JP6499042B2 - Imaging device mounting substrate and imaging apparatus - Google Patents

Description

The present invention is, for example, a CCD (Charge Coupled Device) type or CMOS (Complementary).
The present invention relates to an imaging device mounting substrate and an imaging device on which an imaging device such as a metal oxide semiconductor) type is mounted.

  Conventionally, a technique for joining a substrate and a flexible substrate is known. An electrode formed on the upper surface of the substrate is connected to the lower surface of the flexible substrate, and a protective material made of resin or the like is covered on the exposed electrode on the upper surface of the substrate to protect the electrode.

JP 2000-294891 A

  However, in the prior art, it is necessary to add a heating process for curing the protective material made of resin or the like. In general, the substrate and the flexible wiring substrate have different coefficients of thermal expansion. From these facts, by adding a heating process for curing the protective material, the heat load is greatly applied to the joining portion, and there has been a concern about peeling or deformation of the members. In particular, it has become difficult to secure a bonding area in an image sensor mounting substrate and an image pickup apparatus on which an image sensor that is required to be downsized in recent years is mounted, and it is necessary to suppress peeling of the flexible substrate. It is coming.

  An object of the present invention is to use an image pickup device mounting substrate and an image pickup device mounting substrate that can suppress peeling between the frame body and the flexible substrate or between the flexible substrate and the flat plate, or deformation thereof. It is to provide an image pickup apparatus.

  An image pickup device mounting substrate according to one aspect of the present invention is connected to a flat plate having an image pickup device mounting portion in a central region of an upper surface and a peripheral region on the flat plate surrounding the central region, and a part thereof A flexible substrate extending outward and having a conductive layer inside, a cutout portion in which the central region side is cut out on the upper surface and the conductive layer is located; and on the cutout portion of the flexible substrate A frame body that surrounds the imaging element mounting portion and is provided continuously along the peripheral region, and the frame body and the flexible substrate are connected via an anisotropic conductive film, and the anisotropic The conductive film covers the entire surface of the conductive layer located at the notch.

An imaging device mounting substrate according to one aspect of the present invention is connected to a flat plate having an imaging device mounting portion in a central region of an upper surface, and a peripheral region on the flat plate surrounding the central region, and a part thereof A plurality of conductive layers inside and a first cutout portion in which the central region side is cut out on the upper surface and the uppermost conductive layer is located among the plurality of conductive layers; A flexible board having a second cutout portion on the lower surface, the second cutout portion being cut out on the side of the central region and in which the lowermost conductive layer of the plurality of conductive layers is located, and the first cutout portion of the flexible board from above A frame body continuously surrounding the peripheral region and surrounding the imaging element mounting portion, the frame body and the flexible substrate being connected via a first anisotropic conductive film, The anisotropic conductive film is located in the first notch Covering the entire surface of the uppermost conductive layer, the flexible substrate and the flat plate are connected via a second anisotropic conductive film, and the second anisotropic conductive film is connected to the second notch. The entire surface of the lowermost conductive layer located is covered.

An imaging device according to an aspect of the present invention includes the imaging device mounting substrate according to any one of the above, and an imaging device mounted on an upper surface of the imaging device mounting substrate, wherein the imaging device is the imaging device. It is mounted at a position that overlaps the mounting part.

An imaging device mounting substrate according to one aspect of the present invention is connected to a flat plate having an imaging device mounting portion in a central region of an upper surface, and a peripheral region on the flat plate surrounding the central region, and a part thereof A flexible substrate extending outward and having a conductive layer inside, a cutout portion in which the central region side is cut out on the upper surface and the conductive layer is located; and on the cutout portion of the flexible substrate The frame body and the flexible substrate are connected to each other through an anisotropic conductive film, and are provided continuously along the peripheral region. The isotropic conductive film covers the entire surface of the conductive layer located at the notch.

  Accordingly, it is possible to provide an imaging element mounting substrate that can reduce peeling between the frame body and the flexible substrate or between the flexible substrate and the flat plate, or deformation thereof.

In addition, an imaging element mounting substrate according to one aspect of the present invention is connected to a flat plate having an imaging element mounting portion in a central region of an upper surface and a peripheral region on the flat plate surrounding the central region. A first cutout portion having a plurality of conductive layers inside and a top surface of the plurality of conductive layers, wherein the uppermost conductive layer is located. And a flexible printed circuit board having a second notch on the lower surface, the second notch being located on the lower side of the plurality of conductive layers, and a first notch on the flexible board. A frame body that is provided continuously along the peripheral region and surrounds the imaging element mounting portion, and the frame body and the flexible substrate are connected via a first anisotropic conductive film, The first anisotropic conductive film has the first notch. Covering the entire surface of the uppermost conductive layer located in the section, the flexible substrate and the flat plate are connected via a second anisotropic conductive film, and the second anisotropic conductive film is connected to the second cut All the surfaces of the lowermost conductive layer located in the notch are covered.

  Accordingly, it is possible to provide an image sensor mounting substrate that can reduce peeling between the frame and the flexible substrate or between the flexible substrate and the flat plate, or deformation thereof.

(A) is a top view which shows the external appearance of the image pick-up element mounting board | substrate and imaging device which concern on the 1st Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the AA line of (a). is there. (A) is a top view which shows the external appearance of the image pick-up element mounting board | substrate and imaging device which concern on the 2nd Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the AA line of (a). is there. (A) is a top view which shows the external appearance of the image pick-up element mounting board | substrate and imaging device which concern on the 3rd Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the AA line of (a). is there. (A) is a top view which shows the external appearance of the image pick-up element mounting board | substrate and imaging device which concern on the 4th Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the AA line of (a). is there. (A) is a top view which shows the external appearance of the image pick-up element mounting board | substrate and imaging device which concern on the 5th Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the AA line of (a). is there.

