JP2003066148A - Imaging device, radiation imaging device and image processing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation imaging device of X-rays or the like, in which the performance such as high resolution and dynamic image required for an X-ray digital photographing system for medical diagnosis can be satisfied while ensuring a wide effective area of sensor and reduction of the size of the cost. SOLUTION: Radiation irradiating a subject becomes information of the intensity difference of radiation depending on the information on the subject and then the wavelength of the radiation is converted by a wavelength converter, i.e., a phosphor layer 3, into a a wavelength able to be detected by a photoelectric conversion element. It is passed through a light guide part 2 and an adhesive 6 before being detected at a photoelectric conversion substrate 1 having a plurality of photoelectric conversion elements. Detected information is extended from the pasted part of photoelectric conversion substrates to the rear side by a lead from an I/O circuit on the photoelectric conversion substrate 1 through a bump 5. The lead is bent at the edge of the photoelectric conversion substrate 1 and extended to the side thereof opposite to the side where the photoelectric conversion elements are formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus, a radiation image pickup apparatus and an image processing system, and more particularly to a radiation image pickup apparatus capable of expanding an image pickup range and an image processing system using the same. In the present invention, the radiation refers to α rays, β rays, γ rays and the like including X rays.

[0002]

2. Description of the Related Art For X-ray photography for the purpose of medical diagnosis, a film screen system combining an intensifying screen and an X-ray photographic film is often used. According to this system, the X-ray transmitted through the subject includes information inside the subject,
It is converted into visible light proportional to the intensity of X-rays by an intensifying screen and exposed on an X-ray film.

Recently, X-rays are converted into visible light which is proportional to the intensity of X-rays by a phosphor, converted into electric signals by using a photoelectric conversion element, and converted into digital signals by an AD converter. Digital imaging devices are beginning to be used.

As an example of this, an X-ray digital photographing apparatus in which a phosphor for converting visible light into X-rays is laminated on an image pickup device in which elements in which amorphous semiconductors are sandwiched by electrodes are arranged in a matrix on a substrate made of glass, A photoelectric conversion element such as CCD is arranged on the side where the taper is narrowed by using a taper type optical fiber which is softened and stretched by heat etc., and a module in which phosphors are laminated on the opposite side is two-dimensionally connected. A combined X-ray digital imaging apparatus is known.

The X-ray digital imaging apparatus as described above is mainly used for medical diagnosis and the like, and in order to detect an abnormal portion early and to make an accurate diagnosis, high resolution, low noise, moving image and wide range are used. There is an ever-increasing demand for a shooting area and the like.

However, in the above-mentioned X-ray digital imaging apparatus, in which the semiconductor made of amorphous silicon or the like is used on the glass substrate, the effective size of the sensor can be made large, but the size of the pixel is made fine. Is difficult in terms of process and device characteristics, and has a limited sensitivity, which makes high-speed driving, such as moving image display, difficult.

When a photoelectric conversion element made of a silicon substrate such as a CCD is used, the pixel size can be made fine, and high sensitivity and high speed driving are possible, so that a moving image can be taken easily. However, it is difficult to increase the effective area of the sensor due to the process restriction and the problem of power consumption, that is, heat generation.

Therefore, as shown in FIG. 1, a device is proposed in which the effective area of the sensor is expanded by increasing the number of elements by using an optical fiber processed into a tapered shape so that the non-sensor regions of the photoelectric conversion element do not overlap each other. Has been done. 1 is a substrate on which a photoelectric conversion element is formed, 3 is a scintillator that converts X-rays into light such as visible light having a wavelength that can be detected by the photoelectric conversion element, 7 is a base, 8 is an optical fiber processed into a tapered shape, 9 Is a protective glass, 11 is a bonding wire, 1
2 is a ceramic package.

However, since this tapered optical fiber is expensive, the reduction ratio is not stable due to manufacturing variations, and it is possible to connect several pieces because of its thickness and weight, but the sensor required for chest imaging is effective. To get the area,
Many tapered optical fibers are needed and impractical. Another problem with the tapered optical fiber is that it has a poor light transmittance.

FIG. 2 shows an X-ray moving image system using a conventionally used image intensifier (II). Reference numeral 16 denotes I-I, which converts X-rays incident on the incident surface from light into electrons and doubles the electrons to obtain high sensitivity. An electron is converted into light on the emission surface, and the image of the light is input by the CCD camera 15.

However, in the system using this image intensifier II, since the vacuum tube is used, the size of the apparatus cannot be denied.

In addition, in the CCD image pickup device, since peripheral circuits and electrode areas are required outside the display pixel area portion, the area of the peripheral frame portion outside the effective display area portion is wide as shown in FIG. 3A. In addition, there is a limit to downsizing the X-ray image sensor 82 itself. Note that FIG.
It is an AA 'sectional view of (a).

