JP2011072015A - Camera module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera module which can be reduced in size and can obtain high focusing accuracy. <P>SOLUTION: This camera module includes a lens 11, a barrel 12 for supporting the lens 11, an image sensor chip 2 in which imaging is performed by a sensor 21 based on light incident via the lens 11 and an imaging signal is outputted, and a wiring board 5 including a window. The barrel 12 is fixed to a surface of the wiring board 5. The image sensor chip 2 is then fixed to a surface of the wiring board 5 opposed to the surface to which the barrel 12 is fixed so as to position the sensor 21 in the window of the wiring board 5. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a camera module, and more particularly to a camera module including a lens, a lens barrel that supports the lens, and an image sensor chip.

  Camera modules are widely used for applications such as cellular phones, portable terminals (PDAs) and card cameras. An example of the structure of a conventional camera module is shown in FIG. As shown in FIG. 15, the camera module has a package 108 in which an image sensor chip 106 is accommodated on a substrate 104, and is fixed by solder 103. A cover glass 105 is provided on the top of the package 108 so that light can enter from the top.

  The lens 101 is supported by a lens barrel 102 that surrounds the package 108. The lens barrel 102 has a cylindrical configuration and is composed of two members. The two members constituting the lens barrel 102 are relatively movable, and the distance between the lens 101 and the image sensor chip 106 can be changed for focus adjustment.

  Here, camera modules used for mobile phones and the like are required to be further downsized as mobile phones and the like are downsized. However, since the conventional camera module has a configuration as shown in FIG. 15, it is difficult to reduce the size.

  Further, in the conventional camera module, the configuration for determining the path length between the lens 101 and the image sensor chip 106 includes the lens 101, two members constituting the lens barrel 102, the substrate 104, the package 108, and the image sensor chip 106. Therefore, the dimensional error of each component and the error due to their mutual connection are accumulated. Accordingly, the variation in path length between the lens 101 and the image sensor chip 106 is large, and the focus accuracy is low.

  As described above, the conventional camera module has a problem that it is difficult to meet the demand for downsizing and the focus accuracy is low.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a camera module that can be reduced in size and has high focusing accuracy.

  A camera module according to the present invention includes a lens, a lens barrel that supports the lens, an image sensor chip that captures an image by a sensor unit based on light incident through the lens, and outputs an imaging signal, and a window unit. And the lens barrel is fixed on a first surface of the wiring board, and the image sensor chip includes a first wiring board so that a sensor portion is positioned at a window portion of the wiring board. It is fixed on the second surface opposite to the first surface. With such a configuration, the size can be reduced and the focusing accuracy can be increased.

  Another camera module according to the present invention includes a lens, a lens barrel that supports the lens, an image sensor chip that captures an image by a sensor unit based on light incident through the lens, and outputs an imaging signal. The lens barrel is fixed to the first substrate, and the image sensor chip is fixed to a surface opposite to the surface of the first substrate on which the lens barrel is fixed. It is what. With such a configuration, the size can be reduced and the focusing accuracy can be increased.

  The camera module further includes a wiring substrate having a window portion, and the image sensor chip has a sensor portion exposed from the window portion on a surface opposite to a surface of the first substrate on which the lens barrel is fixed. In such a state, it may be fixed via the wiring board.

  The image sensor chip and the wiring board or the first board may be electrically connected through a spacer. With such a configuration, the distance between the image sensor chip and the wiring board can be made constant, and the distance between the lens and the image sensor chip can be made constant.

  Here, the image sensor chip may be provided with a CSP rewiring layer so as to avoid the image sensor portion. The image sensor chip and the wiring board may be electrically connected by solder bumps. Furthermore, the image sensor chip and the wiring board may be electrically connected by an anisotropic conductive material.

  According to the present invention, it is possible to provide a camera module that can be miniaturized and has high focusing accuracy.

1 is a structural diagram of a camera module according to an embodiment of the present invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. It is a perspective view of the camera module concerning an embodiment of the invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. It is sectional drawing which shows a part of camera module concerning embodiment of this invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. It is a flowchart which shows the manufacturing method of the camera module concerning embodiment of this invention. It is a flowchart which shows the manufacturing method of the camera module concerning embodiment of this invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. 1 is a structural diagram of a camera module according to an embodiment of the present invention. It is a structural diagram of a conventional camera module.