Hereinafter, some exemplary embodiments of the present invention will be described with reference to the drawings. In addition,
In the following description, a configuration in which an imaging element is mounted on an imaging element mounting substrate and a lid is bonded to the upper surface of the imaging element mounting substrate is referred to as an imaging device. The imaging element mounting substrate and the imaging device may be either upward or downward. For convenience, the orthogonal coordinate system xyz is defined and the positive side in the z direction is upward.

(First embodiment)
With reference to FIG. 1, the imaging device 21 and the imaging element mounting substrate 1 according to the first embodiment of the present invention will be described. The imaging device 21 in this embodiment includes an imaging element mounting substrate 1 and an imaging element 10.

  The imaging element mounting substrate 1 includes a flat plate 4, a flexible substrate 5, and a frame 2. The flat plate 4 has an image sensor mounting portion 11 in the central region of the upper surface. The flexible substrate 5 is connected to a peripheral region on the flat plate 4 and surrounding the central region, and a part of the flexible substrate 5 extends outward, and the conductive layer 7 is formed inside, and the central region side is cut out on the upper surface. It has a notch 6 in which the conductive layer 7 is located. The frame body 2 is provided continuously along the peripheral region from above the cutout portion 6 of the flexible substrate 5 and surrounds the imaging element mounting portion 11. The frame 2 and the flexible substrate 5 are connected via an anisotropic conductive film 23, and the anisotropic conductive film 23 covers the entire surface of the conductive layer 7 located in the notch 6.

  The image pickup device mounting substrate 1 has a flat plate 4 having an image pickup device mounting portion 11 in the central region of the upper surface. The flat plate 4 has an image sensor mounting portion 11 in the central region of the upper surface.

  For example, a material having high thermal conductivity is used as the material constituting the flat plate 4. Examples of the material for forming the flat plate 4 include an aluminum nitride sintered body, a silicon nitride sintered body, or silicon (Si). When the material for forming the flat plate 4 is, for example, an aluminum nitride crystal or a silicon nitride chamber crystal, the flat plate 4 may be a laminate composed of a plurality of insulating layers.

Moreover, a metal material is also used as the material of the flat plate 4, and examples of the metal material include stainless steel (SUS), Fe—Ni—Co alloy, 42 alloy, copper (Cu), Kovar, or copper alloy. For example, when the frame 2 is an aluminum oxide sintered body having a thermal expansion coefficient of about 5 × 10 ⁻⁶ / ° C. to 10 × 10 ⁻⁶ / ° C., the flat plate 4 is about 10 × 10 ⁻⁶ / ° C. Stainless steel (SUS410) having a coefficient of thermal expansion can be used. In this case, since the thermal contraction difference and the thermal expansion difference between the frame 2 and the flat plate 4 are reduced, the deformation of the image sensor mounting portion 11 can be reduced. As a result, the optical axis shift between the image sensor 10 and the lens can be suppressed, and the sharpness of the image can be maintained satisfactorily. Further, when the flat plate 4 is made of a metal material, it is possible to reduce the obstruction of the flat plate 4 from the function of an external device such as a lens drive because the material is a non-magnetic material.

  The imaging device mounting substrate 1 is connected to a peripheral region on the flat plate 4 and surrounding the central region, and part of the substrate 1 extends outward, and the conductive layer 7 is formed inside, and the central region side is disposed on the upper surface. It has a flexible substrate 5 that has a notch 6 that is notched and in which the conductive layer 7 is located. In FIG. 1, the notch 6 exists only at one location of the flexible substrate 5, but may be provided on all four sides surrounding the peripheral region, for example.

The flexible substrate 5 has a base film 5b.
As a material for forming the base film 5b, an insulator made of a resin such as a polyimide film is used.

The flexible substrate 5 has a conductive layer 7 on the upper surface of the base film 5b. Conductive layer 7
Is made of copper, aluminum, gold, nickel or an alloy containing at least one metal material selected from these.

  In addition, a plating layer may be provided on the exposed surface of the conductive layer 7. According to this configuration, the exposed surface of the conductive layer 7 can be protected and oxidation can be suppressed. Moreover, according to this structure, the electrical connection of the electrical connection through the anisotropic conductive film 23 of the frame 2 mentioned later and the conductive layer 7 can be made favorable. As the plating layer, for example, a Ni plating layer having a thickness of 0.5 to 10 μm may be deposited, or even if this Ni plating layer and a gold (Au) plating layer having a thickness of 0.5 to 3 μm are sequentially deposited. Good. Furthermore, Sn plating may be performed on the plating layer.

  The flexible substrate 5 has a cover film 5 c provided on the upper surface of the conductive layer 7. The cover film 5 c is a film for protecting the surface of the conductive layer 7, and is provided on the surface of the conductive layer 7 by applying an adhesive to one side of a film made of a resin material such as a polyimide film.

  The bonding material for bonding the flexible substrate 5 and the flat plate 4 is made of a material that is not easily denatured by heat applied in the mounting process of the image sensor 10. Such a bonding material is bisphenol A type liquid epoxy resin or polyimide resin. In this case, peeling of the flexible substrate 5 and the flat plate 4 in the mounting process of the image sensor 10 can be satisfactorily suppressed.

  The image pickup device mounting substrate 1 includes an image pickup device mounting portion 11 provided continuously along the peripheral region from the cutout portion 6 of the flexible substrate 5 to the upper surface of the flexible substrate 5 excluding the cutout portion 6. It has a surrounding frame 2.

  The frame 2 is made of an insulating layer and has a first through hole 2a. An image sensor connection pad 3 is provided on the upper surface of the frame 2 made of an insulating layer. Although not shown, a plurality of external circuit connection electrodes connected to the flexible substrate 5 may be provided on the lower surface of the frame 2. As the material of the insulating layer constituting the frame body 2, for example, electrically insulating ceramics or resin (plastics) is used.

