JP2007110594A - Camera module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera module which can be miniaturized and with high reliability using a lens member in which a lens and a lens support part which supports the lens are integrally formed. <P>SOLUTION: The camera module 1 has an image sensor chip 20 which converts incident light into a video signal and a lens mold 10 which condenses the incident light on the image sensor chip 20 and the lens mold has a lens 10a which condenses the incident light on the image sensor chip 20 and a leg part 10b integrally constituted with the lens 10a and having length approximately equivalent to focal distance of the lens 10a. The leg part 10b is adhered to the image sensor chip 20 by adhesives 30 and an adhesion groove 40 to be a guide of the adhesives 30 is formed on its adhesion surface. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a camera module, and more particularly to a camera module including a lens, a leg portion 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. FIG. 7 shows an example of the structure of a conventional camera module described in Patent Document 1. As shown in FIG. 7, in the camera module, a package 208 in which an image sensor chip 206 is accommodated is placed on a substrate 204 and fixed by solder 203. A cover glass 205 is provided on the top of the package 208 so that light can enter from the top.

  The lens 201 is supported by a lens barrel 202 that surrounds the package 208. That is, the lens barrel 202 functions as a lens support portion. The lens barrel 202 has a cylindrical configuration and is composed of two members. The two members constituting the lens barrel 202 are relatively movable, and the distance between the lens 201 and the image sensor chip 206 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. 7, it has been difficult to reduce the size.

  Further, in the conventional camera module, the configuration for determining the path length between the lens 201 and the image sensor chip 206 includes a lens 201, two members constituting the lens barrel 202, a substrate 204, a package 208, and an image sensor chip 206. 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 201 and the image sensor chip 206 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.

  In order to solve such a problem, Patent Document 1 discloses a camera module shown in FIG. The camera module includes a lens unit 101 and an image sensor chip 102. Here, the lens unit 101 includes a lens 111 and a lens barrel 112. The lens 111 has a function of forming incident light on the surface of the image sensor chip 102. The lens barrel 112 has a cylindrical shape, a rectangular shape, or the like, and supports the lens 111 at a predetermined position on the inner periphery thereof.

  The image sensor chip 102 includes a sensor unit 121, a logic circuit unit 122, and a bonding pad 123. The sensor unit 121 is an element that is formed on the surface of the image sensor chip 102 and converts optical information into an electrical signal and outputs it as an imaging signal. The sensor unit 121 is, for example, a CCD element or a CMOS element. The logic circuit unit 122 performs various signal processing such as amplification processing and noise removal processing on the electrical signal output from the sensor unit 121. The bonding pad 123 is an input / output terminal that is electrically connected to the logic circuit unit 122. The bonding pad 123 is electrically connected to an external electrode by wire bonding.

  The lens barrel 112 is fixed on the logic circuit unit 122 of the image sensor chip 102. The lens barrel 112 and the image sensor chip 102 are bonded with, for example, an ultraviolet curable resin. In this case, the lens barrel 112 is placed at a predetermined position on the image sensor chip 102, and then an ultraviolet curable resin is applied so that the image sensor chip 102 and the lens barrel 112 are bonded. Alternatively, after either or both of the image sensor chip 102 and the lens barrel 112 are coated with an ultraviolet curable resin, the positioning may be performed. The image sensor chip and the lens barrel are bonded and fixed by irradiating the ultraviolet curable resin with ultraviolet rays.

As described above, in the camera module shown in FIG. 8, since the lens unit 101 having the lens support unit 112 that supports the lens 111 is directly fixed on the image sensor chip 102, the size can be reduced. Since the member between the lens 111 and the image sensor chip 102 is only the lens support portion 112, there is little stacking error, and the relative position of both can be accurately fixed.
WO03 / 015400 pamphlet

  However, in the conventional camera module shown in FIG. 8 described above, the adhesive surface of the lens support 112 is flush, and the adhesive that fixes the lens barrel 112 and the image sensor chip 102 is applied from the side. Or to be applied to the lower surface. In recent years, as the size of image sensor chips has been reduced, it is expected that when the adhesive is applied as described above, the length of protrusion (the amount of protrusion) of the adhesive in the XY axis direction is increased. If the protruding adhesive covers the upper surface of the light receiving surface 121 or the bonding pad 123, the incident light cannot be received well, and the reliability of the camera module is deteriorated due to the risk of electrical signal insulation. There is a problem.