Especially when an X-ray image sensor used for dental examination is inserted into the oral cavity of a patient and an image is taken,
For example, there are parts such as the back teeth that cannot be photographed depending on the parts. In addition, when the patient is a child, it may be difficult to insert it into the oral cavity or may induce vomiting, which may interfere with photographing.

As described above, the high resolution required for the X-ray digital imaging apparatus for medical diagnosis, the performance such as moving images, the wide sensor effective area, the downsizing of the apparatus, and the cost reduction are compatible with each other. Was difficult.

[0015]

SUMMARY OF THE INVENTION Therefore, the present invention provides a high resolution required for an X-ray digital imaging apparatus for medical diagnosis, performance such as moving images, a wide sensor effective area, downsizing of the apparatus, and cost reduction. A radiation imaging apparatus for X-rays and the like that are compatible with each other, and an image processing system using these are provided, and an area that cannot be imaged during X-ray imaging of teeth is as small as possible (high effective area utilization rate), and X-ray image in the oral cavity. It is intended to reduce the burden on the patient by downsizing the sensor when inserting the sensor.

[0016]

An image pickup apparatus of the present invention is an image pickup apparatus having a plurality of photoelectric conversion elements and a plurality of photoelectric conversion substrates on which input / output terminals connected to the photoelectric conversion elements are arranged. This is achieved by a structure in which the wiring connected to the writing output terminal extends from the gap between the photoelectric conversion substrates to the side opposite to the light receiving surface.

Further, in an image pickup device having a plurality of photoelectric conversion elements and a plurality of photoelectric conversion substrates on which input / output terminals connected to the photoelectric conversion elements are arranged, the input / output terminals are provided with the photoelectric conversion elements. This is achieved by a structure provided on a surface different from the surface.

In addition to these, in addition to these, it is achieved by a radiation imaging device having a wavelength converter on the light receiving surface side of the photoelectric conversion substrate of the imaging device. Further, these image pickup devices, image processing means for image-processing the signals from the image pickup devices, recording means for recording the signals from the image processing means, and display for displaying the signals from the image processing means. It is also achieved by an image processing system characterized in that it has means and a transmission means for transmitting a signal from the image processing means.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The image pickup apparatus of the present invention can be used particularly preferably in the radiation image pickup apparatus described below, but the use is not particularly limited to the radiation image pickup apparatus.

(First Embodiment) FIG. 4 is a sectional view of an image pickup apparatus according to this embodiment, and FIG. 5 is a perspective view thereof. Further, FIG. 5 is a schematic diagram of the photoelectric conversion substrate 1 in the present embodiment.

The radiation applied to the subject becomes information on the difference in the radiation intensity according to the information of the subject, and the radiation is converted into the wavelength detected by the photoelectric conversion element in the phosphor layer 3 as the wavelength converter, and then guided. The light passes through the light section 2 and the adhesive 6, and is detected in the photoelectric conversion substrate 1 having a plurality of photoelectric conversion elements 100. The detected information is extended from the input / output circuit on the photoelectric conversion substrate 1 through the bumps 5 by a conductor such as a lead to a back surface side from a bonding portion between the photoelectric conversion substrates.

The above-mentioned lead is bent at the edge of the photoelectric conversion substrate 1, and the photoelectric conversion element 100 of the photoelectric conversion substrate 1 is bent.
Extends to the side opposite to the surface on which is formed.

The photoelectric conversion substrate 1 is adhered to a common light guide portion 2 by an adhesive 6 so as to be adjacent to each other, and wiring for transferring charges detected from the photoelectric conversion element 100 to a processing circuit is thereby provided. The photoelectric conversion substrate 1 does not have to be provided on the surface, and the effective image pickup area can be increased. Further, particularly in the radiation detector, since some radiation is transmitted through the phosphor 3, it is possible to protect the radiation by extending the wiring and the like to the back side of the substrate. This is especially effective when the photoelectric conversion substrate 1 is a radiation shielding or absorbing member.

FIG. 5 shows a perspective view of the image pickup device. Here, the photoelectric conversion substrate 1 is arranged two-dimensionally in 3 rows × 3 columns, and the leads and the flexible circuit board 4 are provided on the back surface side with respect to the light guide portion 2 from the bonding portions with the respective adjacent substrates. Has been extended to.

FIG. 6 shows the corners of the photoelectric conversion substrate 1. The photoelectric conversion substrate 1 is made of silicon, and has two-dimensionally arranged light receiving pixels (photoelectric conversion elements) 100 and external input / output terminals 10.
Vertical drive circuit 1 for sequentially driving pixels arranged three-dimensionally and two-dimensionally
01, the column scanning circuit 102, and these circuits, pixels,
A wiring 104 that connects the electrode terminals is formed. For example, a CMOS element is preferably used as the photoelectric conversion element.

