JP2007129164A - Module for optical apparatus, method of manufacturing same, and structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a module for optical apparatus which has the structure capable of effectively preventing the damage of its micro-lens in its manufacturing process. <P>SOLUTION: The module 1 for optical apparatus has a solid photographing element 11 provided with an effective pixel region 11a having a micro-lens array 11b, and has a translucent lid 12 having a translucence for covering the effective pixel region 11a. The translucent lid 12 is fastened to the outside region of the effective pixel region 11a in the solid photographing element 11 via a bonding portion 14, and the effective pixel region 11a and the translucent lid 12 are separated from each other. Also, an electrode pad 16 disposed in the outside of the effective pixel region 11a is buried in the bonding portion 14. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical device module mounted as an imaging unit in an optical device, and a method for manufacturing the optical device module.

  2. Description of the Related Art Optical devices such as camera-equipped mobile phones that have been widely used in recent years incorporate a module for an optical device in which a solid-state imaging device and a lens are integrated. Patent Document 1 discloses a module for an optical device built in a camera, that is, a camera module.

  The camera module 100 described in Patent Document 1 will be described with reference to FIG. FIG. 9 is a cross-sectional view showing the structure of the camera module 100.

  As shown in FIG. 9, the camera module 100 includes an image sensor chip 101, a glass support substrate 102, and a lens 103.

  The glass support substrate 102 is bonded and fixed on the light receiving surface 101 a of the image sensor chip 101. The lens 103 is provided on the glass support substrate 102. The light incident on the lens 103 passes through the glass support substrate 102 and is condensed on the image sensor chip 101, and is converted into an electric signal by the photoelectric conversion element formed on the light receiving surface 101a. Here, the glass support substrate 102 supports the thin image sensor chip 101 of about several hundred μm, and the image sensor chip 101 can be easily handled in the manufacturing process.

  As shown in FIG. 9, the camera module 100 further includes an electrode pad 106, a rewiring 107, and a bump electrode 108. The electrode pad 106 is disposed on the surface of the image sensor chip 101 and is connected to an input / output circuit of the image sensor chip 101. A rewiring 107 extending from the back surface of the image sensor chip 101 to the electrode pad 106 is formed. Further, a bump electrode 108 serving as an external connection terminal is formed on a portion of the rewiring 107 exposed on the back surface of the chip.

  Further, as shown in FIG. 9, a filter member 104 is attached to the curved surface of the lens 103. The filter member 104 functions as a filter for blocking incident light in a predetermined wavelength region, specifically, an infrared cut filter or the like. A diaphragm member 105 is disposed on the filter member 104.

As described above, the camera module 100 having a small size and low manufacturing cost is realized by modularizing components such as a lens, an image sensor chip, and a glass support substrate.
JP 2004-226873 A (publication date: August 12, 2004)

  In recent image sensors with high integration of pixels, a microlens array in which fine microlenses are formed in an array is provided in an effective pixel area of an image sensor chip (solid-state image sensor), and a collection of photoelectric conversion elements. It is indispensable to increase lightness.

  However, in the conventional camera module 100, in order to support the image sensor chip 101 of about several hundred μm, the glass support substrate 102 is directly bonded to the light receiving surface of the image sensor chip 101 with an adhesive. Yes. For this reason, when the conventional technique is applied to the image sensor chip 101 having a fine microlens formed on the surface, there is a problem that the microlens is easily damaged in the manufacturing process.

  The above problem will be specifically described as follows.

  In the conventional camera module 100, the glass support substrate 102 is attached to the surface of the image sensor chip 101 with an adhesive in the manufacturing process. For this reason, when the above-described conventional technique is applied to the image sensor chip 101 having a fine microlens formed on the surface, the glass support substrate 102 contacts the microlens and is damaged when the glass support substrate 102 is attached. Problem arises. At this time, the periphery of the microlens formed on the surface of the image sensor chip 101 is filled with the adhesive. For this reason, when the adhesive is solidified, the microlens is also heated, and there is a problem that the microlens is easily damaged by the thermal stress.

  In the conventional camera module 100, the rewiring 107 is provided in the through hole from the back surface to the front surface of the image sensor chip 101. The through hole is usually formed by deep etching from the back surface of the image sensor chip 101. In order to perform this deep etching, it is necessary to polish the back surface of the image sensor chip 101 with the glass support substrate 102 attached to the surface of the image sensor chip 101 to reduce the thickness of the chip. However, when the glass support substrate 102 is held and a mechanical force is applied to the image sensor chip 101 as in the above-described back surface polishing, mechanical stress is applied to the microlens, and this mechanical force is applied. The stress causes damage to the microlens.

  Further, when the above-described conventional technique is applied to the image sensor chip 101 having a fine microlens formed on the surface, the following problems occur at the same time.

  That is, when dust adheres to the glass support substrate 102, the dust casts a shadow on the microlens formed on the surface of the image sensor chip 101, thereby reducing the light condensing property of the photoelectric conversion element. For this reason, there arises a problem that the yield is deteriorated due to an increase in the cost for dust removal in the manufacturing environment or an increase in the defect occurrence rate due to the dust.

  Further, when the above-described conventional technique is applied to the image sensor chip 101 having a fine microlens formed on the surface, the periphery of the microlens is filled with an adhesive as described above. For this reason, the problem that the condensing performance of a micro lens falls compared with the case where a micro lens is used in the air also arises.

  In the conventional camera module 100, a filter member 104 such as an infrared cut filter is attached to the curved surface of the lens 103. For this reason, the filter surface is also curved, and depending on the incident angle of the incident light, there arises a problem that the predetermined filter performance determined at the time of designing the filter is not sufficiently exhibited.

  In the conventional camera module 100, the electrode pad 106 is formed on the front surface of the image sensor chip 101, and the bump electrode 108 connected through the rewiring 107 is formed on the back surface. Has a problem that the image sensor chip 101 is easily damaged by heat or mechanical stress during assembly.

  The present invention has been made in view of the above problems, and an object of the present invention is a small module for an optical device including a solid-state imaging device including a microlens on a photoelectric conversion device, in the manufacturing process thereof. An object of the present invention is to realize a module for an optical device having a structure capable of effectively preventing damage to microlenses. Further, the present invention provides a method for manufacturing a small module for an optical device including a solid-state imaging device in which a microlens is formed on a photoelectric conversion element, and provides a manufacturing method with high yield that effectively prevents damage to the microlens. There is.

