JP2011154305A - Imaging apparatus and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact imaging apparatus 1 in which distances between a CCD 41 and lens substrate parts 11 and 13 can be varied. <P>SOLUTION: The imaging apparatus 1 includes a fixed part 3 and a movable part 2, wherein the fixed part 3 includes a CCD substrate part 40 having the CCD 41, a piezoelectric element substrate part 30 comprising a piezoelectric substrate part 31 having electrode films 32 and 33 on both sides, and a shaft 20 erected on the piezoelectric element substrate part 30 and transmitting vibration. The movable part 2 is a lens unit part capable of moving in a longitudinal direction of the shaft 20, and the movable part 2 made an individual piece from a movable part substrate 2A is fit to the shaft 20 of a fixed substrate part 50 made an individual piece from a fixed part substrate 50A. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image pickup apparatus using a wafer level chip size package technique and a method for manufacturing the image pickup apparatus.

  Electronic endoscopes, camera-equipped mobile phones, digital cameras, and the like equipped with an imaging device having a solid-state imaging device such as a CCD are widely used. The imaging apparatus includes a main part including a solid-state imaging device and an imaging optical system having a lens that guides an optical image of a subject to the solid-state imaging device.

  A manufacturing method using a wafer level chip size package (WCSP) method is known for downsizing and mass-producing an imaging apparatus. For example, Japanese Patent Application Laid-Open No. 2003-204053 discloses a method for obtaining an imaging device by cutting a semiconductor wafer having a CCD and a substrate having a lens or the like into pieces after bonding.

  On the other hand, Japanese Translation of PCT International Publication No. 2007-516688 discloses a small ultrasonic linear motor in which a moving body mounted on a moving shaft attached to a piezoelectric substrate moves linearly.

However, since the imaging device manufactured using the WCSP method is a fixed focus type in which the distance between the imaging element and the lens is fixed, focusing and zooming cannot be performed.
Moreover, since it is necessary to assemble the small ultrasonic linear motors one by one, further miniaturization and mass production have not been easy.

JP 2003-204053 A Special table 2007-516688 gazette

  An object of the present invention is to provide a small-sized imaging device in which a distance between an imaging element and a lens is variable, and a method for manufacturing the imaging device.

  In order to achieve the above object, an image pickup apparatus according to an embodiment of the present invention is an image pickup apparatus including a fixed portion and a movable portion, and the fixed portion includes an image pickup element substrate portion having an image pickup element, and the image pickup device. A piezoelectric element substrate portion that is bonded to the element substrate portion and has electrode films on both sides and vibrates in the direction of the film surface, and is erected on the piezoelectric element substrate portion, and vibrations of the piezoelectric element substrate portion are A shaft for transmitting, the movable part is a lens unit part movable in a longitudinal direction of the shaft, the imaging element substrate in which the imaging elements are arranged in a lattice shape, and the piezoelectric element substrate part A plurality of lens substrate parts arranged in a lattice form on the shaft of the fixed part separated from a fixed part substrate joined to the piezoelectric element substrate arranged in the lattice form; The spacer substrate part of the lattice And placed spacer substrate, the movable portion which is sectioned from the movable unit substrate bonded is, characterized in that fitted.

  An imaging device manufacturing method according to another embodiment of the present invention is a manufacturing method of an imaging device including a fixed portion and a movable portion, and an imaging element substrate portion having an imaging element is arranged in a grid pattern. The imaging element substrate creating step for creating the image sensing element substrate, the piezoelectric element substrate creating step for creating the piezoelectric element substrate having electrode films on both sides of the piezoelectric substrate, and the piezoelectric element substrate are arranged in the lattice shape. Piezoelectric element patterning step patterned on a plurality of piezoelectric element substrate portions, the imaging element substrate and the patterned piezoelectric element substrate joined together, and the imaging element substrate / piezoelectric element substrate joining step and the imaging element A fixed part substrate having a substrate part and the piezoelectric element is cut and separated into individual fixed substrate parts, and a shaft is erected on the piezoelectric element substrate part. A lens in which a shaft setup process in which a fixing portion is created, a lens substrate in which a plurality of lens substrate portions are arranged in a lattice shape, and a spacer substrate in which a plurality of spacer substrate portions are arranged in the lattice shape are joined A movable part singulation process for cutting the unit substrate into individual movable parts, and an assembly process in which the shaft of the fixed part and the movable part are fitted to each other. To do.

  ADVANTAGE OF THE INVENTION According to this invention, the small imaging device with which the distance between an image pick-up element and a lens is variable, and the manufacturing method of the said imaging device can be provided.

1 is an external view of an imaging apparatus according to a first embodiment. It is an exploded view of the imaging device of a 1st embodiment. It is an exploded view for demonstrating the cross-sectional structure of the imaging device of 1st Embodiment. It is explanatory drawing for demonstrating the manufacturing method of the movable part of the imaging device of 1st Embodiment. It is explanatory drawing which showed the cross-sectional structure for demonstrating the manufacturing method of the fixing | fixed part of the imaging device of 1st Embodiment. It is explanatory drawing which showed the cross-sectional structure for demonstrating the manufacturing method of the fixing | fixed part of the imaging device of 1st Embodiment. It is explanatory drawing which showed the cross-sectional structure for demonstrating the standing-up method of the shaft of the fixing | fixed part of the imaging device of 1st Embodiment. It is explanatory drawing which showed the cross-sectional structure for demonstrating the standing-up method of the shaft of the fixing | fixed part of the imaging device of 1st Embodiment. It is explanatory drawing for demonstrating the cross-section of the imaging device of 2nd Embodiment. It is explanatory drawing for demonstrating the cross-section of the imaging device of 3rd Embodiment. It is an exploded view of the imaging device of 4th Embodiment. It is explanatory drawing for demonstrating the cross-section of the imaging device of 5th Embodiment.