Embodiment 1 of the Invention
FIG. 1 is a structural diagram showing main parts of a camera module according to Embodiment 1 of the invention. This camera module includes a lens unit 1 and an image sensor chip 2. Here, the lens unit 1 includes a lens 11 and a lens barrel 12. In this example, the lens 11 is an aspherical convex lens and has a function of forming an image of incident light on the surface of the image sensor chip 2. The lens barrel 12 has a cylindrical shape, and supports the lens 11 at a predetermined position on the inner periphery thereof.

  The image sensor chip 2 includes a sensor unit 21, a logic circuit unit 22, and a bonding pad 23. The sensor unit 21 is an element that is formed on the surface of the image sensor chip 2 and converts optical information into an electrical signal and outputs it as an imaging signal. This element has a large number of read pixels. The sensor unit 21 is, for example, a CCD element or a CMOS element. The logic circuit unit 22 performs various signal processing such as amplification processing and noise removal processing on the electric signal output from the sensor unit 21. The bonding pad 23 is an input / output terminal electrically connected to the logic circuit unit 22. The bonding pad 23 is electrically connected to an external electrode by wire bonding.

  The lens barrel 12 is fixed on the logic circuit portion 22 of the image sensor chip 2. The lens barrel 12 and the image sensor chip 2 are bonded by, for example, an ultraviolet curable resin. In this case, the lens barrel 12 is mounted on the image sensor chip 2 at a predetermined position, and thereafter, an ultraviolet curable resin is applied so that the image sensor chip 2 and the lens barrel 12 are bonded. Alternatively, after the ultraviolet curable resin is applied to one or both of the image sensor chip 2 and the lens barrel 12, both may be positioned. The image sensor chip 2 and the lens barrel 12 are bonded and fixed by irradiating the ultraviolet curable resin with ultraviolet rays.

  In this manner, by placing the lens barrel 12 on the logic circuit unit 22, it is possible to effectively utilize the area above the logic circuit unit 22 that is not normally used. In particular, it is presumed that the sensor unit 21 and the logic circuit unit 22 will be further integrated into one chip in the future, so the value of this technology that uses the area above the logic circuit unit 22 is high.

  As described above, in the camera module shown in FIG. 1, since the lens barrel that supports the lens is directly fixed on the image sensor chip, the camera module can be reduced in size. Since the member between the lens and the image sensor chip is only the lens barrel, there is little stacking error, and the relative positions of the two can be accurately fixed.

Embodiment 2 of the Invention
Next, the configuration of another camera module according to the second embodiment of the invention will be described with reference to FIG. The configuration shown in FIG. 2 includes a CSP (Chip Size Package) rewiring layer 3. The CSP rewiring layer 3 includes an optical window, and the lens barrel 12 is bonded and fixed on the image sensor chip 2 at the optical window. The CSP rewiring layer 3 has a plurality of solder bumps 31 provided thereon. The solder bumps 31 are electrically connected to the logic circuit unit 22 provided on the image sensor chip 2 by copper wiring or the like.

  The camera module shown in FIG. 2 can also be reduced in size because the lens barrel is directly fixed on the image sensor chip in the same manner as the configuration shown in FIG. Since the member between the lens and the image sensor chip is only the lens barrel, there is little stacking error, and the relative positions of the two can be accurately fixed.

  A camera module according to Embodiment 2 of the present invention will be further described with reference to FIG. This camera module is configured at the wafer 3a level. In other words, the lens barrel 12 that supports the lens 11 is fixed to the wafer 3a before the chip is cut. At this time, the lens barrel 12 needs to be fixed at an accurate position on the wafer 3a, and is fixed using a robot in order to alleviate the impact when the two come into contact with each other. Thereafter, the wafer 3a is cut into a chip size.