  In order to solve the above-described problem, an optical device module according to the present invention includes a solid-state imaging device having an effective pixel region having a microlens array, and a translucent coating that has translucency and covers the effective pixel region. The translucent covering material is fixed to an area outside the effective pixel area of the solid-state imaging device through a fixing portion, and the effective pixel area and the translucent covering material are separated from each other. It is characterized by being.

  According to the above configuration, the solid-state imaging device and the translucent covering material are fixed in a state where the effective pixel region and the translucent covering material are separated by the action of the fixing portion. For this reason, according to the said structure, the said translucent coating | covering material contacts the said micro lens array directly, and does not damage a micro lens array.

  In addition, according to the above configuration, one end of the fixed portion on the solid-state imaging device side is fixed to a region outside the effective pixel region, so that the effective pixel region and the fixed portion are in direct contact with each other thermally and mechanically. Never do. Therefore, even if the fixing portion is, for example, an adhesive, and the temperature of the fixing portion increases when the adhesive is solidified, thermal stress is not applied to the microlens array. In addition, even if mechanical force is applied to the solid-state image sensor from the outside while holding the translucent coating material, for example, for polishing the back surface of the solid-state image sensor, mechanical stress is applied to the microlens array. Never give.

  Therefore, according to the said structure, there exists an effect that the damage of the microlens array in the manufacturing process of the said module for optical devices can be prevented.

  The optical device module may further include one or more lenses arranged on the subject side of the translucent covering material.

  In the module for an optical device according to the present invention, the distance between the effective pixel region and the translucent covering material is preferably 10 μm or more.

  When dust adheres to a surface (hereinafter referred to as a lower surface) facing the effective pixel region of the translucent coating material, the dust creates a shadow on the effective pixel region, and is included in the shadow in the effective pixel region. The region becomes a defective pixel region. However, when the distance between the lower surface of the translucent covering material and the effective pixel region is increased, the range of the defective pixel region is widened, but the shadow is reduced, and the dust optically in the defective pixel region is reduced. The impact is reduced.

  According to the said structure, the distance from the said effective pixel area to the lower surface of the said translucent coating | covering material will be 10 micrometers or more. For this reason, even if dust adheres to the lower surface of the translucent covering material in the manufacturing process, the dust does not have an adverse effect on the optical characteristics of the effective pixel region.

  Further, according to the above configuration, the distance from the effective pixel region to the surface (hereinafter referred to as the upper surface) facing the lens of the translucent covering material is also greater than 10 μm. Therefore, even if dust adheres to the upper surface of the translucent coating material for the same reason as described above, the dust does not have an adverse effect on the optical characteristics of the effective pixel region.

  Therefore, according to the above configuration, it is possible to reduce the cost for dust management in the manufacturing environment of the optical device module or to reduce the defect occurrence rate due to dust, and to improve the yield of the optical device module. There is a further effect that it is possible.

  In the module for an optical device according to the present invention, the thickness of the translucent coating material is preferably 300 μm or more.

  When dust adheres to the surface of the translucent coating material facing the lens (hereinafter referred to as the upper surface), the dust creates a shadow on the effective pixel region, and the pixels included in the shadow in the effective pixel region are It becomes a defective pixel region. However, when the distance between the upper surface of the translucent covering material and the effective pixel region is increased, the range of the defective pixel region is widened, but the shadow is reduced, and the dust optically in the defective pixel region is reduced. The impact is reduced.

  According to the said structure, the distance from the said effective pixel area | region to the upper surface of the said translucent coating | covering material becomes larger than 300 micrometers. For this reason, even if dust adheres to the upper surface of the translucent covering material in the manufacturing process, the dust does not have an adverse effect on the optical characteristics of the effective pixel region.

  Therefore, according to the above configuration, it is possible to reduce the cost for dust management in the manufacturing environment of the optical device module and to reduce the defect occurrence rate due to dust, and to improve the yield of the optical device module. There is a further effect that it is possible.

  In the module for an optical device according to the present invention, the total distance between the effective pixel region and the translucent coating material, the thickness of the translucent coating material, and the thickness of the solid-state imaging element is 600 μm. The thickness is preferably 800 μm or less.

  When the distance between the effective pixel region and the translucent coating material, the thickness of the translucent coating material, and the total thickness of the solid-state imaging device are small, the translucent coating material, and the above Since the thickness of the solid-state imaging device cannot be secured sufficiently, the strength of the optical device module is reduced, and the possibility of breakage during process conveyance is increased. On the other hand, if the distance between the effective pixel region and the translucent coating material, the thickness of the translucent coating material, and the total thickness of the solid-state imaging device are large, the module for an optical device is Increase in size.

  Therefore, according to the said structure, there exists the further effect that the module for optical apparatuses which does not have trouble in process conveyance can be implement | achieved, without causing the enlargement of the module for optical apparatuses.

  In the module for an optical device according to the present invention, it is preferable that the fixing portion surrounds the effective pixel region and seals a space formed between the effective pixel region and the translucent covering material.

  According to the above configuration, the space formed between the effective pixel region and the translucent covering material is sealed by the fixing portion, so that foreign matters such as dust cannot enter the space from the outside. Absent. Therefore, it is possible to prevent a foreign pixel intruding from the outside from adhering to the microlens array and generating a defective pixel region.

  In the module for an optical device according to the present invention, it is preferable that the translucent coating material has a plate shape, and an optical filter is formed on the surface of the translucent coating material.

  According to the said structure, the said optical filter is formed in the surface of a plate-shaped translucent coating | covering material, without curving. Therefore, according to the said structure, there exists the further effect that the predetermined | prescribed filter performance defined at the time of design is realizable with respect to the incident light of arbitrary incident angles.

  In the module for an optical device according to the present invention, it is preferable that the fixing portion includes a photosensitive adhesive.

  According to the above configuration, since the fixing portion includes a photosensitive adhesive, the fixing portion can be formed with high accuracy and efficiency using a photolithography technique. .