<First Embodiment>
Hereinafter, the imaging apparatus 1 according to the first embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1, 2, and 3, the imaging device 1 includes a fixed portion 3 and a movable portion 2 that fits with the shafts 20 and 21 of the fixed portion 3 and can move in the optical axis O direction. To do. As will be described later, the CCD substrate portion 40 of the movable portion 2 and the fixed portion 3 is manufactured by separating a bonded substrate in which a plurality of substrates are bonded by the WCSP method. When the substrate is cut by blade dicing, it becomes a quadrangular columnar shape. However, when laser dicing or the like is used, it can be formed into a polygonal columnar shape or a cylindrical shape. Each figure is a schematic diagram for explanation, and the scale in the thickness direction differs depending on the constituent elements. For example, a thickly illustrated substrate portion is not necessarily thicker than a thinly illustrated substrate portion. Further, hereinafter, the upper surface (front surface) of the substrate means the surface on the subject side, and the lower surface (back surface) means the surface opposite to the subject.

  The fixing unit 3 is connected to the CCD substrate unit 40 that is an imaging element substrate unit, the piezoelectric element substrate unit 30, the shaft 20 that is a drive shaft that is erected on the piezoelectric element substrate unit 30 and transmits vibrations, and the CCD substrate unit 40. And a shaft 21 that is a standing guide shaft.

  The CCD substrate unit 40 is made of, for example, a single crystal silicon substrate, and a CCD 41 that is an image pickup element is formed in the approximate center of the upper surface using a semiconductor circuit creation technique. A CMOS or the like may be used as the image sensor. The CCD substrate 40 is formed with a through wiring 41T for power supply and signal transmission of the CCD 41 through an insulating film (not shown), and an electrode 42 connected to the through wiring 41T on the lower surface.

  The piezoelectric element substrate portion 30 bonded to one of the four corners of the CCD substrate portion 40 is a so-called thickness vibrator having electrode films 32 and 33 on both surfaces of the piezoelectric substrate portion 31 and vibrating in the film surface direction. . That is, the piezoelectric substrate portion 31 is made of a piezoelectric material that is deformed by application of an electric field.

  The piezoelectric substrate unit 31 is an ultrasonic transducer that repeatedly vibrates and contracts between the electrode film 32 and the electrode film 33 when the voltage applied to the electrode films 32 and 33 changes. Note that a multilayer piezoelectric element in which a plurality of piezoelectric materials are stacked via a plurality of electrode films may be used as the piezoelectric element substrate portion 30. The wiring 32S is a side wiring that connects the electrode film 32 on the top surface and the electrode 44 on the back surface. On the other hand, the electrode film 33 is connected to the electrode 43 on the back surface through the through wiring 33T.

  The electrode film 32 is preferably thicker than the one electrode film 33. Since the electrode film 33 only needs to have an energization function for applying a voltage to the piezoelectric element substrate portion 30, it may be, for example, less than 1 μm. On the other hand, the electrode film 32 is provided with a function as an elastic body in addition to the energization function.

  The shaft 20 is a substantially cylindrical drive shaft made up of, for example, metal standing on the electrode film 32, and the shaft 20 is relatively hard and fits with the through hole 2 </ b> H <b> 1 of the movable portion 2. That is, the vibration of the piezoelectric element substrate portion 30 is transmitted to the shaft 20 through the electrode film 32. On the other hand, the shaft 21 is a substantially cylindrical guide shaft, for example, made of metal, which is also erected on the CCD substrate 40. That is, the shaft 21 is relatively loosely fitted with the through hole 2H2 of the movable portion 2, and the shaft 21 does not hinder the vertical movement of the movable portion 2.

  1 and the like illustrate the case where the outer diameter r2 of the shaft 21 is smaller than the outer diameter r1 of the shaft 20 and the through hole 2H1 and the through hole 2H2 have the same inner diameter R1, but the outer diameter of the shaft 21 is illustrated. The outer diameter of the shaft 20 may be the same, and the inner diameter of the through hole 2H2 may be larger than the inner diameter of the through hole 2H1. The shaft 20 may be, for example, a polygonal column shape such as a quadrangular column shape. In this case, the shaft 20 is a guide shaft for fixing the relative position in the in-plane direction of the movable unit 2 and the fixed unit 3. A certain shaft 21 is not necessarily arranged. That is, the imaging device 1 has at least one drive shaft.

  On the contrary, an imaging device in which guide shafts are erected at three locations at four corners, and a fixed portion having three guide shafts and one drive shaft and a movable portion having four through holes are fitted. It may be. Moreover, you may use the shaft from which a shape differs in one imaging device.

  On the other hand, the lens unit portion which is the movable portion 2 includes a plurality of lens substrate portions 11 and 13 and spacer substrate portions 12 and 14 having a hollow optical path region for determining the distance between the lens substrate portions 11 and 13 in the optical axis direction. And having. The lens substrate portions 11 and 13 have lens portions 11L and 13L constituting an optical system at substantially the center, respectively. And the through-holes 2H1 and 2H2 are formed in two places of four corners, respectively.

