams corresponding to steps in an embodiment of a method for packaging a camera module according to the present invention;

fig. 10 and fig. 11 are schematic structural diagrams corresponding to steps in another embodiment of the packaging method of the camera module according to the present invention;

fig. 12 and 13 are schematic structural diagrams corresponding to steps in a further embodiment of the packaging method of the camera module according to the present invention;

fig. 14 to 16 are schematic structural diagrams corresponding to steps in a further embodiment of the method for packaging a camera module according to the present invention.

Detailed Description

The traditional lens module is mainly assembled by a circuit board, a photosensitive chip, a functional element (such as a peripheral chip) and a lens component, wherein the peripheral chip is usually attached to a peripheral main board, and the photosensitive chip and the functional element are mutually separated; the circuit board is used for supporting the photosensitive chip, the functional element and the lens assembly, and the photosensitive chip, the functional element and the lens module are electrically connected through the circuit board.

However, with the requirement of high-pixel and ultra-thin lens module, the imaging requirement of the lens module is higher and higher, the area of the photosensitive chip is correspondingly increased, and the number of functional elements is correspondingly increased, so that the size of the lens module is larger and larger, and the requirements of miniaturization and thinning of the lens module are difficult to meet. Moreover, the photosensitive chip is usually disposed inside the holder in the lens module, and the peripheral chip is usually disposed outside the holder, so that a certain distance is formed between the peripheral chip and the photosensitive chip, thereby reducing the signal transmission rate. The peripheral chip usually includes a Digital Signal Processor (DSP) chip and a memory chip, which are liable to have adverse effects on the shooting speed and the storage speed, thereby reducing the performance of the lens module.

In order to solve the above problems, a package method for omitting a circuit board is provided, in which a photosensitive chip and a functional element are integrated in a molding layer, and an electrical connection is implemented between the photosensitive chip and the functional element, so that the total thickness of a lens module is reduced, and the distance between the photosensitive chip and the functional element is reduced.

However, the process of forming the plastic package layer is generally an injection molding process (molding), in which after the photosensitive chip and the functional element are placed in a mold, a liquid plastic package material is injected into a mold cavity in the mold, the photosensitive chip and the functional element are wrapped by the plastic package material, and the plastic package material is cooled and then cured to form the plastic package layer. In the injection molding process, the photosensitive chip and the functional element can be subjected to larger injection molding pressure, and the photosensitive chip and the functional element are easy to deform or even break under the injection molding pressure, so that the performance of the packaging structure is invalid, and the packaging fails.

Moreover, the plastic package layer formed by the injection molding process usually wraps the photosensitive chip and the functional element in a full-covering manner, i.e., the plastic package layer covers the top and the side wall of the photosensitive chip and the functional element, so that the inside of the plastic package layer has a relatively large internal stress (stress), and the internal stress also easily causes the photosensitive chip and the functional element to deform or even break, thereby causing package failure.

In order to solve the technical problem, the embodiment of the invention adopts a selective spraying treatment mode to form the plastic packaging layer, so that the plastic packaging layer is conveniently and directly formed in the area where the plastic packaging layer needs to be formed, the packaging efficiency is improved, the process complexity of forming the packaging layer is reduced, the problem that the photosensitive chip and the functional element in the existing plastic packaging layer are subjected to injection molding pressure is favorably avoided, the internal stress of the plastic packaging layer is small, the photosensitive chip and the functional element are prevented from deforming or cracking, the adhesion between the plastic packaging layer and the photosensitive chip and the functional element is improved, and the plastic packaging layer is correspondingly favorable for having a good sealing effect on the photosensitive chip and the functional element; in summary, the encapsulation method provided by the embodiment of the invention improves the performance of the lens module while improving the encapsulation efficiency.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Fig. 1 to 9 are schematic structural diagrams corresponding to steps in an embodiment of a method for packaging a camera module according to the present invention.

Referring to fig. 1, a photosensitive chip 200 is provided.

In this embodiment, the photosensitive chip 200 is a CMOS Image Sensor (CIS) chip. In other embodiments, the photosensitive chip may also be a CCD (charge coupled device) image sensor chip.

Specifically, the photo-sensing chip 200 includes a photo-sensing region 200C and a peripheral region 200E surrounding the photo-sensing region 200C. The light signal receiving surface 201 is located in the light sensing area 200C, and the light sensing chip 200 receives the sensing light radiation signal through the light signal receiving surface 201.

The photo sensor chip 200 includes a plurality of semiconductor photo sensors (not shown), a plurality of filter films (not shown) disposed on the semiconductor photo sensors, and micro lenses 210 disposed on the filter films, wherein the micro lenses 210 correspond to the semiconductor photo sensors one by one, so as to focus the received light radiation signal rays onto the semiconductor photo sensors. The optical signal receiving surface 201 is correspondingly the top surface of the microlens 210.

The photosensitive chip 200 is typically a silicon-based chip fabricated by using an integrated circuit fabrication technology, and the photosensitive chip 200 has a bonding pad for electrically connecting the photosensitive chip 200 to other chips or components. In this embodiment, the photo sensor chip 200 has a first chip pad 220 formed in the peripheral region 200E. In this embodiment, the first chip pad 220 is exposed on the surface of the photosensitive chip 200 on the same side as the optical signal receiving surface 201. In other embodiments, the side of the photo-sensing chip facing away from the light signal receiving surface exposes the first chip pad.

Referring to fig. 2 to 4 in combination, fig. 3 is an enlarged view of one of the filters in fig. 2, and the filter 400 is mounted on the photosensitive chip 200 (shown in fig. 4) to form the photosensitive unit 250 (shown in fig. 4).

The optical filter 400 and the photosensitive chip 200 are mounted in advance, so that the optical signal receiving surface 201 is prevented from being polluted by a subsequent packaging process, and the performance of the photosensitive chip 200 is prevented from being adversely affected by the subsequent packaging process. In addition, the whole thickness of the subsequent lens module is obviously reduced through a mounting mode, so that the requirements of miniaturization and thinning of the lens module are met.

The filter 400 may be an infrared filter glass sheet or a full light-transmitting glass sheet. In this embodiment, the optical filter 400 is an infrared filter glass, and is further configured to eliminate an influence of infrared light in incident light on the performance of the photosensitive chip 200, which is beneficial to improving an imaging effect. Specifically, the filter 400 is an infrared cut filter (IRCF), which may be a blue glass IR cut filter, or an IR cut filter including glass and an IR cut coating (IR cut coating) on a surface of the glass.