  In the module for an optical device according to the present invention, the solid-state imaging device includes an electrode pad arranged in an area outside the effective pixel area and connected to an output terminal of the solid-state imaging element, and the electrode pad. A rewiring from the back surface to the electrode pad and connected to the electrode pad; and an external connection terminal disposed on the back surface of the surface on which the electrode pad is disposed and connected to the rewiring. The fixing part preferably embeds the electrode pad.

  According to the above configuration, the electrical signal output from the output terminal of the imaging device is transmitted to the external connection terminal disposed on the back surface of the solid-state imaging device via the electrode pad and the rewiring.

  And according to the said structure, the said electrode pad is fixed to a solid-state image sensor also by the effect | action of the said fixing | fixed part in addition to the coupling force to the solid-state image sensor itself. For this reason, according to the said structure, the coupling force of the said electrode pad to the said solid-state image sensor can be raised.

  In order to produce a module for an optical device having the above-described configuration, a through hole extending from the back surface of the solid-state image sensor to the electrode pad is formed in a state where the translucent covering material is fixed to the solid-state image sensor, A manufacturing method for forming a rewiring in the through hole can be employed. At this time, since the electrode pad is strongly coupled to the solid-state imaging device by the action of the fixing portion, according to the configuration, the electrode pad can be prevented from being detached from the solid-state imaging device when forming the rewiring. There is a further effect.

  In order to solve the above-described problems, a method for manufacturing a module for an optical device according to the present invention covers the semiconductor wafer on a semiconductor wafer in which a plurality of solid-state imaging devices each having an effective pixel region having a microlens array are arranged. A first step of fixing the translucent covering material, wherein in the first step, the translucent covering material is separated from the effective pixel region, and the outside of the effective pixel region in each of the solid-state imaging devices. It fixes to the area | region of this through a fixing | fixed part.

  In the first step, according to the configuration, the solid-state imaging device and the translucent covering material are separated from the effective pixel region and the translucent covering material by the action of the fixing portion. And are fixed. For this reason, according to the said structure, the said translucent coating | covering material and the said solid-state image sensor can be fixed, without damaging a micro lens array.

  In addition, according to the above configuration, one end of the fixed portion on the solid-state imaging device side is fixed to a region outside the effective pixel region, so that the effective pixel region and the fixed portion are in direct contact with each other thermally and mechanically. Never do. Therefore, even if the fixing portion is, for example, an adhesive, and the temperature of the fixing portion increases when the adhesive is solidified, thermal stress is not applied to the microlens array. In addition, even if mechanical force is applied to the solid-state image sensor from the outside while holding the translucent coating material, for example, for polishing the back surface of the solid-state image sensor, mechanical stress is applied to the microlens array. Never give.

  Therefore, according to the said structure, there exists an effect that the module for optical apparatuses can be manufactured, without damaging a micro lens array.

  The manufacturing method includes a plurality of lenses arranged on the surface of the translucent coating material opposite to the surface facing the semiconductor wafer, corresponding to the arrangement of the solid-state imaging elements on the semiconductor wafer. A second step of attaching the lens assembly plate may be included.

  In the method for manufacturing a module for an optical device according to the present invention, the distance between the effective pixel region and the translucent covering material is preferably 10 μm or more.

  When dust adheres to a surface (hereinafter referred to as a lower surface) facing the effective pixel region of the translucent coating material, the dust creates a shadow on the effective pixel region, and is included in the shadow in the effective pixel region. The region becomes a defective pixel region. However, although the distance between the lower surface of the translucent covering material and the effective pixel region and the range of the defective pixel region are widened, the shadow becomes thin and the optical influence of the dust in the defective pixel region is reduced. .

  According to the said structure, the distance from the said effective pixel area to the lower surface of the said translucent coating | covering material will be 10 micrometers or more. For this reason, even if dust adheres to the lower surface of the translucent covering material in the manufacturing process, the dust does not have an adverse effect on the optical characteristics of the effective pixel region.

  Further, according to the above configuration, the distance from the effective pixel region to the surface (hereinafter referred to as the upper surface) facing the lens of the translucent covering material is also greater than 10 μm. Therefore, even if dust adheres to the upper surface of the translucent coating material for the same reason as described above, the dust does not have an adverse effect on the optical characteristics of the effective pixel region.

  Therefore, according to the above configuration, it is possible to reduce the cost for dust management in the manufacturing environment, or to reduce the defect occurrence rate due to dust, and to improve the yield of the optical device module manufactured by the manufacturing method. There is a further effect that it is possible.

  In the method for manufacturing a module for an optical device according to the present invention, the thickness of the translucent coating material is preferably 300 μm or more.

  When dust adheres to the surface of the translucent coating material facing the lens (hereinafter referred to as the upper surface), the dust creates a shadow on the effective pixel region, and the pixels included in the shadow in the effective pixel region are It becomes a defective pixel region. However, when the distance between the upper surface of the translucent covering material and the effective pixel region is increased, the range of the defective pixel region is widened, but the shadow becomes thin, and the optical influence of the dust in the defective pixel region is reduced. Is reduced.

  According to the said structure, the distance from the said effective pixel area | region to the upper surface of the said translucent coating | covering material becomes larger than 300 micrometers. For this reason, even if dust adheres to the upper surface of the translucent covering material in the manufacturing process, the dust does not have an adverse effect on the optical characteristics of the effective pixel region.

  Therefore, according to the above-described configuration, it is possible to reduce the cost for dust management in the manufacturing environment and reduce the defect occurrence rate due to dust, and the yield of the optical device module can be improved. There is an effect.

  In the method for manufacturing a module for an optical device according to the present invention, the distance between the effective pixel region and the translucent coating material, the thickness of the translucent coating material, and the thickness of the solid-state imaging element are determined. The total is preferably 600 μm or more and 800 μm or less.

  According to the above configuration, the cost for dust management in the manufacturing process of the optical device module is reduced without causing an increase in the size of the optical device module, and the defect due to the dust attached to the translucent coating material It is possible to produce an optical device module that can reduce the occurrence rate and that does not interfere with process conveyance.

  In the method for manufacturing a module for an optical device according to the present invention, the fixed portion is formed so as to surround each effective pixel region, and is formed between each effective pixel region and the translucent covering material. It is preferable to seal the space.