  As already described, since the movable part 2 is formed by the WCSP method, the shape when viewed from above is rectangular, but the four corners are useless parts that are not used optically. By forming the through holes 2H1 and 2H2 at the four corners which are optically useless parts in the imaging apparatus 1, the movable portion 2 can move in the longitudinal direction of the shafts 20 and 21 without increasing the external dimensions of the imaging apparatus 1. It is. Similarly, in the fixed portion 3, since the piezoelectric element substrate portion 30 and the shafts 20 and 21 are disposed at the four corners that are useless portions, the external dimensions of the imaging device 1 can be increased. Absent.

  Although not shown, the friction coefficient of the fitting surface may be increased by roughening at least one of the outer surface of the shaft 20 and the inner surface of the through hole 2H1 by a sandblasting method or an etching method. An imaging device having a reasonably high friction coefficient on the fitting surface has good drive characteristics of a movable part that moves by inertial force, as will be described later.

  Next, a method for driving the movable portion 2 of the imaging apparatus 1 will be briefly described. In the imaging apparatus 1, the principle of movement of the movable portion 2 is the same as that of the known small ultrasonic linear motor already described, and utilizes inertial force. That is, the piezoelectric element substrate portion 30, the shaft 20, and the movable portion 2 constitute an ultrasonic linear actuator. For this reason, the movable part 2 can move up and down (front and rear) in the longitudinal direction of the shaft 20 based on a voltage signal from a power source (not shown).

  That is, by adjusting the deformation speed of the piezoelectric element substrate section 30, in other words, the moving speed of the shaft 20 of the fixed section 3, the movable section 2 moves in the upward direction, that is, the subject direction, or in the downward direction, that is, in the CCD 41 direction. Or move to. For example, when the thickness of the piezoelectric element substrate portion 30 is deformed by ΔL at a predetermined speed, the movable portion 2 fitted to the shaft 20 also moves ΔL upward. However, instantaneously, in other words, when the piezoelectric element substrate portion 30 contracts and deforms to the original thickness at an extremely high speed, the movable portion 2 having a weight cannot follow the moving speed of the shaft 20 due to the law of inertia. For this reason, the movable part 2 stays at a position of ΔL in the upward direction at a relative position to the fixed part 3. When the piezoelectric element substrate portion 30 is again deformed by ΔL at a predetermined speed, the movable portion 2 fitted to the shaft 20 further moves ΔL upward. When the piezoelectric element substrate portion 30 shrinks and deforms to the original thickness again at a high speed, the movable portion 2 stays at a position ΔL in the upward direction relative to the fixed portion 3. By repeating the above operation, the movable portion 2 moves upward. Similarly, after the piezoelectric element substrate section 30 is contracted and deformed at a predetermined speed, and then is deformed to an original thickness at a high speed, the movable section 2 moves downward.

  The deformation speed of the piezoelectric element substrate section 30 (the movement speed of the shaft 20 of the fixed section 3) can be controlled by the change pattern of the voltage applied to the electrode films 32 and 33. For example, a drive voltage signal having a sawtooth pattern is used. Thus, deformation at a predetermined speed and high-speed deformation can be repeated.

  Since the through hole 2H1 of the movable portion 2 and the shaft 20 are relatively tightly fitted, the movable portion 2 is fixed to the shaft 20 when the piezoelectric element substrate portion 30 is not driven. The relative position of the movable part 2 and the fixed part 3 does not change.

  Next, a method for manufacturing the imaging device of the present embodiment will be described with reference to FIGS. In the manufacturing method of the imaging device 1, after the movable part 2 and the fixed part 3 are manufactured by the WCSP method, the through hole 2H1 of the movable part 2 is fitted to the shaft 20 of the fixed part 3 in the assembly process.

  Initially, the manufacturing method of the movable part 2 is demonstrated. As shown in FIG. 4, the lens unit unit that is the movable unit 2 is configured to move the movable unit substrate 2A that is a lens unit substrate in which a plurality of lens substrates 11A and 13A and a plurality of spacer substrates 12A and 14A are joined. By cutting along the cutting line L in the partial singulation process, the individual singulation is performed. The lens substrate 11A has a plurality of lens substrate portions 11 arranged in a lattice pattern. Similarly, in the lens substrate 13 </ b> A, a plurality of lens substrate parts 13 are arranged in the same lattice shape as the lens substrate part 11. In the spacer substrates 12A and 14A, a plurality of spacer substrate portions 12 and 14 are arranged in the same grid as the lens substrate portion 11.

  The lattice shape is not limited to a state in which the grid is arranged at a predetermined interval in the vertical and horizontal directions, but may be a state in which the grid is arranged at a predetermined interval in an oblique direction.

  As shown in the spacer substrate 14A in FIG. 4, the outer peripheral portion of each substrate is not shown. FIG. 4 shows an example in which the components are arranged in a 10 × 10 grid on each substrate. However, for mass productivity, the components are arranged in a grid of 20 × 20 or more. It is preferable.

  The lens substrates 11A and 13A are formed by, for example, pouring a material between two molds or press-molding a flat plate. As a material of the lens substrates 11A and 13A, glass, polycarbonate, polyester, acrylic, or the like can be used as long as it is a transparent material. Moreover, it is not limited to a single material, and may be a composite member of resin and glass, for example. Furthermore, it is not necessary that all be made of a transparent material, and at least a portion corresponding to the optical path of the imaging optical system is made of a transparent material.