In this embodiment, the optical filter 400 includes a surface 401 to be bonded. The surface to be bonded 401 is a surface for mounting with the photosensitive chip 200.

As shown in fig. 3, the filter 400 includes a light-transmitting region 400C and an edge region 400E surrounding the light-transmitting region 400C. After the lens module is formed, the light-transmitting area 400C of the optical filter 400 is used for transmitting external incident light, so that the light signal receiving surface 201 of the photosensitive chip 200 receives a light signal; the edge region 400E is used to reserve a space position for mounting the optical filter 400 and the photosensitive chip 200.

As shown in fig. 4, in the present embodiment, the optical filter 400 is attached to the photosensitive chip 200 through an adhesive structure 410, and the adhesive structure 410 surrounds the light signal receiving surface 201 of the photosensitive chip 200.

The adhesive structure 410 is used to realize the physical connection between the optical filter 400 and the photosensitive chip 200. And the optical filter 400, the bonding structure 410 and the photosensitive chip 200 enclose a cavity (not labeled), so as to prevent the optical filter 400 from directly contacting the photosensitive chip 200, thereby preventing the performance of the photosensitive chip 200 from being adversely affected.

The bonding structure 410 surrounds the light signal receiving surface 201, so that the optical filter 400 above the light signal receiving surface 201 is located on a photosensitive path of the photosensitive chip 200, and further, the optical performance of the photosensitive chip 200 is guaranteed. In this embodiment, the material of the adhesive structure 410 is a dry film (dry film) that can be photo-etched. In other embodiments, the material of the bonding structure may also be polyimide (polyimide), Polybenzoxazole (PBO), or benzocyclobutene (BCB), which can be photo-etched.

The adhesive structure 410 may be formed on the photosensitive chip 200 or on the optical filter 400. In this embodiment, in order to reduce the difficulty of the process for forming the adhesive structure 410, simplify the process steps, and reduce the influence of the process for forming the adhesive structure 410 on the optical signal receiving surface 201, the adhesive structure 410 is formed on the optical filter 400.

Accordingly, the step of forming the photosensitive unit 250 includes: with continued reference to fig. 2, a first carrier substrate 340 is provided; the filter 400 is bonded on the first carrier substrate 340 while facing away from the surface 401 to be bonded.

In this embodiment, the first carrier substrate 340 is a carrier wafer (carrier wafer). In other embodiments, the first carrier substrate may also be other types of substrates.

Specifically, the optical filter 400 is temporarily bonded on the first carrier substrate 340 through the first temporary bonding layer 345. The first temporary bonding layer 345 serves as a release layer to facilitate the subsequent debonding.

In this embodiment, the first temporary bonding layer 345 is a foamed film. In other embodiments, the first temporary bonding layer may also be a Die Attach Film (DAF).

With continued reference to fig. 2, after the optical filter 400 is temporarily bonded on the first carrier substrate 340, an annular bonding structure 410 is formed at an edge region 400E (shown in fig. 3) of the optical filter 400.

Specifically, the step of forming the adhesive structure 410 includes: forming an adhesive material layer (not shown) covering the optical filter 400 and the first temporary bonding layer 345; the bonding material layer is patterned by using a photolithography process, and the remaining bonding material layer of the edge region 400E is remained as the bonding structure 410.

With continued reference to fig. 4, the light signal receiving surface 201 of the light sensing chip 200 is made to face the annular adhesive structure 410, and the peripheral region 200E (shown in fig. 1) of the light sensing chip 200 is attached to the annular adhesive structure 410 to form the light sensing unit 250.

In this embodiment, after the light sensing unit 250 is formed, the first chip pad 220 faces the filter 400.

Referring to fig. 5 in combination, after the photosensitive unit 250 (shown in fig. 4) is formed, the method further includes: attaching the surface of the photosensitive chip 200, which faces away from the light signal receiving surface 201, to the UV film 310; after the attaching step, a first debonding process is performed to remove the first carrier substrate 340 (as shown in fig. 4).

Through the attaching step, the process is ready for the subsequent temporary bonding step, and the UV film 310 can also provide a supporting and fixing function for the photosensitive unit 250 after the first carrier substrate 340 is removed. Specifically, a film sticking machine is adopted to make the UV film 310 cling to the surface of the photosensitive chip 200, which faces away from the light signal receiving surface 201, and also cling to the bottom of a frame 315 with a larger diameter, so that the frame 315 plays a role in film stretching, and the photosensitive unit 250 is separately fixed on the UV film 310. The detailed description of the UV film 310 and the frame 315 will not be repeated here.

In this embodiment, the first temporary bonding layer 345 (shown in fig. 4) is a foamed film, and thus a thermal pyrolysis bonding process is used to perform the first debonding process. Specifically, the first temporary bonding layer 345 is subjected to a heating process to make the foaming surface of the foaming film lose adhesiveness, so as to remove the first carrier substrate 340; after the first carrier substrate 340 is removed, the first temporary bonding layer 345 is removed by tearing.

Referring to fig. 6, a second carrier substrate 320 is provided, and the photosensitive chip 200 and the functional element (not labeled) are temporarily bonded on the second carrier substrate 320, where at least the exposed area of the photosensitive chip 200 and the functional element is a molding region i.

Through the step of temporary bonding, the process is ready for the subsequent packaging integration and electrical integration of each chip and element. The second carrier substrate 320 is also used to provide a process platform for the formation of the subsequent molding layer.

In this embodiment, the second carrier substrate 320 is a carrier wafer. In other embodiments, the second carrier substrate may also be other types of substrates. Specifically, the photosensitive chip 200 and the functional element are temporarily bonded on the second carrier substrate 320 through the second temporary bonding layer 325. In this embodiment, the second temporary bonding layer 325 is a foamed film. For a detailed description of the second temporary bonding layer 325, reference may be made to the foregoing description of the first temporary bonding layer 345 (shown in fig. 4), and details are not repeated here.

The plastic package area I is an area where a plastic package layer is to be formed. In this embodiment, the exposed areas of the photosensitive chip 200 and the functional elements are the plastic package area i. The arrangement direction of the photosensitive chips 200 and the functional elements on the second carrier substrate 320 is an X direction, and a direction parallel to the surface of the second carrier substrate 320 and perpendicular to the X direction is a Y direction.

