JP2002270804A - Solid-state imaging device, its manufacturing method, image reading unit, and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-state imaging device which can eliminate, as much as possible adverse effects, such as refraction, scattering, etc., due to air bubbles, and to obtain high quality image. SOLUTION: In this solid-state imaging device, the pixel effective area 75a of a CCD bare chip 75 faces opposite to a glass substrate, a transparent adhesive agent S1 is interposed between the CCD bare chip 75 and glass substrate 71, and the CCD bare chip 75 is mounted on the glass substrate 71. In this case, air bubbles b, mixed in the transmitting area of the adhesive agent S1 where a light enters the pixel effective area 75a, is made smaller in size than the pixel of the CCD bare chip 74.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, an image scanner, and a facsimile.
The present invention relates to a solid-state imaging device of an image reading device that reads an optical image using a solid-state imaging device, a method of manufacturing the same, an image reading unit, and an image forming device. It can be applied.

[0002]

2. Description of the Related Art In a conventional flip-chip mounting method for a semiconductor element, as shown in FIG. 7, a semiconductor element 175 and a circuit pattern 173 on a substrate 171 are electrically connected by bumps 174 and a liquid adhesive is used. By injecting 172 between the substrate 171 and the semiconductor element 175, the substrate 717 and the semiconductor element 175 are connected.
Therefore, air is mixed into the adhesive 172 when the adhesive 172 is injected, and bubbles b are formed when the adhesive 172 is fixed. Since the bubbles b weaken the adhesive force, there is a problem that the substrate 171 is easily peeled off after the semiconductor element 175 is mounted on the substrate 171.

Therefore, as a means for removing bubbles b in the adhesive 172, a "resin sealing method" (JP-A-8-3067) is used.
No. 17), there is a method of heating the adhesive or applying ultrasonic vibration to remove bubbles in the adhesive.

[0004]

However, in the conventional method as described above, during the filling of the adhesive, minute bubbles may be entrained or gas may be generated depending on the surface condition of the semiconductor chip, the substrate, the bonding electrode and the like. Are generated, and they expand in the course of heat curing to generate a force for peeling off the bonding electrode, thereby causing a problem that the bonding between the semiconductor chip and the substrate is broken.

Further, in the solid-state imaging device, the semiconductor element 1
75, a substrate 171 and an adhesive 172, respectively, a solid-state imaging device, a transparent substrate, and a transparent adhesive are used, and light enters into fine pixels of the solid-state imaging device. Even if it can be removed, the effect of the fine bubbles is extremely large. That is, in the solid-state imaging device, when fine bubbles b occur in the transparent adhesive 172, a difference in refractive index occurs between the adhesive 172 and the inside of the fine bubbles b, and light transmitted through the adhesive 172 is generated. However, there is a problem that the light is refracted or scattered, thereby impairing the reading performance.

Accordingly, the present invention provides a solid-state imaging device capable of extremely reducing adverse effects such as refraction and scattering due to air bubbles and obtaining a high-quality image, a method of manufacturing the same, an image reading unit and an image forming apparatus. Its purpose is to provide.

[0007]