  The spacer substrates 12A and 14A may be made of the same glass as the lens substrate 11A or the like, or a transparent resin material, but need not be transparent, ABS resin, epoxy resin, phenol resin, metal, silicon, ceramic material You may make from etc.

  Note that an imaging device in which the lens frame portions of the lens substrates 11A and 13A and the peripheral portions of the spacer substrates 12A and 14A are made of a light shielding material is not easily affected by ambient light.

  In the bonding step, the lens substrates 11A and 13A are bonded via the spacer substrates 12A and 14A, thereby creating the movable part substrate 2A. In the joining process, an adhesive is applied to the joining surfaces. Various known adhesives can be used as the adhesive. Note that the adhesive need not be applied to the entire joining surface to be joined, and may be applied only to a predetermined region by a known method, for example, an inkjet method.

  The substrates to which the adhesive has been applied are joined together by curing the adhesive while being pressed in a state of being overlaid. Note that it is not necessary to bond all the substrates at the same time, and it is not necessary to bond them from the lower or upper substrate. Moreover, the resin substrate made into the high temperature state may be joined without using an adhesive, or may be joined by anodic bonding.

  Further, if necessary, the flatness of the bonded substrate as a whole is adjusted after the adhesive is cured. The other bonding steps described below are the same as described above.

  And the through-holes 2H1 and 2H2 are formed in the four corners of each movable part 2, ie, the outer peripheral part of an optical system, of the movable part substrate 2A. The through hole can be formed by etching, machining using a mechanical drill, laser machining, or the like. Or you may form the through-hole in each board | substrate before joining. In addition, when roughening the inner surface of a through-hole, it is preferable to carry out before the singulation process from a viewpoint of mass productivity.

  In the above description, the case where the lens unit portion includes two lens substrate portions and two spacer substrate portions has been described. However, in an imaging device that requires higher optical characteristics, a lens unit unit in which a larger number of lens substrate units are joined via a spacer substrate unit may be used. Furthermore, a lens unit portion to which a cover substrate portion made of a flat transparent material is bonded may be used.

  Then, in the individualization step, the movable part substrate 2A is cut along the cutting line L, so that it is separated into individual movable parts 2 (lens unit parts). In the individualization step, the movable part substrate 2A is cut and separated into pieces while being fixed by a fixing substrate or the like (not shown). For the cutting, a wire saw, a blade dicing apparatus, a laser dicing apparatus, or the like can be used. Then, a separation step of separating the individual lens unit portions from the fixing substrate or the like after the cutting is performed. Even after cutting, at the stage before the separation step, the movable part 2 is separated into individual pieces, but the state of being arranged in a lattice shape is maintained. For this reason, as will be described later, it is possible to perform processing in batches in units of substrates. The other singulation steps described below are the same as described above.

  Next, the manufacturing method of the fixing | fixed part 3 is demonstrated. The fixed portion 3 is a fixed portion substrate in which a CCD substrate 40A, which is an image pickup device substrate in which a plurality of CCDs 41 are arranged in a lattice shape, and a piezoelectric element substrate 30A in which a plurality of piezoelectric element substrate portions 30 are arranged in a lattice shape are joined. Further, in the shaft setup process, the shaft 20 is formed on the piezoelectric element substrate 30A, and the shaft 21 is provided on the CCD substrate 40A in a standing manner, that is, vertically. When the movable unit 2 and the fixed unit 3 are not assembled in units of substrates, the lattice arrangement of the movable substrate 2A and the lattice arrangement of the fixed substrate 50A may be different.

As shown in FIG. 5A, in the piezoelectric element substrate forming step, the electrode film 32A and the electrode film 33A are formed on both surfaces of the piezoelectric substrate 31A made of a piezoelectric material by sputtering or plating, and the piezoelectric element substrate 30A. Is created. Examples of the piezoelectric material include quartz, lithium niobate (LN), potassium dihydrogen phosphate (KDP), ammonium dihydrogen phosphate (ADP), lithium sulfate, Rochelle salt, zinc oxide, or polyvinylidene fluoride of an organic piezoelectric material ( In addition to PVDF, etc., lead zirconate titanate (PZT) having an electrostrictive effect can also be used. That is, the piezoelectric material and the electrostrictive material are materials having strictly different effects, but in the description of the present invention, they are treated as the same because they have the same effect.
A thin film material obtained by sputtering or the like can be used as the piezoelectric material, but a sintered material is preferably used in order to obtain high characteristics.

  In addition, since the electrode film 32A is formed thicker than the one electrode film 33A, it is preferable to use an electrolytic copper plating method that facilitates thick film formation. That is, the electrode film 32A is a conductive metal film such as copper, but has a film thickness of 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more. If it is more than the said range, it will be easy to transmit a vibration to the shaft 20. FIG. The upper limit of the film thickness of the electrode film 32A is not particularly limited, but is, for example, about 1 mm due to manufacturing restrictions. The electrode film 32A need not be a single-layer metal film, and different types of materials may be laminated. Furthermore, the electrode film 32A may be a composite film in which a non-conductive elastic film made of resin or the like is laminated on a conductive film, and the shaft 20 may be erected thereon.