The light receiving pixels 100 are arranged on almost the entire surface of the photoelectric conversion substrate 1, and the pixel pitch thereof is 100 μm. Further, the input / output terminals 103 are dispersed and arranged at a predetermined interval on the edge portion on the one side of the photoelectric conversion substrate 1.
The protection circuit 115 is provided between the input / output terminal of the photoelectric conversion element 100 and a processing circuit or the like to protect the circuit from electrostatic breakdown or the like.

The column scanning circuit 102 and the input / output terminal 10
3 and the light receiving pixel 1 arranged on the edge side of the photoelectric conversion substrate 1.
For 00, the light receiving area is smaller and the light receiving amount is smaller than that of the other light receiving pixels, but the output may be corrected so as to keep the output in balance with other light receiving pixels.

FIG. 7 is an enlarged view of a portion where the lead 401 of the flexible wiring board 4 is joined to the input / output terminal 103 on the surface of the photoelectric conversion substrate 1 on which the photoelectric conversion element 100 is formed. (a) is a front view and (b) is a sectional view.

First, the input terminal 103 on the photoelectric conversion substrate 1
The bumps 5 are formed on. The bump 5 may be a so-called stud bump method or a plating method. The leads 401 of the flexible wiring board 4
Are formed by etching copper foil and plated with nickel and gold.

The bumps 5 on the input / output terminals 103 and the leads 401 of the flexible wiring board 4 are, for example,
Connection is made by ultrasonic metal-to-metal bonding. Next, the leads 401 of the joined flexible wiring board 4 are bent at the edges of the photoelectric conversion board 1.

FIG. 8 shows a method of bending the lead 401 and extending it to the back surface side of the photoelectric conversion substrate 1. The photoelectric conversion substrate 1 in which the leads 401 of the flexible wiring substrate 4 are connected to the light receiving pixels 100 via the bumps 5 is held / fixed to the pedestal 17 by means such as vacuum suction, and the input / output terminal joint portion thereof is suppressed. After being lightly held down at 18, the jig 19 is moved horizontally and the leads 401 are bent at an angle of about 90 degrees.

In this embodiment, the input / output terminal 103
The organic insulating layer 105 (polyimide resin layer) was formed in the region from the position of to the edge of the photoelectric conversion substrate 1. this is,
When the lead 401 is bent, the edge portion of the photoelectric conversion substrate 1 and the lead 401 come into contact with each other to cause an electrical short circuit. Further, when the lead 401 is bent, an edge of the photoelectric conversion substrate 1 is mechanically applied. This is to prevent the parts from being lost. Further, a short circuit with the side surface of the photoelectric conversion substrate 1 can be prevented by providing an insulating layer (polyimide layer) on the back surface of the flexible wiring substrate 4. The thickness of this polyimide layer is 25 μm, and a copper foil wiring layer is plated on this to a thickness of about 18 μm. The flexible wiring board 4 here has a total thickness of 43 μm without using an adhesive. Become.

Then, as shown in FIG. 4 and FIG.
The plurality of photoelectric conversion substrates 1 to which the flexible wiring substrate 4 in which 01 is bent are connected are bonded to the light guide portion 2 via the transparent adhesive 6.

FIG. 9 is an enlarged plan view of an arrangement state of pixels between photoelectric conversion substrates. For example, the pixel pitch is 1
If the thickness is 00 μm, the gap between the photoelectric conversion substrates is 8 in consideration of the thickness of the flexible wiring substrate 4 and the bonding accuracy.
The alignment is performed so as to set to 0 μm. Therefore,
As shown in the figure, the pixel pitch is 100-80-140-
Although the irregular pitch is 80-100, the defects of the pixels are not noticeable with the naked eye and the image quality is not deteriorated as compared with the structure in which the pixel lines are not exactly one line.

It is preferable that the adhesive 6 is made of a material having excellent light-transmitting property and elasticity.

FIG. 10 shows a method of adhering the light guide section 2 and the photoelectric conversion substrate 1. After applying the adhesive 15 for temporary fixing to the four corners on the light receiving surface side of the photoelectric conversion substrate 1, with an alignment machine,
Each photoelectric conversion substrate 1 is aligned with a predetermined position of the light guide portion 2, and the temporary fixing adhesive 15 is cured. This is performed for each photoelectric conversion substrate, and after aligning all the photoelectric conversion substrates, a high-viscosity adhesive 16 is used to form a gap between the photoelectric conversion substrates and an edge between the photoelectric conversion substrate 1 and the light guide section 2 which is the outer periphery. Parts are sealed.