According to a first aspect of the present invention, a pixel effective area of a solid-state imaging device is opposed to a transparent member, and a transparent region is provided between the solid-state imaging device and the transparent member. In a solid-state imaging device in which the solid-state imaging device is mounted on the transparent member with an adhesive interposed therebetween, the size of bubbles mixed in a transparent adhesive transmission region through which light incident on the pixel effective area is transmitted. Is smaller than the size of a pixel of the solid-state imaging device. The invention according to claim 2 is characterized in that the size of the bubble is smaller than the bubble outside the transmission region.
2. The solid-state imaging device according to item 1. Further, according to the invention of claim 3, the pixel effective area of the solid-state imaging device faces the transparent member,
In a solid-state imaging device in which a transparent adhesive is interposed between the solid-state imaging device and the transparent member, and the solid-state imaging device is mounted on the transparent member, between the solid-state imaging device and the transparent member A transparent adhesive that covers the pixel effective area of the solid-state imaging element and is filled in a thin layer, and a bump that conducts between the solid-state imaging element and the wiring pattern of the transparent member; The solid-state imaging device is characterized in that the size of bubbles mixed into the transparent adhesive transmitting area through which the incident light is transmitted is smaller than the size of the pixel of the solid-state imaging device. According to a fourth aspect of the present invention, the pixel effective area of the solid-state imaging device faces the transparent member, a transparent adhesive is interposed between the solid-state imaging device and the transparent member, and the solid-state imaging device is mounted on the transparent member. In the solid-state imaging device, a projection for thinning a transparent adhesive between a pixel effective area of the imaging element and the transparent member, and a wiring pattern between the imaging element and the transparent member are provided. A conductive resin, a sealing resin for bonding the outer periphery of the imaging element and the transparent member, and air bubbles mixed in a transparent adhesive transmitting area through which light incident on the pixel effective area passes. Is smaller than the size of the pixel of the solid-state imaging device. According to a fifth aspect of the present invention, the pixel effective area of the solid-state imaging device faces the transparent member, a transparent adhesive is interposed between the solid-state imaging device and the transparent member, and the solid-state imaging device is mounted on the transparent member. In the method of manufacturing a solid-state imaging device, after filling a transparent adhesive between the solid-state imaging device and the transparent member under a low-pressure atmosphere, the transparent adhesive is pressed under a high-pressure atmosphere, A method for manufacturing a solid-state imaging device, wherein the transparent adhesive is cured while maintaining a pressurized state.
The invention according to claim 6 is the method for manufacturing a solid-state imaging device according to claim 5, wherein an ultraviolet curable adhesive is used as the transparent adhesive, and the adhesive is cured by ultraviolet light. In the invention according to claim 7, the pressurizing under the high-pressure atmosphere is performed until the size of the bubbles mixed in the transparent adhesive at the time of filling becomes smaller than the size of the pixel of the solid-state imaging device. 7. A method for manufacturing a solid-state imaging device according to claim 5, wherein The invention according to claim 8 is the method for manufacturing a solid-state imaging device according to claim 7, wherein the filling of the transparent adhesive is performed from the bump side. According to a ninth aspect of the present invention, there is provided an image reading unit including the solid-state imaging device according to any one of the first to fourth aspects. According to a tenth aspect of the present invention, there is provided an image forming apparatus including the image reading unit according to the ninth aspect.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating a method for manufacturing the solid-state imaging device according to the first embodiment of the present invention. As shown in FIG. 1C, the solid-state imaging device 7 includes an integrated circuit for converting light information such as a line CCD and an area CCD into an electric signal.
A wiring board 73 for electrical connection is disposed facing the circuit forming surface of the D bare chip 75, that is, a glass substrate 71 which is a transparent member disposed in a face-down state;
Conductivity is provided between the D bare chip 75 and the glass substrate 71 and between the transparent adhesive S1 filling and covering the pixel effective area 75a of the CCD bare chip 75 and the wiring pattern 73 of the CCD bare chip 75 and the glass substrate 71. Bumps 74 to be formed.

The CCD bare chip 75 is formed by forming a circuit on a silicon wafer and cutting it to a required size. When mounted, the flatness of the pixel portion is required. Is formed. Further, since the CCD bare chip 75 is adversely affected by dust, dew, and the like due to the external atmosphere, it is necessary to be shielded from the external atmosphere.

The glass substrate 71 is made of a member having a high light transmittance, and a portion through which light incident on the pixel effective area 75a passes is formed to a required flatness. Further, a wiring pattern 73 as an electric circuit is formed on the surface of the glass substrate 71 on which the CCD bare chip 75 is mounted.

The adhesive S1 fixes the CCD bare chip 75 and seals the pixel effective area 75a. The filling amount of the adhesive S1 is the CCD bare chip 75
Is larger than the product of the pixel effective area 75a and the thickness of the adhesive S1 layer, the entire pixel effective area 75a is uniformly covered with the transparent adhesive S1, so that the influence of the transparent adhesive S1 on each pixel is constant. Becomes The pixel effective area 75
“a” is an area on the image sensor where the photocell array (the part of the circuit for reading an image of the image sensor) is provided.