Embodiment 3 of the Invention
FIG. 4 shows a configuration of a camera module according to the third embodiment of the invention. A camera module according to a third embodiment of the present invention includes a lens unit 2 and an image sensor chip 2 and a multilayer wiring board 5. The wiring substrate 5 is made of, for example, polyester or polyimide, and is wired with copper or the like. And the wiring board 5 concerning this embodiment has a window part especially.

  The camera module having the same configuration as that of the second embodiment of the invention is fixed to the wiring board 5 by the underfill 7 in a state where the lens barrel is inserted into the window portion of the wiring board 5. This underfill 7 is a resin sealant.

  An external electrode is provided around the window portion of the wiring board 5 at a position corresponding to the solder bump 31 of the CSP rewiring layer 3. Therefore, the camera module according to the second embodiment of the present invention is inserted into the window portion of the wiring board 5, and the solder bump 31 and the external electrode of the wiring board 5 are in electrical contact by heat treatment or the like.

  Other chips such as a DSP (Digital Signal Processor) chip 6 are also mounted on the wiring board 5 on the same surface as the external electrodes. This DSP chip 6 is also bonded and fixed to the wiring substrate 5 by an underfill 7.

  As described above, since the camera module according to the third embodiment is configured such that the lens barrel is inserted into the window portion of the wiring board, the camera module can be further reduced in size. In addition, if the outer peripheral surface of the lens barrel and the inner peripheral surface of the window portion of the wiring board are in contact with each other, the relative positions of the two are mutually restricted, so that positioning becomes easy.

Embodiment 4 of the Invention
FIG. 5 is a diagram showing a configuration of a camera module according to the fourth embodiment of the invention. Similar to the camera module according to the third embodiment of the present invention, this camera module includes a wiring board 5 having a window. The lens barrel 12 of the lens unit 1 is fixed on the logic circuit unit 22 on the upper surface of the image sensor chip 2. In this example, the lens barrel 12 and the wiring board 5 are fixed by an underfill 7. The underfill 7 may be provided over the entire circumference of the lens barrel 12 or may be a part thereof. This camera module has a CSP rewiring layer 3.

  In the camera module according to the present embodiment, for example, after fixing the image sensor chip 2 to the wiring board 5, the lens barrel 12 is placed on the image sensor chip 2, and the underfill 7 is used to wire the lens barrel 12. The substrate 5 may be fixed. Alternatively, after fixing the lens barrel 12 on the image sensor chip 2, the lens barrel 12 and the wiring substrate 5 may be fixed by the underfill 7 by being inserted into the window portion of the wiring substrate 5 from below.

  Further, the configuration of the camera module will be described in detail with reference to FIG. The image sensor chip 2 of this camera module is provided on the lower surface of the wiring board 5 together with the DSP chip 6 and is covered with a sealing resin 8.

  As for the electrical connection between the image sensor chip 2 and the wiring board 5, there are a plurality of methods as shown in FIG. For example, there are a method of printing a solder gold bump 91 on a pad on the upper surface of the image sensor chip 2, a method of using an anisotropic conductive material 92, and a method of using a solder bump in the rewiring layer 3.

  Further, as shown in FIG. 7, a spacer may be provided between the image sensor chip 2 and the wiring board 5. With this configuration, the distance between the image sensor chip 2 and the wiring substrate 5 can be made constant, and the distance between the lens 11 and the image sensor chip 2 can be made constant.

  As described above, since the camera module according to the fourth embodiment is configured such that the lens barrel is inserted into the window portion of the wiring board, the camera module can be further reduced in size. In addition, if the outer peripheral surface of the lens barrel and the inner peripheral surface of the window portion of the wiring board are in contact with each other, the relative positions of the two are mutually restricted, so that positioning becomes easy.

Embodiment 5 of the Invention
FIG. 8 is a diagram showing a configuration of a camera module according to the fifth embodiment of the invention. In the camera module according to this example, the window provided on the wiring board 5 is smaller than the lens barrel 12 as shown in the figure. Therefore, the lens barrel 12 is fixed to the upper surface of the wiring board 5, not the image sensor chip 2. However, if the lens barrel 12 can be fixed to the upper surface of the wiring substrate 5, the window portion does not have to be smaller than the lens barrel 12. The lens barrel 12 and the image sensor chip 2 are fixed by the underfill 7. The image sensor chip 2 is bonded and fixed to the wiring board 5 on the surface opposite to the surface on which the lens barrel 12 is fixed. The image sensor chip 2 is fixed to the wiring substrate 5 at a position where the sensor unit 21 is exposed from the window portion of the wiring substrate 5.

