KR101187899B1 - Image sensor module and camera module comprising the same and manufacturing method for the same - Google Patents

Abstract

The present invention relates to an image sensor module and a camera module having the same, and more particularly, to an image sensor module incorporating an image pickup device in a printed circuit board and a camera module having the same.

The present invention provides an image pickup device including an image pickup area for converting incident light energy into an electrical signal; And a printed circuit board on which the image pickup device is embedded, wherein the printed circuit board includes: a first layer having a light transmitting region formed therein and coupled to the image pickup device on a bottom surface thereof, and at least one inside thereof to accommodate the image pickup device; Provided is an image sensor module including a second layer in which a through hole is formed.

Image Sensor Module, Camera Module

Description

An image sensor module and a camera module having the same and a method of manufacturing the same {Image sensor module and camera module comprising the same and manufacturing method for the same}

1 and 2 are cross-sectional views showing a conventional camera module.

3 is a perspective view showing the structure of a camera module according to an embodiment of the present invention.

4 is a cross-sectional view of the camera module of FIG. 3.

5 is a cross-sectional view illustrating a structure of an image sensor module included in the camera module of FIG. 3.

6 is a flowchart illustrating a method of manufacturing an image sensor module and a camera module having the same, according to an exemplary embodiment.

FIG. 7 is a diagram illustrating each step of performing a method of manufacturing the image sensor module of FIG. 6 and a camera module having the same.

<Explanation of symbols for the main parts of the drawings>

100: camera module 110: image sensor module

111: printed circuit board 112: image pickup device

113: bump ball 114: adhesive member

115: IR filter 116: pad

117: base substrate 118: external connection member

120: optical system

The present invention relates to an image sensor module and a camera module having the same, and more particularly, to an image sensor module incorporating an image pickup device in a printed circuit board and a camera module having the same.

The camera module is a device capable of capturing and transmitting video and pictures, and is used in mobile phones, notebook computers, PDAs, cameras for inserting monitors, rear view cameras for bumper mounting, and cameras for door / interphones.

In general, the camera module is composed of an image sensor module consisting of an image pickup device and a substrate and an optical system consisting of a lens. As an interconnection type between the image pickup device and the substrate, a wire bonding type and a flip chip type are used.

1 and 2 are cross-sectional views showing the configuration of a conventional camera module. 1 is a cross-sectional view showing the interconnection between the image pickup device and the printed circuit board in the form of wire bonding, and FIG. 2 is a cross-sectional view showing the interconnection between the image pickup device and the printed circuit board in flip chip bonding. It is a cross section.

As shown in FIGS. 1 and 2, the camera module 10, 20 includes an image sensor module 11, 21, a housing 17, a lens assembly 19, and an IR-filter 16. .

The image sensor modules 11 and 21 include printed circuit boards 12 and 22 and imaging devices 13 and 23. The coupling between the imaging devices 13, 23 and the printed circuit board 12, 22 may be made by wire bonding electrically connected using the gold wire 14 as shown in FIG. It may be combined by flip chip bonding formed by forming bumps 24 as shown in FIG.

On the other hand, the housing 17 has a lens assembly 19 in the front, the lens assembly 19 includes one or more lenses 18, inside the housing 17, that is, behind the lens assembly 19 IR-filter 16 is disposed.

In general, after manufacturing the image sensor modules 11 and 21, various types of lenses and housings are disposed in the image sensor module to manufacture a camera module.

However, the conventional camera module shown in FIG. 1 mounts an image sensor chip on a printed circuit board (PCB) or a lead frame, and electrically connects the pad of the chip and the connection pad of the substrate using wire bonding. It is produced by connecting. However, such a conventional package method by wire bonding has difficulty in thinning the package thickness due to the loop height of the wire (the distance from the surface of the chip to which the wire is bonded) to the maximum height of the wire to be bonded.

In addition, passive elements are mounted on the printed circuit board according to the electrical characteristics of the chip for the image sensor. In the conventional camera module structure by wire bonding, an additional area must be secured by the area and thickness of the passive elements installed on the substrate. do. Therefore, the width and thickness of the substrate also have to be increased in response to the size of the passive element, thereby increasing the size of the camera module.

