JP2017152521A - Board for mounting image pick-up device and imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a board for mounting an image pick-up device capable of reducing exfoliation of a wiring board and an external circuit board, and to provide an imaging device.SOLUTION: A board for mounting an image pick-up device includes an inorganic board 4 having a central region 4b above which an image pick-up device 10 is placed, and a peripheral region 4a surrounding the central region 4b, a wiring board 2 provided above the peripheral region 4a of the inorganic board 4 so as to surround the central region 4b, where the outer edge is like a frame larger than the inorganic board 4, and having a notch 2a cut out from the side face to the lower surface, and a sheet-like external circuit board 5 connected with the notch 2a of the wiring board 2. The external circuit board 5 is connected with the wiring board 2, via a joint material 16 formed from the side face to the upper surface.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wiring board and an imaging apparatus on which an imaging element such as a CCD (Charge Coupled Device) type or a CMOS (Complementary Metal Oxide Semiconductor) type is mounted.

  2. Description of the Related Art Conventionally, there has been known an image sensor mounting substrate including an inorganic substrate and a wiring substrate having an opening. The inorganic substrate and the wiring substrate are generally bonded by a bonding material. Such an image sensor mounting board is connected to an external circuit board made of FPC or the like and the upper or lower surface of the wiring board. An imaging device in which an imaging element is mounted on the imaging element mounting substrate is known.

JP-A-4-27929

  The module on which the imaging device is mounted is mounted on a device that is always carried, such as a portable terminal. Therefore, various vibrations are applied to the imaging apparatus from the outside depending on the use state of the device. However, recent image pickup devices have a reduced bonding area between the wiring board and the external circuit board due to a demand for miniaturization, and it has been difficult to provide a large bonding strength between the wiring board and the external circuit board. As a result, in the imaging apparatus, there is a concern that the wiring board and the external circuit board may be peeled off.

  An object of the present invention is to provide an imaging element mounting substrate and an imaging apparatus that can suppress the occurrence of peeling between a wiring board of an imaging apparatus and an external circuit board.

  An image sensor mounting substrate according to an aspect of the present invention is provided on a central region in which an image sensor is disposed above, an inorganic substrate having a peripheral region surrounding the central region, and the peripheral region of the inorganic substrate. A wiring board that surrounds the central region and has an outer edge that is larger than the inorganic board and has a notch cut out from a side surface to a lower surface, and is connected to the notch of the wiring board A sheet-like external circuit board, and the external circuit board is connected to the wiring board via a joining member formed from a side surface to an upper surface.

An imaging device according to one aspect of the present invention includes an imaging device mounted on the central region of the inorganic substrate of the imaging device mounting substrate.

An image sensor mounting substrate according to one aspect of the present invention is provided on a central region in which an image sensor is disposed above, an inorganic substrate having a peripheral region surrounding the central region, and a peripheral region of the inorganic substrate. A circuit board that surrounds the region and has a frame shape whose outer edge is larger than that of the inorganic substrate and has a notch cut from the side surface to the lower surface, and a sheet-like external circuit connected to the notch portion of the circuit board The external circuit board is connected to the wiring board via a bonding member formed from the side surface to the upper surface.

  Thereby, it becomes possible to form the fillet of the bonding material between the wiring board and the side wall of the external circuit board. Therefore, it is possible to provide an imaging element mounting substrate and an imaging apparatus that can reduce peeling between the wiring board and the external circuit board.

(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 1st Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the BB line of (a). is there. (A) And (b) is a bottom view which shows the external appearance of the image pick-up element mounting board | substrate and imaging device which concern on the other aspect of the 1st Embodiment of this invention. (A) And (b) is a bottom view which shows the external appearance of the image pick-up element mounting board | substrate and imaging device which concern on the other aspect of the 1st Embodiment of this invention. (A) is a top view which shows the external appearance of the imaging device which concerns on the other aspect of the 1st Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the AA line of (a). (A) is a top view which shows the external appearance of the imaging device which concerns on the other aspect of the 1st Embodiment of this invention, (b) is a longitudinal cross-sectional view corresponding to the AA line of (a). (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. (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 6th 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 7th 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 the following description, an image pickup apparatus has a configuration in which an image pickup element is mounted on an image pickup element mounting substrate and a lens holder is bonded to the upper surface of the image pickup element mounting substrate. 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)
The imaging device 21 and the imaging element mounting substrate 1 according to the first embodiment of the present invention will be described with reference to FIGS. The imaging device 21 in the present embodiment includes the imaging device mounting substrate 1, the imaging device 10, and the lens holder 19, but the lens holder 19 is omitted in FIGS.