The temporary bonding step is described in detail below with reference to the accompanying drawings.

Referring to fig. 6, the photosensitive chip 200 is bonded on the second carrier substrate 320 while facing away from the filter 400.

Specifically, the UV film 310 (shown in fig. 5) at the position of the single photosensitive unit 250 is irradiated with ultraviolet light, the UV film 310 irradiated with the ultraviolet light is released from its adhesiveness, and the single photosensitive unit 250 is lifted up by the ejector pins, and then the photosensitive unit 250 is lifted up by the adsorption apparatus, and the photosensitive unit 250 is sequentially peeled off from the UV film 310 and placed on the second carrier substrate 320. The photosensitive units 250 are placed on the second carrier substrate 320 one by one, which is beneficial to improving the position accuracy of the photosensitive units 250 on the second carrier substrate 320, so as to facilitate the normal operation of the subsequent processes.

In this embodiment, after the photo sensor chip 200 is temporarily bonded to the second carrier substrate 320, the first chip pad 220 of the photo sensor chip 200 faces away from the second carrier substrate 320.

It should be noted that, in the present embodiment, after the photosensitive unit 250 is formed, the photosensitive chip 200 is temporarily bonded to the second carrier substrate 320. In other embodiments, the optical filter may be attached to the photosensitive chip after the photosensitive chip is temporarily bonded to the second carrier substrate.

The present embodiment illustrates only one photosensitive unit 250. In other embodiments, when the formed lens module is applied to a bi-camera or array module product, the number of the photosensitive units can also be multiple.

With continued reference to fig. 6, functional elements are temporarily bonded on the second carrier substrate 320.

The functional element is a specific functional element in the image pickup assembly except for the photosensitive chip 200, and the functional element includes at least one of the peripheral chip 230 and the passive element 240. In this embodiment, the functional elements include a peripheral chip 230 and a passive element 240.

The peripheral chip 230 is an active component, and is used to provide peripheral circuits to the photosensitive chip 200 after the electrical connection with the photosensitive chip 200 is subsequently achieved. In this embodiment, the peripheral chip 230 includes one or both of a digital signal processor chip and a memory chip. In other embodiments, the peripheral chips may also include chips of other functional types. For convenience of illustration, only one peripheral chip 230 is illustrated in fig. 6, but the number of the peripheral chips 230 is not limited to one.

The peripheral chip 230 also has pads for electrically connecting the peripheral chip 230 to other chips or components. In this embodiment, the peripheral chip 230 includes a second chip pad 235. In this embodiment, in order to reduce the difficulty of the subsequent electrical connection process, the second chip pad 235 also faces away from the second carrier substrate 320, so that the first chip pad 220 and the second chip pad 235 are located at the same side.

It should be noted that, the peripheral chip 230 and the photosensitive chip 200 are integrated in a subsequently formed plastic package layer, and in order to improve the surface flatness of the plastic package layer and reduce the process complexity of forming the plastic package layer, the thicknesses of the peripheral chip 230 and the photosensitive chip 200 are equal or the thickness difference is small. In this embodiment, the thickness difference between the peripheral chip 230 and the photosensitive chip 200 is-2 micrometers to 2 micrometers.

The passive component 240 may include a resistor, a capacitor, an inductor, a diode, a transistor, a potentiometer, a relay, or a driver, which may be smaller electronic components. For convenience of illustration, only one passive element 240 is illustrated in fig. 6, but the number of the passive elements 240 is not limited to one.

The passive component 240 also has a pad for electrically connecting the passive component 240 with other chips. In this embodiment, the pad of the passive component 240 is an electrode 245. From the foregoing analysis, the electrode 245 also faces away from the second carrier substrate 320, and the thickness difference between the passive component 240 and the photo sensor chip 200 is-2 microns to 2 microns in order to reduce the complexity of the process for forming the molding layer.

In other embodiments, after the photosensitive chip and the functional element are temporarily bonded to the second carrier substrate, the pad of the photosensitive chip faces away from the second carrier substrate, and the pad of the functional element faces toward the second carrier substrate, or both the pad of the photosensitive chip and the pad of the functional element face toward the second carrier substrate.

Referring to fig. 7, a selective spraying process is performed to spray a plastic package material to the plastic package region, and the plastic package material is cured to form a plastic package layer 350 located in the plastic package region, where the plastic package layer 350 is at least filled between the photosensitive chip 200 and a functional element (not labeled).

The molding layer 350 fixes the photosensitive chip 200 and the functional elements (e.g., the peripheral chip 230 and the passive element 240) for realizing package integration of the photosensitive chip 200 and the functional elements; the plastic sealing layer 350 can also play a role in insulation, sealing and moisture protection, and is also beneficial to improving the reliability of the lens module.

The plastic package layer 350 can reduce the space occupied by the bracket in the lens assembly, and can also save a circuit board (such as a PCB), thereby significantly reducing the total thickness of the formed lens module, and meeting the requirements of miniaturization and thinning of the lens module. Moreover, compared with the scheme of mounting the functional elements on the peripheral motherboard, the distance between the photosensitive chip 200 and each functional element can be reduced by integrating the photosensitive chip and the functional elements in the plastic package layer 350, which is beneficial to shortening the electrical connection distance between the photosensitive chip and each functional element, so that the signal transmission rate is increased, and the service performance of the lens module is further improved (for example, the shooting speed and the storage speed are increased).

In this embodiment, the plastic package layer 350 only covering the sidewalls of the photosensitive chip 200 and the functional element is formed by selective spraying, so that the internal stress of the plastic package layer 350 is small, which can effectively prevent the photosensitive chip 200 and the functional element from applying tensile stress or compressive stress due to excessive internal stress, and prevent the photosensitive chip and the functional element from deforming under the action of the tensile stress or the compressive stress, and the plastic package layer 350 only covers the sidewalls of the photosensitive chip 200 and the functional element, so that the internal stress of the plastic package layer 350 is small, the interface performance between the plastic package layer 350 and the photosensitive chip 200 and the functional element is improved, the adhesion between the plastic package layer 350 and the photosensitive chip 200 and the functional element is strong, and the plastic package layer 350 has a good sealing effect on the photosensitive chip 200 and the functional element; in summary, the encapsulation method provided by the invention improves the performance of the lens module while improving the encapsulation efficiency.