In order to manufacture the solid-state imaging device as described above, first, as shown in FIG. 1A, a CCD bare chip 75 is placed face down on a surface of a glass substrate 71 on a wiring pattern 73 side. The CCD bare chip 75 and the glass substrate 71 are brought close to a predetermined distance so that the CCD bare chip 75 and the wiring pattern 73 of the glass substrate 71 are electrically connected by the bumps 74.
Adhesive S between CD bear chip 75 and glass substrate 71
1 is filled from an injector 78 such as a dispenser. The filling method is such that when the filler 78 is dropped on the first to third sides of the CCD bare chip 75 using the injector 78, the adhesive S1 flows between the glass substrate 71 and the CCD bare chip 75 due to the surface tension of the adhesive S1. Will be filled. In this embodiment, the filling is performed under normal pressure or atmospheric pressure, that is, under a low-pressure atmosphere.

As shown in FIG. 1B, since the distance between the CCD bare chip 75 and the glass substrate 71 is small, the adhesive S
1 can be easily filled by surface tension and capillary action. The pixel region 75a is covered with the adhesive S1 thus filled. At this time, bubbles b may be mixed in the adhesive S1.

Thereafter, as shown in FIG.
(B) is put in a pressure vessel 79, and the pressure vessel 79
The inside temperature is kept or cooled, and a pressure higher than the pressure when the adhesive S1 is filled is applied. That is, for example, the sealed space M in the pressure vessel 79 is made into a high-pressure atmosphere higher than a low-pressure atmosphere (normal pressure or atmospheric pressure) by a compressor 80 or the like, and ultraviolet light is applied from the ultraviolet light source V to the adhesive S1 in this high-pressure atmosphere. To cure. The magnitude of the pressure at this time is appropriately set to a pressure at which the bubble b becomes sufficiently small.

At this time, air bubbles b contained in the adhesive S1
According to Boyle-Charles' law, the volume of the air bubble becomes smaller than that of the air bubble b mixed at the time of filling the adhesive. In this state, for example, when an ultraviolet curable adhesive is used as the adhesive S1 as in the present embodiment, the adhesive S1 is cured by irradiating ultraviolet rays. In this way, it is possible to reduce the volume of the bubble b in the incident light passing range H of at least the pixel effective area 75a of the adhesive S1.

FIG. 1C shows the case where the ultraviolet light source V is disposed inside the pressure vessel 79. However, when the pressure vessel 79 is made of a transparent member such as glass, the outside of the pressure vessel 79 is shown. UV light source V is placed on the adhesive S
1 may be irradiated. When a photo-curing adhesive other than the ultraviolet-curing adhesive is used, it can be cured by irradiating the curing light. When a transparent adhesive other than an ultraviolet curable type or a light curable type is used, the bubble b can be similarly reduced by curing while maintaining the state where the bubble b is reduced as described above. .

FIG. 2 is a view showing a method of manufacturing a solid-state imaging device according to a second embodiment of the present invention. As shown in FIG. 2C, the difference between the solid-state imaging device 7 of the second embodiment and the solid-state imaging device 7 of the first embodiment is that the glass substrate 71
The point is that a protrusion 71a having a height C is formed on the side facing the CD bear chip 75, that is, on the side of the wiring pattern 73 for electrical connection. The projecting portion 71a is a CCD bare chip 7
The pixel effective area 75a on the glass substrate 71 side corresponding to the 5 pixel effective area 75a is formed. That is, the CCD bare chip 75 is formed to have a size that does not impede a light beam incident on the pixel effective area 75a.

The bump 74 has a projection shape for establishing conduction between the CCD bare chip 75 and the wiring pattern 73 of the glass substrate 71. The height A of the bump 74 is the same as the thickness B of the thinned adhesive S1. It is formed higher than the distance in the thickness direction from the adhesive S1 to the wiring pattern 73, that is, the sum of the height C of the protrusion 71a. Thus, conduction between the CCD bare chip 75 and the electric circuit of the glass substrate 71 can be ensured, and the flatness of the CCD bare chip 75 can be maintained.