  The image element mounting substrate 1 is provided on the central region 4b in which the imaging element 10 is disposed above, the inorganic substrate 4 having the peripheral region 4a surrounding the central region 4b, and the peripheral region 4a of the inorganic substrate 4, Surrounding the region 4b, the outer edge is larger than the inorganic substrate 4, and has a cutout portion 2a cut out from the side surface to the lower surface, and connected to the cutout portion 2a of the wiring substrate 2. The external circuit board 5 is connected to the wiring board 2 via a bonding material 16 formed from the side surface to the upper surface.

  The imaging element mounting substrate 1 has an inorganic substrate 4 having a central area 4b in which the imaging element 10 is disposed above and a peripheral area 4a surrounding the central area 4b.

  Here, the central region 4b is a region surrounded by the peripheral region 4a. The central region 4 b may be provided in the vicinity of the central portion of the inorganic substrate 4 or may be provided at a position eccentric from the central portion of the inorganic substrate 4. The peripheral region 4 a is a region on the inorganic substrate 4 that surrounds the central region 4 b and is a region along the outer edge of the inorganic substrate 4.

  As the material constituting the inorganic substrate 4, for example, a material having a high thermal conductivity is used. Examples of the material for forming the inorganic substrate 4 include an aluminum nitride sintered body, a silicon nitride sintered body, or silicon (Si). In addition, when the material for forming the inorganic substrate 4 is, for example, an aluminum nitride crystal or a silicon nitride chamber crystal, the inorganic substrate 4 may be a laminate including a plurality of insulating layers. In addition, the inorganic substrate 4 may have a conductive layer deposited on the surface of a laminate composed of a plurality of insulating layers. In addition, the image sensor 10 is mounted on the central region 4 b located on the upper surface of the inorganic substrate 4.

Moreover, a metal material is also used as the material of the inorganic substrate 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 wiring board 2 is an aluminum oxide sintered body having a thermal expansion coefficient of about 5 × 10 ⁻⁶ / ° C. to 10 × 10 ⁻⁶ / ° C., the inorganic substrate 4 is about 10 × 10 ⁻⁶ / ° C. Stainless steel (SUS304) having a thermal expansion coefficient of In this case, the difference in thermal contraction and thermal expansion between the wiring substrate 2 and the inorganic substrate 4 is reduced, so that deformation of the central region 4b 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 inorganic substrate 4 is made of a metal material, it is possible to reduce the magnetization of the inorganic substrate 4 due to the nonmagnetic material. Accordingly, for example, when a magnet or an electromagnet is used for an external device such as a lens drive, it is possible to reduce the inorganic substrate 4 from hindering the function of the external device such as a lens drive due to the magnetism of the inorganic substrate 4. Become.

  For example, a CCD (Charge Coupled Device) type or a CMOS (Complementary Metal Oxide Semiconductor) type is used as the imaging element 10. In addition, the image pick-up element 10 may be arrange | positioned on the upper surface of the inorganic board | substrate 4 through the adhesive material. For example, silver epoxy or thermosetting resin is used as the adhesive.

  The image pickup device mounting substrate 1 is provided on the peripheral region 4a of the inorganic substrate 4, surrounds the central region 4b, has a frame shape whose outer edge is larger than the inorganic substrate 4, and is cut out from the side surface to the lower surface. A wiring board 2 having a portion 2a is provided.

  The wiring board 2 may be made of an insulating layer, and an imaging element connection pad 3 may be provided on the upper surface. Although not shown, a plurality of external circuit connection electrodes connected to the external circuit or the inorganic substrate 4 may be provided on the lower surface of the wiring board 2. For example, electrically insulating ceramics or resin (plastics) is used as the material of the insulating layer constituting the wiring board 2.

  Examples of the electrically insulating ceramic used as the material of the insulating layer forming the wiring substrate 2 include 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 the material for the insulating layer forming the wiring board 2 include epoxy resin, polyimide resin, acrylic resin, phenol resin, and fluorine resin. Examples of the fluorine-based resin include a polyester resin and a tetrafluoroethylene resin.

  As shown in FIGS. 1 to 6, the outer edge of the inorganic substrate 4 may be located inside or at the same position as the outer edge of the wiring substrate 2 in a top view. Since the outer edge of the inorganic substrate 4 is located on the inner side or at the same position as the outer edge of the wiring substrate 2 in a top view, the imaging device 21 can be reduced in size. Moreover, when connecting the imaging device 21 to an external module, it is possible to reduce the possibility of damaging the wiring or the like at the end of the inorganic substrate 4.