Then, the opening 14 is provided without sealing only in one side direction. A sectional view of this state is shown in FIG. After that, when the gap between the light guide portion 2 and the photoelectric conversion substrate 1 is set in a vacuum state in the vacuum chamber, the adhesive 6
The open port 14 is brought into contact with the boat in which the adhesive is stored, and the vacuum state is returned to the atmospheric pressure, so that the pressure difference causes the adhesive 6 to be sucked and filled in the gap as indicated by the chain line. The adhesive 6 and the temporary fixing adhesive 15 are preferably made of the same material or have the same refractive index. In this way, the temporary fixing adhesive 15 is used in advance to form a certain gap between the photoelectric conversion substrate 1 and the light guide member 2, and the photoelectric conversion substrate 1
By adhering to the light guide section 2, the plurality of photoelectric conversion substrates can be aligned quickly and with high accuracy.

After that, the filled adhesive 6 is cured.

Next, as shown in FIG. 11, the flexible wiring board 4 from each photoelectric conversion element is connected to the electronic component 72 including the processing circuit of the base 7. Although the base 7 is newly provided in the present embodiment, the processing circuit and the like can be directly formed on the back surface of the photoelectric conversion substrate 1 by appropriately selecting the material of the photoelectric conversion substrate 1. By doing so, the device can be made thinner, which is preferable.

As the light guide portion 2, an optical fiber plate or the like in which a bundle of optical fibers is collected and cut into a plate shape is preferably used. It can be formed by a simple process as compared with processing in a tapered shape or the like. As the light guide member, it is desirable to use an optical fiber plate or the like in order to guide the light to the photoelectric conversion element without dispersing the light. However, when the light can be dispersed or the dispersion of the light is small, a glass substrate or the like is used. A transparent substrate can be used.

In particular, when used as a radiation image pickup device, a light guide member transparent to visible light and opaque to radiation is used between the phosphor for wavelength conversion of radiation and the photoelectric conversion element. Therefore, it is possible to prevent deterioration and malfunction caused by radiation entering the photoelectric conversion element, which is preferable. The light guide body is made of a material containing lead, and the X-rays that could not be converted into light by the phosphor are shielded by lead, thereby further reducing the influence of the X-rays on the photoelectric conversion element and reducing noise. It is possible to obtain an X-ray image with less noise.

Further, although the light guide member is provided in this embodiment, it is not necessary to provide this. Further, as the phosphor 3, gadolinium sulfide (GdS), cesium iodide (C
sl) or the like may be used. If this phosphor 3 is not provided, it can be used as a photodetector in the visible light band.

(Second Embodiment) FIG. 12 is a sectional view of a radiation image pickup apparatus according to this embodiment. Those having the same functions as those in the first embodiment are designated by the same reference numerals, and detailed description will be omitted. In the present embodiment, a base having a slit is newly provided, and the photoelectric conversion substrate 1 and the base 7 are bonded together with an adhesive 8. Conductors such as leads connected to the input / output terminals of the photoelectric conversion element 100 on the photoelectric conversion substrate 1 via the bumps 5 are connected to the photoelectric conversion substrate 1
Is bent at the end of the photoelectric conversion substrate 1 and extends toward the back surface of the photoelectric conversion substrate 1. Then, the photoelectric conversion substrate 1 having the plurality of photoelectric conversion elements 100 is attached to the base 7 with the adhesive 8.
The base 7 is formed with a bent lead and a slit 70 for passing the flexible circuit board 4 connected to the lead through the back surface of the board.

The radiation passing through the subject becomes information of the radiation intensity difference according to the information of the subject, and the information is converted into the intensity difference of the visible light in the phosphor layer 3 and the intensity difference of the electric signal in the photoelectric conversion substrate 1. . Further, the signal that has been A / D converted by the processing circuit (not shown) of the base 7 is reconstructed by the image processing system to be imaged.

FIG. 13 is a perspective view of the radiation imaging apparatus of this embodiment. A plurality of photoelectric conversion substrates 1 are two-dimensionally arranged on a base 7 provided with slits 70, and the phosphor 3 is arranged thereon.

FIG. 14A shows the photoelectric conversion substrate 1 and the base 7.
It is sectional drawing for demonstrating the adhesion process with. After the photoelectric conversion substrate 1 is aligned with the fixing stage 20 for fixing the photoelectric conversion substrate 1, the photoelectric conversion substrate 1 is sucked and fixed by the vacuum holes provided in the stage 20. For alignment, image alignment can be performed using an alignment mark provided on the photoelectric conversion element by forming a necessary part of the stage 20 with a transparent member.

Next, a necessary amount of adhesive 8 is applied to the back surface of each photoelectric conversion substrate 1, and the adhesive 8 is cured while pressing the base 7 provided with the slit 70. Specifically, a moisture-curable silicone resin or the like may be used for the adhesive 8. The adhesive 8 need not be translucent because it is on the back surface of the light receiving element. FIG. 14B shows a front view of the base 7. As shown in the figure, on the base 7, corresponding to the flexible circuit board 4 extending from the end of the photoelectric conversion substrate 1,
A plurality of slits 70 are formed. Then, as shown in FIG. 15, the electronic component 72 including the processing circuit on the back surface of the base 7 and the flexible wiring board 4 which is passed through the slit 70.
Connect to.