  According to the above configuration, when the first step is completed, the space formed between the effective pixel region and the translucent covering material is sealed by the fixing portion. Therefore, it is possible to prevent foreign matters such as dust from entering the space after the first completion. Moreover, even when the structure produced | generated by the said 1st process is exposed to a chemical | medical solution after the said 1st process, such as an etching process by a chemical | medical solution, according to the said structure, the damage of the microlens by a chemical | medical solution There is a further effect that the translucent coating material can be prevented from being contaminated or contaminated by chemicals.

  In the method for manufacturing a module for an optical device according to the present invention, it is preferable that the translucent coating material is plate-shaped and an optical filter is formed on the surface of the translucent coating material.

  According to the said structure, the said optical filter is formed in the surface of a plate-shaped translucent coating | covering material, without curving. Therefore, according to the above configuration, the optical device module including the optical filter that realizes the predetermined filter performance determined at the time of design with respect to the incident light having an arbitrary incident angle can be manufactured. Play.

  In the method for manufacturing a module for an optical device according to the present invention, it is preferable that the fixing portion includes a photosensitive adhesive.

  According to the above configuration, since the fixing portion includes a photosensitive adhesive, the fixing portion is formed with high accuracy using a photolithography technique, and the solid-state imaging device and the translucent coating material are efficiently formed. There is an additional effect that it becomes possible to fix.

  In the method for manufacturing a module for an optical device according to the present invention, each solid-state image sensor included in the semiconductor wafer is arranged in an area outside the effective pixel area and is connected to an output terminal of the solid-state image sensor. Rewiring from the surface on the back side of the surface on which the electrode pad is disposed to the electrode pad and connected to the electrode pad; and on the surface on the back side of the surface on which the electrode pad is disposed. Preferably, in the first step, the electrode pad is formed on the solid-state imaging device, and then the fixing portion for embedding the electrode pad is formed in the first step.

  According to the above configuration, the electrode pad is fixed to the solid-state image sensor by the action of the fixing unit in addition to its own binding force to the solid-state image sensor. For this reason, according to the said structure, the coupling force of the said electrode pad to the said solid-state image sensor can be raised.

  After the first step, a manufacturing method in which a through hole from the back surface of the solid-state imaging device to the electrode pad is formed and rewiring is formed in the through hole can be employed. At this time, since the electrode pad is strongly coupled to the solid-state imaging device by the action of the fixing portion, according to the above configuration, the electrode pad can be prevented from being detached from the solid-state imaging device when the rewiring is formed. There is a further effect.

  In the method for manufacturing a module for an optical device according to the present invention, the size of the translucent covering material is preferably larger than the size of the semiconductor wafer.

  According to the said structure, it can prevent that a semiconductor wafer contacts an external obstruction and is damaged in a manufacturing process.

  As described above, the module for an optical device according to the present invention includes a solid-state imaging device having an effective pixel region having a microlens array, and a translucent covering material that has translucency and covers the effective pixel region. The translucent covering material is fixed to an area outside the effective pixel area of the solid-state imaging device through a fixing portion, and a space is formed between the effective pixel area and the translucent covering material. Has been.

  Therefore, at least the translucent coating material directly contacts the microlens array and does not damage the microlens array. Further, it is possible to prevent thermal stress or mechanical stress from being applied to the microlens array in the manufacturing process of the optical device module.

  In addition, as described above, the method for manufacturing a module for an optical device according to the present invention transparently covers the semiconductor wafer on a semiconductor wafer formed by arranging a plurality of solid-state imaging devices each having an effective pixel region having a microlens array. A first step of fixing the light-sensitive coating material, wherein in the first step, the light-transmitting coating material is separated from the effective pixel region, and the effective solid-state imaging device included in the semiconductor wafer includes the effective coating material. It fixes to the area | region outside a pixel area via a fixing | fixed part.

  Therefore, the solid-state image sensor and the solid-state image sensor can be fixed without damaging the microlens array. Further, it is possible to prevent thermal stress or mechanical stress from being applied to the microlens array in the step following the first step.

  An embodiment of the module for an optical device according to the present invention will be described below with reference to FIGS.

  FIG. 1 is a cross-sectional view of the optical device module 1 according to the present embodiment, and FIG. 2 is a top view of the optical device module 1. FIG. 3 is a perspective view of the optical device module 1. The cross-sectional view shown in FIG. 1 shows an X-X ′ cross section of the optical device module 1 as shown in FIGS. 2 and 3.

  As shown in FIG. 1, the optical device module 1 includes a solid-state imaging device 11, a translucent lid 12 (a translucent covering material), and a lens 13.

  As shown in FIG. 1, the solid-state imaging device 11 has a rectangular effective pixel region 11 a including a photoelectric conversion element in the vicinity of a central portion of a surface (hereinafter referred to as an upper surface) facing a translucent lid portion 12 described later. is doing. The effective pixel region 11a includes a plurality of photoelectric conversion elements such as photodiodes corresponding to a plurality of pixels, and outputs light received by each photoelectric conversion element into an electric signal. As shown in FIG. 1, the effective pixel region 11 a includes a microlens array 11 b that covers the surface of the effective pixel region 11 a and includes a plurality of microlenses arranged in an array. Thereby, the light incident on the effective pixel region 11a can be converted into electric power by the photoelectric conversion element with high light collection efficiency.

  The translucent lid portion 12 is a plate-like glass and covers the effective pixel region 11a as shown in FIG. The translucent lid 12 is bonded and fixed to the solid-state imaging device 11 via the bonding portion 14 (fixing portion) while being separated from the effective pixel region 11a. The translucent lid 12 is not limited to plate-like glass, and may be a translucent covering material, that is, a transparent member that has translucency and covers the effective pixel region. An air layer 15 is formed between the translucent lid 12 and the effective pixel region 11a.

  A photosensitive adhesive can be used as the bonding portion 14, and in this case, as will be described later, the bonding portion 14 can be formed by photolithography. The bonding portion 14 is formed on the outer peripheral region 11c that is outside the effective pixel region 11a and surrounds the effective pixel region 11a shown in FIG. 2, and between the translucent lid 12 and the effective pixel region 11a. The air layer 15 (space) in between is sealed.