  The insulating layer forming the wiring board 2 may be formed by laminating a plurality of insulating layers made of the above-described materials. The insulating layer forming the wiring board 2 may be formed of four insulating layers as shown in FIGS. 1 to 2, or may be formed of a single layer to three layers or five or more insulating layers. Also good. In addition, as in the example shown in FIGS. 1 to 2, the size of the opening of the insulating layer forming the wiring substrate 2 is varied to form a stepped portion on the upper surface, and a plurality of image sensor connection pads 3 are formed on the stepped portion. May be provided.

  In addition, an external circuit connection electrode may be provided on the upper surface, side surface, or lower surface of the wiring board 2. The external circuit connection electrode is for electrically connecting the wiring board 2 and the external circuit board or the imaging device 21 and the external circuit board.

  Inside the wiring board 2, an internal wiring formed between the insulating layers and a through conductor that connects the internal wirings up and down are provided. These internal wirings or through conductors may be exposed on the surface of the wiring board 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, the external circuit connection electrode, the internal wiring, and the through conductor are tungsten (W), molybdenum (Mo), manganese (Mn), silver when the wiring board 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 wiring board 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), 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 wiring board 2 may be provided with a lid 12 on the upper surface for sealing. 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 wiring board 2 by a joining member 14 such as a brazing material made of a thermosetting resin, low melting point glass, or a metal component.

  The wiring board 2 has a notch 2a. When the notch 2a, for example, the wiring board 2 is composed of a plurality of insulating layers, a plurality of insulating layers whose outer edges are located on the inner side of the outer edge of the wiring board 2 may be provided. Further, for example, the wiring board 2 may be created by pressing with a mold or the like.

  The imaging element mounting substrate 1 includes a sheet-like external circuit substrate 5 connected to the notch 2 a of the wiring substrate 2.

Examples of the sheet-like external circuit board 5 include FPC. For example, when the sheet-like external circuit board 5 is FPC (Flexible Printed Circuits), it has a base film. As a material for forming the base film, an insulator made of a resin such as a polyimide film is used. The external circuit board 5 has a conductive layer on the upper surface of the base film. The conductive layer is made of copper, aluminum, gold, nickel, or an alloy containing at least one metal material selected from these.

  A plating layer may be provided on the exposed surface of the conductive layer. According to this configuration, the exposed surface of the conductive layer can be protected and oxidation can be suppressed. Moreover, according to this structure, the electrical connection of the electrical connection of the wiring board 2 and a conductive layer 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.

  For example, when the external circuit board 5 is an FPC, the external circuit board 5 has a cover film provided on the upper surface of the conductive layer. The cover film is a film for protecting the surface of the conductive layer, and an adhesive is applied to one surface of a film made of a resin material such as a polyimide film, and is applied to the surface of the conductive layer other than the portion that is electrically joined to the wiring board 2. Is provided.

  The external circuit board 5 of the imaging element mounting board 1 is connected to the wiring board 2 via a bonding material 16 formed from the side surface to the upper surface.

  In general, the module on which the imaging device 21 is mounted is mounted on a device that is always carried, such as a portable terminal. Therefore, various vibrations are applied to the imaging device 21 from the outside depending on the use state of the device. However, in recent years, the imaging device 21 has a reduced bonding area between the wiring board 2 and the external circuit board 5 due to a demand for miniaturization, and it is difficult to maintain the bonding strength between the wiring board 2 and the external circuit board 5. It was. Thereby, in the imaging device 21, there is a concern that the wiring board 2 and the external circuit board 5 may be peeled off. On the other hand, the wiring board 2 of the image pickup device mounting board 1 has a notch, and the external circuit board 5 has a bonding material 16 formed from the side surface to the upper surface. It becomes possible to form a fillet of the bonding material 16 between the side wall of the notch 2a and the external circuit board 5, and it is possible to provide a large fillet itself. Therefore, peeling between the wiring board 2 and the external circuit board 5 can be reduced.

The bonding material 16 for bonding the external circuit board 5 and the wiring board 2 is made of a material that is not easily denatured by heat applied in the mounting process of the imaging element 10. Such a bonding material 16 and an adhesive member are bisphenol A liquid epoxy resin or polyimide resin. In this case, it is possible to satisfactorily prevent the external circuit board 5 and the wiring board 2 from being peeled off in the mounting process of the image sensor 10. Further, the bonding material 16, the connecting material 18 or the adhesive member may be conductive, and the external circuit board 5 and the wiring board 2 or the wiring board 2 and the inorganic board 4 may be electrically bonded. The conductive connecting material 18 is, for example, solder, gold bumps, silver epoxy, or the like. The conductive bonding material 16 is, for example, an anisotropic conductive resin (ACF) or an anisotropic conductive paste (ACP). Examples of the conductive adhesive member include solder, gold bump, silver epoxy, anisotropic conductive resin (ACF), and anisotropic conductive film (ACP).