  As for the electrical connection between the image sensor chip 2 and the wiring board 5, as shown in FIG. 6, a method of printing solder gold bumps 91 on the pads on the upper surface of the image sensor chip 2 and an anisotropic conductive material 92 are used. Either a method or a method using solder bumps for the rewiring layer 3 may be used. Further, as shown in FIG. 7, a spacer 94 may be provided between the image sensor chip 2 and the wiring board 5. Even if the solder bump 91 is melted by heating, the distance between the image sensor chip 2 and the wiring board 5 can be made constant by the spacer 94. Therefore, the distance between the lens 11 and the image sensor chip 2 can be made constant.

  As described above, since the camera module according to the fifth embodiment is configured to fix the lens barrel and the image sensor chip via the wiring board, the camera module can be reduced in size.

Embodiment 6 of the Invention
9 and 10 are diagrams showing the configuration of a camera module according to Embodiment 6 of the invention. The configuration diagram shown in FIG. 10 is an enlarged view of a part of the configuration diagram shown in FIG. 9 and shows the configuration in detail. This camera module is characterized in that a glass substrate 10 is provided between the lens barrel 12 and the image sensor chip 2. A wiring layer 52 is provided on the glass substrate 10. Here, the glass substrate 10 may not be made of glass as long as it is a substrate made of a transparent or translucent transparent material. Hereinafter, the glass substrate in other embodiment is also the same.

  The lens barrel 12 is bonded and fixed to the upper surface of the glass substrate 10. The image sensor chip 2 is bonded and fixed to the lower surface of the glass substrate 10. The wiring layer 52 of the glass substrate 10 is wired so as not to block incident light to the sensor unit 21 of the image sensor chip 2.

  In this camera module, incident external light is refracted by the lens 11, passes through the glass substrate 10, and enters the sensor unit 21 on the image sensor chip 2.

  Since the camera module according to the sixth embodiment has the above-described configuration, it can be reduced in size. Furthermore, since the sensor unit 21 of the image sensor chip 2 is covered by the glass substrate, it is possible to prevent foreign matters such as dust and dust from entering the sensor unit 21 and to prevent deterioration in image quality. it can.

  A method for forming the glass substrate 10 and the image sensor chip 2 will be described in detail with reference to FIGS.

  First, as shown in FIG. 11A, a glass plate 10 having a nickel plating 1201 on the surface is prepared. The nickel plating 1201 is not provided in a portion where the sensor unit 21 of the image sensor chip 2 is located.

  Next, as illustrated in FIG. 11B, a first insulating layer 1203 having a first opening 1203 a is formed on the nickel plating 1201. The first insulating layer 1203 is formed by uniformly applying a photosensitive resin on the surface of the nickel plating 1201, exposing the portion corresponding to the first opening 1203a of the photosensitive resin, and developing the exposed portion by a development process. This can be done by removing.

  Next, as shown in FIG. 11C, a first wiring layer 1204 is formed on the surface of the nickel plating 1201. The first wiring layer 1204 is formed by sputtering a power supply film made of an alloy of chromium and copper on the first insulating layer 1203 and in the first opening 1203a, and then uniformly applying a photoresist film on the power supply film. Then, the photoresist film is exposed to the pattern of the first wiring layer 1204, the exposed portion is removed by development processing, and then the power feeding film is energized to electroform copper or copper alloy, and then an unnecessary photoresist film and This can be done by removing the power supply film.