The periphery of the bump 74 is sealed with a sealing resin S2 different from the adhesive S1. Therefore, the bump 74 is also in a sealed state. Since the bubbles mixed into the sealing resin S2 are outside the incident light passage range H, they do not affect the light incident on the pixel effective area 75a, and may be larger than the bubbles in the adhesive S1.

The sealing resin may be the same as the adhesive S1. As described above, the sealing resin may be transparent, but need not be transparent, and the present embodiment uses an opaque resin. By using such an opaque resin, it is possible to prevent unnecessary light from entering the pixel effective area 75a of the CCD bare chip 75, so that the image quality is improved. Further, since it is not necessary to use expensive transparent resin, it is advantageous in cost as compared with the case where transparent resin is used. It is desirable that the sealing resin has a low coefficient of thermal expansion.

The adhesive S1 fixes the CCD bare chip 75 and seals the pixel effective area 75a. The filling amount of the adhesive S1 is the CCD bare chip 75
Is larger than the product of the thickness of the thinned adhesive S1 layer and the pixel effective area 75a of the pixel effective area 75a.
Since the entire area a is uniformly covered with the transparent adhesive S1, it is possible to prevent air bubbles from being mixed in, and the effect of the transparent adhesive S1 on each pixel becomes constant.

To manufacture the solid-state imaging device as described above, first, as shown in FIG. 2A, the CCD bare chip 75 is placed face down on the surface of the wiring pattern 73 provided on the glass substrate 71. To face.

Next, as in the first embodiment, the CCD bare chip 75 is connected to the wiring pattern 73 of the glass substrate 71 by the bump 74 so that the CCD bare chip 75 is electrically connected to the wiring pattern 73 of the glass substrate 71.
And the glass substrate 71 are brought close to a predetermined distance, and then the adhesive S1 is filled between the CCD bare chip 75 and the glass substrate 71. At this time, the CCD is thin enough to
Since the distance between the bare chip 75 and the glass substrate 71 is small, the adhesive S1 can be easily filled by the surface tension and the capillary action. The adhesive S1 filled in this way is thinned to cover the pixel area. 2A, before the CCD bare chip 75 is overlaid on the glass substrate 71, the protrusion 71a of the glass substrate 71 is filled.
The above-mentioned required amount may be placed on the above.

The filling amount of the adhesive S1 is an amount that can cover the pixel effective area 75a of the CCD bare chip 75.
That is, an amount slightly larger than the volume between the surface of the CCD bare chip 75 on the pixel effective area side and the protrusion 71 a of the glass substrate 71 is filled. This slightly larger amount is such that a space S is formed between the connection portion between the bump 74 and the wiring pattern 73 and the thinned adhesive S1. Note that, as shown by the dashed line in FIG.
By forming an annular groove between the projection 71a and the conductive part of the bump 74 so as to surround the periphery of the projection 71a, this groove becomes a pool for the adhesive S1 and reliably forms the space S.
Can be formed.

Next, as shown in FIG. 2B, the adhesive S1 is cured under a high-pressure atmosphere in the same manner as in the first embodiment. Thereafter, as shown in FIG.
Of the glass substrate 71, that is, the sealing resin S
2 to seal the bump 74 and the inside of the bump 74. That is, the entirety of the pixel effective area 75a including the conductive bumps 74 is filled with the sealing resin S2 and cured.

FIG. 3 is a diagram showing a method of manufacturing a solid-state imaging device according to a third embodiment of the present invention. As shown in FIG. 3C, the difference between the solid-state imaging device 7 of the third embodiment and the solid-state imaging device 7 of the second embodiment is that
Is the side facing the glass substrate 71, that is, the pixel effective area 7
The point is that a projection 75b having a height C is formed on the 5a side. The projection 75b is formed so as to include the pixel effective area 75a of the CCD bare chip 75.