  The bonding material 16 may be non-conductive as in the example shown in FIGS. In the example shown in FIG. 1, the wiring board 2 and the external circuit board 5 are electrically connected to the exposed electrode pad of the wiring board 2 and the exposed electrode of the external circuit board 5 by a connecting material 18. At this time, the bonding material 16 serves as a sealing material, and improves the bonding strength between the external circuit board 5 and the wiring board 2 by forming notches 2a and fillets of the wiring board 2 while improving the bonding strength. 18 can be prevented from being deteriorated.

  Further, as in the example shown in FIG. 2, the bonding material 16 may be provided at a place where the wiring board 2 and the external circuit board 5 are not electrically joined, that is, a place where there is no electrode pad on the wiring board 2 and the external circuit board 5. preferable. As a result, the bonding strength between the wiring board 2 and the external circuit board 5 can be further increased, and the peeling between the wiring board 2 and the external circuit board 5 can be reduced. Furthermore, since the bonding material 16 extruded due to the presence of the connecting material 18 is accumulated at a place where the connecting member 18 is not present, the outer edge of the bonding material 16 is located outside the outer edge of the wiring board 2 in a top view. It can be reduced.

  3 to 4 are plan views of the imaging element mounting substrate 1 according to another aspect of the present embodiment.

  The notch 2a provided on the wiring board 2 may be provided on the entire side as shown in FIGS. 3 (a) and 4 (a), or as in the example shown in FIGS. 3 (b) and 4 (b). Alternatively, the external circuit board 5 may be provided so as to surround it.

  As shown in FIG. 3A, the notch 2a is provided on one entire side, so that the bonding material 16 widens the fillet as shown in FIG. 4A and increases the area of the bonding surface with the wiring board 2. It can be provided. Therefore, even if the external circuit board 5 vibrates in the vertical direction of FIGS. 3A and 4A, it is possible to further reduce the occurrence of peeling starting from the end point of the bonding material 16.

  3B, the notch 2a of the wiring board 2 is provided so as to surround the external circuit board 5, so that the bonding material 16 of the external circuit board 5 is provided as shown in FIG. It can be provided over a plurality of sides. Therefore, it is possible to reduce peeling of the wiring board 2 and the external circuit board 5 against vibrations from various directions. 3B and 4B, the notch 2a is provided so as to surround the external circuit board 5, so that the bonding material 16 protrudes from the outer edge of the wiring board 2. As shown in FIG. It is possible to reduce this. Further, since the notch 2a surrounds the external circuit board 5, it is easy to provide a thickness to the fillet formed by the bonding material 16. This makes it possible to further improve the bonding strength.

  Further, as in the example shown in FIG. 4B, by providing the notch 2a so as to surround the external circuit board 5, the side surface of the notch 2a, that is, the external circuit board 5 in FIG. The bonding material 16 can form a fillet even in the upper and lower portions sandwiched. Therefore, the bonding strength between the wiring board 2 and the external circuit board 5 can be further improved.

  5 to 6 show the imaging device 21 in which the lens holder 19 is not omitted. The imaging device 21 includes a lens holder 19 provided on the upper surface of the imaging element mounting substrate 1. The imaging device 21 includes an imaging element mounting substrate 1 and an imaging element 10 mounted on the central region 4b of the inorganic substrate 4 of the imaging element mounting substrate 1.

As in the example illustrated in FIGS. 5 to 6, the imaging device 21 may include a lens holder 19. By having the lens holder 19, it is possible to improve airtightness or reduce the external stress being directly applied to the imaging device 21. The lens holder 19 is formed by bonding, for example, a housing made of resin or the like and one or more lenses made of resin, liquid, glass, crystal, or the like to the housing. Further, the lens holder 19 may be electrically connected to the wiring board 2 with a driving device for driving the lens up and down and left and right.

  The lens holder 19 may be connected to the upper surface of the wiring board 2 as in the example shown in FIG. 5, or may be provided on the upper surface of the lid 12 as in the example shown in FIG. Since the lens holder 19 is connected to the upper surface of the wiring board 2 as in the example shown in FIG. 5, it is easy to electrically connect the lens holder 19 and the wiring board 2. Further, since the lens holder 19 is provided on the upper surface of the lid 12 as in the example shown in FIG. 6, the joining area of the lens holder 19 can be further reduced. Therefore, the imaging device 21 can be downsized.