  Next, in the piezoelectric element substrate / holding substrate bonding step shown in FIG. 5B, the electrode film 32A side of the piezoelectric substrate 31A is bonded to the holding substrate 39A. The holding substrate 39A is a fixing film or the like for temporarily fixing the piezoelectric element substrate 30A, and is a substrate that can be easily peeled later by UV irradiation or thermal foaming treatment.

Next, as shown in FIGS. 5C, 5D, and 5E, in the piezoelectric element patterning step, the piezoelectric substrate 31A and the electrode films 32A, 33A excluding the region masked by the mask layer 38A. Are removed by etching or the like, and patterned into a plurality of piezoelectric element substrate portions 30 arranged in a lattice pattern.
The shape of the piezoelectric element substrate portion 30 is not limited to a rectangle, and may be any shape such as a circle, an ellipse, or a polygon.

On the other hand, as shown in FIG. 6A, in the imaging element substrate creation step, a CCD substrate 40A, which is an imaging element substrate in which a plurality of CCD substrate portions 40 having CCDs 41 are arranged in a grid, is created. By using a silicon substrate as the CCD substrate 40A, the CCD 41 can be formed inside using a semiconductor fabrication technique. Note that the CCD substrate 40A is polished from the back side to facilitate the formation of the through wiring 41T and the like, and the total thickness is processed to 100 μm or less, for example. A conductor is formed inside a through hole formed by a known etching method or the like, and through wirings 41T and 33T are created. Further, electrodes 42 and 43 that are electrically connected to the through wirings 41T and 33T are formed on the back surface side. The electrodes 42 and 43 are connection bumps when the imaging device 1 is mounted on another substrate, but may be formed in a later step. In the following drawings, the electrodes 42 and 43 may not be displayed.
Further, the connection terminal for connecting the electrode film 32 to a power source (not shown) is not necessarily formed on the back surface side, and may be formed on the front surface side or the side surface as appropriate depending on the mounting method.

  Then, as shown in FIG. 6B, an imaging element substrate / piezoelectric element substrate bonding step in which the CCD substrate 40A and the piezoelectric element substrate 30A are bonded is performed. At this time, the electrode film 33 is connected to the through wiring 33T. In the holding substrate separating step, the holding substrate 39A is separated from the fixed portion substrate 50A including the piezoelectric element substrate 30A.

  On the other hand, as shown in FIG. 7A, a setup board 29A for separately setting up a large number of shafts is prepared. In the setup board 29A, a large number of holes 20A into which the shaft 20 can be inserted and a large number of holes 21A into which the shaft 21 can be inserted are formed in a predetermined lattice shape at predetermined positions. Small holes 28 for vacuum suction are provided at the bottoms of the holes 20A and 21A.

  The diameter of the hole 20A is larger than the diameter of the hole 21A. For this reason, when the setup board 29A is swung / vibrated with a so-called transfer (vibration setup) device with a large number of shafts 20 mounted on the setup board 29A, as shown in FIG. 20 are collectively inserted into the respective holes 20A. Next, when the setup board 29A is swung / vibrated in a state where a large number of shafts 21 are placed on the setup board 29A, as shown in FIG. Inserted into.

Then, as shown in FIG. 8A, the plurality of shafts 20 fixed to the setup substrate 29A while sucking from the small holes 28 are integrated into the piezoelectric element substrate unit 30, and the plurality of shafts 21 are integrated into the CCD substrate unit 40. The shaft setup process for joining is performed. As shown in FIG. 8B, after the bonding, the fixed substrate 3A in which a plurality of fixed portions 3 are arranged in a lattice shape is created by removing the setup substrate 29A.
In FIG. 8A, the shaft 20 fixed to the setup board 29A is shown on the upper side, but the fixed part board 50A may be joined on the upper side.

  8A and 8B, a holding substrate for temporarily fixing a fixed portion substrate 50A having the CCD substrate portion 40 and the piezoelectric element substrate portion 30 before the shafts 20 and 21 are joined. The case where it processes by a board | substrate unit in the state which cut | disconnects and does not isolate | separate after joining to 49A is illustrated. That is, FIG. 8A shows the fixed substrate portion 50 separated into pieces by the cutting margins L1 and L2 cut along the cutting line. Of course, you may cut | disconnect after a shaft setup.

  In the assembly process, the shafts 20 and 21 of the fixed portion 3 and the through holes 2H1 and 2H2 of the movable portion 2 are fitted. At this time, in order to obtain a desired drive characteristic, it is necessary to fit the shaft 20 and the through hole 2H1 in a moderately hard manner. For this reason, it is preferable that the material forming the through hole 2H1 and the material of the shaft 20 are made of materials having different thermal expansion coefficients. For example, the material for forming the through-hole 2H1, that is, the lens substrate portions 11 and 13 and the spacer substrate portions 12 and 14 are made of a material having a low thermal expansion coefficient such as glass, and the shaft 20 is a metal having a high thermal expansion coefficient, for example, SUS. It consists of. For example, the thermal expansion coefficient α of glass is 3.2 ppm / degree and the thermal expansion coefficient α of SUS is 17.3 ppm / degree. For this reason, even if the shaft 20 has a predetermined outer diameter and the through hole 2H1 has an outer diameter that is substantially the same as the outer diameter of the shaft 20 at room temperature, the shaft 20 can be easily inserted into the through hole 2H1 by performing an assembly process while cooling. Can be inserted in. And when it becomes normal temperature after an assembly, the shaft 20 fits hard with the through-hole 2H1.