The bump 74 has a projection shape for establishing electrical connection between the CCD bare chip 75 and the wiring pattern 73 of the glass substrate 71. The height A of the bump 74 is equal to the thickness B of the thinned adhesive S1. It is formed higher than the distance in the thickness direction from the adhesive S1 to the wiring pattern 73, that is, the sum of the height C of the protrusion 75b. Thus, conduction between the CCD bare chip 75 and the electric circuit of the glass substrate 71 can be ensured, and the flatness of the CCD bare chip 75 can be maintained.

The periphery of the bump 74 is sealed with a sealing resin S2 different from the adhesive S1, as in the second embodiment. Therefore, the bump 74 is also in a sealed state.

The adhesive S1 fixes the CCD bare chip 75 and seals the pixel effective area 75a. The filling amount of the adhesive S1 is the CCD bare chip 75
Pixel effective area 75a and the thickness B of the thinned adhesive layer
And the pixel effective area 75a
Since the whole is uniformly covered with the transparent adhesive S1, it is possible to prevent air bubbles from being mixed in, and the effect of the transparent adhesive S1 on each pixel is constant.

To manufacture the solid-state imaging device as described above, as in the second embodiment, first, as shown in FIG. 3A, a CCD bare chip 75 is provided on a glass substrate 71 face down. To the surface on the wiring pattern 73 side.

Next, similarly to the second embodiment, the filled adhesive S1 is thinned to cover the pixel area. The filling amount of the adhesive S1 is an amount that can cover the pixel effective area 75a of the CCD bare chip 75. That is, an amount slightly larger than the volume between the surface of the projection 75b including the pixel effective area 75a of the CCD bare chip 75 and the corresponding portion of the glass substrate 71 is filled. This slightly larger amount is such that a space S is formed between the connection portion between the bump 74 and the wiring pattern 73 and the thinned adhesive S1.

As shown by a dashed line in FIG. 3C, a portion corresponding to the projection 75b is surrounded between the portion corresponding to the projection of the CCD bare chip 75 and the conductive portion of the bump 74. By forming the annular groove as described above, the groove becomes a reservoir for the adhesive, so that the space S can be reliably formed.

Next, as shown in FIG. 3B, the adhesive S1 is cured under a high-pressure atmosphere in the same manner as in the second embodiment. Thereafter, as shown in FIG. 3C, the entire periphery of the pixel effective area 75a including the conductive bumps 74 is filled with a sealing resin and cured as in the second embodiment.

FIG. 4 is a perspective view of the solid-state imaging device shown in FIGS. 1 to 3. The solid-state imaging device as shown in FIG. 4 is manufactured as described above. In FIG. 4, reference numeral 77 denotes an FPC (flexible wiring board) connected to the wiring pattern 73, and reference numeral L denotes incident light from the imaging lens. In FIG. 4, in the case of the solid-state imaging device of FIGS.
1a is omitted.

FIG. 5 is a perspective view of an image reading unit using the solid-state imaging device according to the present invention. As shown in FIG.
The image reading unit 1 includes a lens 3 as an optical element having a side surface 3a as a side surface around a transmission surface through which light rays as image light from a document surface are transmitted, and a first attachment facing the edge surface 3a. The angle between the surface 5a and the first mounting surface 5a is different from that of the first mounting surface 5a.
A base member having an intermediate holding member 5 for joining the lens 3 and the housing 2 and a mounting surface 2c opposed to the second mounting surface 5b. And a certain housing 2. In this image reading unit 1,
The housing 2 and the lens 3 whose position has been adjusted with respect to the housing 2 are adhesively fixed via an intermediate holding member 5.

The lens 3 has a flat surface 3b arranged on the edge 3a on the same diameter. The flat surface 3b is formed by cutting, grinding, or the like, and is polished as necessary. By forming the flat surface 3b in this manner, the bonding area of the intermediate holding member 5 with the first mounting surface 5a can be increased, and the fixing strength can be increased.

The housing 2 includes a lens 3 and a solid-state imaging device 7.
Are fixed in the adjusted positional relationship after the adjustment. The housing 2 is an imaging lens including an arc-shaped groove 2b, a flat mounting surface 2c adjacent to the arc-shaped groove 2b, a mounting surface 2d for mounting the solid-state imaging device 7, and lenses 3, 6, and the like. A light-shielding cover 2a that shields light between the system and the solid-state imaging device 7 is provided. By providing the light-shielding cover 2a, the influence of disturbance light or the like can be prevented, and a good image can be obtained. The housing 2 is fixed to a predetermined position of an image scanning device such as a copying machine to be described later by fixing means such as screwing, caulking, bonding, welding, or the like.