  Next, an example of a method for manufacturing the imaging element mounting substrate 1 and the imaging device 21 according to the present embodiment will be described. In addition, an example of the manufacturing method shown below is a manufacturing method using many wiring boards 2 and using the wiring board.

(1) First, a ceramic green sheet constituting the wiring board 2 is formed. For example, when obtaining the wiring board 2 which is an aluminum oxide (Al ₂ O ₃ ) sintered material, 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 wiring board 2 is made of, for example, a resin, the wiring board 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 wiring board 2 may be obtained by impregnating a base material made of glass fiber with a resin, such as glass epoxy resin. In this case, the wiring board 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 wiring board 2.

  (3) Next, the above-described green sheet is processed with a mold or the like. An opening is formed in the central region of the green sheet to be the wiring board 2. At this time, the notch 2a may be formed.

(4) Next, the ceramic green sheets used as the wiring board 2 are produced by laminating and pressing the ceramic green sheets used as the insulating layers. Further, in this step, for example, a green sheet laminated body to be the wiring board 2 may be manufactured by providing through holes in the green sheets to be the respective layers, and laminating and pressing both. At this time, a hole or notch may be formed at a predetermined position of the plurality of ceramic green sheets using a mold or the like, and these may be laminated to create the notch 2a.

  (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 wiring boards 2 are arranged. In this step, the above-described metal paste is fired simultaneously with the ceramic green sheet to be the wiring substrate 2, and becomes the imaging element 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 wiring boards 2. In this division, a dividing groove is formed in a multi-piece wiring board along a portion serving as an outer edge of the wiring board 2, and the wiring board 2 is divided by a method of breaking and dividing along the dividing groove 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, an inorganic substrate 4 to be bonded to the lower surface of the wiring substrate 2 is prepared. When the inorganic substrate 4 is made of a metal material, the inorganic substrate 4 is produced by punching or etching using a conventionally known stamping mold on a plate made of the metal material. In addition, even when made of other materials, it can be similarly produced by punching or the like suitable for each material. Moreover, when the inorganic substrate 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 thereof. . Thereby, the oxidative corrosion of the surface of the inorganic substrate 4 can be effectively suppressed.

  Further, when the inorganic substrate 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 deposited on the surface. Thereby, the oxidative corrosion of the surface of the inorganic substrate 4 can be effectively suppressed.

(8) Next, the external circuit board 5 is prepared. For example, when the external circuit board 5 is an FPC, for example, a polyimide cover film is formed on the upper surface of a circuit pattern formed on the substrate by a process of forming a photoresist layer on a polyimide substrate, a DES (Development Etching Stripping) process, or the like. It can be created through a process of adhering.

  (9) Next, the wiring substrate 2 and the inorganic substrate 4 are bonded via an adhesive member. As the adhesive member, a paste-like thermosetting resin (adhesive member) is applied to either or both of the wiring substrate 2 and the inorganic substrate 4 by a screen printing method, a dispensing method, or the like. Then, in a state where the wiring substrate 2 and the inorganic substrate 4 are stacked, the bonding material is thermally cured by passing through a tunnel-type atmosphere furnace or oven, and pressurizing and heating. Is firmly bonded.

  Adhesive members include, 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, and acid anhydrides such as tetrahydromethylphthalic anhydride. It is obtained by adding carbon powder or the like as a curing agent mainly composed of, etc. and a colorant and mixing or kneading them using a centrifugal stirrer or the like to obtain a paste.

In addition, as the adhesive member, 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 Use epoxy resin such as epoxy resin, 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 do.

  (10) Next, the wiring board 2 and the external circuit board 5 are bonded via the bonding material 16. As a material of the bonding material 16, there is a material made of a resin such as an anisotropic conductive film.

  For example, when the bonding material 16 is made of an anisotropic conductive resin or the like, the bonding material 16 made of an anisotropic conductive resin is applied to a predetermined position of the external circuit board 5 or the wiring board 2 and pressed and heated. Thus, the wiring board 2 and the external circuit board 5 can be joined and electrically connected.

  Alternatively, the wiring board 2 and the external circuit board 5 may be bonded to each other by the conductive connecting material 18 and then the periphery thereof may be sealed with the bonding material 16. At this time, examples of the connecting material 18 include those made of a metal material such as solder and gold bumps, and those made of a resin such as an anisotropic conductive film.