  Alternatively, the material forming the through hole 2H1 may be made of a resin having a thermal expansion coefficient larger than that of the material of the shaft 20, for example, SUS, and the assembly process may be performed while heating.

  In the imaging apparatus 1, the material forming the through hole and the material of the shaft have different coefficients of thermal expansion and are fitted while being heated or cooled in the assembly process. It is easy to obtain strength. The difference in coefficient of thermal expansion between the material for forming the through hole and the material for the shaft is appropriately selected according to the desired fitting strength, shaft diameter, etc., but is preferably 5 ppm / degree to 100 ppm / degree, Especially preferably, it is 10 ppm / degree or more and 75 ppm / degree or less. If it is more than the said range, an assembly is easy, and if it is less than the said range, the influence of the drive characteristic change by use temperature is small.

  In the assembly process, the movable parts 2 that have been cut / separated may be fitted one by one to the single fixed part 3 that has been cut / separated, but as shown in FIG. From the viewpoint of improving productivity, it is preferable to fit one movable portion 2 that has been cut to the fixed portion 3 that has been cut and held on the holding substrate 49A and arranged in a lattice shape, in terms of productivity.

  In addition, the wiring 32S is formed in the fixing part 3 after the assembly process or after being singulated using a conductive paste or the like.

  As described above, after the movable part 2 and the fixed part 3 are manufactured by the WCSP method, the imaging device 1 in which the movable part 2 is fitted to the fixed part in the assembly process can be mass-produced in large quantities. Yes, high yield and low cost can be realized.

  In the imaging apparatus 1, since the distance between the CCD 41 of the fixed unit 3 and the lens unit 11 </ b> L of the lens unit unit can be controlled by controlling the movement of the movable unit 2, focusing can be performed.

  As described above, the imaging device 1 is a small imaging device manufactured using the WCSP method, but can perform focusing. In other words, the imaging device manufacturing method of the present embodiment can mass-produce small imaging devices that can perform focusing, and can achieve high yield and low cost. Since the imaging device 1 is a small imaging device, it can be preferably used for an endoscope, particularly a capsule endoscope, or a camera-equipped mobile phone.

<Second Embodiment>
Next, the imaging device 1B and the manufacturing method of the imaging device 1B according to the second embodiment of the present invention will be described. Since the imaging device 1B and the manufacturing method of the imaging device 1B according to the present embodiment are similar to the imaging device 1 and the manufacturing method of the imaging device 1 according to the first embodiment, the same components are denoted by the same reference numerals, Description is omitted.

  The imaging device 1B has substantially the same appearance as the imaging device 1 shown in FIG. 1 and the like, but as shown in FIG. 9, the fixing portion 3B has two piezoelectric element substrate portions 30 and 30B, and the shaft 20B It fits tightly with the through hole 2H3 of the movable part 2B. That is, the fixed portion 3B has two piezoelectric element substrate portions 30, 30B and two shafts 20, 20B, and the movable portion 2B is fitted to each of the two shafts 20, 20B. There are two through holes 2H1 and 2H3.

  In the fixing portion 3B, the electrode film 32 on the upper surface of the piezoelectric element substrate portion 30 is connected to the electrode 45 on the back surface through the through wiring 32T. The piezoelectric element substrate portion 30B includes the piezoelectric substrate portion 31B and electrode films 32B and 33B connected to the electrodes 43B and 45B via the through wirings 32TB and 33TB on both surfaces of the piezoelectric substrate portion 31B.

  The imaging device 1B has the same effect as the imaging device 1, and can further improve the drive characteristics of the movable portion 2B than the imaging device 1 by driving the two drive shafts in synchronization. Moreover, since there is no side wiring, the manufacturing process after separation is simple.

<Third Embodiment>
Next, an imaging device 1C and a manufacturing method of the imaging device 1C according to the third embodiment of the present invention will be described. Since the imaging device 1C and the manufacturing method of the imaging device 1C according to the present embodiment are similar to the imaging device 1 and the manufacturing method of the imaging device 1 according to the first embodiment, the same components are denoted by the same reference numerals, Description is omitted.

  As shown in FIG. 10, the movable portion 2C of the imaging device 1C includes a fitting substrate portion 15 having a through hole 15H for fitting with the shaft 20 of the fixed portion 3C. And the internal diameter of the through-hole 2H1 formed in the lens board | substrate parts 11 and 13 and the spacer board | substrate parts 12 and 14 is larger than the through-hole 15H.

  As a material for the mating substrate portion 15, for example, a metal or ceramic having excellent wear resistance is used. That is, unlike the lens substrate portion or the spacer substrate portion constituting the optical system of the lens unit portion, the fitting substrate portion 15 can be selected from materials suitable for fitting since there is no material selection restriction.

  The image pickup apparatus 1C has the same effect as the image pickup apparatus 1. Further, since only the fitting substrate portion 15 among the members constituting the movable portion 2 is fitted to the drive shaft, the fitting strength is adjusted. For example, when the mating substrate portion 15 is made of a material having excellent wear resistance, the driving characteristics are not changed even during long-term use.

In the imaging device 1 and the like according to the first embodiment, it is not necessary to be tightly fitted to the shaft 20 at all locations on the inner wall of the through hole 2H1, but at least one substrate portion, for example, Only the lens substrate portion 11 may be fitted tightly with the shaft 20, and the other lens substrate portion 13 and the spacer substrate portions 12 and 14 may be loosely fitted with the shaft 20.
Moreover, you may provide the function of the board | substrate part for a fitting to a spacer board | substrate part. Further, the plurality of substrate portions of the movable portion may have the function of the mating substrate portion.