Moreover, the process flexibility of the selective spraying treatment is high, and plastic package materials cannot be sprayed to the area outside the plastic package area I; compared with the common injection molding process, a matched mold is not required to be designed, the thickness of the formed plastic package layer 350 is controlled by reasonably controlling the amount of the plastic package material sprayed by the selective spraying treatment, the process complexity of forming the plastic package layer 350 is reduced, and the packaging efficiency is improved.

In addition, the plastic package layer 350 is formed by adopting a selective spraying treatment mode, so that the problem that injection molding pressure is applied to the photosensitive chip 200 and the functional element in the process of forming the plastic package layer in the prior art is solved, adverse effects of the injection molding pressure on the photosensitive chip 200 and the functional element are avoided, the photosensitive chip 200 and the functional element are prevented from deforming or breaking, and the functional integrity of the photosensitive chip 200 and the functional element is ensured.

Accordingly, in the present embodiment, the molding layer 350 exposes the first chip pad 220, the second chip pad 235 and the electrode 245, so as to facilitate the subsequent electrical connection process.

The plastic package material is a plastic package adhesive with fluidity. In this embodiment, the Molding Compound is an Epoxy Molding Compound (EMC) and includes a matrix resin, a curing agent, a coupling agent, and a filler, where the matrix resin is an Epoxy resin, the curing agent is a phenolic resin, and the coupling agent may be a silica powder or a silica powder. In other embodiments, other suitable molding compounds may be used.

In this embodiment, the method of selective spray coating includes: providing a movable spray head; the sprayer is adopted to move above the second bearing substrate 320, and when the sprayer moves above the plastic packaging area I, the sprayer sprays plastic packaging materials to the plastic packaging area I.

Specifically, a spraying device is provided, and the spraying device is provided with a movable spray head; the second carrier substrate 320 is placed on a carrier table (chuck), and the selective spray process is completed using the spray device.

In order to improve the thickness uniformity of the plastic package layer 350, in the selective spraying process, the spray head moves over the same plastic package region i at least twice to form the plastic package layer 350. As for the same plastic package region I, the plastic package layer 350 is formed by spraying the plastic package materials at least twice, and before spraying the plastic package materials for the next time, the plastic package materials sprayed for the previous time flow on the plastic package region I within a certain time and space, the thickness uniformity of the plastic package materials sprayed for the previous time is improved when the plastic package materials are sprayed for the next time, and the thickness uniformity of the finally formed plastic package layer 350 is improved.

In this embodiment, in the selective spraying process, a moving path of the nozzle when the nozzle moves above the plastic sealing region i for the previous time is a first direction, and a moving path of the nozzle when the nozzle moves above the plastic sealing region i for the subsequent time is a second direction, and the second direction is different from the first direction. The advantages of such an arrangement are: since the thickness distribution of the plastic package materials sprayed to the same plastic package region i by the nozzles from different moving paths has differences, when the nozzles with different moving paths are used for spraying the plastic package materials to the same plastic package region i, the thickness distribution with differences makes up for each other, so that the thickness uniformity of the finally formed plastic package layer 350 is improved.

In this embodiment, the arrangement direction of the photosensitive chips 200 and the functional elements on the second carrier substrate 320 is an X direction, and a direction parallel to the surface of the second carrier substrate 320 and perpendicular to the X direction is a Y direction. Accordingly, the moving path of the showerhead moving above the second carrier substrate 320 has a direction including: one or more of + X direction, -X direction, + Y direction, and-Y direction.

The selective spray coating process includes: at least one X-direction spraying step, wherein the X-direction spraying step comprises the following steps: the spray head moves along the + X direction or the-X direction and passes through the plastic package area I along the X direction until the spray head moves through the plastic package areas I in all the X directions; at least one Y-direction spraying step, wherein the Y-direction spraying step comprises the following steps: the sprayer moves in the + Y direction or the-Y direction and passes through the plastic package area I in the Y direction until the sprayer moves above the plastic package areas I in all the Y directions.

In order to improve the thickness uniformity, density and other properties of the plastic package layer 350, the X-direction spraying step and the Y-direction spraying step may be performed alternately until the plastic package layer 350 with a thickness meeting the requirement is formed. When the spraying step in the X direction is changed to the spraying step in the Y direction, the spraying may be performed by moving the nozzle, or the second carrier substrate 320 may be rotated by 90 ° by the carrier stage.

In other embodiments, the step of selectively spraying may further include: at least two X-direction spraying steps, wherein each X-direction spraying step comprises the following steps: the spray head moves along the + X direction and passes through the upper parts of all the plastic packaging areas in the + X direction; then, the spray head moves along the-X direction and passes through the upper parts of all the plastic packaging areas in the-X direction; and the spray head alternately moves along the + X direction and the-X direction until the thickness of the plastic packaging layer meets the process requirement.

It should be noted that, in the scheme of performing the selective spraying treatment by using the X-direction spraying step of spraying at least twice, for the region outside the plastic package region i where the photosensitive chip 200 and the functional element are not disposed, the nozzle may spray the plastic package material to the region; if the area is cut and removed in the subsequent cutting treatment process, the plastic package material is not sprayed on the area.

Correspondingly, in other embodiments, the selective spraying treatment may further include at least two Y-direction spraying steps, and the spray head may alternately move in the + Y direction and the-Y direction until the thickness of the molding layer meets the process requirement. In other embodiments, the direction of the moving path of the spray head may further include: an oblique direction at 45 degrees to the X direction or an oblique direction at 45 degrees to the Y direction.

Before the selective spraying treatment, position information of the plastic package area i on the second carrier substrate 320 is also required to be acquired; and performing the selective spraying treatment based on the acquired position information.

In this embodiment, the step of obtaining the position information of the plastic package area includes: after the photosensitive unit 250 and the functional elements are placed over the second carrier substrate 320 based on the preset position information, the preset position information is used as the position information of the plastic sealing area. In other embodiments, in order to improve the accuracy of the position information and avoid the influence caused by process deviation, the method for obtaining the position information of the plastic package region may further include: after the photosensitive unit and the functional element are arranged on the second bearing substrate, the surface of the second bearing substrate is irradiated by light, and light information reflected by the surface of the second bearing substrate is collected to obtain the position information of the plastic package area. Since the materials of the photosensitive chip 200, the optical filter 400, the functional element, and the second carrier substrate 320 are different, the light information reflected by different materials is different, and the position information of the plastic package region can be obtained by collecting different light information.