  The lens 13 is configured to refract incident light so as to form an image of a subject on the effective pixel region 11a. As shown in FIG. 1, the lens 13 is supported by a lens frame 13a integrated with the lens 13, and the image forming distance of the lens 13 and the optical distance between the lens 13 and the effective pixel region 11a coincide with each other. Is retained. The light that has entered the lens 13 passes through the light-transmitting lid 12 and the air layer 15 and is condensed on the effective pixel region 11a of the solid-state imaging device 11, and the photoelectric conversion element formed on the effective pixel region 11a. Is converted into an electric signal.

  As shown in FIG. 1, the optical device module 1 further includes an electrode pad 16, a rewiring 17, and an external connection terminal 18.

  As shown in FIG. 1, the electrode pad 16 is disposed in the outer peripheral region 11 c of the solid-state image sensor 11 and is connected to an input / output circuit of the solid-state image sensor. In the solid-state imaging device 11, a rewiring 17 extending from the back surface of the solid-state imaging device 11 to the electrode pad 16 is formed. Further, an external connection terminal 18 is formed on a portion of the rewiring 17 exposed on the back surface of the solid-state imaging device 11. Thereby, the electric signal generated by the photoelectric conversion element in the effective pixel region 11 a can be taken out from the external connection terminal 18 provided on the back surface of the solid-state imaging element 11.

  Further, the electrode pad 16 is embedded in the bonding portion 14 described above. Thereby, it is possible to prevent the electrode pad 16 from being detached from the solid-state imaging device 11 when rewiring is formed from the back surface of the solid-state imaging device 11. A method for forming the rewiring 17 will be described later.

  As shown in FIG. 1, the optical device module 1 further includes an optical filter 19. The optical filter 19 is a filter that blocks incident light in a specific wavelength region, for example, an infrared cut filter that blocks infrared rays.

  As shown in FIG. 1, the optical filter 19 is formed on a translucent lid portion 12 formed in a plate shape. Therefore, unlike the case where the optical filter 19 is attached to the lens 13 having a curved surface, the optical filter 19 receives incident light of a specific wavelength with predetermined performance determined at the time of design with respect to incident light incident from an arbitrary direction. Can be blocked.

  As shown in FIG. 1, in the optical device module 1, the optical filter 19 is attached to the upper surface of the translucent lid portion 12, that is, the surface facing the lens 13. It is not limited. That is, the optical filter 19 may be attached to the lower surface of the translucent lid 12, that is, the surface facing the effective pixel region 11a. When the optical filter 19 is attached to the lower surface of the translucent lid 12, damage to the optical filter 19 and adhesion of dust can be effectively prevented in the manufacturing process described later.

  Further, instead of the optical filter 19, a diaphragm member having a window portion at the center may be provided on the upper surface or the lower surface of the translucent lid portion 12. The optical filter 19 and the diaphragm member may be provided at the same time.

  Next, the solid-state imaging device 11, the translucent lid 12, and the distance between the translucent lid 12 and the effective pixel region 11 a, that is, the thickness of the air layer 15 in the optical device module 1 will be further described. To do. In the following description, as shown in FIG. 1, the thickness of the solid-state imaging device 11 is h3, and the thickness of the translucent lid 12 is h2. The thickness of the air layer 15 is h1.

  First, the influence of dust attached to the translucent lid 12 on the optical characteristics of the effective pixel region 11a will be described.

  When dust adheres to a surface (hereinafter referred to as a lower surface) facing the effective pixel region 11a of the translucent lid 12 or a surface (hereinafter referred to as an upper surface) facing the lens 13, the dust is placed on the effective pixel region 11a. A shadow is created, and the area included in the shadow in the effective pixel area 11a becomes a defective pixel area having a poor light receiving state.

  However, when the distance between the upper surface or the lower surface of the translucent lid 12 and the effective pixel region 11a is increased, the range of the defective pixel region is widened, but the shadow becomes thin, and the optical dust of the defective pixel region is reduced. The impact is reduced. Accordingly, by setting these distances to be larger, the optical device module 1 that does not effectively affect the light receiving state of the effective pixel region 11a even when dust adheres to the translucent lid portion 12 can be realized. .

  In order to prevent the dust adhering to the lower surface of the translucent lid 12 from having an effective influence on the light receiving state of the effective pixel region 11a, there is a gap between the lower surface of the translucent lid 12 and the effective pixel region 11a. The distance h1 is preferably 10 μm or more. Furthermore, if the distance h1 between the lower surface of the translucent lid 12 and the effective pixel region 11a is 20 μm or more, dust attached to the lower surface of the translucent lid 12 gives the light receiving state of the effective pixel region 11a. The impact can be further reduced.

  Moreover, it is preferable that the thickness h2 of the translucent cover part 12 is 300 micrometers or more. At this time, since the distance between the upper surface of the translucent lid 12 and the effective pixel region 11a is at least 300 μm or more, the dust adhering to the upper surface of the translucent lid 12 is in the light receiving state of the effective pixel region 11a. Can be prevented from having an effective effect. Furthermore, if the thickness h2 of the translucent lid 12 is 400 μm or more, the influence of dust attached to the upper surface of the translucent lid 12 on the light receiving state of the effective pixel region 11a can be further reduced.

  The total h1 + h2 + h3 of the thickness h1 of the air layer 15, the thickness h2 of the translucent lid 12, and the thickness h3 of the solid-state imaging device 11 is preferably 600 μm or more and 800 μm or less. By setting the total thickness to 600 μm or more and 800 μm or less, it is possible to prevent the optical device module 1 from being damaged at the time of process transfer without causing an increase in the size of the optical device module 1. In particular, the total thickness is preferably 700 μm to 800 μm for a 12 inch wafer, the total thickness is 650 μm to 750 μm for an 8 inch wafer, and the total thickness is 600 μm to 700 μm for a 6 inch wafer.

  Next, an outline of a method for manufacturing the optical device module 1 according to the present embodiment will be described with reference to FIG. FIG. 4 is an explanatory diagram showing an outline of a method for manufacturing the optical device module 1 according to the present embodiment.

  As shown in FIG. 4, in the manufacturing method, first, the semiconductor wafer 21 and the translucent plate material 22 (translucent coating material) are fixed.