  The present invention has been made to solve such problems, and can be reduced in size and reliability by using a lens member in which a lens and a lens support portion for supporting the lens are integrally formed. An object of the present invention is to provide a high camera module.

  In order to achieve the above-described object, a camera module according to the present invention includes an image sensor chip that converts incident light into a video signal, and a lens member that focuses the incident light on the image sensor chip. The lens member includes a lens for condensing the incident light on the image sensor chip, and a leg portion integrally formed with the lens, and the leg portion is bonded to the image sensor chip with an adhesive. An adhesive groove serving as a guide for the adhesive is formed.

  In the present invention, since the adhesive groove serving as an adhesive guide is formed in the leg portion of the lens member, the protruding length of the adhesive in the XY axis direction can be suppressed.

  Moreover, it is preferable that the said leg part has the length substantially equivalent to the focal distance of the said lens. If the length of the leg is the same as the focal length of the lens, the focal length can be adjusted only by installing the leg on the image sensor chip.

  Furthermore, the said leg part is formed around the said lens, Comprising: The said adhesion groove | channel shall be provided in the inner periphery and / or outer peripheral side of the said leg part.

  Furthermore, the adhesive groove may be provided at substantially the center of the bottom surface of the leg that is bonded to the image sensor.

  Here, the adhesive groove is formed on a part of the bottom surface of the leg portion to be bonded to the image sensor, and at least a part of the bottom surface except the adhesive groove is in contact with the image sensor chip. can do. By bringing a part other than the adhesive groove directly into contact with the image sensor, it is possible to accurately adjust the focus.

  In this case, the image sensor chip includes a light receiving unit that converts the incident light into a video signal through the lens, a logic circuit that processes the video signal, and a video signal processed by the logic circuit to the outside. An output electrode part, and at least a part of the bottom surface of the leg part is in contact with the logic circuit. The space above the logic circuit can be used effectively by bringing the leg portion into contact with the logic circuit.

  In addition, the lens member may be configured such that the adhesive is interposed between the leg portion and the image sensor chip, and the focal length of the lens is adjusted by the adhesive. In the case where it is difficult to take out the lens, an adhesive is interposed between the leg portion and the image sensor chip, and this adhesive absorbs manufacturing tolerances of the lens member and enables focus adjustment.

  In this case, the image sensor chip includes a light receiving unit that converts the incident light into a video signal through the lens, a logic circuit that processes the video signal, and a video signal processed by the logic circuit to the outside. The lens member may be adhered on the logic circuit of the image sensor chip. The space above the logic circuit can be used effectively by bringing the leg portion into contact with the logic circuit.

  According to the present invention, since the protruding length of the adhesive in the XY axis direction can be suppressed, the chip size of the image sensor can be reduced. Therefore, it is possible to provide a small camera module.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. In this embodiment, the present invention is applied to a camera module that can be miniaturized.

Embodiment 1 FIG.
First, the camera module according to the first embodiment of the present invention will be described. FIG. 1 is a diagram showing main parts of a camera module according to Embodiment 1 of the present invention. The camera module 1 includes a lens mold 10 as a lens member in which a lens 10a and a leg portion 10b are integrated, and an image sensor chip 20.

  The lens 10 a has a function of forming incident light on the surface of the image sensor chip 20. The lens 10a is made of, for example, plastic or glass. The leg portion 10b is formed in a circular or square cylindrical shape when viewed from above, and supports the lens 10a at a predetermined position on the inner periphery thereof. Here, the leg part 10b does not necessarily need to be configured in a cylindrical shape. For example, the lens may be supported by a single point or a plurality of points. The lens 10a and the leg 10b are integrally formed, for example, made of a glass mold. A plurality of lenses 10a may be mounted on the optical path.