  Examples of the electrically insulating ceramic used as the material of the insulating layer forming the frame 2 include, for example, an aluminum oxide sintered body, a mullite sintered body, a silicon carbide sintered body, an aluminum nitride sintered body, and a nitrided body. Examples thereof include a silicon-based sintered body and a glass ceramic sintered body.

  Examples of the resin used as a material for the insulating layer forming the frame 2 include an epoxy resin, a polyimide resin, an acrylic resin, a phenol resin, and a fluorine resin. Examples of the fluorine-based resin include a polyester resin and a tetrafluoroethylene resin.

  The insulating layer forming the frame 2 is formed by laminating a plurality of insulating layers made of the above-described materials. The insulating layer forming the frame 2 may be formed of two insulating layers as shown in FIG. 1, or may be formed of a single layer or three or more insulating layers. Although not shown, the size of the opening of the insulating layer forming the frame 2 may be varied to form a stepped portion on the upper surface, and a plurality of image sensor connection pads 3 may be provided on the stepped portion.

  In addition, external circuit connection electrodes are provided on the upper surface, side surfaces, or lower surface of the frame 2. The external circuit connection electrode is for electrically connecting the frame 2 and the flexible substrate 5, or the imaging element mounting substrate 1 and the external circuit board, or the imaging element mounting substrate and the external device.

  Inside the frame body 2 are provided internal wirings formed between insulating layers, and through conductors that connect the internal wirings up and down. These internal wirings or through conductors may be exposed on the surface of the frame 2. The external circuit connection electrode and the image sensor connection pad 3 may be electrically connected by the internal wiring or the through conductor.

  The imaging device connection pad 3, external circuit connection electrode, internal wiring, and through conductor are tungsten (W), molybdenum (Mo), manganese (Mn), silver when the frame 2 is made of electrically insulating ceramics. (Ag) or copper (Cu) or an alloy containing at least one metal material selected from these. In addition, when the frame 2 is made of resin, the imaging device connection pad 3, the external circuit connection electrode, the internal wiring, and the through conductor are copper (Cu), gold (Au), aluminum (Al), nickel ( Ni), chromium (Cr), molybdenum (Mo), titanium (Ti), or an alloy containing at least one metal material selected from these.

  A plating layer may be provided on the exposed surface of the imaging element connection pad 3, the external circuit connection electrode, the internal wiring, and the through conductor. According to this configuration, the imaging element connection pad 3, the external circuit connection electrode, the internal wiring, and the exposed surface of the through conductor can be protected to suppress oxidation. Moreover, according to this structure, the image pick-up element connection pad 3 and the image pick-up element 10 can be favorably electrically connected via the connecting member 13 such as wire bonding. As the plating layer, for example, a Ni plating layer having a thickness of 0.5 to 10 μm may be deposited, or even if this Ni plating layer and a gold (Au) plating layer having a thickness of 0.5 to 3 μm are sequentially deposited. Good.

  The frame 2 and the flexible substrate 5 are connected via an anisotropic conductive film 23. The anisotropic conductive film 23 is obtained by uniformly dispersing conductive particles in a thermosetting adhesive such as an anisotropic conductive resin (ACF) or an anisotropic conductive film (ACP). The anisotropic conductive film 23 is a bonding agent that has conductivity in the thickness direction to which force is applied, but does not exhibit conductivity in other cases.

  As a method for joining the flexible substrate 5 and the frame body 2, for example, the cutout portion 6 is provided on the upper surface of the flexible substrate 5, the conductive layer 7 is exposed, and the frame body 2 is joined via the anisotropic conductive film 23. The method is known.

In general, the notch portion 6 provided in the flexible substrate 5 is provided larger than the joint portion with the frame body 2 in consideration of manufacturing errors. In such a case, the conductive layer 7 where the notch 6 and the frame 2 do not overlap is covered with a protective material made of resin or the like, and heating to cure the protective material made of resin or the like is performed. Additional steps may be added. In general, the frame, the flat plate, and the external circuit board in the prior art have different coefficients of thermal expansion. From these facts, there is a possibility that the heat load is greatly applied to the joining portion by adding a heating process for curing the protective material, and there is a concern about peeling or deformation of each member. In particular, in the imaging device mounting substrate 1 and the imaging device 21 on which an imaging device that is required to be downsized in recent years is mounted, it is difficult to secure a bonding region, and there is a greater concern about peeling of the flexible substrate 5. ing.

On the other hand, in the example of the present embodiment shown in FIG. 1, the anisotropic conductive film 23 of the imaging element mounting substrate 1 covers the entire surface of the conductive layer 7 located in the notch portion 6. This makes it possible to protect the exposed conductive layer 7 of the flexible substrate 5 without providing a protective material made of resin or the like. Therefore, it is possible to reduce the process of heating for curing the protective material, and it is possible to reduce the thermal stress applied to the imaging element mounting substrate 1. Therefore, it becomes possible to reduce peeling or deformation of the members due to a large thermal load applied to the joining portion. In addition, this makes it possible to reduce the size of the imaging element mounting substrate 1 and the imaging device 21 while securing a bonding region between the members of the imaging element mounting substrate 1. Here, the members are the frame 2 and the flexible substrate 5 or the flexible substrate 5 and the flat plate 4.

  Further, the protective material made of resin or the like becomes liquid during the heating process, and may scoop up the side surface of the frame 2. At this time, if the frame 2 is thinned due to a recent demand for thinning, the protective material crawls up the side surface of the frame 2 to reach the upper surface of the frame 2 and the mounting area on the upper surface of the frame 2 There was a concern to reach. On the other hand, since the anisotropic conductive film 23 according to the present configuration is difficult to be liquefied even in the heating process, the possibility of scooping up the side surface of the frame body 2 can be reduced. Therefore, since the mounting area on the upper surface of the frame 2 can be secured, the image sensor mounting substrate 1 can be further downsized.