  As shown in FIG. 10, in the imaging apparatus 1 </ b> C, a shaft 21 that is a guide shaft also stands on a piezoelectric element substrate portion 30 </ b> B that is the same as the shaft 20 that is a drive shaft. For this reason, the shaft 20 and the shaft 21 have the same length. Further, the shaft 20 and the shaft 21 have the same outer diameter. For this reason, the shaft insertion process to the setup board | substrate of a shaft setup process is sufficient once. Since the piezoelectric element substrate portion 30B is provided for adjusting the length of the shaft, wiring for driving is not connected.

<Fourth embodiment>
Next, an imaging device 1D and a manufacturing method of the imaging device 1D according to the fourth embodiment of the present invention will be described. Since the imaging device 1D and the manufacturing method of the imaging device 1D of the present embodiment are similar to the imaging device 1 and the manufacturing method of the imaging device 1 of the first embodiment, the same components are denoted by the same reference numerals, Description is omitted.

  As illustrated in FIG. 11, the imaging device 1D includes a plurality of movable parts 4 and 5 that are independently movable in the optical axis O direction. That is, each of the movable parts 4 and 5 has through holes 2H1 and 2H4 that are fitted to the shafts 20 and 20B, respectively. The movable portion 4 is a first lens unit portion having lens substrate portions 11D, 13D, and 15D and spacer substrate portions 12D and 13D, and the movable portion 5 is a first lens unit portion having lens substrate portions 11 and 13 and spacer substrate portions 12 and 13. 2 is a lens unit portion.

  The through hole 2H5 of the movable part 4 has an inner diameter that fits loosely with the shaft 20 of the fixed part 3D, and the through hole 2H4 has an inner diameter that fits tightly with the shaft 20B. On the other hand, the through hole 2H1 of the movable portion 5 has an inner diameter that fits tightly with the shaft 20, and the through hole 2H6 has an inner diameter that fits loosely with the shaft 20B. That is, the shaft 20 has a function as a drive shaft for the movable part 5 and functions as a guide shaft for the movable part 4. Similarly, the shaft 20 </ b> B functions as a guide shaft for the movable portion 5, and functions as a drive shaft for the movable portion 4.

  The imaging device 1D according to the present embodiment has the same effects as the imaging device 1 according to the first embodiment, and further, the distance between the two movable parts 4 and 5 each of which is a lens unit part is variable. Therefore, zooming is possible.

<Fifth embodiment>
Next, an imaging device 1E and a manufacturing method of the imaging device 1E according to the fifth embodiment of the present invention will be described. Since the imaging device 1E and the manufacturing method of the imaging device 1E of the present embodiment are similar to the imaging device 1 and the manufacturing method of the imaging device 1 of the first embodiment, the same components are denoted by the same reference numerals, Description is omitted.

  As shown in FIG. 12, the fixing unit 3E of the imaging device 1E includes a CCD substrate unit 40E, a piezoelectric element substrate unit 30E1 including a piezoelectric substrate unit 31E having electrode films 32E and 33E, a piezoelectric element substrate unit 30E2, and a flat plate shape. The two drive shafts 20E1 and 20E2 and two flat guide shafts 21E1 and 21E2, and the movable portion 6 is fitted between the shafts 20E1, 20E2, 21E1 and 21E2. Match. Elastic bodies 20M1 and 20M2 for improving driving characteristics are disposed on the fitting surface. The wirings 32S1 and 32S2 are side wirings of the upper electrode film of the piezoelectric element substrate portions 30E1 and 30E2. The movable portion 6 is a lens unit portion having lens substrate portions 11E and 13E and spacer substrate portions 12E and 13E.

  In the imaging device 1E, the movable portion 6 moves in the vertical direction by synchronously driving the piezoelectric element substrate portions 30E1 and 30E2. Note that the drive shaft may surround four side surfaces of the movable portion 6. Further, the shaft may be divided into a plurality of columns.

  The image pickup apparatus 1E has the same effect as the image pickup apparatus 1, and has excellent driving characteristics due to the large area of the fitting surface.

  The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1, 1B, 1C, 1D, 1E ... Imaging device 2, 2B, 2C ... Movable part, 2A ... Movable part substrate, 2H1, 2H2, 2H3, 2H4, 2H5, 2H6 ... Through-hole, 3, 3A, 3B, 3E ... fixed portion, 3A ... fixed portion substrate, 4, 5, 6 ... movable portion, 11, 11D, 11E ... lens substrate portion, 11A ... lens substrate, 11L, 13L ... lens portion, 12, 12D, 12E ... spacer substrate portion , 12A ... spacer substrate, 13, 13E ... lens substrate portion, 13A ... lens substrate, 14, 14E ... spacer substrate portion, 14A ... spacer substrate, 15 ... fitting substrate portion, 15H ... through hole, 20, 20B, 20E1, 20E2, 21, 21E1, 21E2 ... shaft, 20A, 21A ... hole, 20M ... elastic body, 28 ... small hole, 29A ... setup substrate, 30, 30B, 30E1, 30E2 ... piezoelectric element Substrate portion, 30A ... piezoelectric element substrate, 31, 31B ... piezoelectric substrate portion, 31A, 31E ... piezoelectric substrate, 32, 32A, 32B, 32E ... electrode film, 32T, 32TB ... through wiring, 32S, 32S1, 32S2 ... wiring, 33, 33A, 33B, 33E ... electrode film, 33T ... through wiring, 38A ... mask layer, 39A ... holding substrate, 40, 40B, 40C, 40E ... CCD substrate portion, 40A ... CCD substrate, 41T ... through wiring, 42, 43, 43B, 44, 45 ... electrodes, 49A ... holding substrate, 50 ... fixed substrate portion, 50A ... fixed portion substrate