  (11) Next, the image sensor 10 is mounted on the central region 4 b of the inorganic substrate 4. The image sensor 10 is electrically joined to the wiring board 2 by wire bonding or the like. At this time, silver epoxy or resin may be provided on the imaging element 10 or the inorganic substrate 4 and fixed to the inorganic substrate 4. Further, the lid 12 may be bonded with the bonding material 14 after the imaging device 10 is mounted on the central region 4 b of the inorganic substrate 4.

  (12) Next, the lens holder 19 is mounted on the upper surface of the wiring board 2. At this time, the electrode provided on the upper surface of the wiring board 2 and the lens holder 19 may be joined with a conductive bonding material to be electrically conductive, or the lens holder 19 may be bonded with a non-conductive bonding material. You may do it.

  The imaging device 21 is obtained by the steps (1) to (12). In addition, the process order of said (1)-(12) is not designated.

(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. Note that the imaging device 21 in this embodiment includes the imaging device mounting substrate 1, the imaging device 10, and the lens holder 19, but the lens holder 19 is omitted in FIG. The image pickup device mounting substrate 1 and the image pickup device 21 in the present embodiment are different from the image pickup device mounting substrate 1 and the image pickup device 21 in the first embodiment in that one end of the inorganic substrate 4 is a notch portion of the wiring board 2. It is a point provided at a position overlapping 2a in top view.

  In the present embodiment shown in FIG. 7, the inorganic substrate 4 has a rectangular shape, and one end overlaps the notch portion 2 a of the wiring substrate 2. Generally, by providing a thick bonding material 16 for bonding the wiring board 2 and the external circuit board 5, the possibility of the influence of the warp of the wiring board 2 or the external circuit board 5 on the bonding strength is reduced. However, if the bonding material 16 is too thick, the bonding material 16 may scoop up the notch 2a and bleed on the upper surface of the wiring board 2 in the process of bonding the wiring board 2 and the external circuit board 5. . As in the present embodiment, since one end of the inorganic substrate 4 is positioned so as to overlap with the notch portion 2a of the wiring substrate 2 in a top view, wiring is performed by the inorganic substrate 4 even if the bonding material 16 is provided thick. It is possible to reduce the bleeding of the bonding material 16 to the lower surface of the substrate 2. Therefore, it is easy to increase the thickness of the bonding material 16 and the bonding strength between the wiring board 2 and the external circuit board 5 can be further improved.

  Further, as in the example shown in FIG. 7, one end of the inorganic substrate 4 is overlapped with the cutout portion 2 a of the wiring substrate 2 in a top view, so that, for example, even if vertical vibration is applied to the external circuit substrate 5 It is possible to reduce the rotation (vibration) of the external circuit board 5 by a certain amount due to the replacement of the board 4. Therefore, the bonding area between the wiring board 2 and the external circuit board 5 is difficult to vibrate, and the bonding strength of the bonding between the wiring board 2 and the external circuit board 5 can be further improved.

(Third embodiment)
Next, an imaging element mounting substrate 1 and an imaging device 21 according to a third embodiment of the present invention will be described with reference to FIG. Note that the imaging device 21 in this embodiment includes the imaging device mounting substrate 1, the imaging device 10, and the lens holder 19, but the lens holder 19 is omitted in FIG. The difference between the imaging element mounting substrate 1 and the imaging device 21 in the present embodiment from the imaging element mounting substrate 1 and the imaging device 21 in the second embodiment is that the inorganic substrate 4 and the external circuit substrate 5 are in contact with each other. Is a point.

  In the present embodiment shown in FIG. 8, a part of the bonding material 16 is formed up to the upper surface of the external circuit board 5. In the example shown in FIG. 8, the upper surface of the inorganic substrate 4 and the lower surface of the external circuit substrate 5 are in contact with each other. Generally, when the external circuit board 5 is flexible such as FPC, its conductor is made of a very thin metal film such as a Cu film, and a wiring conductor and an electrode pad are produced. At this time, this wiring conductor or electrode When a stress that greatly vibrates or bends is applied to the pad, there is a possibility that a crack or the like may occur in the wiring conductor or the electrode pad. At this time, by providing the inorganic substrate 4 and the external circuit substrate 5 so as to be in contact with each other as in this embodiment, it is possible to reduce the application of bending stress to the wiring conductors or electrode pads of the external circuit substrate 5. It becomes possible. Therefore, it is possible to reduce the occurrence of cracks or the like in the wiring conductor or electrode pad of the external circuit board 5.

  Further, as in the example shown in FIG. 8, the inorganic substrate 4 and the external circuit substrate 5 are provided so as to be in contact with each other, and there is a space between the upper surface of the external circuit substrate 5 and the lower surface of the wiring substrate 2. It becomes possible to form fillets of the bonding material 16 at two locations on the side surface and the top surface of the external circuit board 5. Therefore, it is possible to further improve the bonding strength between the wiring board 2 and the external circuit board 5.