  Further, an adhesive groove 40 that can accommodate an adhesive 30 for fixing the leg portion 10b and the image sensor chip 20 is formed on the lower surface of the leg portion 10b, that is, the adhesive surface with the image sensor chip 20. In the present embodiment, the adhesive groove 40 is formed on the outer peripheral side of the bottom surface of the leg portion. However, the adhesive groove may be located at any position such as the inner periphery and the center portion. There may also be two or more locations. Any shape that can guide the adhesive 30 by the adhesive groove 40 and suppress the protrusion from the leg portion 10b may be used.

  For example, when the distance between the leg portion 10b and the sensor portion 22 is short and the probability that the adhesive 30 protrudes to the upper surface of the sensor portion 22 is high, the adhesive groove 40 is formed on the outer peripheral side of the leg portion 10b as in this example. By forming, this can be prevented. On the other hand, when the distance between the leg 10b and the electrode pad 24 is short and there is a high probability that the adhesive 30 will flow onto the upper surface of the electrode pad 24, an adhesive groove is provided on the inner peripheral side of the leg 10b. Just do it. Further, the position of the adhesive groove can be varied depending on the place where the leg portion 10b is disposed. Furthermore, in the case where an adhesive is partially applied to the bottom surface of the leg 10b, it is only necessary to provide an adhesive groove only in the region to be applied.

  The image sensor chip 20 includes a sensor unit 22, a logic circuit unit 23, and an electrode pad 24 on a substrate 21. The sensor unit 22 is an element that is formed on the surface of the image sensor chip 20 and converts optical information into an electrical signal and outputs it as an imaging signal. This element has a large number of read pixels. Here, the image sensor chip 20 only has to process the imaging signal based on the light incident through the lens 10a, and does not need to output the imaging signal itself. For example, the image sensor chip 20 recognizes a change in the image by comparing the imaging signal with a predetermined signal or by comparing with an imaging signal obtained by past imaging, and indicates whether or not the image has changed. May be configured to output only the signal.

  The sensor unit 22 is, for example, a CCD element or a CMOS element. The logic circuit unit 23 performs various signal processing such as amplification processing and noise removal processing on the electrical signal output from the sensor unit 22.

  The electrode pad 24 is an input / output terminal electrically connected to the logic circuit unit 23. The electrode pad 24 is electrically connected to an external electrode (not shown) by wire bonding. For example, the image sensor chip 20 is installed on a wiring board constituting a mobile phone, a portable terminal (PDA) or a card camera, and the electrode pad 24 and the wiring board are electrically connected by wire bonding. Further, the image sensor chip 20 is installed on a sub-wiring board on which passive parts such as resistors and capacitors, active parts such as transistors and LSIs are mounted, and the electrode pad 24 and the sub-wiring board are electrically connected by wire bonding. The sub-wiring board can be electrically connected to a mobile phone, a portable terminal (PDA) or a card camera. Alternatively, flip chip mounting may be used.

  The leg portion 10b is fixed on the logic circuit 23 of the image sensor chip 20 via a surface protective film. By fixing the leg portion 10b on the logic circuit 23 via a surface protective film, the area above the logic circuit 23 can be used effectively, and the camera module 1 can be downsized. The leg 10b and the image sensor chip 20 are bonded by, for example, an ultraviolet curable resin, a thermosetting resin, or a mixed resin thereof. For example, when bonding using an ultraviolet curable resin, the leg part 10b is mounted in a predetermined position with respect to the image sensor chip 20, and then the image sensor chip 20 and the leg part 10b are bonded. UV curable resin is applied as shown in FIG. Or you may make it position both, after apply | coating an ultraviolet curable resin to either one or both of an image sensor chip or a leg part. Then, the image sensor chip 20 and the leg portion 10b are bonded and fixed by irradiating the ultraviolet curable resin with ultraviolet rays.