Claims (15)

An imaging device comprising a fixed part and a movable part,
The fixing part is
An image sensor substrate having an image sensor;
A piezoelectric element substrate unit that is bonded to the imaging element substrate unit and that is composed of a piezoelectric substrate unit having electrode films on both sides thereof, and vibrates in a film surface direction;
A shaft that is erected on the piezoelectric element substrate portion and transmits vibrations of the piezoelectric element substrate portion;
The movable part is
A lens unit movable in the longitudinal direction of the shaft;
An image sensor substrate in which the image sensor is arranged in a grid pattern and a piezoelectric element substrate in which the piezoelectric element substrate unit is arranged in a grid pattern are separated from the fixed unit substrate to which the fixed element is separated. On the shaft,
The movable portion separated from a movable portion substrate in which a lens substrate in which a plurality of lens substrate portions are arranged in a lattice shape and a spacer substrate in which a plurality of spacer substrate portions are arranged in the lattice shape are joined. An imaging device characterized by being fitted. A plurality of through holes are formed in a lattice shape on the movable part substrate,
The imaging apparatus according to claim 1, wherein the movable portion is fitted to the shaft of the fixed portion through the through hole.   The imaging apparatus according to claim 2, wherein a film thickness of the electrode film provided upright by the shaft is larger than a film thickness of one of the electrode films.   The imaging apparatus according to claim 3, wherein the shape when observed from the upper surface of the movable portion is a rectangle, and the through hole is formed in at least one of the four corners of the rectangle. The fixed portion includes a plurality of the piezoelectric element substrate portions and a plurality of the shafts,
The imaging device according to claim 4, wherein a plurality of through holes that fit into the plurality of shafts are formed in the movable portion. A plurality of the movable parts;
The fixed portion includes a plurality of the piezoelectric element substrate portions and a plurality of the shafts,
The imaging apparatus according to claim 4, wherein each of the plurality of movable portions is formed with a through hole that fits with each of the plurality of shafts.   The imaging device according to any one of claims 1 to 6, wherein a material forming the through hole and a material of the shaft have different thermal expansion coefficients. A method for manufacturing an imaging device including a fixed portion and a movable portion,
An imaging element substrate creating step in which an imaging element substrate having an imaging element substrate portion having an imaging element is arranged in a grid pattern; and
A piezoelectric element substrate creating step in which a piezoelectric element substrate having electrode films on both sides of the piezoelectric substrate is created;
A piezoelectric element patterning step in which the piezoelectric element substrate is patterned on the plurality of piezoelectric element substrate portions arranged in the lattice pattern;
The imaging element substrate / piezoelectric element substrate joining step in which the imaging element substrate and the patterned piezoelectric element substrate are joined, and the imaging element substrate part and the fixed part substrate having the piezoelectric element are cut, A fixed substrate part singulation process separated into fixed substrate parts;
A shaft setup process in which a shaft is erected on the piezoelectric element substrate portion and a fixed portion is created,
A lens unit substrate in which a lens substrate in which a plurality of lens substrate portions are arranged in a lattice pattern and a spacer substrate in which a plurality of spacer substrate portions are arranged in the lattice shape is cut, and cut into individual movable portions. The movable part singulation process to be separated,
An assembly process in which the shaft of the fixed part and the movable part are fitted to each other. In the lens unit substrate, a plurality of through holes arranged in the lattice shape are formed,
The method of manufacturing an imaging apparatus according to claim 8, wherein the shaft and the through hole are fitted in the assembly step. Before the piezoelectric element patterning step, the piezoelectric element substrate / holding substrate bonding step in which the piezoelectric element substrate is bonded to the holding substrate,
The method for manufacturing an imaging apparatus according to claim 9, further comprising a holding substrate separation step in which the holding substrate is separated from the piezoelectric element substrate after the imaging element substrate / piezoelectric element substrate bonding step.   The method of manufacturing an imaging apparatus according to claim 10, wherein a film thickness of the electrode film on the upper surface of the piezoelectric element substrate portion is larger than a film thickness of the electrode film on the lower surface.   12. The method of manufacturing an imaging device according to claim 11, wherein the shape of the movable part when viewed from above is a rectangle, and the through hole is formed in at least one of the four corners of the rectangle. . The fixed portion includes a plurality of the piezoelectric element substrate portions and a plurality of the shafts,
The method of manufacturing an imaging apparatus according to claim 11, wherein the movable portion is formed with a plurality of through-holes that fit into the plurality of shafts. A plurality of the movable parts;
The fixed portion includes a plurality of the piezoelectric element substrate portions and a plurality of the shafts,
The method of manufacturing an imaging apparatus according to claim 11, wherein each of the plurality of movable portions is formed with a through hole that fits with each of the plurality of shafts. The material that forms the through hole and the material of the shaft are different in thermal expansion coefficient.
The method of manufacturing an imaging apparatus according to claim 8, wherein the shaft is fitted into the through hole while being heated or cooled in the assembly step.

Images