  Moreover, the outer edge of the flat plate 4 may be located outside the outer edge of the frame body 2 in a top view as in the present embodiment. In recent years, the thickness of the frame body 2 is also required to be reduced due to the demand for reducing the thickness of the imaging device 21. At this time, when an unintentional stress such as dropping from the outside is applied in the state of the device in which the imaging device 21 is incorporated or the imaging device 21 and the imaging element mounting substrate 1, the frame 2 is cracked. There has been a concern that the imaging device 21 malfunctions.

  Since the outer edge of the flat plate 4 is located outside the outer edge of the frame body 2 in a top view, it is possible to receive impact such as dropping by the flat plate 4 and reduce the impact on the frame body 2. As a result, it becomes possible to reduce the crack of the frame 2, etc. Further, when the outer peripheral edge of the flat plate 4 is positioned outside the outer peripheral edge of the frame body 2, the flat plate 4 may have a through hole or a notch in an outer region positioned outside the frame body 2. In this case, the through hole or the notch can be used as a marker for fixing the imaging device 21 and the external device, for example.

  Further, as in the present embodiment, the inner end of the anisotropic conductive film 23 may be provided at a position overlapping the first through hole 2a of the frame body 2 in a top view. The anisotropic conductive film 23 may be provided outside the first through hole 2 a of the frame body 2, that is, at a position overlapping the frame body 2 in a top view. Since the end portion of the anisotropic conductive film 23 is provided at a position overlapping the first through hole 2a of the frame body 2 in a top view, the bonding area between the frame body 2 and the flexible substrate 5 can be increased. Thus, the bonding strength can be further improved. Further, since the end portion of the anisotropic conductive film 23 is located outside the first through hole 2a of the frame body 2, an anisotropic process is performed in the pressurizing process for joining the frame body 2 and the flexible substrate 5. It is possible to reduce the fact that the conductive film 23 protrudes toward the first through hole 2a and the area of the image sensor mounting portion 11 becomes small.

  In addition, when the first through hole 2a of the frame 2 is rectangular, the anisotropic conductive film 23 is provided so as to avoid the corners of the opening in the top view, so that the frame 2 and the flexible substrate 5 are provided. In the pressurizing step for bonding, the anisotropic conductive film 23 accumulates at the corners of the first through holes 2a, so that it is possible to reduce the adhesion of moisture or dust to the portions.

  The anisotropic conductive film 23 may cover the side surface of the first through hole 2 a of the frame body 2 or the side surface of the second through hole 5 a of the flexible substrate 5. Thus, even when dust is generated from burrs or the like, it is possible to reduce the dust from adhering to the light receiving surface of the image sensor 10 by the anisotropic conductive film 23.

  The anisotropic conductive film 23 is black. Thus, it is possible to further reduce the light reflected by the surface of the conductive layer 7 of the flexible substrate 5 from reaching the light receiving surface side of the image sensor 10. Therefore, it is possible to reduce the occurrence of noise or the like in the image acquired by the imaging device 21.

  Next, the imaging device 21 will be described with reference to FIG. The imaging device 21 includes an imaging element mounting substrate 1 and an imaging element 10 mounted on the imaging element mounting portion 11 of the flat plate 4. Further, the imaging device 21 has a lid body 12 bonded to the upper surface of the imaging element mounting substrate 1. The image sensor 10 is mounted on the image sensor mounting portion 11, and the image sensor 10 is housed in a recess formed by the frame 2, the flexible substrate 5, and the flat plate 4.

  As the image sensor 10, for example, an image sensor such as a CCD type or a CMOS type is used. Each electrode of the imaging device 10 is electrically connected to the imaging device connection pad 3 by a connecting member 13 (bonding wire).

  Moreover, the image pick-up element 10 may be arrange | positioned on the upper surface of the flat plate 4 through the adhesive agent. As this adhesive, for example, silver epoxy or thermosetting resin is used.

  The lid body 12 has, for example, a flat plate shape. The lid 12 is made of a highly transparent member such as a glass material. The lid 12 is joined to the upper surface of the frame 2 by a joining member 14 such as a thermosetting resin or low-melting glass.

  The imaging device 21 of the present embodiment includes a highly reliable imaging element mounting substrate 1 that can reduce peeling between a frame and a flexible substrate or between a flexible substrate and a flat plate, or deformation thereof. The used imaging device 21 can be provided.

  Next, an example of a method for manufacturing the imaging element mounting substrate 1 of the present embodiment will be described. In addition, an example of the manufacturing method shown below is a manufacturing method using a multi-piece wiring board.

(1) First, a ceramic green sheet constituting the frame 2 is formed. For example, when obtaining the frame 2 which is an aluminum oxide (Al ₂ O ₃ ) -based sintered body, silica (SiO ₂ ), magnesia (MgO) or calcia (as a sintering aid) is added to the Al ₂ O ₃ powder. A powder such as CaO) is added, an appropriate binder, a solvent and a plasticizer are added, and then the mixture is kneaded to form a slurry. Thereafter, a ceramic green sheet for multi-piece production is obtained by a conventionally known forming method such as a doctor blade method or a calender roll method.

  When the frame 2 is made of, for example, a resin, the frame 2 can be formed by molding by a transfer molding method or an injection molding method using a mold that can be molded into a predetermined shape. .

  Moreover, the frame 2 may be obtained by impregnating a base material made of glass fiber with a resin, for example, glass epoxy resin. In this case, the frame body 2 can be formed by impregnating a base material made of glass fiber with an epoxy resin precursor and thermosetting the epoxy resin precursor at a predetermined temperature.

  (2) Next, by a screen printing method or the like, the ceramic green sheet obtained in the above step (1) is coated with metal on the portions to be the imaging device connection pad 3, the external circuit connection electrode, the internal wiring, and the through conductor. Apply or fill with paste.