  When bonding, the length of the leg portion 10b in the Z direction can be increased by contacting the image sensor chip 20 at a portion other than the bonding groove 40 of the leg portion 10b and applying the adhesive 30 to the bonding groove 40. By matching with the focal length of the lens, the focal length can be adjusted with a deviation of the molding error of the lens mold 10. Further, as will be described later, an adhesive 30 may be applied between the leg 10 b and the image sensor chip 20, and the focal length may be adjusted by the thickness of the adhesive 30. In any case, the protruding length of the adhesive 30 in the XY direction can be suppressed by accommodating the adhesive 30 in the adhesive groove 40, and the sensor unit 22 (light receiving surface) and electrodes of the image sensor chip 20 can be suppressed. An effect of preventing the adhesive from entering the pad 24 can be obtained.

  Next, the effect in this Embodiment is demonstrated. 2 and 3 are diagrams for explaining the effects of the present embodiment. The connection between the camera module according to the present embodiment and the leg portion of the conventional camera module and the image sensor chip is enlarged. FIG.

  In any of the camera modules, an example is shown in which the leg is brought into contact with the image sensor chip. As shown in FIG. 2, the focus can be adjusted with high accuracy by bringing the leg 10 b into contact with the image sensor chip 20. The adhesive 30 is accommodated in the adhesive groove 40 so that the protruding length of the adhesive 30 in the XY direction is suppressed, and the adhesive 30 can be converged to the electrode pad 24 without entering.

  On the other hand, as shown in FIG. 3, when the adhesive 140 is applied after the leg 10b is brought into contact with the image sensor chip 20, when the chip size of the image sensor chip 20 is small, the leg 10b and the electrode Since the distance from the pad 24 cannot be made large, the adhesive 140 enters the formation region of the electrode pad 24.

  In the present embodiment, in the camera module 1 that is brought into contact with the image sensor chip 20 and fixed by the adhesive 30, an adhesive groove 40 that guides the adhesive 30 is provided in a part of the adhesive surface of the leg 10 b. Thus, the protrusion length of the adhesive 30 in the XY direction can be reduced. Therefore, the adhesive 30 does not protrude beyond the region that can be bonded, that is, the electrode pad 24, the light receiving surface 22, and the like. Even if the chip size of the image sensor chip 20 is reduced by the adhesive groove 40, the penetration of the adhesive into the light receiving surface 22 and the electrode pad 24 of the image sensor chip 20 can be suppressed, and the reliability is high even if the chip size is reduced. The camera module 1 can be obtained, and the size of the entire camera module can be reduced.

  Furthermore, the leg portion 10b can be brought into direct contact with the image sensor chip 20, and the focus of the lens 10a can be adjusted depending on the accuracy of the lens mold 10. That is, since the adhesive groove 40 is used to make a part of the leg 10b abut on the image sensor chip 20, the adhesive 30 does not exist between the lens mold 10 and the image sensor chip 20, so the lens Only the molding error 10a can be used as the focal length error. Therefore, steps such as focus adjustment can be reduced, which can contribute to high productivity.

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described. The camera module according to this embodiment adjusts the focal length with an adhesive that adheres the legs to the image sensor chip, so that the focal length can be adjusted with high precision even when it is difficult to adjust the focus only with the accuracy of the lens mold. To do. FIG. 4 is an enlarged view showing a connection portion between the leg portion of the camera module and the image sensor chip according to the present embodiment. In the leg portion 10b of the camera module according to the present embodiment, an adhesive groove 40b is formed on the inner peripheral side in addition to the adhesive groove 40a formed on the outer peripheral side. Further, an adhesive 30 is interposed between the leg portion 10 b and the image sensor chip 20, and unlike the first embodiment, the leg portion 10 b is not in contact with the image sensor chip 20. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  In this way, by allowing the adhesive 30 to exist between the leg 10b and the image sensor chip 20, the adhesive 30 functions to adjust the focal length of the lens 10a according to its thickness. Therefore, when it is difficult to adjust the focal length with the accuracy of the lens mold 10, this can be adjusted by the thickness of the adhesive 30. Even in this case, the adhesive grooves 40a and 40b can prevent the adhesive 30 from protruding from the electrode pad 24 of the adhesive 30 and the upper surface of the sensor unit 22.

  FIG. 5 is a diagram showing a modification of the present embodiment. As shown in FIG. 5, an adhesive groove 40c may be formed at the center of the leg 10b. Also in this case, the adhesive 30 can be accommodated in the adhesive groove 40c, and the spread of the adhesive 30 in the surface direction can be suppressed.