Specifically, the method of performing the selective spray coating process based on the acquired position information includes: while the showerhead is moving above the second carrier substrate 320, the real-time position of the showerhead on the second carrier substrate 320 is obtained in real time; and controlling the sprayer to spray the plastic package material to the plastic package area I in the process of moving on the second bearing substrate 320 based on the real-time position and the acquired position information. The real-time position may be directly obtained, or may be obtained by converting the initial position of the nozzle, the moving speed of the nozzle, and the moving time of the nozzle.

The plastic packaging area I is provided with a first boundary and a second boundary which are opposite, the direction of the first boundary pointing to the second boundary is consistent with the moving direction of the spray head, and when the spray head moves through the first boundary and is away from the first boundary by a first distance, the spray head starts to spray plastic packaging materials; and when the spray head moves to a second distance away from the second boundary and does not exceed the second boundary, the spray head finishes spraying the plastic package material.

The first distance should not be too large. If the first distance is too large, the effective spraying area of the spray head passing through the upper part of the same plastic packaging area I once is too small, so that the efficiency of selective spraying treatment is reduced. For this reason, in the present embodiment, the first distance ranges from 0 to 30mm, for example, 5mm, 10mm, 15mm, 25 mm.

The second distance should not be too small, nor too large. If the second distance is too small, the plastic packaging material is easily sprayed to an area where spraying is not expected by the spray head; if the second distance is too large, the effective spraying area of the spray head passing through the upper part of the same plastic packaging area I once is too small, so that the efficiency of selective spraying treatment is reduced. For this purpose, in this embodiment, the second distance ranges from 5nm to 30mm, for example 10mm, 18mm, 23mm, 28 mm.

During the selective spraying process, the vertical distance between the nozzle and the second carrier substrate 320 should not be too small or too large. The closer the vertical distance is, the smaller the area of the area sprayed by the spray head in unit time is, the thicker the thickness of the film layer formed by spraying the plastic package material on the plastic package area I in unit time is, and the smaller the thickness uniformity of the formed film layer is, which is not beneficial to improving the thickness uniformity of the plastic package layer 350; the farther the vertical distance is, the more difficult the position accuracy of the spray head for spraying the plastic package material is to control, and the plastic package material is easily lost.

For this reason, in the present embodiment, the vertical distance between the showerhead and the second carrier substrate 320 is 5mm to 30mm, for example, 10mm, 15mm, 20mm, 28 mm. And, in the process of selective spraying processing, to same plastic envelope district I, along with the volume of the plastic envelope material in the plastic envelope district I increases gradually, the perpendicular distance between shower nozzle and the second bearing substrate 320 reduces gradually, that is to say, the perpendicular distance between shower nozzle and the second bearing substrate 320 is first perpendicular distance when the shower nozzle passes through a certain plastic envelope district I next time, and the perpendicular distance between shower nozzle and the second bearing substrate 320 is the second perpendicular distance when the shower nozzle passes through same plastic envelope district I last time, first perpendicular distance is less than the second perpendicular distance.

In the process of selective spraying treatment, the moving speed of the spray head is not too small or too fast. If the moving speed is too low, under the condition that the flow rate of the plastic package material sprayed by the spray head is certain, the amount of the plastic package material sprayed by the spray head in the process of moving through the plastic package area I in a single time is large, the thickness of a film layer formed in the plastic package area I in a single time is thick, the uniformity of the thickness of the film layer is relatively poor, and the improvement of the uniformity of the thickness of the finally formed plastic package layer 350 is not facilitated; if the moving speed of the spray head is too high, the spraying efficiency of the selective spraying treatment is low, and the packaging efficiency is influenced. For this reason, in the present embodiment, the velocity at which the head moves during the selective spray treatment is 0.01m/s to 0.1m/s, for example, 0.03m/s, 0.05m/s, 0.07m/s, 0.9 m/s.

In the selective spraying process, the flow rate of the plastic packaging material sprayed by the spray head is not too small or too large. If the flow is too small, the spraying efficiency of the selective spraying treatment is correspondingly low, and the packaging efficiency is influenced; if the flow is too big, the plastic packaging material volume that the shower nozzle single removal sprayed through I in-process in plastic packaging district is great, then the thickness of the rete of I single formation in plastic packaging district is thicker, the thickness homogeneity of rete is relatively poor, is unfavorable for improving the thickness homogeneity of plastic packaging layer 350. For this reason, in this embodiment, the flow rate of the plastic molding compound sprayed by the nozzle during the selective spraying process is 1ml/s to 10ml/s, such as 2ml/s, 4mlL/s, 6ml/s, and 9 ml/s.

It should be noted that, in the present embodiment, a movable spray head is provided to implement the selective spray coating process as an example. In other embodiments, the selective spray coating process may further include: providing a nozzle and a movable carrying platform; and placing the second bearing substrate on the movable carrying platform, so that the second bearing substrate moves below the spray head, and when the plastic package area moves below the spray head, the spray head sprays plastic package materials to the plastic package area.

And after the selective spraying treatment is finished, curing the plastic packaging material positioned in the plastic packaging area I. The curing process is used to cure and shape the molding compound, and during the curing process, a cross-linking reaction occurs inside the molding compound to form the molding layer 350 with bending resistance, moisture resistance and heat resistance.

Specifically, the curing process employs steps including: under vacuum, N₂Or baking the plastic package material in the plastic package area I in an inert gas environment.

In this embodiment, the process temperature used for the curing process should not be too low or too high. If the process temperature is too low, the cross-linking reaction in the plastic packaging material is incomplete in the curing process, so that the plastic packaging effect of the plastic packaging layer 350 is affected; if the process temperature is too high, the performance of the photosensitive chip 200 and the functional element is easily affected, and the process temperature is too high, the internal stress of the plastic package layer 350 is relatively large, so that the adhesion between the plastic package layer 350 and the photosensitive chip 200 and the functional element is easily reduced, and the plastic package effect of the plastic package layer 350 is easily affected.