As the material used for the intermediate holding member 5, a member having a high light (ultraviolet) transmittance, for example, ARTON, ZEONEX, polycarbonate or the like is used. Due to the surface tension of the adhesive, the intermediate holding member 5 can move so that both adhesive surfaces slide and move following the movement of the lens 3 due to the lens position adjustment by the lens adjustment.

By making the first mounting surface 5a and the second mounting surface 5b of the intermediate holding member 5, that is, both bonding surfaces orthogonal, the position of the lens 3 can be adjusted in six axes, and each axis can be adjusted independently. Can be.

As shown in FIG. 5, the two intermediate holding members 5
By arranging the flat surface 3b of the edge 3a of the lens 3 which is the optical element side bonding surface so as to face the optical element side, the influence of curing shrinkage when the adhesive is cured can be reduced.

As shown in FIG. 5, the provision of the translucent ribs 5c between the two adhering surfaces of the intermediate holding member 5 allows the light curable adhesive to be cured without increasing light loss. The strength of the intermediate holding member 5 can be increased.

Since the first mounting surface 5a, which is the lens-side fixing surface of the intermediate holding member 5, is perpendicular to the second mounting surface 5b, which is the holding member-side fixing surface, the X, Y, Z,
The movement in the α, β, and γ position adjustment directions can be adjusted independently of each other.

Considering the case where the intermediate holding member 5 is connected to the adjusting lens 3 and the housing 2 by an ultraviolet curing adhesive, first, in the case of adjustment in the X and Z directions, the lens 3 and the intermediate holding member are connected. The member 5 is adjusted by sliding on the housing via the housing mounting surface 2c, which is a holding member-side fixing surface of the housing 2. In the case of adjustment in the Y direction, the adjustment is performed by the moving lens 3 sliding on the first mounting surface 5a, which is the lens-side fixing surface of the intermediate holding member 5.

Hereinafter, α, β, and γ are similarly adjusted.
Furthermore, when the optical element is a lens, it has a spherical shape with the optical axis as the center. Therefore, even if the optical element is rotated around the optical axis (γ axis), it is not possible to correct the optical axis tilt caused by a lens processing error or the like. No (only the optical axis rotates). Therefore, adjustment around the γ-axis is unnecessary.

FIG. 6 is a schematic configuration diagram of a multifunctional digital image forming apparatus as an example of an image scanning apparatus provided with an image reading unit using the solid-state imaging device of the present invention. As shown in FIG. 6, the image forming apparatus includes an automatic document feeder 10
1, a reading unit 150, a writing unit 157, a sheet feeding unit 130, and a post-processing unit 140. The automatic document feeder 101 automatically feeds a document onto the contact glass 106 of the reading unit 150 and automatically discharges the document that has been read. The reading unit 150 is a contact glass 106
The original set above is illuminated and read by the solid-state imaging device 7 which is a photoelectric conversion device, and the writing unit 157 forms an image on the photoconductor 115 according to the image signal of the read original, and a paper feeding unit The image is transferred and fixed on the transfer paper fed from 130. The transfer paper on which the fixing is completed is discharged to the post-processing unit 140, and desired post-processing such as sorting and stapling is performed.

First, the reading unit 150 includes a contact glass 106 on which a document is placed and an optical scanning system. The optical scanning system includes an exposure lamp 151 and a first mirror 15.
2, a lens 3, a solid-state imaging device 7, a second mirror 155, a third mirror 156, and the like. Exposure lamp 1
51 and the first mirror 152 are fixed on a first carriage (not shown), and the second mirror 155 and the third mirror 1
56 is fixed on a second carriage (not shown).
When reading an original, make sure that the first
The carriage and the second carriage are mechanically scanned at a relative speed of 2: 1. This optical scanning system is driven by a scanner drive motor (not shown).