Meanwhile, a flip chip package may be used as another method for implementing a small and thin camera module as shown in FIG. 2. In the above-described package method by wire bonding in FIG. 1, a chip on board (COB) method for mounting an image sensor chip on a hard printed circuit board (HPCB) is mainly used. In contrast, the chip on film (COF) method is used in the flip chip package method. The chip on film method is a method of mounting a chip for an image sensor on a flexible printed circuit board (FPCB).

Such a flip chip package method is a technique used to implement a thin camera module compared to the wire bonding method, but there is a limit in significantly reducing the thickness of the camera module. In other words, since the chip for the image sensor and the printed circuit board are sequentially stacked in the camera module by the flip chip package method, it is impossible to implement a camera module thinner than the thickness of each of the image sensor chip and the printed circuit board.

Recently, due to the complexity of circuits and the increasing demand for high density and miniaturized circuits, a multi-layered board having multiple layers of wires has been used. As a result, the thickness of the printed circuit board is further increased, and the overall thickness of the camera module is also increased. To overcome such technical limitations, a technology for manufacturing the camera module thinner is required.

An object of the present invention is to provide an image sensor module and a camera module having the same that can significantly reduce the thickness of the camera module in accordance with the trend of miniaturization and thinning of the device on which the camera module is mounted.

The present invention provides an image pickup device including an image pickup area for converting incident light energy into an electrical signal; And a printed circuit board on which the image pickup device is embedded, wherein the printed circuit board includes: a first layer having a light transmitting region formed therein and coupled to the image pickup device on a bottom surface thereof, and at least one inside thereof to accommodate the image pickup device; Provided is an image sensor module including a second layer in which a through hole is formed.

In the present invention, the second layer and a third layer for supporting the image pickup device may be further coupled to a surface of the second layer that faces the surface on which the first layer is formed.

In the present invention, an IR filter may be formed in the light transmitting region formed in the first layer.

In the present invention, the printed circuit board and the image pickup device may be coupled by flip chip bonding.

In the present invention, an image signal processor may be further embedded in the printed circuit board.

According to another aspect of the present invention, there is provided an image sensor module having the above structure; And an optical system coupled to the image sensor module at an upper side of the image sensor module and receiving an external image to form an image in the imaging area.

According to another aspect of the present invention, there is provided a method of forming a light transmitting region in a first layer of a printed circuit board; Coupling an imaging device to a bottom of the light transmitting region; And combining a second layer having at least one through hole formed under the first layer to accommodate the image pickup device.

In the present invention, the method of manufacturing the image sensor module may further include coupling an IR filter to the light transmitting region.

In the present invention, the step of coupling the image pickup device to the bottom of the light transmission region, the bump ball is formed on one side of the image pickup device, the pad is formed on one side of the light transmission region, the bump ball and Bonding the pads by flip chip bonding.

In the present invention, the method of manufacturing the image sensor module may further include embedding an image signal processor in the printed circuit board.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

3 is a perspective view illustrating a structure of a camera module according to an embodiment of the present invention, FIG. 4 is a cross-sectional view of the camera module of FIG. 3, and FIG. 5 illustrates a structure of an image sensor module provided in the camera module of FIG. 3. It is a cross section.

3 to 5, the camera module 100 includes an image sensor module 110 and an optical system 120.

The image sensor module 110 includes a printed circuit board 111, an imaging device 112, a bump ball 113, an adhesive member 114, an IR filter 115, and a pad 116.

The printed circuit board 111 may be formed by sequentially stacking at least two printed circuit boards. As the printed circuit board 111 of each layer, a hard printed circuit board (HPCB) or a flexible printed circuit board (FPCB) may be used.