  On the other hand, when there is no adhesive groove, as shown in FIG. 6, the amount of the adhesive 130 protruding in the XY direction increases, and the adhesive 130 enters the electrode pad 24 and the light receiving surface 22. I'm stuck.

  In the present embodiment, even when the leg portion 10b and the image sensor chip 20 are close to each other, since there are the adhesive grooves 40a to 40c, the adhesive 30 is accommodated here, and the adhesive in the XY direction is provided. The amount of protrusion is suppressed, and the adhesive 30 can be converged before the electrode pad 24 and the light receiving surface 22. Further, when the focus adjustment is difficult due to the accuracy of the lens mold 10, the optical axis or the focal length can be adjusted by the thickness of the adhesive 30.

  It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the shape, position, and number of adhesive grooves are not limited to the above-described embodiment. Of course, the adhesive grooves in the above-described embodiment may be appropriately combined.

It is a figure which shows the principal part of the camera module concerning Embodiment 1 of this invention. It is a figure which expands and shows the connection part of the leg part of the camera module concerning Embodiment 1 of this invention, and an image sensor chip. It is a figure which expands and shows the connection part of the leg part of a conventional camera module, and an image sensor chip. It is a figure which expands and shows the connection part of the leg part of a camera module concerning Embodiment 2 of this invention, and an image sensor chip. It is a figure which expands and shows the connection part of the leg part and image sensor chip | tip of a camera module concerning the modification of Embodiment 2 of this invention. It is a figure which expands and shows the connection part of the leg part of a conventional camera module, and an image sensor chip. It is a figure which shows the structural example of the conventional camera module described in patent permission document 1. FIG. It is a figure which shows the camera module of patent document 1. FIG.

Explanation of symbols

10a Lens 10 Lens mold 10b Leg part 20 Image sensor chip 21 Substrate 22 Sensor part 22 Light receiving surface 23 Logic circuit part 24 Electrode pad 30 Adhesives 40, 40a, 40b, 40c Adhesive groove

Claims (12)

An image sensor chip for converting incident light into a video signal;
A lens member for condensing the incident light on the image sensor chip,
The lens member includes a lens that condenses the incident light on the image sensor chip, and a leg portion configured integrally with the lens,
The camera module in which the leg is bonded to the image sensor chip with an adhesive, and an adhesive groove serving as a guide for the adhesive is formed. The camera module according to claim 1, wherein the leg portion has a length substantially equal to a focal length of the lens. The leg portion is formed around the lens,
The camera module according to claim 1, wherein the adhesive groove is provided on an inner periphery and / or an outer periphery side of the leg portion. The camera module according to claim 1, wherein the adhesion groove is provided at a substantially center of a bottom surface of the leg portion to be adhered to the image sensor. The adhesive groove is formed in a part of a bottom surface of the leg portion to be bonded to the image sensor, and at least a part of the bottom surface excluding the adhesive groove is in contact with the image sensor chip. The camera module according to claim 1 or 2. The image sensor chip includes a light receiving unit that converts the incident light into a video signal through the lens, a logic circuit that processes the video signal, and an electrode that outputs the video signal processed by the logic circuit to the outside. And
The camera module according to claim 5, wherein at least a part of the bottom surface of the leg is brought into contact with the logic circuit. The camera module according to claim 6, wherein the logic circuit is provided between the light receiving surface and the electrode portion. The camera module according to claim 1, wherein the adhesive is interposed between the leg portion and the image sensor chip, and a focal length of the lens is adjusted by the adhesive. . The image sensor chip includes a light receiving unit that converts the incident light into a video signal through the lens, a logic circuit that processes the video signal, and an electrode that outputs the video signal processed by the logic circuit to the outside. And
The camera module according to claim 8, wherein the lens member is bonded onto the logic circuit of the image sensor chip. The camera module according to claim 9, wherein the logic circuit is provided between the light receiving surface and the electrode unit. The camera module according to claim 1, wherein the lens member is made of a glass mold. The camera module according to claim 1, wherein the lens member is made of a plastic mold.

Images