For this reason, in this embodiment, the curing process is performed at a temperature of 120 ℃ to 160 ℃, for example, 130 ℃, 140 ℃, 150 ℃. Curing within the process temperature range, so that the internal crosslinking reaction of the plastic packaging material in the plastic packaging area is gradually completed, and the number of reaction groups and reaction active points in the molecules is gradually reduced, thereby forming a plastic packaging layer 350 with a stable three-dimensional net structure, so that the plastic packaging layer 350 has high strength and high hardness, and the plastic packaging layer 350 is ensured to have high bending resistance, moisture resistance and heat resistance; and the internal stress of the molding layer 350 is moderate, so the adhesion between the molding layer 350 and the photosensitive chip 200 and the functional element is strong, and the adhesion between the molding layer 350 and the second carrier substrate 320 is strong.

In this embodiment, before the curing treatment, the method further includes: and in the process of carrying out the selective spraying treatment, heating the plastic package material positioned in the plastic package area I, wherein the process temperature of the heating treatment is lower than that of the curing treatment.

In the heating process, the flowability of the plastic packaging material in the plastic packaging area I is improved, so that the thickness uniformity of the formed plastic packaging layer 350 is improved; moreover, solvent molecules which hinder the crosslinking reaction exist in the plastic package material, and the heating treatment is beneficial to volatilizing the solvent from the plastic package material, so that the crosslinking reaction degree in the subsequent curing treatment process is improved, and the strength and the hardness of the formed plastic package layer 350 are improved.

The process temperature of the heating treatment is not suitable to be too low or too high. If the process temperature is too low, the flowability of the plastic packaging material is relatively poor, and the volatilization degree of a solvent which can influence the crosslinking reaction in the plastic packaging material is low; if the process temperature is too high, the plastic package material in the plastic package area is easily hardened too early, and the plastic package layer 350 is easily layered.

For this reason, in this embodiment, the process temperature of the heat treatment is 20 ℃ to 120 ℃, for example, 40 ℃, 60 ℃, 80 ℃, 100 ℃. The process temperature adopted by the heating treatment is moderate, so that the plastic package material in the plastic package area is ensured to have proper fluidity, the solvent in the plastic package material is volatilized as much as possible, and meanwhile, the problem of delamination of the plastic package layer 350 caused by overhigh process temperature of the heating treatment can be avoided. The method of the heat treatment may be: the heating treatment is completed by heating the susceptor.

In other embodiments, the curing process may be performed during the selective spraying process.

With combined reference to fig. 8, the packaging method further includes: after the molding layer 350 is formed, a second debonding process is performed to remove the second carrier substrate 320 (as shown in fig. 7).

In this embodiment, a thermal decomposition bonding process is adopted to perform the second de-bonding process, and the second carrier substrate 320 and the second temporary bonding layer 325 are sequentially removed (as shown in fig. 7). For the specific description of the second bonding-releasing process, reference may be made to the foregoing description of the first bonding-releasing process, and details are not repeated here.

With continuing reference to fig. 8, after the second de-bonding process, further comprising: the molding layer 350 is subjected to a dicing process.

A single camera assembly 260 sized to meet the process requirements is formed by dicing, making process preparation for assembly of subsequent lens assemblies. In this embodiment, a laser cutting process is used for scribing.

It should be noted that, in this embodiment, the second de-bonding process is performed first, and then the dicing process is performed. In other embodiments, the second de-bonding process may also be performed after the dicing process; correspondingly, the second bearing substrate can also provide a process platform for the scribing treatment.

Referring to fig. 9, after the dicing process, the method further includes: a wire bonding process is used to form a wire 500 electrically connecting the photosensitive chip 200 and a pad of a functional element (not labeled).

The leads 500 are used to enable electrical integration of the camera assembly 260.

In this embodiment, a wire bonding process is used to electrically connect the photosensitive chip 200 and the functional element, and the wire 500 is a metal wire, for example: gold or aluminum wires. Specifically, the wire 500 electrically connects the first chip pad 220, the second chip pad 235, and the electrode 245.

In other embodiments, the wire bonding process may be performed before the second de-bonding process is performed, so that the second carrier substrate provides a process platform for the wire bonding process.

It should be noted that the first chip pad 220, the second chip pad 235 and the electrode 245 are located on the same side of the molding layer 350, and all face the optical filter 400, so the wire bonding process is performed on one side of the molding layer 350 close to the optical filter 400. Correspondingly, follow-up with the lens subassembly assemble to when in order to obtain the lens module on the plastic envelope layer 350, lead wire 500 can be arranged in the support (holder) of lens subassembly, makes lead wire 500 obtains the protection, is favorable to improving the reliability of lens module, and is convenient for the assembly of lens module in electronic equipment.

With continued reference to fig. 9, after the dicing process is performed on the molding layer 350 and before the wire bonding process, the method further includes: a flexible printed circuit board (FPC) 510 is attached to the molding layer 350.

The FPC board 510 is used to realize electrical connection between the camera module 260 and a subsequent lens module and electrical connection between a subsequent formed lens module and other components without a circuit board. After the lens module is formed subsequently, the lens module can also be electrically connected with other elements in the electronic device through the FPC board 510, so that the normal shooting function of the electronic device is realized.

In this embodiment, the FPC board 510 is attached to the plastic package layer 350 on the side of the optical filter 400, and in the step of the wire bonding process, the wire 500 is electrically connected to the photosensitive chip 200 and the FPC board 510, so that the photosensitive chip 200, the functional element, and the FPC board 510 are electrically connected through the wire 500. Specifically, the lead 500 electrically connects the first chip pad 220 of the photosensitive chip 200 and the FPC board 510.

A connector (connector)520 is formed on the FPC board 510 to electrically connect the FPC board 510 to other circuit elements. When the lens module is applied to an electronic device, the connector 520 is electrically connected to a main board of the electronic device, so that information transmission between the lens module and other components in the electronic device is realized, and image information of the lens module is transmitted to the electronic device. Specifically, the connector 520 may be a gold finger connector.

It should be noted that, in the present embodiment, the wire bonding process is performed after the FPC board 510 is mounted on the molding layer 350, so that the electrical connection between the photosensitive chip 200, the functional element and the FPC board 510 can be realized in the same electrical connection step. In other embodiments, when the FPC board is mounted after the photosensitive chip and the functional element are electrically connected, another wire bonding process is correspondingly performed to electrically connect the FPC board and the photosensitive chip.

Fig. 10 and 11 are schematic structural diagrams corresponding to steps in another embodiment of the method for packaging the camera module according to the present invention.