Here, the present invention is characterized in that the imaging device 112 is embedded in the printed circuit board 111. In detail, in the camera module illustrated in FIG. 1, the image pickup device is configured to be separately coupled to the upper side of the printed circuit board. The IR filter was coupled to one side of the optical system coupled to the printed circuit board and the image pickup device. In such a conventional camera module, there is a problem in that the overall thickness of the image sensor module is increased by the thickness of each of the printed circuit board and the image pickup device. In addition, since the distance between the image sensor module and the IR filter is required separately, there is a problem that the overall thickness of the image sensor module becomes thicker as the distance between the image sensor module and the IR filter. In order to solve such a problem, the present invention provides an image sensor module that the image module and the IR filter is embedded in the printed circuit board, the overall thickness of the camera module is significantly reduced.

Looking at the process in which the image pickup device 112 is embedded in the printed circuit board 111, first, a light transmitting region 111a_1 is formed at the center of the first layer 111a that forms the uppermost layer of the printed circuit board 111. . In addition, the imaging device 112 is mounted on the periphery of the first layer 111a where the light transmitting region 111a_1 is formed. Here, the light transmitting region 111a_1 may be formed by a general press process or the like. The light transmitting region 111a_1 may be formed to be smaller than the image pickup device 112, and thus the image pickup device 112 may be prevented from being separated through the light transmission region 111a_1.

In addition, the imaging device 112 is coupled to the lower side of the first layer 111a where the light transmitting region 111a_1 is formed, that is, to the inner side of the printed circuit board 111. The coupling of the printed circuit board 111 and the imaging device 112 may be performed by a flip chip method for connecting the pad 116 and the bump ball 113.

Here, the bump device 113 is provided in the imaging device 112, and the pad 116 is provided in the printed circuit board 111. The bump ball 113 and the pad 116 electrically connect the image pickup device 112 and the printed circuit board 111 and physically fix the bump ball 113 and the pad 116. Here, the adhesive member 114 may be used for coupling between the imaging device 112 and the printed circuit board 111. As the adhesive member 114, a non conductive paste (NCP), a non conductive film (NCF), an anisotropic conductive film (ACF), or an anisotropic conductive paste (ACP) may be used.

Alternatively, the method of directly bonding the printed circuit board 111 to the prepared image pickup device 112 may be possible. In some cases, the bonding may be implemented by a wire bonding method. It may not be different from the camera module.

In addition, the second layer 111b and the third layer 111c are sequentially joined to the lower side of the first layer 111a to form the printed circuit board 111, thereby forming an image pickup device (i.e., an inside of the printed circuit board 111). 112 may be embedded. Here, the through hole 111b_3 may be formed in the center of the second layer 111b to accommodate the image pickup device 112. Here, the bonding between the first layer 111a, the second layer 111b, and the third layer 111c may be performed by hot press in a vacuum as in a manufacturing process of a general printed circuit board.

The imaging device 112 includes an imaging area 112a that converts incident light energy into an electrical signal. Such an image pickup device 112 is disposed inside the printed circuit board 111 as described above.

The imaging device 112 is a semiconductor device that converts optical information into an electrical signal. A CCD (Charge Coupled Device) image sensor or a Complementary Metal Oxide Semiconductor (CMOS) image sensor may be used. In order to reduce the thickness of the camera module by miniaturization and multifunction of the camera phone, it is preferable to use a CMOS image sensor suitable for using a chip on film (COF) method. However, the protection scope of the present invention is not necessarily limited thereto.

The IR filter 115 may be disposed in the light transmitting region 111a_1 of the printed circuit board 111.

In detail, the IR filter 115 serves to block light in the infrared region among the light passing through the lens 123. The photodiode (not shown) used in the imaging region 112a of the imaging device 112 transmits to the infrared region. The infrared ray transmitted through the photodiode makes the image appear red, thereby preventing the phenomenon of the IR filter 115. Is used. To this end, an IR-cut coating is formed on the top surface of the IR filter 115. In addition, the IR filter 115 serves to prevent the light incident therein from being reflected. To this end, an anti-reflective coating is formed on the lower surface of the IR filter 115 to prevent reflection. The IR filter 115 is mounted on the lower surface of the opening of the housing in the conventional camera module. However, in the camera module 100 according to the present invention, the IR filter 115 is mounted on the image sensor module 110 as described above. Therefore, since it is not necessary to separately provide a space for mounting the infrared filter in the housing, it is advantageous to miniaturize the camera module. The IR filter 115 may be coupled to the printed circuit board 111 by UV bonding or the like. Since the IR filter 115 has a dimension tolerance of the light transmitting region 111a_1 of the printed circuit board 111 and a dimension tolerance of the IR filter 115, the IR filter 115 is bonded to the printed circuit board 111. The IR filter 115 is held in a floating state, and is bonded by applying a UV adhesive between the light transmitting region 111a_1 and the IR filter 115.