(Fourth embodiment)
Next, an imaging element mounting substrate 1 and an imaging apparatus 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 includes the imaging device mounting substrate 1, the imaging device 10, and the lens holder 19, but the lens holder 19 is omitted in FIG. The imaging element mounting substrate 1 and the imaging device 21 in this embodiment differ from the imaging element mounting substrate 1 and the imaging device 21 in the second embodiment between the inorganic substrate 4 and the external circuit substrate 5. The bonding material 16 is provided.

  In the present embodiment shown in FIG. 9, a part of the bonding material 16 is formed up to the lower surface of the external circuit board 5. Thus, the external circuit board 5 and the inorganic substrate 4 can be bonded using the bonding material 16. Therefore, the bonding strength between the wiring board 2 and the external circuit board 5 can be further reinforced by the bonding between the external circuit board 5 and the inorganic substrate 4. This can reduce the peeling of the wiring board 2 and the external circuit board 5.

In the present embodiment shown in FIG. 9, the bonding material 16 may be a conductive material. Thus, for example, when the inorganic substrate 4 is made of metal or has wiring conductors inside and on the surface, the external circuit substrate 5 and the inorganic substrate 4 can be electrically joined. As a result, the resistance of the power supply potential or the ground potential can be lowered using the inorganic substrate 4, and the electrical characteristics can be improved. At this time, examples of the conductive bonding material 16 include anisotropic conductive resin (ACF) and anisotropic conductive film (ACP).

(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. Note that the imaging device 21 in the present embodiment includes the imaging element mounting substrate 1, the imaging element 10, and the lens holder 19, but the lens holder 19 is omitted in FIG. The imaging device mounting substrate 1 and the imaging device 21 in the present embodiment are modifications in which the mounting configuration of the imaging device 10 of the imaging device mounting substrate 1 and the imaging device 21 in the first embodiment is changed.

  As in the example illustrated in FIG. 10, the imaging device 21 may be flip-chip mounted on the upper surface of the imaging element 10 using the wiring board 2 and gold bumps. At this time, the image pickup element 10 and the wiring board 2 are flip-chip mounted, so that the wiring board 2 can be downsized even if the image pickup element 10 is enlarged. Therefore, even if the image pickup device 10 is highly functional and the image pickup device 10 is enlarged, it is possible to reduce the weight of the wiring board 2 and to reduce the stress applied to the connection portion due to external vibration. It becomes. Therefore, it is possible to reduce the possibility that the wiring board 2 and the external circuit board 5 are peeled off.

  Further, since the image pickup element 10 and the wiring board 2 are flip-chip mounted, it is possible to increase an area where the image pickup element 10 and the wiring board 2 overlap. Therefore, the heat dissipation of the image sensor 10 can be further improved.

(Sixth embodiment)
Next, an imaging element mounting substrate 1 and an imaging device 21 according to a sixth embodiment of the present invention will be described with reference to FIG. In addition, although the imaging device 21 in this embodiment is provided with the imaging device mounting substrate 1, the imaging device 10, and the lens holder 19, the lens holder 19 is omitted in FIG. The imaging device mounting substrate 1 and the imaging device 21 in the present embodiment are different from the imaging device mounting substrate 1 and the imaging device 21 of the fifth embodiment in that there is a space between the imaging device 10 and the inorganic substrate 4. There is a point.

The imaging device 21 according to the present embodiment illustrated in FIG. 11 is provided with a distance between the imaging element 10 and the inorganic substrate 4. In general, the image sensor 10, the inorganic substrate 4, and the external circuit substrate 5 have different coefficients of thermal expansion. In general, when the image pickup apparatus 21 is used, the image sensor 10 generates heat, and the amount of generated heat increases as the function of the image sensor 10 increases. When the imaging device 10 generates heat when using the imaging device 21 mounted on the actual machine, the inorganic circuit board 4 and the external circuit board 5 to which the lower surface of the inorganic circuit board 4 is connected are also heated by the heat. At this time, the deformation stress is applied to the distorted portion due to the difference in coefficient of thermal expansion. At this time, the stress is also transmitted to the bonding region between the wiring board 2 and the external circuit board 5, and the possibility of peeling occurs. Further, if vibration stress is applied to the external circuit board 5 in this state, the possibility of peeling becomes higher. By providing a distance between the image sensor 10 and the inorganic substrate 4 as in the present embodiment, the heat of the image sensor 10 is hardly transmitted to the inorganic substrate 4. Therefore, it becomes possible to reduce the deformation stress due to the difference in thermal expansion coefficient between the image pickup element 10, the inorganic substrate 4, and the external circuit substrate 5. Therefore, even when vibration is applied to the external circuit board 5 when the imaging device 21 is used, it is possible to reduce the possibility that the wiring board 2 and the external circuit board 5 are peeled off.