The same parts of this embodiment as those of the first embodiment will not be described herein again. The present embodiment is different from the first embodiment in that: after the molding layer 350a is formed, the molding layer 350a covers the carrier substrate 320a, the photosensitive chip 200a and the functional element (not labeled), and exposes the optical filter 400 a.

In this embodiment, the molding layer 350a covers the photosensitive chip 200a and the functional element, so that the influence of the thickness difference between the photosensitive chip 200a and the functional element on the forming process of the molding layer 350a is reduced.

Correspondingly, as shown in fig. 10, the exposed area of the optical filter 400a is a plastic package area i, an area in the plastic package area i higher than the tops of the photosensitive chip 200a and the functional elements is a top plastic package area ii, and the remaining area is a bottom plastic package area i; and when the plastic package material is sprayed to the plastic package area I, the plastic package material is sprayed to the top plastic package area ii and the bottom plastic package area i.

In this embodiment, since the top surfaces of the photosensitive chip 200a and the functional element are higher than the top surface of the carrier substrate 320a, in order to improve the flatness of the top surface of the finally formed plastic package layer 350a, after the bottom plastic package region i is filled with the plastic package material, plastic package is sprayed to the top plastic package region ii.

Specifically, referring to fig. 10, a photosensitive unit and a functional element (not labeled) are temporarily bonded on a carrier substrate 320a, the photosensitive unit includes a photosensitive chip 200a temporarily bonded on the carrier substrate 320a and a filter 400a attached on the photosensitive chip 200a, and pads of the photosensitive chip 200a and the functional element are both opposite to the carrier substrate 320 a.

With reference to fig. 10, a selective spraying process is performed to spray a plastic package material to the plastic package region i, and the plastic package material is cured to form a plastic package layer 350a located in the plastic package region i, where the plastic package layer 350a covers the carrier substrate 320a, the photosensitive chip 200a, and the functional element (not shown), and also covers the sidewall of the optical filter 400 a.

The plastic packaging layer 350a covers the side wall of the optical filter 400a, so that the sealing performance of the cavity in the photosensitive unit is improved, the probability of water vapor, oxidizing gas and the like entering the cavity is reduced, and the performance of the photosensitive chip 200a is guaranteed.

Specifically, when the plastic package material is sprayed to the bottom plastic package area i, when the photosensitive chip 200a and the bearing substrate 320a exposed by the functional element move to the position below the spray head, the spray head sprays the plastic package material, and when the photosensitive unit and the functional element move to the position below the spray head, the spray head stops spraying the plastic package material; and after the plastic packaging material is filled in the bottom plastic packaging area i, when the top plastic packaging area ii moves to the position below the spray head, the spray head sprays the plastic packaging material to the area.

Accordingly, in order to reduce the stress of the molding layer 350a on the optical filter 400a, before forming the molding layer 350a, the method further includes: a stress buffer layer 420a is formed on a sidewall of the filter 400 a.

In this embodiment, the stress buffering layer 420a is made of epoxy glue. Epoxy glue (epoxy resin adhesive) has various forms, and materials with different elastic moduli can be obtained by changing the components of the epoxy resin glue, so that the stress on the optical filter 400a can be regulated and controlled according to actual conditions.

With reference to fig. 10, a redistribution layer (RDL) structure 360a is formed on a side of the molding layer 350a close to the optical filter 400a to electrically connect the bonding pads of the photo-sensing chip 200a and the bonding pads of the functional device (not shown).

In this embodiment, the molding layer 350a covers the photosensitive chip 200a and the functional element, and therefore, the rewiring structure 360a includes: the conductive pillar 362a is located in the plastic package layer 350a and electrically connected to the pad of the photosensitive chip 200a and the pad of the functional device; the interconnection line 361a is located on the molding layer 350a and connected to the conductive pillar 362 a.

Referring to fig. 11, after the rewiring structure 360a is formed, a debonding process is performed to remove the carrier substrate 320a (shown in fig. 10).

For a specific description of the packaging method in this embodiment, reference may be made to the corresponding description in the foregoing embodiments, and details are not repeated here.

Fig. 12 and 13 are schematic structural diagrams corresponding to respective steps in still another embodiment of the method for packaging a camera module according to the present invention.

The same parts of this embodiment as those of the first embodiment will not be described herein again. The present embodiment is different from the first embodiment in that: the re-wiring structure 360b is used to electrically connect the photosensitive chip 200b and a functional element (not labeled).

Referring to fig. 12, after the photosensitive chip 200b and the functional element are temporarily bonded on the carrier substrate 320b, both the pads of the photosensitive chip 200b and the pads of the functional element face away from the carrier substrate 320 b; after the molding layer 350b is formed on the carrier substrate 320b, the molding layer 350b is filled between the photosensitive chip 200b and the functional element.

For this reason, with continued reference to fig. 12, a redistribution structure 360b is formed on the molding layer 350b near the filter 400 b.

In this embodiment, the step of forming the rewiring structure 360b includes: forming conductive bumps 365b on the pads of the photo-sensing chip 200b and the functional device, respectively; the interconnection line 361b is bonded to the conductive bump 365b, and the interconnection line 361b and the conductive bump 365b constitute the re-routing structure 360 b.

The conductive bump 365b protrudes from the surface of the photosensitive chip 200b and the functional element, which is beneficial to improving the electrical connection reliability of each bonding pad and the interconnection line 361 b. In this embodiment, the conductive bump 365b is formed by a ball-mounting process.

Referring to fig. 13, after the rewiring structure 360b is formed, a debonding process is performed to remove the carrier substrate 320b (as shown in fig. 12).

The same parts of this embodiment as those of the second embodiment will not be described herein again. The present embodiment is different from the second embodiment in that: a redistribution structure 360c is formed on the side of the molding layer 350c opposite to the filter 400 c.

Specifically, referring to fig. 14, after the photosensitive chip 200c and the functional device (not labeled) are temporarily bonded on the first carrier substrate 320c, the pad of the photosensitive chip 200c faces away from the first carrier substrate 320c, and the pad of the functional device faces toward the first carrier substrate 320 c.

With continued reference to fig. 14, a molding layer 350c is formed, wherein the molding layer 350c covers the photosensitive chip 200c and the functional elements (not labeled), and also covers the sidewalls of the optical filter 400 c.

Referring to fig. 15, after the plastic encapsulation layer 350c is formed, a debonding process is performed to remove the first carrier substrate 320 c; after the first carrier substrate 320c is removed, the molding layer 350c is bonded to the second carrier substrate 330c away from the surface of the photosensitive chip 200 c.