  Next, as shown in FIG. 11D, a second insulating layer 1205 having a second opening 1205a with a required pattern is formed on the surface of the first insulating layer 1203 and the surface of the first wiring layer 1204. Form. The second insulating layer 1205 is formed by uniformly applying a photosensitive resin to the surface of the first insulating layer 1203 and the surface of the first wiring layer 1204, and then exposing a portion corresponding to the second opening 1205a. This can be done by removing the exposed portion by development processing. At this stage, the image sensor chip 2 and other electronic components 1211 are connected to the first wiring layer 1204, and the connection portion between the image sensor chip 2, electronic components 1211 and the first wiring layer 1204 is resin-molded. Thus, the module 12 can also be manufactured.

  Next, as shown in FIG. 11E, a second wiring layer 1206 is formed on the second insulating layer 1205, and a connection portion 1206a is formed in the second opening 1205a. The second wiring layer 1206 and the connecting portion 1206a are formed by sputtering a power supply film made of an alloy of chromium and copper on the second insulating layer 1205 and in the second opening 1205a, and then forming a photoresist film on the power supply film. The photoresist film is exposed to the pattern of the second wiring layer 1206 and the exposed portion is removed by a development process, and then the power feeding film is energized to electroform an alloy of copper and nickel, This can be done by removing unnecessary photoresist film and power supply film.

  Next, as shown in FIG. 11F, a third insulating layer in which a third opening 1207a is formed in a predetermined pattern on the surface of the second wiring layer 1206, the connecting portion 1206a, and the second insulating layer 1205. 1207 is formed. The third insulating layer 1207 is formed by uniformly applying a photosensitive resin to the surfaces of the second wiring layer 1206, the connecting portion 1206a, and the second insulating layer 1205, and then exposing a portion corresponding to the third opening 1207a. This exposure portion can be removed by development processing.

  Next, as shown in FIG. 12A, the second wiring layer 1206 and the image sensor chip 2 are connected, and the second wiring layer 1206 and the electronic component 1211 are connected. The second wiring layer 1206 and the image sensor chip 2 are connected after the gold bump 1209 formed on the pad portion of the image sensor chip 2 is inserted into the third opening 1207a provided in the third insulating layer 1207. This can be done by applying required heat and pressure between the two wiring layers 1206 and the image sensor chip 2. In addition, the connection between the second wiring layer 1206 and the electronic component 1211 is such that the terminal portions of the second wiring layer 1206 and the electronic component 1211 are opposed to each other via the solder 1208 inserted into the third opening 1207a. This can be done by applying the required heat between the layer 1206 and the electronic component 1211.

  Next, as shown in FIG. 12B, the image sensor chip 2, the electronic component 1211, and a connection portion between these and the second wiring layer 1206 are molded with a molding resin.

  In addition, since it is necessary to ensure the path | route through which light passes between the image sensor chip 2 and the glass substrate 10, it is preferable that an insulating layer and a wiring layer do not exist. For this purpose, as described above, it is possible to secure the optical path by removing only the window portion serving as the optical path from the insulating layer and the wiring layer formed between the image sensor chip 2 and the glass substrate 10. In addition, the window portion serving as the optical path may be masked to form a layer so that an insulating layer and a wiring layer are not generated. The window portion may be a space where nothing is filled, but may be filled with a transparent resin or the like.

Embodiment 7 of the Invention
FIG. 13 is a diagram showing a configuration of a camera module according to the seventh embodiment of the invention. This camera module is characterized in that a glass substrate 10 is provided between the wiring substrate 5 and the lens barrel 12. The glass substrate 10 may not be made of glass as long as it is made of a transparent or translucent transparent material. Hereinafter, the glass substrate in other embodiment is also the same.

  The lens barrel 12 is bonded and fixed to the upper surface of the glass substrate 10. The wiring board 5 is fixed to the lower surface of the glass substrate 10. Further, the wiring board 5 and the image sensor chip 2 are fixed. The wiring board 5 has a window portion, and is fixed to the image sensor chip 2 at a position where the sensor portion 21 of the image sensor chip 2 is exposed from the window portion.

  In this camera module, incident external light passes through the lens 11 and then passes through the glass substrate 10 and enters the sensor unit 21 on the image sensor chip 2.