(Seventh embodiment)
Next, an imaging element mounting substrate 1 and an imaging device 21 according to a seventh embodiment of the present invention will be described with reference to FIG. Note that the imaging device 21 in this embodiment includes the imaging device mounting substrate 1, the imaging device 10, and the lens holder 19, but FIG.
Omits the lens holder 19. The image pickup device mounting substrate 1 and the image pickup device 21 in the present embodiment are different from the image pickup device mounting substrate 1 and the image pickup device 21 of the fifth embodiment in that the central region 4b of the inorganic substrate 4 is a space. The point is that a notch 2a is formed by the wiring substrate 2 and the inorganic substrate 4 (having holes).

  In the imaging device 21 of the present embodiment shown in FIG. 12, the central region 4b of the inorganic substrate 4 is a space, and the imaging element 10 is housed in the space. As a result, the imaging element 10 can be provided at the position where the inorganic substrate 4 is provided, so that the imaging device 21 can be reduced in size and weight. Therefore, the weight of the imaging device 21 can be reduced, and the stress applied to the connection region due to external vibration can be reduced. Therefore, it is possible to reduce the possibility that the wiring board 2 and the external circuit board 5 are peeled off.

  In the imaging device of this embodiment shown in FIG. 12, a notch 2 a is formed by the lower surface of the wiring substrate 2 and the side surface of the inorganic substrate 4. As a result, the image pickup device 21 can be further reduced in size and weight.

  At this time, the wiring substrate 2 and the inorganic substrate 4 may be made of the same material or may be electrically connected. Since the wiring substrate 2 and the inorganic substrate 4 are made of the same material, it is possible to reduce deformation and stress on the joint due to a difference in coexistence of aspirations in the process of heating and mounting the imaging element 10 or the inorganic substrate 5.

  In addition, this invention is not limited to the example of the above-mentioned embodiment, Various modifications, such as a numerical value, are possible. For example, in the example shown in FIGS. 1 to 12, the shape of the image sensor connection pad 3 is a rectangular shape, but it may be a circular shape or other polygonal shapes. In addition, the arrangement, number, shape, and the like of the image sensor connection pad 3 in the present embodiment are not specified. In addition, the various combinations of the characteristic part in this embodiment are not limited to the example of the above-mentioned embodiment.

DESCRIPTION OF SYMBOLS 1 ... Image sensor mounting substrate 2 ... Wiring substrate 2a ... Notch 3 ... Image sensor connection pad 4 ... Inorganic substrate 4a ... Peripheral region 4b ... -Central region 5 ... External circuit board 10 ... Imaging element 12 ... Lid 13 ... Connection member 14 ... Joining member 16 ... Joining material 18 ... Connecting material 19 ...・ Lens holder 21 ... Imaging device

Claims (6)

An image sensor mounting portion on which an image sensor is mounted on an upper surface; an inorganic substrate having a peripheral region surrounding the image sensor mounting portion;
A wiring board provided on the peripheral region of the inorganic substrate, surrounding the imaging element mounting portion, and having a frame shape with an outer edge larger than the inorganic substrate and notched from a side surface to a lower surface; ,
A sheet-like external circuit board connected to the notch of the wiring board,
The imaging device mounting board, wherein the external circuit board is connected to the wiring board through a bonding material formed from a side surface to an upper surface. The imaging device mounting substrate according to claim 1,
The substrate for mounting an image pickup device, wherein the inorganic substrate has a rectangular shape, and one end thereof overlaps a notch portion of the wiring substrate. The imaging device mounting substrate according to claim 2,
Part of the bonding material is formed up to the upper surface of the external circuit board. The imaging device mounting substrate according to claim 3,
A part of the bonding material is formed up to the lower surface of the external circuit board. The imaging device mounting substrate according to claim 2,
An imaging element mounting substrate, wherein an upper surface of the inorganic substrate and a lower surface of the external circuit substrate are in contact with each other. The imaging device mounting substrate according to any one of claims 1 to 5,
An imaging apparatus comprising: an imaging element mounted on the imaging element mounting portion of the inorganic substrate of the imaging element mounting substrate; and a lens holder fixed to the lens mounting portion of the wiring board.

Images