As the base 7, specifically, a printed wiring board made of glass epoxy or the like is used. Alternatively, a ceramic substrate or a glass substrate can be used as a substitute. Further, in order to protect the electronic component 72 from a little radiation that has passed through the phosphor 3, a material containing a radiation shielding material such as Pb may be used.

As shown in FIG. 14B, it is necessary to provide a slit 70 in the base 7, and it is preferable that the holes be easily formed, the weight is light, and the electronic parts can be easily mounted.
Ceramics and glasses are preferably used to satisfy these requirements. Also in the present embodiment, the light guide section may be provided on the photoelectric conversion substrate as in the first embodiment.

(Third Embodiment) FIG. 16 is a sectional view of an image pickup apparatus according to this embodiment, and FIG. 17 is a perspective view. Components having the same functions as those of the first and second embodiments are designated by the same reference numerals and detailed description thereof will be omitted.

In the present embodiment, the input / output terminal 103 of the photoelectric conversion substrate 1 is provided on a surface different from the light receiving surface of the photoelectric conversion element 100 to further reduce the area of the non-light receiving portion of the light receiving surface. That is, almost the entire surface of the photoelectric conversion substrate 1 serves as a light receiving surface, and by arranging a plurality of photoelectric conversion substrates adjacent to each other, the photoelectric conversion substrate 1 or the light receiving pixels formed on the substrate are eliminated and the effective area is large. The area can be reduced.

FIG. 17 is a perspective view of the image pickup device shown in FIG. 16, in which the phosphor 3 and a plurality of photoelectric conversion substrates 1 are bonded via an adhesive 6.
Are attached to each other, and the input / output terminals 103 are formed by etching holes.
Is provided on a surface different from the light receiving surface. An etching hole 106 is provided in each photoelectric conversion substrate 1 and extends from the light receiving surface side of the photoelectric conversion substrate 1 to the back surface side through a conductor such as a lead. Below that, there is a base 7 provided with slits 70 corresponding to the leads exposed on the back surface, and electrodes 700 corresponding to the respective leads are provided.

FIG. 18A is a front view of the photoelectric conversion substrate 1,
A cross-sectional view is shown in FIG.

A light receiving pixel (photoelectric conversion element) 100 two-dimensionally arranged on the silicon substrate 1 and a drive circuit 101 for sequentially driving the two-dimensionally arranged pixel and a wiring connecting the circuit, the pixel and the electrode terminal are formed.

The light receiving pixels 100 are arranged on almost the entire surface of the photoelectric conversion substrate 1, and the pixel pitch is 100 μm. Drive circuits 101 and 102 are arranged between pixels.

FIG. 19 shows a manufacturing process for extracting the input / output terminal 103 from the back surface of the photoelectric conversion substrate 1 by etching.

(Step 1 Backside Polishing) First, as shown in FIG. 19A, the photoelectric conversion substrate 1 is held on a holding substrate with wax or the like, and the backside of the photoelectric conversion device 1 is polished to about 100 μm. The purpose is to reduce the etching process time.

(Step 2 Formation of Etching Mask and Etching) Next, as shown in FIG.
The portion of the Al electrode 107 corresponding to 03 is etched. Since the etching is performed with a strong alkaline solution, the SiO ₂ film 108 which is an alkali resistant material was used as a mask for etching the silicon wafer.

Next, while exposing only the back surface to be etched, and the others, such as silicone rubber, to prevent the invasion of the etching solution, it is immersed in an aqueous solution of tetramethyl hydroxide heated to 80 degrees Celsius, and it takes about 2 hours. Finish the etching. Since the SiO ₂ film is previously formed in front of the electrode, the structure is such that the etching ends with the SiO ₂ film 108 even if overetching is performed.

(Step 3 Formation of Insulating Layer and Formation of Through Hole)
Next, as shown in FIG. 19C, since the etched surface is a silicon semiconductor, the insulating layer 109 is formed in order to prevent leakage from the electrode. SiO ₂ is formed to 0.2 μm by CVD. Here, any material can be used as long as it can prevent leakage, and for example, an organic material such as polyimide may be used.

Next, the hole 106 formed by etching
The insulating layer and the alkali-resistant material film are removed so that they reach the electrode 107. First, after forming a mask with photoresist, through holes are formed by RIE.

(Step 4 Backside Electrode Formation) Next, referring to FIG.
As shown in (d), an aluminum film was formed on the exposed Al electrode 107 and patterned to form an electrode on the back surface of the photoelectric conversion substrate 1 to form a back surface electrode 110. Then, the holding substrate is peeled off.