  Since the camera module according to the seventh embodiment has the above-described configuration, it can be reduced in size. Furthermore, since the sensor unit 21 of the image sensor chip 2 is covered by the glass substrate, it is possible to prevent foreign matters such as dust and dust from entering the sensor unit 21 and to prevent deterioration in image quality. it can.

Embodiment 8 of the Invention
FIG. 14 is a diagram showing a configuration of a camera module according to the eighth embodiment of the invention. This camera module includes a glass substrate 10 between the wiring substrate 5 and the lens barrel 12 as in the camera module according to the seventh embodiment of the invention. Further, the camera module has a spacer 94 between the wiring board 5 and the image sensor chip 2, and the wiring board 5 and the image sensor chip 2 are electrically contacted by an anisotropic conductive material 92. ing.

  The lens barrel 12 is bonded and fixed to the upper surface of the glass substrate 10. The wiring board 4 is fixed to the lower surface of the glass substrate 10. Further, the wiring board 5 and the image sensor chip 2 are fixed. The wiring board 5 has a window portion, and is fixed to the image sensor chip 2 at a position where the sensor portion 21 of the image sensor chip 2 is exposed from the window portion.

  In this camera module, incident external light passes through the lens 11 and then passes through the glass substrate 10 and enters the sensor unit 21 on the image sensor chip 2.

  Since the camera module according to the eighth embodiment has the above-described configuration, it can be reduced in size. Furthermore, since the sensor unit 21 of the image sensor chip 2 is covered by the glass substrate, it is possible to prevent foreign matters such as dust and dust from entering the sensor unit 21 and to prevent deterioration in image quality. it can.

  Since the spacer is provided between the image sensor chip 2 and the wiring substrate 5, the distance between the image sensor chip 2 and the wiring substrate 5 can be made constant, and the distance between the lens 11 and the image sensor chip 2 can be made constant. can do.

DESCRIPTION OF SYMBOLS 1 Lens part 2 Image sensor chip 11 Lens 12 Lens barrel 21 Sensor part 5 Wiring board

Claims (8)

A lens part having a lens and a lens support part for supporting the lens;
On one surface side, a sensor unit that receives light incident through the lens unit, a plurality of input / output terminals that are connected to external electrodes by wire bonding outside the sensor unit, the sensor unit and the input unit An image sensor chip that has a logic circuit formation region between output terminals and processes an imaging signal based on light received by the sensor unit;
In the camera module with
The lens module is mounted on the one surface of the image sensor chip and fixed on the one surface of the image sensor chip.   The lower end portion of the lens support portion placed on the one surface of the image sensor chip is outside the sensor portion and the input / output terminal so that the region above the logic circuit formation region is utilized. The camera module according to claim 1, wherein the camera module is mounted inside and fixed on the one surface of the image sensor chip.   3. The camera module according to claim 1, wherein a lower end portion of the lens support portion placed on the one surface of the image sensor chip is disposed on the logic circuit formation region.   The camera module according to any one of claims 1 to 3, wherein the lens unit and the image sensor chip are fixed by an adhesive. A lens part having a lens and a lens support part for supporting the lens;
On one surface side, a sensor unit that receives light incident through the lens unit, a plurality of input / output terminals that are connected to external electrodes by wire bonding outside the sensor unit, the sensor unit and the input unit An image sensor chip that has a logic circuit formation region between output terminals and processes an imaging signal based on light received by the sensor unit;
In the camera module with
The lens support unit is placed on the one surface of the image sensor chip, and supports the lens at a predetermined position so as to form an image of light incident on the lens on the surface of the image sensor chip. The camera module.   The lower end portion of the lens unit placed on the one surface of the image sensor chip is outside the sensor unit and inside the input / output terminal so that an area above the logic circuit formation area is utilized. The camera module according to claim 5, wherein the camera module is mounted on the camera module.   The camera module according to claim 5, wherein a lower end portion of the lens unit placed on the one surface of the image sensor chip is disposed on the logic circuit formation region.   The lower end portion of the lens unit placed on the one surface of the image sensor chip is disposed inside the outer periphery of the image sensor chip, and is fixed on the one surface of the image sensor chip. 6. The camera module according to claim 1 or 5, characterized in that:

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