  This metal paste is prepared by adjusting an appropriate viscosity by adding an appropriate solvent and binder to the metal powder made of the above-described metal material and kneading. The metal paste may contain glass or ceramics in order to increase the bonding strength with the frame 2.

(3) Next, the above-described green sheet is processed with a mold or the like. A first through hole 2 a is formed in the center of the green sheet that will be the frame 2.

  (4) Next, the ceramic green sheet laminated body used as the frame 2 is produced by laminating | stacking and pressing the ceramic green sheet used as each insulating layer. In this step, for example, a green sheet laminated body to be the frame body 2 may be manufactured by providing through holes in the green sheets to be the respective layers, and laminating and pressing both.

  (5) Next, this ceramic green sheet laminate is fired at a temperature of about 1500 to 1800 ° C. to obtain a multi-piece wiring board in which a plurality of frames 2 are arranged. In this step, the above-described metal paste is fired simultaneously with the ceramic green sheet to be the frame 2, and becomes the image sensor connection pad 3, the external circuit connection electrode, the internal wiring, and the through conductor.

  (6) Next, the multi-cavity wiring board obtained by firing is divided into a plurality of frames 2. In this division, a dividing groove is formed in a multi-piece wiring board along a portion serving as the outer edge of the frame body 2, and the frame body 2 is divided by a method of breaking along the dividing groove and dividing the frame body 2 or a slicing method. The method etc. which cut | disconnect along the location used as the outer edge of can be used. In addition, the dividing groove can be formed by cutting less than the thickness of the multi-piece wiring board with a slicing device after firing, but the cutter blade is pressed against the ceramic green sheet laminate for the multi-piece wiring board, You may form by cutting smaller than the thickness of a ceramic green sheet laminated body with a slicing apparatus.

(7) Next, the flexible substrate 5 to be bonded to the lower surface of the frame body 2 is prepared. First, a base film 5b made of polyimide is prepared. The conductive layer 7 is formed on the substrate by a step of forming a photoresist layer on the base film 5b, a DES (Development Etching Stripping) step, a screen printing method, or the like. Then, the flexible substrate 5 can be produced by passing the process of adhere | attaching the cover film 5c which consists of a polyimide film etc. on the upper surface of the conductive layer 7. FIG. At this time, the notch 6 can be provided by providing a hole larger than the second through hole 5a in the first cover film and exposing the conductive layer 7. Thereafter, the flexible substrate 5 can be manufactured by providing the second through hole 5a by using an etching method or a method of forming a shape with a mold in a predetermined place.

  (8) Next, the flat plate 4 to be bonded to the lower surface of the flexible substrate 5 is prepared. When the flat plate 4 is made of a metal material, the plate 4 is made of a plate material made of a metal material by punching or etching using a conventionally known stamping mold. In addition, even when made of other materials, it can be similarly produced by punching or the like suitable for each material. When the flat plate 4 is made of a metal material such as Fe-Ni-Co alloy, 42 alloy, Cu, or copper alloy, a nickel plating layer and a gold plating layer may be deposited on the surface. Thereby, the oxidative corrosion of the surface of the flat plate 4 can be effectively suppressed.

  Further, when the flat plate 4 is made of an electrically insulating ceramic or the like and a conductor pattern is printed on the surface, a nickel plating layer and a gold plating layer may be similarly applied to the surface. Thereby, the oxidative corrosion of the surface of the flat plate 4 can be effectively suppressed.

  (9) Next, the flexible substrate 5 and the flat plate 4 are bonded via the bonding material 15. As the bonding material 15, a paste-like thermosetting resin (adhesive member) is applied to one of the bonding surfaces of the flexible substrate 5 or the flat plate 4 by a screen printing method or a dispensing method. Then, after drying the thermosetting resin, the flexible substrate 5 and the flat plate 4 are overlapped, and then passed through a tunnel-type atmosphere furnace or oven, and heated and pressurized to heat the bonding material 15. The flexible substrate 5 and the flat plate 4 are firmly bonded.

  The bonding material 15 is made of, for example, a main agent made of bisphenol A type liquid epoxy resin, bisphenol F type liquid epoxy resin, phenol novolac type liquid resin, etc., a filler made of spherical silicon oxide or the like, and an acid anhydride such as tetrahydromethyl phthalic anhydride. It can be obtained by adding a carbon powder or the like as a curing agent mainly composed of a product or the like, and mixing or kneading with a centrifugal stirrer or the like to obtain a paste.

  In addition, as the bonding material 15, for example, bisphenol A type epoxy resin, bisphenol A modified epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, special novolac type epoxy resin, phenol Derivative epoxy resin, epoxy resin such as bisphenol skeleton type epoxy resin, etc. with addition of curing agent such as imidazole, amine, phosphorus, hydrazine, imidazole adduct, amine adduct, cationic polymerization or dicyandiamide Can be used.

  Further, the bonding material 15 may be the same member as the anisotropic conductive film 23, and when the bonding material 15 is the same member as the anisotropic conductive film 23, the step of bonding the frame 2 and the flexible substrate 5. It becomes possible to join together in one process.

  (10) Next, the external circuit connection electrode provided on the lower surface of the frame 2 and the conductive layer 7 exposed at the notch portion 6 of the flexible substrate 5 are joined via the anisotropic conductive film 23. . At this time, for example, the anisotropic conductive film 23 is applied to a predetermined position of the frame body 2 or the flexible substrate 5, pressed and heated, thereby joining the frame body 2 and the flexible substrate 5 to be electrically conductive. Can be made.

  The imaging element mounting substrate 1 can be manufactured by electrically joining the frame body 2 and the flexible substrate 5 as described above. Through the steps (1) to (10), the image sensor mounting substrate 1 is obtained. In addition, the process order of said (1)-(10) is not designated. For example, after joining the frame 2 and the flexible substrate 5, the flat plate 4 may be joined.