(Step 5 Bonding External Circuit Board) Next, in step 5 (not shown), the photoelectric conversion boards 1 are arranged adjacent to each other on the base 7. The base 7 uses a ceramic substrate in consideration of the coefficient of thermal expansion and rigidity of the photoelectric conversion substrate 1. The base 7 is provided with an A / D conversion circuit, an electrode 71 for connecting to the photoelectric conversion substrate input / output terminal, and a slit 70 for connecting the photoelectric conversion substrate 1 and the electrode 71 of the base 7 in advance. The slits 70 are aligned with the electrodes of the photoelectric conversion substrate 1 so that the photoelectric conversion substrate 1 is attached to the base 7. Then, the flexible circuit board or the like is extended from the slit through the lead to connect the input / output terminal and the electrode. The distance between the photoelectric conversion substrates was designed to be 80 μm in consideration of misalignment and pixel pitch.

As the adhesive, a silicon resin having a high elastic modulus was used so that stress would not be applied to the photoelectric conversion device. Next, the back electrode 110 provided on the photoelectric conversion substrate 1 and the electrode 71 of the base 7 are connected by wire bonding, and the wire is protected by a sealing material. At the same time, an electronic component 72 including a processing circuit and the like is mounted.

A CMOS element is preferably used as the photoelectric conversion element.

On the light receiving surface, a phosphor 3 (gadolinium sulfide: GdS or cesium iodide Csl) for converting radiation into wavelength light is used.
It is possible to complete the radiation imaging apparatus by stacking the same). Specifically, a phosphor sheet formed by sandwiching GdS or the like with a PET (polyethylene terephthalate) film was used, and the phosphor sheet was attached onto the photoelectric conversion substrate 1 with a translucent adhesive.

Further, as shown in FIG. 20, the radiation not fully absorbed by the phosphor layer 3 enters the photoelectric conversion substrate 1 to prevent characteristic deterioration and malfunction, so that the phosphor layer 3 and the photoelectric conversion substrate 1 are separated from each other. By using a lead glass that allows light to pass through but absorbs radiation, specifically, a radiation shielding member 9 such as a fiber plate, it is possible to provide a more reliable radiation imaging apparatus.

Further, as in the first embodiment, a transparent substrate,
For example, an optical fiber plate or the like can be inserted between the phosphor layer and the light receiving surface of the photoelectric conversion element to improve the light detection efficiency.

(Fourth Embodiment) FIG. 21 is a schematic perspective view of a radiation imaging apparatus of this embodiment, and FIGS. 22 (a) and 22 (b).
22A is a cross-sectional view showing the configuration of the radiation imaging apparatus, and FIG.
21 is a vertical sectional view taken along the line AA of FIG. 21, and FIG. 22B is a lateral sectional view taken along the line BB of FIG.

In this embodiment, an electrode penetrating the photoelectric conversion substrate 1 is provided and extended to the back surface side, and information detected by the photoelectric conversion substrate is taken out of the sensor by a cable. In FIG. 21, 111 is a radiation image sensor. Further, in FIG. 22, 1 is a CMOS image pickup element substrate which is a kind of image pickup element, 100 is a light receiving pixel portion formed on the CMOS image pickup element substrate 1, and 112 is a CMOS.
A wiring circuit section formed on the image pickup element substrate 1, 40 is a through electrode connected to the wiring circuit section 112, 2 is a FOP for transmitting visible light and the like, 3 is CMOS for radiation such as visible light
A phosphor for converting into an electromagnetic wave that can be detected by the image sensor,
8 is an adhesive that holds and fixes the CMOS image sensor substrate 1 on the base 7, and electrically connects, 113 is a case,
Reference numeral 114 is a cable for drawing an electric signal to the outside of the case. An anisotropic conductive adhesive is preferably used as the adhesive. Next, a process of processing the CMOS image pickup device substrate 1 having the above structure will be described with reference to FIGS. Figure 2
3 (a), (c) to (e) are cross-sectional views showing each step, and FIG.
3B is a plan view of the semiconductor wafer shown in FIG.

First, as shown in FIGS. 23A and 23B, a light receiving pixel portion 91a, a driving circuit and an output processing circuit (not shown), a wiring circuit 91b, and the like are formed on a semiconductor wafer 91 by a normal semiconductor. It is formed by a process.

Next, as shown in FIG. 23C, a non-penetrating deep hole 92 is formed in the wiring circuit portion 91 by anisotropic etching or the like, and the insulating layer is connected to the inner surface of the deep hole and the wiring circuit portion 91. Deposit a conductive layer.

After that, as shown in FIG. 23D, etching is performed from the back surface 93 side of the semiconductor wafer 91 until the conductive layer connected to the wiring circuit section 91 is exposed to form a through electrode 94.

Finally, as shown in FIG. 23E, dicing is performed to a predetermined chip size indicated by a dicing line 95 indicated by a chain line in the figure.

By mounting the CMOS image pickup device thus obtained in a dental radiation image pickup apparatus, the non-effective display area of the sensor outer peripheral portion is remarkably small and small as compared with the conventional image pickup device. An integrated sensor can be provided.