With reference to fig. 15, after the molding layer 350c is bonded to the second carrier substrate 330c away from the surface of the photo chip 200c, a conductive pillar 280c is formed in the photo chip 200c and electrically connected to the pad of the photo chip 200 c; an interconnection line 361c is formed on a surface of the molding compound layer 350c facing away from the second carrier substrate 330c, and electrically connects a pad of the functional device (not labeled) and the conductive pillar 280c, and the interconnection line 361c and the conductive pillar 280c constitute a redistribution structure 360 c.

In other embodiments, after the photo chip 200 is temporarily bonded to the first carrier substrate, the conductive pillar can be omitted when the pad of the photo chip also faces the first carrier substrate.

Referring to fig. 16, after the rewiring structure 360c is formed, a debonding process is performed to remove the second carrier substrate 330c (as shown in fig. 15).

Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method of packaging a camera assembly, comprising:

providing a bearing substrate, and temporarily bonding a photosensitive unit and a functional element on the bearing substrate, wherein the photosensitive unit comprises a photosensitive chip temporarily bonded on the bearing substrate and a light filter attached on the photosensitive chip, at least the exposed areas of the photosensitive chip and the functional element are plastic package areas, the photosensitive chip and the functional element are provided with welding pads, and the welding pads are back to the bearing substrate; or the welding pad of the photosensitive chip faces away from the bearing substrate, and the welding pad of the functional element faces towards the bearing substrate; or the welding pads face the bearing substrate;

carrying out selective spraying treatment, spraying a plastic packaging material to the plastic packaging area, and carrying out curing treatment on the plastic packaging material to form a plastic packaging layer positioned in the plastic packaging area, wherein the plastic packaging layer is at least filled between the photosensitive chip and the functional element;

and after the plastic packaging layer is formed, electrically connecting the welding pad of the photosensitive chip and the welding pad of the functional element, performing bonding removal treatment, and removing the bearing substrate.

2. The packaging method according to claim 1, wherein the exposed areas of the photosensitive chip and the functional element are the plastic package areas;

or the exposed area of the optical filter is the plastic package area, the area in the plastic package area, which is higher than the tops of the photosensitive chip and the functional element, is a top plastic package area, and the rest area is a bottom plastic package area.

3. The packaging method according to claim 2, wherein after the bottom molding region is filled with the molding compound, the molding compound is sprayed to the top molding region.

4. The packaging method of claim 1, wherein a wire bonding process is used to form wires electrically connecting the pads.

5. The packaging method according to claim 4, wherein the pads are all facing away from the carrier substrate;

in the step of forming the plastic packaging layer, the plastic packaging layer is filled between the photosensitive chip and the functional element;

and performing the lead bonding process on one side of the plastic packaging layer close to the optical filter.

6. The encapsulation method of claim 1, wherein the selective spray coating process comprises: providing a movable spray head;

and the spray head is adopted to move above the bearing substrate, and when the spray head moves to pass through the upper part of the plastic packaging area, the spray head sprays plastic packaging materials to the plastic packaging area.

7. The packaging method according to claim 6, wherein the nozzle moves at least twice over the same molding region to form the molding layer; and the moving path of the sprayer when the sprayer moves above the plastic package area for the previous time has a first direction, the moving path of the sprayer when the sprayer moves above the same plastic package area for the next time has a second direction, and the second direction is different from the first direction.

8. The packaging method according to claim 6 or 7, wherein the arrangement direction of the photosensitive chips and the functional elements on the carrier substrate is an X direction, and a direction parallel to the surface of the carrier substrate and perpendicular to the X direction is a Y direction; the moving path of the spray head has a direction including: one or more of + X direction, -X direction, + Y direction, and-Y direction.

9. The encapsulation method of claim 8, wherein the path of travel of the nozzle head has a direction further comprising: an oblique direction at 45 degrees to the X direction or an oblique direction at 45 degrees to the Y direction.

10. The packaging method according to claim 6, wherein before the selective spray coating process, position information of the plastic package region is acquired; and performing the selective spraying treatment based on the acquired position information.

11. The packaging method according to claim 10, wherein the step of obtaining the position information of the plastic package region comprises: placing the photosensitive unit and the functional element above the bearing substrate based on preset position information, and taking the preset position information as the position information of the plastic packaging area;

or after the photosensitive unit and the functional element are arranged above the bearing substrate, the surface of the bearing substrate is irradiated by light, and the light information reflected by the surface of the bearing substrate is collected to obtain the position information of the plastic package area.

12. The encapsulation method according to claim 10, wherein the step of performing the selective spray coating process based on the acquired position information includes: the real-time position of the spray head on the bearing substrate is obtained in real time while the spray head moves above the bearing substrate; and controlling the spray head to spray plastic package material to the plastic package area in the process of moving on the bearing substrate based on the real-time position and the acquired position information.

13. The packaging method according to claim 6, wherein the vertical distance between the nozzle and the carrier substrate is 5mm to 30mm, the nozzle moves at a speed of 0.01m/s to 0.1m/s, and the nozzle sprays the molding compound at a flow rate of 1ml/s to 10 ml/s.

14. The encapsulation method of claim 1, wherein the step of selectively spraying comprises: providing a spray head and a movable carrying platform;

after the temporary bonding step, the bearing substrate is placed on the movable carrier platform, the bearing substrate is made to move below the spray head, and when the plastic packaging area moves to the position below the spray head, the spray head sprays plastic packaging materials to the plastic packaging area.

15. The encapsulation method according to claim 1, wherein the curing process is performed after the selective spray coating process is finished.

16. The method of packaging of claim 15, further comprising, prior to performing the curing process: and in the process of carrying out the selective spraying treatment, heating the plastic packaging material positioned in the plastic packaging area, wherein the process temperature of the heating treatment is lower than that of the curing treatment.

17. The packaging method according to claim 16, wherein the process temperature of the heat treatment is in a range of 20 ℃ to 120 ℃; the process temperature range of the curing treatment is 120 ℃ to 160 ℃.

18. The packaging method according to claim 4, wherein after the wire bonding process, a de-bonding process is performed to remove the carrier substrate;

or, after forming the molding compound layer and before the wire bonding process, the method further includes: and performing bonding removal treatment to remove the bearing substrate.