  The imaging device 21 can be manufactured by mounting the imaging device 10 on the imaging device mounting portion 11 of the imaging device mounting substrate 1 formed as described above and mounting the lid 12.

(Second Embodiment)
Next, an imaging element mounting substrate 1 and an imaging device 21 according to a second embodiment of the present invention will be described with reference to FIG.

  The imaging device 21 in the present embodiment is different from the imaging device 21 in the first embodiment in that the outer end portion of the anisotropic conductive film 23 is located outside the notch portion 6 of the flexible substrate 5 in a cross-sectional view. In other words, the outside of the anisotropic conductive film 23 in a sectional view is swollen.

In the present embodiment, the outer edge of the anisotropic conductive film 23 is located on the upper surface of the flexible substrate 5 excluding the notch 6. When the end face of the cover film 5c and the end face of the anisotropic conductive film 23 are connected, anisotropy occurs when a tensile stress is applied to the image pickup device mounting substrate 1 or when thermal expansion occurs due to thermal history. Stress is applied to the joint surface between the conductive film 23 and the end of the cover film 5c. At this time, peeling stress is applied to the end portion of the anisotropic conductive film 23, and a part of the end portion of the anisotropic conductive film 23 may be peeled off. Due to the peeling of the anisotropic conductive film 23, there is a concern that the airtightness between the frame 2 and the flexible substrate 5 is deteriorated, the protective property of the conductive layer 7 is deteriorated, and the like. As described above, the anisotropic conductive film 23 overlaps the cover film 5c in a top view, so that it is possible to reduce the peeling stress applied to the ends of the anisotropic conductive film 23 or the cover film 5c.

  Further, by providing the anisotropic conductive film 23 so as to overlap with the cover film 5c in a top view as in the present embodiment, the conductive layer 7 can be covered with the anisotropic conductive film 23 even if there is a process error. It becomes possible. As a result, the protection of the conductive layer 7 can be further improved. Further, if there is even a slight gap between the cover film 5c and the anisotropic conductive film 23, moisture or dust or the like enters between the cover film 5c and the base film 5b or between the cover film 5c and the conductive layer 7, and the cover The film 5c may be peeled off. At this time, by providing the anisotropic conductive film 23 so as to overlap with the cover film 5c in a top view, it is possible to cover the end portion of the cover film 5c, and to reduce peeling of the cover film 5c. .

  Further, as in the present embodiment, the outer edge of the flexible substrate 5 may be located outside the frame body 2 in a top view. In general, in recent years, the thickness of the frame body 2 is also required to be reduced due to the demand for reducing the thickness of the imaging device 21. At this time, in the state of the device incorporating the image pickup device 21 or the image pickup device 21 and the image pickup device mounting substrate 1, when unintentional stress such as dropping from the outside is applied, the frame 2 is cracked, cracked, etc. There is a concern that the imaging device 21 malfunctions. Since the outer edge of the flexible substrate 5 is positioned outside the outer edge of the frame body 2 in a top view, the flexible substrate 5 can receive an impact such as a drop in a role as a relaxation agent. Therefore, it is possible to reduce the impact on the frame body 2, and it is possible to reduce the cracks of the frame body 2.

  Moreover, the inner edge part of the flexible substrate 5 may be provided outside the first through hole 2a of the frame body 2 when viewed from above, that is, at a position overlapping the frame body 2 when viewed from above. It may be provided at a position overlapping the second first through hole 2a. Since the end portion of the flexible substrate 5 is located outside the first through hole 2a of the frame body 2, the inner side surface of the second through hole 5a of the flexible substrate 5 is directed to the first through hole 2a side in the process error or the like. Protruding and reducing the area of the image sensor mounting portion 11 can be reduced. In addition, since the end portion of the flexible substrate 5 is provided at a position overlapping the first through hole 2a of the frame body 2 in a top view, the bonding area between the frame body 2 and the flexible substrate 5 can be maximized. Thus, the bonding strength can be further improved.

  As a method for producing such an image pickup device mounting substrate 1, for example, an anisotropic conductive film 23 is applied to the flexible substrate 5 more than usual and reaches the cover film 5c, and is bonded while applying a large pressure. Can be produced.

(Third embodiment)
Next, an imaging element mounting substrate 1 and an imaging apparatus 21 according to a third embodiment of the present invention will be described with reference to FIG.

  The imaging device 21 in the present embodiment is different from the imaging device 21 in the second embodiment in that the outer shape of the anisotropic conductive film 23 is different in a cross-sectional view.

  In the present embodiment shown in FIG. 3, the outer edge of the anisotropic conductive film 23 is located on the upper surface of the flexible substrate 5 excluding the notch 6, and the anisotropy of the portion that does not overlap with the frame 2 in top view. The upper surface of the conductive film 23 is horizontal. As described above, since the upper surface of the anisotropic conductive film 23 that does not overlap the frame 2 is horizontal, the trapping of dust or moisture in the anisotropic conductive film 23 can be reduced. It becomes. Therefore, it is possible to maintain a good surface state of the anisotropic conductive film 23, and it is possible to improve the long-term reliability of the imaging element mounting substrate 1.

  In addition, since the upper surface of the anisotropic conductive film 23 that does not overlap the frame 2 is horizontal, the design of parasitic capacitance and the like for the conductive layer 7 becomes easier. Therefore, it is possible to improve the electrical characteristics of the imaging element mounting substrate 1.

  Moreover, the outer edge of the flexible substrate 5 may be located inside the frame body 2 in a top view. Thereby, it can reduce that the outer edge of the flexible substrate 5 is located outside the frame body 2 in a top view due to a process error or the like, and the mounting area of the imaging device 21 and the imaging device 21 can be further downsized. It becomes possible.

(Fourth embodiment)
Next, an imaging element mounting substrate 1 and an imaging device 21 according to a fourth embodiment of the present invention will be described with reference to FIG.