  Here, the semiconductor wafer 21 is an aggregate of solid-state image sensors in which a plurality of solid-state image sensors are arranged in an array. Since each individual image pickup device in the semiconductor wafer 21 has the same configuration as that of the solid-state image pickup device 11 described above, the description thereof is omitted here, and the constituent members of each individual image pickup device are the member numbers of the constituent members of the solid-state image pickup device 11. The same part number is referred to. Further, in the semiconductor wafer 21, the electrode pad 16 is formed in advance on the surface where the effective pixel region 11 a of each individual image sensor 1 is formed, and the electrode pad 16 and the output terminal of the solid-state image sensor 11 are electrically connected. Keep it.

  The translucent plate material 22 is glass formed in a plate shape, and the one obtained by dividing the glass into the size of the solid-state imaging device 1 corresponds to the translucent lid portion 12. The translucent plate 22 is not limited to a plate-like glass, and any transparent member that covers the semiconductor wafer 21 is sufficient.

  As shown in FIG. 4, in the manufacturing method according to the present embodiment, first, a photosensitive adhesive 23 (fixed portion) patterned on a semiconductor wafer 21 in a lattice shape as will be described later. ) Through (step 1). The patterning process of the photosensitive adhesive 23 and the process of solidifying the photosensitive adhesive 23 and bonding and fixing the semiconductor wafer 21 and the translucent plate 22 are performed by coating, exposing, developing, and the like well-known as a photolithography technique. Each process can be performed. Thereby, the position of the fixing part and the height of the fixing part (that is, the distance between the translucent lid 12 and the effective pixel region 11a) in the optical device module 1 can be adjusted with high accuracy.

  The transparent plate 22 fixed to the thin semiconductor wafer 21 functions as a wafer support in the manufacturing process of the optical device module. As a result, the semiconductor wafer 21 can be transported without being damaged, and the back surface of the semiconductor wafer 21 described later can be polished. Further, the size of the translucent plate 22 is preferably set larger than the size of the semiconductor wafer 21, for example, 0.1 to 2 mm larger than the size of the semiconductor wafer 21. Thereby, it is possible to prevent the semiconductor wafer 21 from coming into contact with an external obstacle and being damaged in the manufacturing process, particularly in the manufacturing process after the process of polishing the back surface of the semiconductor wafer 21 described later.

  Here, the patterning of the photosensitive adhesive 23 will be described. The photosensitive adhesive 23 may be applied to the light transmissive plate 22 side or may be applied to the semiconductor wafer 21 side. Therefore, the case where the photosensitive adhesive 23 is applied to the translucent plate 22 will be described with reference to FIG. 5, and the case where the photosensitive adhesive 23 is applied to the semiconductor wafer 21 will be described with reference to FIG. While explaining.

  FIG. 5 is a diagram for explaining the patterning of the photosensitive adhesive 23 when the photosensitive adhesive 23 is applied to the translucent plate 22. Here, FIG. 5A is a top view of the translucent plate 22 and the semiconductor wafer 21, FIG. 5B is a cross-sectional view of the translucent plate 22 and the semiconductor wafer 21 in the YY ′ section, and FIG. c) is a cross-sectional view in the YY ′ cross section of the translucent plate 22 and the semiconductor wafer 21 for showing another patterning of the photosensitive adhesive 23.

  As shown in FIG. 5B, the photosensitive adhesive 23 is applied to the grid-like region including the scrub line corresponding to the boundary 21 a of the solid-state imaging device on the semiconductor wafer 21. It coat | covers so that it may not contact the area | region 11a. Further, as shown in FIG. 5C, the photosensitive adhesive 23 may be applied to a region excluding the scrub line from the lattice region.

  When the photosensitive adhesive 23 is applied to the grid area shown in FIG. 5B, there is an advantage that the degree of sealing of the air layer 15 from the external environment is improved as the adhesion area is increased. On the other hand, when the photosensitive adhesive 23 is applied to the region shown in FIG. 5C, there is a merit that voids (gap) that may be generated at the step of the adhesion region can be suppressed.

  As shown in FIGS. 5B and 5C, when the adhesive pattern is formed on the translucent plate 22, the development is caused by the flatness of the surface on which the adhesive pattern is formed. There is an advantage that residue removal becomes easy.

  FIG. 6 is a diagram for explaining patterning of the photosensitive adhesive 23 when the photosensitive adhesive 23 is applied to the semiconductor wafer 21. 6A is a top view of the translucent plate 22 and the semiconductor wafer 21, FIG. 6B is a cross-sectional view of the translucent plate 22 and the semiconductor wafer 21 in the YY ′ section, and FIG. c) is a cross-sectional view of the translucent plate 22 and the semiconductor wafer 21 taken along the line YY ′, showing another patterning of the photosensitive adhesive 23.

  As shown in FIG. 6B, the photosensitive adhesive 23 is applied to the grid-like region including the boundary 21a of the solid-state imaging device in the semiconductor wafer 21 so as not to contact each effective pixel region 11a. Further, as shown in FIG. 6C, the photosensitive adhesive 23 may be applied to a region excluding the scrub line from the lattice region.

  When the photosensitive adhesive 23 is applied to the lattice region shown in FIG. 6B, there is a merit that the degree of sealing of the air layer 15 from the external environment is improved as the bonding area is increased. On the other hand, when the photosensitive adhesive 23 is applied to the region shown in FIG. 6C, there is a merit that voids (gap) that may be generated at the step of the adhesion region can be suppressed.

  In the case where an adhesive pattern is formed on the semiconductor wafer 21 as shown in FIG. 6B and FIG. 6C, it is easy to align the semiconductor wafer 21 and the translucent plate 22. There is a merit that

  Whether the patterning shown in FIG. 5 or the patterning shown in FIG. 6 is adopted, the electrode pad 16 is embedded in the photosensitive adhesive 23. Therefore, when the photosensitive adhesive 23 is solidified or annealed, even if the fixing portion made of the photosensitive adhesive 23 is slightly deformed, the sealing of the air layer 15 by the photosensitive adhesive 23 is broken. It can be effectively prevented.

  The thickness of the photosensitive adhesive 23 is preferably set to have a thickness of 10 μm or more after solidification, and more preferably set to have a thickness of 20 μm or more after solidification. By setting the thickness of the photosensitive adhesive in this manner, the optical device module 1 that does not effectively affect the light receiving state of the effective pixel region 11a even when dust adheres to the translucent plate 22 is manufactured. It becomes possible to do.