Meanwhile, as shown in FIG. 4, a separate base substrate 117 may be further formed below the printed circuit board 111. The base substrate 117 may have an extension part 117a extending to at least one side, and one end of the extension part 117a may be a connector or a socket connected to an external circuit. The external connection member 118 may be further formed.

Meanwhile, although not shown in the drawing, a passive element such as a capacitor may be mounted on the front surface of the printed circuit board 111. In addition, an image signal processor (ISP) may be further included on the rear surface of the printed circuit board 111. The image processing processor may be mounted on one surface of the printed circuit board 111 as in the conventional camera module process. Or it may be possible to be built in the printed circuit board 111, such as the imaging device 112 described above. That is, the through hole may be formed in at least one layer constituting the printed circuit board 111 to accommodate the image processing processor in the printed circuit board 111.

On the other hand, although not shown in the drawing, a via hole is formed in the printed circuit board 111 and a connection terminal penetrating therein is disposed, and as necessary, a connection between the various connection terminals or the printed circuit board 111 is performed. This allows the connection of the connection terminals to be connected to the passive element installed in the). In addition to the connection between the terminals described here as an example, various three-dimensional circuit configurations are possible as necessary.

Meanwhile, the optical system 120 includes a lens housing 121, a protective cover 122, and a lens 123. The protective cover 122 may support the lens housing 121 and block light from entering an unwanted path from the outside. The protective cover 122 is formed with an opening through which the lens housing 121 is inserted. The protective cover 122 may perform a function of protecting the imaging device 112. The lens housing 121 includes at least one lens 123 and is installed in the opening of the protective cover 122.

By such a configuration, the overall size of the camera module 100 can be reduced to have an effect of miniaturizing and thinning the device on which the camera module is mounted. In other words, in the conventional camera module, the printed circuit board and the image pickup device are formed in separate layers, so that a space equal to the sum of the thicknesses of the printed circuit board and the image pickup device is required. In order to solve such a problem, in the present invention, the image sensor module may be incorporated in the printed circuit board, thereby reducing the overall size of the image sensor module.

In addition, the IR filter 115 is formed to be embedded in the printed circuit board 111, so that a separate space for securing a gap between the IR filter and the image pickup device is unnecessary in the optical system 120, thereby providing a camera module 100. ) The overall height is further reduced.

Hereinafter, an image sensor module and a manufacturing method of a camera module having the same according to an embodiment of the present invention will be described.

6 is a flowchart illustrating a method of manufacturing an image sensor module and a camera module having the same according to an embodiment of the present invention, and FIGS. 7A to 7G illustrate a method of manufacturing the image sensor module of FIG. 6 and a camera module having the same. Figures show each step performed.

6 and 7, an image sensor module and a method of manufacturing a camera module including the same according to an embodiment of the present invention may include a light transmitting region 111a_1 on a first layer 111a of a printed circuit board 111. Forming (S210), coupling the image pickup device 112 to one side of the first layer 111a on which the light transmitting region 111a_1 is formed (S220), and the printed circuit board 111 Forming a through hole 111b_3 in the second layer 111b of step (S230), and bonding each layer of the printed circuit board 111 to each other (step S240).

FIG. 7A illustrates a step (S210) of forming the light transmitting region 111a_1 in the first layer 111a of the printed circuit board 111. As shown in FIG. 7A, a light transmitting region 111a_1 on which the imaging device 112 is mounted is formed at the center of the first layer 111a constituting the uppermost layer of the printed circuit board 111. Here, the light transmitting region 111a_1 may be formed by a general press process or the like.