  The imaging device 21 in the present embodiment is different from the imaging device 21 in the second embodiment in that the flexible substrate 5 has a first cutout portion 6a and a second cutout portion 6b. The frame body 2, the flexible substrate 5, and the flat plate 4 are joined together by an anisotropic conductive film 23.

In the present embodiment shown in FIG. 4, the flat plate 4 has an image sensor mounting portion 11 in the central region of the upper surface. The flexible substrate 5 is connected to a peripheral region on the flat plate 4 and surrounding the central region. A part of the flexible substrate 5 extends outward, and a plurality of conductive layers 7 are formed inside, and the central region side is cut on the upper surface. A first cutout portion 6a where the uppermost conductive layer 7a of the plurality of conductive layers 7 is located, and a lowermost conductive layer 7b of the plurality of conductive layers 7 cut out toward the central region on the lower surface. It has the 2nd notch part 6b located. The frame body 2 is continuously provided along the peripheral region from the first cutout portion 6 a of the flexible substrate 5, and surrounds the imaging element mounting portion 11. The frame 2 and the flexible substrate 5 are connected via a first anisotropic conductive film 23a, and the first anisotropic conductive film 23a covers the surface of the uppermost conductive layer 7a located in the first notch 6a. The flexible substrate 5 and the flat plate 4 are all connected to each other through the second anisotropic conductive film 23b, and the second anisotropic conductive film 23b is formed on the lowermost conductive layer 7b located in the second notch 6b. Covers the entire surface.

  When the flat plate 4 is made of a metal material or has a conductor layer on the surface, the flat plate 4 and the flexible substrate 5 may be electrically connected by noise countermeasures or the like. At this time, the flexible substrate 5 of the imaging element mounting substrate 1 is bonded to the upper surface and the lower surface of the frame body 2 and the flat plate 4 by the anisotropic conductive film 23, so It becomes easy to make the tensile stress uniform. Therefore, the balance of the tensile stress applied to the flexible substrate 5 is improved, and it is possible to reduce the occurrence of deformation in the flexible substrate 5 according to the difference in tensile stress of the bonding material.

  Further, the first anisotropic conductive film 23a and the second anisotropic conductive film 23b are respectively covered with the uppermost conductive layer 7a and the lowermost conductive layer 7b, thereby providing a protective material made of resin or the like. Thus, the exposed uppermost conductive layer 7a and lowermost conductive layer 7b of the flexible substrate 5 can be protected. Accordingly, it is possible to reduce the step of performing heating for curing the protective material. It is possible to reduce the thermal stress applied to the imaging element mounting substrate 1 and to reduce the occurrence of deformation according to the difference in the tensile stress of the bonding material applied to the flexible substrate 5. Therefore, it becomes possible to further reduce the peeling or deformation of the members due to the fact that the tensile stress due to the thermal load and the bonding material is greatly applied to the bonded portion.

As the flat plate 4 in the present embodiment, a plate in which a conductor is printed on the surface of a base material made of a metal material or an electrically insulating ceramic is used. When the flat plate 4 is made of electrically insulating ceramic or the like, it may have a conductor layer inside, and the conductor layer provided on the surface may be connected to the conductor layer provided inside. .

  The manufacturing method and constituent materials of the flexible substrate 5 in the present embodiment are basically the same as those of the flexible substrate 5 described in the first embodiment except that the second notch 6b is provided on the lower surface. The flexible substrate 5 has a plurality of conductive layers 7, and the flexible substrate 5 is provided with a plurality of conductive layers 7 inside and through conductors that connect the plurality of conductive layers 7 up and down. It may be. Further, the uppermost conductive layer 7a and the lowermost conductive layer 7b may be electrically connected via these. The exposed surfaces of the uppermost conductive layer 7a and the lowermost conductive layer 7b may be provided with a plating layer. The flexible substrate 5 is covered with the first cover film 5d except for the portion that overlaps the first cutout portion 6a of the uppermost conductive layer 7a, and overlaps the second cutout portion 6b of the lowermost conductive layer 7b. The portions other than the portion are covered with the second cover film 5e.

  The first anisotropic conductive film 23a and the second anisotropic conductive film 23b are black so that the light reflected on the surfaces of the uppermost conductive layer 7a and the lowermost conductive layer 7b of the flexible substrate 5 can be reflected. It is possible to effectively reduce irregular reflection at the gap between the joints and reaching the light receiving surface side of the image sensor 10. Therefore, the image acquired by the imaging device 21 can be made better.

  Further, when the flexible substrate 5 includes the first cover film 5d and the second cover film 5e, the inner end portion of the first cover film 5d and the end portion of the second cover film 5e are provided at positions where they do not overlap with each other when viewed from above. Also good. This makes it easy to ensure the rigidity of the flexible substrate 5. Therefore, it is possible to reduce the occurrence of peeling due to the stress caused by the flexible substrate 5 being bent excessively on the first anisotropic conductive film 23a and the second anisotropic conductive film 23b.

(Fifth embodiment)
Next, an imaging element mounting substrate 1 and an imaging apparatus 21 according to a fifth embodiment of the present invention will be described with reference to FIG.

  The imaging device 21 in the present embodiment is different from the imaging device 21 in the fourth embodiment in that the outer end portions of the first anisotropic conductive film 23a and the second anisotropic conductive film 23b are flexible substrates in a cross-sectional view. 5 is located outside the first notch 6a or the second notch 6b.

  In the present embodiment shown in FIG. 5, the outer edge of the first anisotropic conductive film 23a is located on the upper surface of the flexible substrate 5 excluding the first notch 6a, and the second anisotropic conductive film 23b The outer edge is located on the surface of the flexible substrate 5 excluding the second notch 6b. Peeling stress that may be applied when the end face of the first cover film 5d or the second cover film 5e is connected to the end face of the first anisotropic conductive film 23a or the second anisotropic conductive film 23b Can be reduced. Therefore, the bonding strength between the first anisotropic conductive film 23a and the second anisotropic conductive film 23b can be improved.