  Note that the pattern of the photosensitive adhesive 23 is not limited to that described above, and at least the area outside the effective pixel area 11a of each individual imaging element 11 included in the semiconductor wafer 21 and the above-described translucent plate 22 are photosensitively bonded. What is necessary is just to be fixed through the agent 23.

  Moreover, it is preferable that the photosensitive adhesive 23 is further provided with flame retardancy. By manufacturing the optical device module 1 using a photosensitive adhesive having flame retardancy as the photosensitive adhesive 23, for example, V-0 can be confirmed by a flame retardancy test in accordance with UL-94. An optical device module 1 that passes the flammability test can be provided. Such an optical device module 1 can also be suitably used for an optical device that is supposed to be used in a high temperature environment.

  In the present embodiment, the photosensitive adhesive 23 is used as a fixing portion for fixing the semiconductor wafer 21 and the translucent plate 22. However, the present invention is not limited to this. That is, for example, it is also possible to pattern the sheet-like photosensitive film by photolithography and fix the semiconductor wafer 21 and the translucent plate material 22 using this as a fixing portion. It is also possible to print and form the fixed part using a print mask.

  As shown in FIG. 4, the back surface of the semiconductor wafer 21 is polished following the above process. The backside polishing of the semiconductor wafer 21 is a process for thinning the semiconductor wafer 21 to a thickness of several tens of μm to several hundreds of μm. Specifically, the back surface of the semiconductor wafer 21 is polished using, for example, a back grinder, using the translucent plate 22 as a wafer support. The thickness of the semiconductor wafer 21 after polishing is such that the through-holes extending from the back surface of the semiconductor wafer 21 to the electrode pads 16 can be formed in a practical time without technical trouble by deep etching. good.

  At the time of polishing by the back grinder described above, mechanical stress is applied between the semiconductor wafer 21 and the translucent plate 22 that is the wafer support. However, since the semiconductor wafer 21 and the translucent plate material 22 are fixed via the photosensitive adhesive 23 in a region outside the effective pixel region 11a, this mechanical stress is applied to the microlens on the effective pixel region 11a. There is no effect on the array 11b. Therefore, the microlens array 11b is not damaged in this process.

  Subsequently, as shown in FIG. 4, a process of forming the rewiring 17 and the external connection terminal 18 is performed. A process of forming the rewiring 17 and the external connection terminal 18 will be described with reference to FIG. Here, FIG. 7A is a top view of a structure including the semiconductor wafer 21 and the translucent plate 22, and FIGS. 7B to 7D show YY ′ of the structure. FIG. 7E is a bottom view showing a state of the lower surface of the structure after the external connection terminals 18 are formed.

  As shown in FIG. 7C, through holes 17a extending from the back surface of the semiconductor wafer 21 to the electrode pads 16 are formed by deep etching. The through-hole may be formed by reactive ion etching that is generally performed. In order to insulate the semiconductor wafer 21 and the rewiring 17 from each other, an insulating film is formed on the inner wall of the through hole 17a after the through hole 17a is formed. The insulating film may be formed by plasma CVD, for example. Subsequently, a conductive layer composed of a barrier layer such as TaN, a Cu seed layer, and Cu plating is formed, and then a rewiring 17 is formed on the through hole 17a and the back surface of the wafer by photolithography and etching. Thereafter, a protective film is formed on the back side of the semiconductor wafer 21, and an external connection terminal 18 is formed in a part where a part of the protective film is opened and the rewiring 17 is exposed so as to be electrically connected to the part. Here, the electrode pad 16 presses the rewiring 17 from the front surface side of the semiconductor wafer 21, thereby preventing the rewiring 17 from being exposed to the front surface side of the semiconductor wafer 21. Here, since the electrode pad 16 is embedded in the light-transmitting adhesive 23 solidified as described above, the electrode pad 16 is not detached from the surface of the semiconductor wafer 21.

  In the above-described steps, the external connection terminals 18 are arranged in the periphery of the back surface of each solid-state image sensor 1 included in the semiconductor wafer 21. In addition to these external connection terminals 18, the center of the back surface of each individual image sensor 1 is further provided. The external connection terminal 18a may be arranged in the part. The external connection terminals 18a arranged in the central part may be electrically connected to the output or input terminal of the solid-state imaging device 1 in the same manner as the external connection terminals 18 arranged in the peripheral part. Alternatively, it may be a dummy terminal. 7D is a cross-sectional view of the semiconductor wafer 21 in the state where the external connection terminals are formed on the entire back surface of each individual image pickup device 1 included in the semiconductor wafer 21, and FIG. e). As shown in FIG. 7E, the external connection terminals 18 and 18a are arranged in a well-balanced manner on the entire back surface of the solid-state imaging device 1, so that the optical device module 1 is mounted when the optical device module 1 is mounted on the optical device. It is possible to effectively disperse the thermal stress or the mechanical stress applied to 1 and prevent the optical device module 1 from being damaged.

  Subsequently, as shown in FIG. 4, a step (second step) of further fixing the lens assembly plate 24 to the structure composed of the semiconductor wafer 21 and the translucent plate 22 is performed. The lens assembly plate 24 is composed of a plurality of lenses arranged corresponding to the arrangement of the solid-state imaging elements on the semiconductor wafer 21. Here, each lens included in the lens assembly plate 24 has the same structure as the lens 13 described above. The lens assembly plate 24 is aligned so that the center of each lens included in the lens assembly plate 24 and the center of the effective pixel region 11a of each solid-state imaging device 1 included in the semiconductor wafer 21 coincide with each other. The adhesive plate material 22 is bonded and fixed. FIG. 8 shows a structure 25 composed of a semiconductor wafer 21, a translucent plate member 22, and a lens assembly plate 24 obtained by completing the process of fixing the lens assembly plate 24. Here, FIG. 8A is a top view of the structure 25, and FIG. 8B is a cross-sectional view showing a Y-Y ′ section of the structure.

  Finally, as shown in FIG. 4, after the above steps are completed, the structure 25 including the semiconductor wafer 21, the translucent plate material 22, and the lens assembly plate 24 is formed using, for example, a dicing saw 26. By dividing and dividing into individual pieces, the individual optical device modules 1 described above are formed.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. That is, embodiments obtained by combining technical means appropriately changed within the scope of the claims are also included in the technical scope of the present invention.