FIG. 7B is a view illustrating a step (S220) of coupling the image pickup device 112 to one side of the first layer 111a on which the light transmitting region 111a_1 is formed, and FIG. 7C is a first layer 111a. Is a view showing a state in which coupling of the image pickup device 112 is completed. As shown in FIGS. 7B and 7C, the pad provided in the printed circuit board 111 in a state in which the rear surface of the first layer 111a on which the light transmitting region 111a_1 is formed is turned upward. The printed circuit board 111 and the imaging device 112 are flip chip bonded using the bump ball 113 provided in the 116 and the imaging device 112. Here, the bump ball 113 provided in the imaging device 112 may be made of gold, or the outer surface may be made of nickel plated with gold. Here, the adhesive member 114 may be used for coupling between the imaging device 112 and the printed circuit board 111. As the adhesive member 114, a non conductive paste (NCP), a non conductive film (NCF), an anisotropic conductive film (ACF), or an anisotropic conductive paste (ACP) may be used.

In detail, as electronic products are miniaturized and highly functional, semiconductor chips, which form a core part of electronic products, are also becoming highly integrated and high performance. In the manufacture of semiconductor packages that protect such highly integrated and high-performance semiconductor chips from dust, moisture, or various external environments such as electrical and mechanical loads, the trend toward thin and short and multi-pinning is strengthened. have. Therefore, the semiconductor package method is also difficult to cope with the trend of thin and short and multi-pin with the existing wire bonding method, and a variety of new ways to solve this problem are being sought. The method is a solder bump method.

In the solder bump method, a separate solder bump is formed on a pad, which is an input / output terminal of a semiconductor chip, and then the semiconductor chip is inverted and directly attached to a circuit pattern of a carrier substrate or a circuit tape. In this way, it is referred to as 'flip chip bonding' because the semiconductor chip is bonded upside down.

The flip chip bonding method is largely classified into a thermocompression method and a laser compression method. In the case of the thermocompression bonding method, the semiconductor chip needs to be heated for a long time due to the high heat loss at the heat transfer site that appears when the semiconductor chip is heated. On the other hand, the laser crimping method is a method in which the solder bumps of the semiconductor chip are moved to the bond position so as to face the designated solder bumps of the substrate and then pressurized while heating the semiconductor chip from the rear surface of the semiconductor chip, and the semiconductor chip is heated using a laser. .

Meanwhile, as shown in FIG. 7C, the IR filter 115 may be disposed in the light transmitting region 111a_1 of the printed circuit board 111. The IR filter 115 may be coupled to the printed circuit board 111 by UV bonding or the like. In the camera module 100 according to the present invention, the IR filter 115 is embedded in the image sensor module 110. Therefore, since it is not necessary to separately provide a space for mounting the infrared filter in the housing, the effect of miniaturizing the camera module can be obtained.

FIG. 7D illustrates a step (S230) of forming the through hole 111b_3 in the second layer 111b of the printed circuit board 111. As shown in FIG. 7D, a through hole 111b_3 may be formed in the center of the second layer 111b of the printed circuit board 111 to accommodate the image pickup device 112. Here, the through hole 111b_3 may be formed by a general press process or the like. The second layer 111b of the printed circuit board 111 may be formed by combining two or more layers 111b_1 and 111b_2 again. Although FIG. 7D illustrates that the second layer 111b is composed of two layers 111b_1 and 111b_2, the spirit of the present invention is not limited thereto, and the second layer 111b may be configured according to the specifications and usage environment of the camera module. Various modifications of the shape of the laminated structure constituting 111b) are possible.

7E is a diagram illustrating a step of forming the third layer 111c of the printed circuit board 111. The third layer 111c of the printed circuit board 111 may serve as a base member to which the imaging device 112 coupled to the first layer 111a is seated, and the second layer 111b is coupled. . As shown in FIG. 7E, the third layer 111c of the printed circuit board 111 may be formed by combining two or more layers 111c_1 and 111c_2 again. Although FIG. 7E illustrates that the third layer 111c is composed of two layers 111c_1 and 111c_2, the spirit of the present invention is not limited thereto, and the third layer 111c may be configured according to the specifications of the camera module and the environment of use. Various modifications of the shape of the laminated structure constituting 111c) are possible.