  Further, by providing the first anisotropic conductive film 23a or the second anisotropic conductive film 23b so as to overlap the first cover film 5d or the second cover film 5e in a top view, the first anisotropic conductive film 23a or the second anisotropic conductive film 23b is caused by a process error. It can be reduced that the conductive film 23a or the second anisotropic conductive film 23b does not cover the uppermost conductive layer 7a or the lowermost conductive layer 7b. This makes it possible to further improve the protection of the uppermost conductive layer 7a or the lowermost conductive layer 7b.

  In addition, if there is even a slight gap between the first cover film 5d or the second cover film 5e and the first anisotropic conductive film 23a or the second anisotropic conductive film 23b, moisture, dust or the like is first. The cover film 5d or the second cover film 5e and the base film 5b, or the first cover film 5d or the second cover film 5e and the uppermost conductive layer 7a or the lowermost conductive layer 7b enter the first cover film. There is a possibility that peeling of 5d or the second cover film 5e occurs. At this time, the first cover film 5d or the second cover film 5e and the first anisotropic conductive film 23a or the second anisotropic conductive film 23b are provided so as to overlap with each other in a top view. The end portion of the second cover film 5e can be covered, and the bonding strength of the first cover film 5d or the second cover film 5e can be improved.

  Further, when the flexible substrate 5 includes the first cover film 5d and the second cover film 5e, the inner end portion of the first cover film 5d and the end portion of the second cover film 5e may be provided at a position where they overlap each other in a top view. Good. As a result, the deformation or tensile stress in the thermal expansion or the like between the first anisotropic conductive film 23 a and the second anisotropic conductive film 23 b can be easily made uniform between the upper surface and the lower surface of the flexible substrate 5. Therefore, the balance of the tensile stress applied to the flexible substrate 5 is improved, and it is possible to reduce the occurrence of deformation in the flexible substrate 5 according to the difference in tensile stress of the bonding material.

  In addition, this invention is not limited to the example of the above-mentioned embodiment, Various modifications, such as a numerical value, are possible.

  Further, for example, in the example of the present embodiment shown in FIGS. 1 to 5, the shape of the imaging element connection pad 3, or the first through hole 2 a or the second through hole 5 a is a rectangular shape, but a circular shape or the like It may be a polygonal shape. In addition, the arrangement, number, shape, and the like of the image sensor connection pad 3 in the present embodiment are not specified. Further, various combinations of the characteristic portions in the present embodiment are not limited to the above-described embodiments.

DESCRIPTION OF SYMBOLS 1 ...... Image sensor mounting substrate 2 ... Frame body 2a ... 1st through-hole 3 ... Image sensor connection pad 4 ... Flat plate 5 ... Flexible substrate 5a .... Second through hole 5b ... Base film 5c ... Cover film 5d ... First cover film 5e ... Second cover film 6 ... Notch 6a ... First notch Part 6b ... second cutout part 7 ... conductive layer 7a ... uppermost conductive layer 7b ... lowermost conductive layer 10 ... imaging element 11 ... imaging element mounting part 12 ... Lid 13 ... Connection member 14 ... Joining member 15 ... Joining material 21 ... Imaging device 23 ... Anisotropic conductive film 23a ... First anisotropic conductive film 23b ...・ Second anisotropic conductive film

Claims (7)

A flat plate having an image sensor mounting portion in the central region of the upper surface;
Connected to a peripheral region on the flat plate and surrounding the central region, a part of the conductive layer extends outward, and a conductive layer is formed inside, and the central region side is cut out on the upper surface to form the conductive layer. A flexible substrate having a notch located;
A frame body that is provided continuously from the cutout portion of the flexible substrate along the peripheral region, and surrounds the imaging element mounting portion;
The frame body and the flexible substrate are connected via an anisotropic conductive film, and the anisotropic conductive film covers the entire surface of the conductive layer located in the notch. Device mounting board.   The imaging element mounting substrate according to claim 1, wherein an outer edge of the anisotropic conductive film is located on an upper surface of the flexible substrate excluding the notch.   The imaging element mounting substrate according to claim 1, wherein the anisotropic conductive film is black. A flat plate having an image sensor mounting portion in the central region of the upper surface;
Connected to a peripheral region on the flat plate and surrounding the central region, a part thereof extends outward, a plurality of conductive layers are formed therein, and the central region side is cut out on the upper surface. A first notch where the uppermost conductive layer is located, and a second notch where the lowermost conductive layer of the plurality of conductive layers is located on the lower surface. A flexible substrate having a portion;
A frame body that is continuously provided along the peripheral region from the first cutout portion of the flexible substrate, and surrounds the imaging element mounting portion;
The frame and the flexible substrate are connected via a first anisotropic conductive film, and the first anisotropic conductive film covers the entire surface of the uppermost conductive layer located in the first notch. Covering,
The flexible substrate and the flat plate are connected via a second anisotropic conductive film, and the second anisotropic conductive film covers the entire surface of the lowermost conductive layer located at the second notch. A substrate for mounting an image pickup element, The outer edge of the first anisotropic conductive film is located on the upper surface of the flexible substrate excluding the first notch,
The imaging element mounting substrate according to claim 4, wherein an outer edge of the second anisotropic conductive film is located on a lower surface of the flexible substrate excluding the second notch portion.   The imaging element mounting substrate according to claim 4, wherein the first anisotropic conductive film and the second anisotropic conductive film are black. The imaging device mounting substrate according to any one of claims 1 to 6,
An imaging device comprising: an imaging device mounted on the imaging device mounting portion of the flat plate of the imaging device mounting substrate.

Images