The original image is read by the solid-state imaging device 7, converted from an optical signal to an electric signal, and processed. The image magnification can be changed by moving the lens 3 and the solid-state imaging device 7 in the left-right direction in FIG. That is, the position of the lens 3 and the solid-state imaging device 7 in the left-right direction in the figure is set corresponding to the designated magnification.

The writing unit 157 includes a laser output unit 158, an imaging lens 159, and a mirror 160. Inside the laser output unit 158,
A polygon mirror that rotates at high speed at a constant speed by a laser diode and a motor as a laser light source is provided.

The laser light emitted from the laser output unit 158 is deflected by the polygon mirror that rotates at a constant speed, passes through the imaging lens 159, is turned back by the mirror 160, and is condensed on the photoreceptor surface to form an image. . The deflected laser light is exposed and scanned in a so-called main scanning direction orthogonal to the direction in which the photoconductor 115 rotates.
The image signal output by the SU 606 is recorded in line units. Then, an image, that is, an electrostatic latent image is formed on the photoconductor surface by repeating main scanning at a predetermined cycle corresponding to the rotation speed and the recording density of the photoconductor 115.

As described above, the laser beam output from the writing unit 157 is applied to the photosensitive member 115 of the image forming system, and a main scanning synchronization signal is generated at the irradiation position of the laser beam near one end of the photosensitive member 115. A beam sensor (not shown) is provided. Based on the main scanning synchronization signal output from the beam sensor, control of image recording timing in the main scanning direction and generation of a control signal for input / output of an image signal described later are performed.

The present invention is not limited to the above embodiment. For example, in the above embodiment, the bump 74
Is provided on the CCD bare chip 75 side, but the glass substrate 7
Of course, it may be provided on one side. Further, in the above embodiment, the glass substrate 71 is used as the transparent member. However, other than the glass substrate 71, a member having high light transmittance such as plastic for a lens may be used. Further, in the above embodiment, an ultraviolet curable adhesive is used as the adhesive S1, but other light curable adhesives may be used, or other adhesives having transparency after curing may be used. Good. For example, an adhesive having high optical properties, for example, balsam, epoxy resin, fluorine resin, silicon, or the like can be used. In the above embodiment, the connection between the CCD bare chip 75 and the glass substrate 71 is also performed by the adhesive S1 or the sealing resin S2. The stopping resin S2 can be omitted. That is, various modifications can be made without departing from the gist of the present invention.

[0052]

As described above, according to the first aspect of the present invention, the transparent adhesive filled between the transparent member and the solid-state imaging device is made transparent while applying a higher pressure than when the transparent adhesive is filled. By curing the adhesive, the size of the bubbles in the transparent adhesive can be reduced, and as a result, the bubbles are refracted by the bubbles compared to when cured without applying pressure.
Scattered light is reduced, and image quality can be improved. Further, according to the second aspect of the present invention, it is possible to further reduce bubbles only in a portion that affects image quality. According to the third aspect of the present invention, the air bubble is refracted by the air bubble,
The amount of scattered light can be reduced and the image quality can be improved, and the resin layer is thinned, so that a good image can be obtained. Further, since the warpage of the solid-state imaging device itself can be prevented, the pixel pitch can be reduced. Can be prevented from deteriorating such as fluctuation of optical characteristics. According to the fourth aspect of the invention, the bumps can be sealed, and the amount of light refracted and scattered by the bubbles is reduced, so that the image quality can be improved. Further, according to the fifth aspect of the present invention, it is possible to obtain a solid-state imaging device in which light refracted and scattered by air bubbles is reduced and image quality can be improved. Further, according to the invention of claim 6, since the ultraviolet curable resin is used, the curing time is short, and the manufacturing time can be shortened. Further, according to the invention of claim 7, the size of the bubble can be made smaller than that of the pixel, and at least a part of the light incident on the pixel can be secured. Further, according to the invention of claim 8, since the transparent adhesive is further filled from the bump side, it can be filled in the lateral direction of the solid-state imaging device. Further, according to the ninth aspect of the present invention, it is possible to obtain an image reading unit having the effect of any one of the first to fourth aspects. According to the tenth aspect, an image forming apparatus having the effect of the ninth aspect can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method for manufacturing a solid-state imaging device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a method for manufacturing a solid-state imaging device according to a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a method for manufacturing a solid-state imaging device according to a third embodiment of the present invention.