FIG. 7F is a diagram illustrating a step of combining the layers of the printed circuit board 111 with each other (step S240), and FIG. 7G is a diagram illustrating a step of combining the layers of the printed circuit board 111. As shown in FIGS. 7F and 7G, the second layer 111b having the through hole 111b_3 formed on the third layer 111c is combined. The first layer 111a to which the imaging device 112 is coupled is coupled to the upper portion of the second layer 111b. Here, the imaging device 112 may be accommodated in the through hole 111b_3 of the second layer 111b. In addition, the bonding between the first layer 111a, the second layer 111b, and the third layer 111c may be performed by hot press in a vacuum as in a manufacturing process of a general printed circuit board.

By such a configuration, by embedding the image pickup device inside the printed circuit board, the overall size of the camera module 100 can be reduced to have an effect of miniaturizing and thinning the device on which the camera module is mounted. In addition, since the image pickup device is incorporated in the printed circuit board, it is possible to obtain an effect of preventing the image pickup device from being damaged from an external impact.

The present invention can achieve the effect of reducing the thickness and size of the camera module in accordance with the trend of miniaturization and thinning of the device on which the camera module is mounted.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (10)

An imaging device having an imaging area for converting incident light energy into an electrical signal; And A printed circuit board on which the image pickup device is embedded, The printed circuit board, A first printed circuit board layer and a second printed circuit board layer formed to be stacked, The first printed circuit board layer, A first printed circuit board layer having an image pickup device coupled to a bottom surface thereof, and having a light transmitting area formed above the image pickup device so that light is incident on the image pickup area of the image pickup device; The second printed circuit board layer, And a through hole formed therein so that the image pickup device coupled to the lower surface of the first printed circuit board layer is accommodated when the first printed circuit board layer is stacked on the upper surface of the first printed circuit board layer. The method of claim 1, The second printed circuit board layer and an image sensor module are further coupled to a surface of the second printed circuit board layer opposite to a surface on which the first printed circuit board layer is formed. . Claim 3 has been abandoned due to the setting registration fee. The method of claim 1, And an IR filter in a light transmitting region formed in the first printed circuit board layer. Claim 4 has been abandoned due to the setting registration fee. The method of claim 1, And the printed circuit board and the image pickup device are coupled by flip chip bonding. Claim 5 was abandoned upon payment of a set-up fee. The method of claim 1, The image sensor module further includes an image signal processor in the printed circuit board. Claim 6 has been abandoned due to the setting registration fee. An image sensor module having the structure of any one of claims 1 to 5; And And an optical system coupled to the image sensor module at an upper side of the image sensor module and receiving an external image to form an image in the imaging area. Forming a light transmitting region in the first printed circuit board layer; The imaging device is disposed below the light transmission area of the first printed circuit board layer so that light passing through the light transmission area is incident on the imaging area of the imaging device, and the imaging device is placed on the first printed circuit board. Bonding to the bottom surface of the layer; And Coupling the first printed circuit board layer to an upper surface of the second printed circuit board layer having a through hole formed therein, When the first printed circuit board layer is combined with the second printed circuit board layer, the imaging device coupled to the bottom surface of the first printed circuit board layer is received in the through hole of the second printed circuit board layer. Method of manufacturing an image sensor module, characterized in that. Claim 8 was abandoned when the registration fee was paid. The method of claim 7, wherein The manufacturing method of the image sensor module, Coupling an IR filter to the light transmitting region. The method of claim 7, wherein Coupling the imaging device to the bottom of the light transmitting region, And a bump ball formed on one side of the image pickup device, and a pad formed on one side of the light transmitting region, thereby coupling the bump ball and the pad by flip chip bonding. Claim 10 has been abandoned due to the setting registration fee. The method of claim 7, wherein The manufacturing method of the image sensor module, And embedding an image signal processor in the printed circuit board.

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