  The module for an optical device according to the present invention can be used as an image pickup unit mounted on the optical device, and is particularly suitable for mounting on a small optical device such as a mobile phone with a camera.

It is sectional drawing which shows the structure of the module for optical devices which concerns on embodiment of this invention. It is a top view which shows the structure of the module for optical devices which concerns on embodiment of this invention. It is a perspective view which shows the structure of the module for optical devices which concerns on embodiment of this invention from the external appearance. It is explanatory drawing explaining the outline of the manufacturing method of the module for optical devices which concerns on embodiment of this invention. FIG. 5A shows a pattern of a photosensitive adhesive in a method for manufacturing a module for an optical device according to an embodiment of the present invention. FIG. 5A is a top view of a translucent plate material and a semiconductor wafer, and FIG. FIG. 3 is a cross-sectional view of a translucent plate material and a semiconductor wafer. FIG. 5C shows another pattern of the photosensitive adhesive, and is a cross-sectional view of a translucent plate material and a semiconductor wafer. The pattern of the photosensitive adhesive in the manufacturing method of the module for optical devices which concerns on embodiment of this invention is shown, Fig.6 (a) is a top view of a translucent board | plate material and a semiconductor wafer, FIG.6 (b). FIG. 3 is a cross-sectional view of a translucent plate material and a semiconductor wafer. FIG. 6C shows another pattern of the photosensitive adhesive, and is a cross-sectional view of a translucent plate material and a semiconductor wafer. FIG. 7A shows a process of forming rewiring and external connection terminals in the method for manufacturing an optical device module according to the embodiment of the present invention, and FIG. 7A is a top view of a light-transmitting plate material and a semiconductor wafer; 7B to 7D are cross-sectional views of the translucent plate material and the semiconductor wafer, and FIG. 7E is a bottom view of the translucent plate material and the semiconductor wafer. FIG. 8A shows the structure of a structure including a translucent plate, a semiconductor wafer, and a lens assembly plate in a method for manufacturing an optical device module according to an embodiment of the present invention. FIG. A top view and FIG. 8B are cross-sectional views of the structure. It is sectional drawing which shows the structure of the camera module which is the module for conventional optical apparatuses.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical device module 11 Solid-state image sensor 11a Effective pixel area 11b Microlens array 11c Outer peripheral area 12 Translucent cover (translucent covering material)
13 Lens 13a Lens frame 14 Bonding part (fixing part)
15 Air layer (space)
16 Electrode pad 17 Rewiring 17a Through hole 18 External connection terminal 19 Optical filter 21 Semiconductor wafer 22 Translucent plate material (translucent coating material)
23 Photosensitive adhesive (fixing part)
24 Lens assembly plate

Claims (16)

A solid-state imaging device having an effective pixel region with a microlens array;
A translucent covering material that has translucency and covers the effective pixel region,
The translucent covering material is fixed to an area outside the effective pixel area in the solid-state imaging device through a fixing portion, and the effective pixel area and the translucent covering material are separated from each other. Module for optical device.   2. The optical device module according to claim 1, wherein a distance between the effective pixel region and the translucent covering material is 10 μm or more.   The optical device module according to claim 1, wherein the translucent covering material has a thickness of 300 μm or more.   The distance between the effective pixel region and the translucent covering material, the thickness of the translucent covering material, and the total thickness of the solid-state imaging element is 600 μm or more and 800 μm or less. Item 4. The optical device module according to Item 2 or 3.   2. The optical device module according to claim 1, wherein the fixing unit surrounds the effective pixel region and seals a space formed between the effective pixel region and the translucent covering material. The translucent coating material is plate-shaped,
The optical device module according to claim 1, wherein an optical filter is formed on a surface of the translucent covering material.   The optical device module according to claim 1, wherein the fixing portion includes a photosensitive adhesive. The solid-state imaging device is arranged in an area outside the effective pixel area and connected to an output or input terminal of the solid-state imaging device, and the electrode pad from the back surface of the surface on which the electrode pad is arranged A rewiring connected to the electrode pad and an external connection terminal connected to the rewiring disposed on the back surface of the surface on which the electrode pad is disposed,
The optical device module according to claim 1, wherein the fixing portion has the electrode pad embedded therein. Including a first step of fixing a translucent covering material covering the semiconductor wafer to a semiconductor wafer formed by arranging a plurality of solid-state imaging devices each having an effective pixel area including a microlens array;
In the first step, the translucent covering material is fixed to a region outside the effective pixel region in each solid-state imaging device included in the semiconductor wafer via a fixing unit, separated from the effective pixel region. A method for manufacturing a module for an optical device.   The method for manufacturing a module for an optical device according to claim 9, wherein a distance between the effective pixel region and the translucent covering material is 10 μm or more.   The method for manufacturing a module for an optical device according to claim 9, wherein the translucent covering material has a thickness of 300 μm or more.   The distance between the effective pixel region and the translucent covering material, the thickness of the translucent covering material, and the total thickness of the solid-state imaging element is 600 μm or more and 800 μm or less. Item 12. The optical device module according to Item 10 or 11.   The said fixing | fixed part is formed so that each said effective pixel area may be enclosed, and the space formed between each said effective pixel area and the said translucent coating | covering material is sealed. Manufacturing method of module for optical device.   The method for manufacturing a module for an optical device according to claim 9, wherein the fixing portion includes a photosensitive adhesive. Each solid-state imaging device included in the semiconductor wafer is disposed outside the effective pixel region and is connected to an output or input terminal of the solid-state imaging device, and the back side of the surface on which the electrode pad is disposed. A rewiring from the surface to the electrode pad and connected to the electrode pad, and an external connection terminal disposed on the back side of the surface on which the electrode pad is disposed and connected to the rewiring,
10. The method for manufacturing a module for an optical device according to claim 9, wherein, in the first step, after the electrode pad is formed on the solid-state imaging device, the fixing portion for embedding the electrode pad is formed. .   The method of manufacturing a module for an optical device according to claim 9, wherein a size of the translucent coating material is larger than a size of the semiconductor wafer.

Images