The manufactured radiation imaging apparatus 200 is shown in FIG.
4 can be used as the radiation image sensor 82 of the radiation imaging system, and as described above, the X-rays from the X-ray source 80 that have passed through the tooth portion 81 to be diagnosed are loaded behind the intraoral tooth. Dental X-ray image sensor 82
(X-ray image sensor 10). As shown in FIG. 22, the incident radiation is wavelength-converted into visible light by the phosphor 3,
The electric signal projected on the light receiving pixel portion 2a of the CMOS image pickup device through the FOP (fiber optical plate) 4 and processed by the peripheral circuit portion or the like is controlled through the wiring circuit portion 2b, the through electrode 3 and the cable 9. It is transmitted to the device 83. AD conversion and image processing are performed in the control device 83, and the monitor display 84 or the printer 85
To display the tooth image. As a result, dental treatment can be carried out.

(Fifth Embodiment) FIG. 25 is a conceptual diagram of an image processing system of the present invention. In particular, taking X-rays as an example, an X-ray image of a subject is sent from the radiation image pickup apparatus, which is the image pickup apparatus of each of the above-described embodiments, to the image processor 402, and image processing such as contrast enhancement and color classification is performed. After that, it is displayed on the display 401. Further, in order to take an X-ray image by changing the angle, X-rays are generated again from the X-ray generator 403 according to an instruction from the image processor. With such a system, it can be suitably used in photographing a narrow area such as diagnosis of the back teeth and the like, and moving image photographing.

[0078]

According to the present invention described above, it is possible to provide a radiation imaging apparatus such as an X-ray which has both high resolution performance such as a moving image, a wide sensor effective area, downsizing of the apparatus, and cost reduction. You can

Further, in an image processing system using these, for example, in an X-ray imaging system for teeth, the non-imageable region is as small as possible (the effective area utilization rate is high), and the sensor is not used when the X-ray image sensor is inserted into the oral cavity. The miniaturization can reduce the burden on the patient.

[Brief description of drawings]

FIG. 1 is a sectional view of a conventional photoelectric conversion device using a tapered optical fiber.

FIG. 2 Conventional X using an image intensifier
Block diagram of X-ray video system

FIG. 3 is a plan view and a sectional view of a conventional X-ray image sensor.

FIG. 4 is a sectional view of the radiation imaging apparatus according to the first embodiment.

FIG. 5 is a perspective view of a photoelectric conversion substrate used in the image pickup apparatus according to the first embodiment.

FIG. 6 is a plan view of a corner portion of a photoelectric conversion substrate.

FIG. 7 is an enlarged front view and cross-sectional view of a portion of the input / output terminal on the surface of the photoelectric conversion substrate on which the photoelectric conversion element is formed, to which the lead of the flexible wiring substrate is joined.

FIG. 8 is a cross-sectional view for explaining a method of bending a lead and extending it to the back surface side of a photoelectric conversion element.

FIG. 9 is an enlarged plan view of a pixel array between photoelectric conversion substrates.

FIG. 10 is a cross-sectional view and a plan view for explaining a method of adhering the light guide section and the photoelectric conversion substrate.

FIG. 11 is a cross-sectional view showing a state in which a flexible wiring board from each photoelectric conversion element is connected to a base.

FIG. 12 is a sectional view of the radiation imaging apparatus according to the second embodiment.

FIG. 13 is a perspective view of the radiation imaging apparatus according to the second embodiment.

14A and 14B are a cross-sectional view and a plan view for explaining a bonding process between a photoelectric conversion substrate and a base.

FIG. 15 is a cross-sectional view showing a state in which a flexible wiring board is passed through a slit and connected to electronic components on the back surface of the base.

FIG. 16 is a sectional view of the radiation imaging apparatus according to the third embodiment.

FIG. 17 is a perspective view of the radiation imaging apparatus according to the third embodiment.

FIG. 18 is a plan view and a sectional view of a photoelectric conversion plate.

FIG. 19 is a manufacturing process diagram for taking out the input / output terminals from the back surface of the photoelectric conversion substrate.

FIG. 20 is a cross-sectional view of the radiation imaging apparatus according to the third embodiment including a radiation shielding member.

FIG. 21 is a perspective view of the radiation imaging apparatus according to the fourth embodiment.

FIG. 22 is a sectional view of the radiation imaging apparatus according to the fourth embodiment.

FIG. 23 is a process drawing of a CMOS image sensor substrate.

FIG. 24 is a conceptual diagram of a radiation imaging system of the present invention.

FIG. 25 is a conceptual diagram of an image processing system of the present invention.