FIG. 4 is a perspective view of the solid-state imaging device of FIGS.

FIG. 5 is a perspective view of an image reading unit using the solid-state imaging device according to the present invention.

FIG. 6 is a schematic configuration diagram of a multifunctional digital image forming apparatus as an example of an image scanning apparatus including an image reading unit using the solid-state imaging device of the present invention.

FIG. 7 is a diagram illustrating a conventional flip-chip mounting method of a semiconductor element.

[Explanation of symbols]

 Reference Signs List 1 Image reading unit 71 Glass substrate (transparent member) 71a Projection 73 Wiring pattern 74 Bump 75 CCD bare chip (solid-state image sensor) 75a Pixel effective area 75b Projection b Air bubble H Light incident area S1 Transparent adhesive S2 Sealing resin

Claims (10)

[Claims] 1. A pixel effective area of a solid-state imaging device faces a transparent member, a transparent adhesive is interposed between the solid-state imaging device and the transparent member, and the solid-state imaging device is mounted on the transparent member. In the solid-state imaging device, the size of bubbles mixed into the transparent adhesive transmission area through which light incident on the pixel effective area is transmitted is smaller than the size of the pixel of the solid-state imaging device. apparatus. 2. The solid-state imaging device according to claim 1, wherein the size of the bubble is smaller than that of the bubble outside the transmission region. 3. The solid-state image sensor is mounted on the transparent member, with a pixel effective area of the solid-state image sensor facing the transparent member and a transparent adhesive interposed between the solid-state image sensor and the transparent member. In the solid-state imaging device, between the solid-state imaging device and the transparent member, a transparent adhesive that fills a thin layer and covers a pixel effective area of the solid-state imaging device, The size of bubbles mixed in the transparent conductive material and the bumps that conduct between the wiring pattern of the transparent member and the transparent adhesive that transmits light incident on the pixel effective area is smaller than the size of the pixel of the solid-state imaging device. A solid-state imaging device characterized by the above-mentioned. 4. A solid-state imaging device in which a pixel effective region faces a transparent member, a transparent adhesive is interposed between the solid-state imaging device and the transparent member, and the solid-state imaging device is mounted on the transparent member. In the image pickup apparatus, a protrusion for thinning a transparent adhesive between a pixel effective area of the image pickup device and the transparent member, and a bump for conducting between the image pickup device and a wiring pattern of the transparent member A sealing resin for bonding the outer periphery of the imaging element and the transparent member, and a size of bubbles mixed into a transparent adhesive transmitting area through which light incident on the pixel effective area passes. A solid-state imaging device, which is smaller than a pixel size of the solid-state imaging device. 5. A solid-state imaging device in which a pixel effective area faces a transparent member, a transparent adhesive is interposed between the solid-state imaging device and the transparent member, and the solid-state imaging device is mounted on the transparent member. In the method for manufacturing an imaging device, after filling a transparent adhesive between the solid-state imaging device and the transparent member under a low-pressure atmosphere, the transparent adhesive is pressurized under a high-pressure atmosphere, and the pressurized state is changed. A method of manufacturing a solid-state imaging device, wherein the transparent adhesive is cured while being held. 6. The method according to claim 5, wherein an ultraviolet-curable adhesive is used as the transparent adhesive, and the transparent adhesive is cured by ultraviolet light. 7. The pressurizing under the high-pressure atmosphere is performed until the size of bubbles mixed into the transparent adhesive at the time of filling becomes smaller than the size of a pixel of a solid-state imaging device. A method for manufacturing the solid-state imaging device according to claim 5. 8. The method according to claim 7, wherein the filling of the transparent adhesive is performed from the bump side. 9. An image reading unit comprising the solid-state imaging device according to claim 1. 10. An image forming apparatus comprising the image reading unit according to claim 9.