[Explanation of symbols]

1 Photoelectric conversion element substrate 2 Light guide 3 Phosphor layer 4 Flexible circuit board 5 bumps 6,8 adhesive 7 base 70 slits 72 Electronic components 100 photoelectric conversion element 103 I / O terminal 106 etching hole 700 electrodes

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ identification code FI theme code (reference) H04N 7/18 H01L 27/14 KD (31) Priority claim number Japanese Patent Application 2000-240185 (P2000-240185) (32) Priority date August 8, 2000 (August 2000) (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 2001-182222 (P2001-182222) (32) Priority date June 15, 2001 (June 15, 2001) (33) Country claiming priority Japan (JP) (72) Inventor Osamu Yuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Kenji Kajiwara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Noriyuki Kaifu 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Invention Tetsunobu Mitsuchi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yoshinori Shimamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. F-term (reference) 2G088 EE01 FF02 FF04 FF05 FF06 GG19 JJ05 JJ33 4M118 AA10 AB01 BA04 BA14 CA02 CB11 EA20 FA06 GA10 HA05 HA09 HA12 HA21 HA23 HA25 HA26 HA31 HA33 5C024 AX12 AX16 BX02 GY31 5C054 AA01 AA07 CA02 CC02 HA12

Claims (20)

[Claims] 1. An imaging device having a plurality of photoelectric conversion elements and a plurality of photoelectric conversion substrates on which input / output terminals connected to the photoelectric conversion elements are arranged, wherein the leads connected to the input / output terminals are An image pickup device, characterized in that it extends from a gap between photoelectric conversion substrates to the side opposite to the light receiving surface. 2. The flexible circuit board according to claim 1, further comprising a flexible circuit board connected to the input / output terminal through the lead, and the flexible circuit board controls the input / output terminal and the photoelectric conversion element, or An image pickup device, which is connected to a circuit for processing information from the photoelectric conversion element. 3. The imaging device according to claim 2, further comprising a base, and the circuit is formed on the base. 4. The image pickup device according to claim 3, wherein the base has a slit, and a lead connected to the flexible circuit board extends from the slit and is connected to the circuit. . 5. The image pickup device according to claim 1, wherein the photoelectric conversion element has a CMOS structure. 6. The light transmissive substrate and the photoelectric conversion substrate according to claim 1, further comprising a light transmissive substrate such that the light transmissive substrate and a light receiving surface of the photoelectric conversion element face each other. An imaging device characterized by being provided. 7. The image pickup device according to claim 6, wherein the transparent substrate is an optical fiber plate. 8. A radiation imaging apparatus, comprising: the imaging apparatus according to claim 1; and a wavelength converter on the light-receiving surface side of the photoelectric conversion substrate of the imaging apparatus. 9. An imaging device having a plurality of photoelectric conversion substrates on which a plurality of photoelectric conversion elements are arranged, wherein input / output terminals are connected to the photoelectric conversion elements, and the input / output terminals are connected to the photoelectric conversion substrate. An image pickup device, which is provided on a surface different from a surface on which the photoelectric conversion element is provided. 10. The flexible circuit board according to claim 9, further comprising a lead connected to the input / output terminal via a lead, and the flexible circuit board processes information from the input / output terminal and the photoelectric conversion element. An image pickup apparatus, which is connected to a circuit for controlling the photoelectric conversion element. 11. The image pickup device according to claim 10, further comprising a base, and the circuit is formed on the base. 12. The image pickup device according to claim 11, wherein the base has a slit, and a lead connected to the flexible circuit board extends from the slit and is connected to the circuit. . 13. The image pickup device according to claim 9, wherein the photoelectric conversion element has a CMOS structure. 14. The light transmissive substrate and the photoelectric conversion substrate according to claim 9, further comprising a light transmissive substrate such that the light transmissive substrate and a light receiving surface of the photoelectric conversion element face each other. An imaging device characterized by being fluttered. 15. The imaging device according to claim 14, wherein the translucent substrate is an optical fiber plate. 16. A radiation imaging apparatus, comprising: the imaging apparatus according to claim 9; and a wavelength converter on the light-receiving surface side of the photoelectric conversion substrate of the imaging apparatus. 17. The image pickup apparatus according to claim 1, image processing means for performing image processing on a signal from the image pickup apparatus, recording means for recording a signal from the image processing means, and the image processing. An image processing system comprising: display means for displaying a signal from the means; and electric transmission means for transmitting the signal from the image processing means. 18. The radiation image processing system according to claim 17, further comprising a radiation generation source, and a wavelength converter provided on a radiation incidence side of the imaging device. 19. The image pickup apparatus according to claim 9, an image processing unit for image-processing a signal from the radiation image pickup apparatus, a recording unit for recording a signal from the image processing unit, and an image processing unit. An image processing system comprising: display means for displaying a signal; and electric transmission means for transmitting a signal from the image processing means. 20. The image processing system according to claim 19, further comprising a radiation generation source, wherein a wavelength converter is provided on a radiation incident side of the imaging device.