JP2003172782A - Radiogram imaging device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a miniaturizable radiogram imaging device without complicating a manufacturing process even when a constitution using no fiber optical plate is adopted. <P>SOLUTION: An X-ray shielding member 21 is disposed in front of a CCD chip 3 in the X-ray incidence direction and fixed adhesively to a base 2. On the X-ray shielding member 21, an opening part 22 for inputting an X-ray toward a light receiving part 5 is provided on the position corresponding to the light receiving part 5 of the CCD chip 3. The opening part 22 is formed on the furthermore inside than a part positioned in front of the outside region of the light receiving part 5 of the CCD chip 3, a bonding wire 16 and an electrode pad 14 in the X-ray incidence direction. A scintillator 31 is formed elongatively on the surface of the light receiving part 5 in the state where the X-ray shielding member 21 is disposed in front of the CCD chip 3 in the X-ray incidence direction. A protective film 32 is coated on the surface of the scintillator 31. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray image pickup device for picking up an X-ray image and a method for manufacturing the same.

[0002]

2. Description of the Related Art As this type of X-ray image pickup device, for example, one disclosed in Japanese Patent Laid-Open No. 2000-28735 is known. This X-ray image pickup device includes a fiber optical plate in which a scintillator for converting X-rays into light is grown on the X-ray incident side, and a semiconductor image sensor optically connected to the X-ray emission side of the fiber optical plate. Is equipped with. In addition, JP-A-2000-28
In the X-ray image pickup device disclosed in Japanese Patent No. 735,
The frame body made of a metal that shields X-rays blocks the incidence of X-rays on the shift register, the bonding wires, the amplifier array, and the like.

[0003]

[Patent Document 1] Japanese Unexamined Patent Application Publication No.
X configured as disclosed in Japanese Patent Application Publication No. 000-28735
It has been found that the line image pickup device has the following problems. (1) Since the optical connection between the fiber optical plate on which the scintillator is grown and the semiconductor image sensor is made with an adhesive, the adhesive surface between the fiber optical plate and the semiconductor image sensor may be peeled off. There is. The peeled portion of the adhesive surface causes pattern noise on the image captured by the solid-state image sensor. (2) In order for the fiber optical plate to function as an X-ray shielding member, some thickness is required,
This becomes a factor that hinders the miniaturization of the X-ray image pickup device. (3) Usually, in the fiber optical plate, the semiconductor image sensor is arranged on a base (package), and after electrically connecting by wire bonding, it is bonded to the semiconductor image sensor. Therefore, it is necessary to position and bond the fiber optical plate to the light receiving portion of the semiconductor image sensor so as not to cut the bonding wire, which complicates the bonding process to the semiconductor image sensor.

On the other hand, as a constitution for solving these problems, without using a fiber optical plate,
A scintillator may be grown on the surface of the light receiving portion of the semiconductor image sensor. However, when growing the scintillator on the surface of the light receiving portion of the semiconductor image sensor, a mask is required to grow the scintillator in a desired region of the light receiving portion of the semiconductor image sensor. For this reason, after the mask is arranged at an appropriate position with respect to the light receiving portion of the semiconductor image sensor to grow the scintillator, the mask is removed and the semiconductor image sensor is assembled, which is a manufacturing process of the X-ray image pickup device. Becomes complicated.

The present invention has been made in view of the above-mentioned points. Even in the case of adopting a configuration that does not use a fiber optical plate, the manufacturing process does not become complicated, and the X-ray image pickup apparatus is downsized. It is an object of the present invention to provide an X-ray image pickup device and a method for manufacturing the same.

[0006]

An X-ray image pickup device according to the present invention is provided with a solid-state image pickup element having a light-receiving portion, and is arranged in front of the solid-state image pickup element in the X-ray incident direction, and at a position corresponding to the light-receiving portion. An X-ray shielding member provided with an opening, and a scintillator grown on the surface of the light receiving unit in a state where the X-ray shielding member is arranged in front of the solid-state image sensor in the X-ray incident direction are provided. It is characterized by that.

Since the X-ray image pickup device according to the present invention is provided with the X-ray shield member, it is possible to prevent the portion of the solid-state image pickup element located outside the light receiving portion from being irradiated with X-rays. The X-ray shielding member functions as a mask member for growing a scintillator on the surface of the light receiving portion of the solid-state image sensor, and the scintillator has the X-ray shielding member disposed in front of the solid-state image sensor in the X-ray incident direction. Is grown in the state of being. Thereby, the scintillator can be surely grown at an appropriate position on the surface of the light receiving portion of the solid-state image sensor. Further, since the scintillator can be formed in a state in which the X-ray shielding member is arranged in front of the solid-state imaging device in the X-ray incident direction, it is possible to prevent the manufacturing process from becoming complicated.

Further, in the X-ray image pickup device according to the present invention, since the fiber optical plate provided in the conventional technique is not used, the X-ray image pickup device can be reduced in size and cost.

Further, it is preferable to further include a wiring arranged outside the light receiving portion when viewed from the X-ray incident direction and for taking out a signal output of the solid-state image pickup device, and a protective resin covering the wiring. As described above, the scintillator is attached to the wiring by further including the wiring arranged outside the light receiving portion when viewed from the X-ray incident direction and for taking out the signal output of the solid-state imaging device, and the protective resin that covers the wiring. It is possible to prevent the deterioration of the wiring. In addition, it is possible to effectively protect the wiring from short circuit and disconnection.

Further, it is preferable to further include an electrically insulating organic film formed so as to cover the scintillator. As described above, by further including the electrically insulating organic film formed so as to cover the scintillator, the scintillator and the light receiving section of the solid-state imaging device can be reliably brought into close contact, and the scintillator can be prevented from peeling off. it can. As a result, it is possible to prevent the characteristics of the solid-state image sensor from being deteriorated by peeling off the scintillator that has once adhered.

In the method for manufacturing an X-ray image pickup device according to the present invention, an opening is provided at a position corresponding to the light-receiving section in front of the X-ray incident direction of the solid-state image pickup element having the light-receiving section in which a plurality of photoelectric conversion elements are arranged. The present invention is characterized in that the scintillator is allowed to grow on the surface of the light receiving section with the X-ray shielding member provided and the X-ray shielding member disposed in front of the solid-state imaging device in the X-ray incident direction.

In the method of manufacturing an X-ray image pickup device according to the present invention, X is formed in a portion located outside the light receiving portion of the solid-state image pickup element.
The X-ray shielding member for preventing the irradiation of the X-ray functions as a mask member for growing the scintillator on the surface of the light receiving portion of the solid-state imaging device, and the scintillator has the X-ray shielding member for the X-ray of the solid-state imaging device. It is grown in a state of being arranged forward of the line incident direction. Thereby, the scintillator can be surely grown at an appropriate position on the surface of the light receiving portion of the solid-state image sensor. Further, since the scintillator can be formed in a state in which the X-ray shielding member is arranged in front of the solid-state imaging device in the X-ray incident direction, it is possible to prevent the manufacturing process from becoming complicated.

Further, in the method of manufacturing the X-ray image pickup device according to the present invention, the X-ray image pickup device is manufactured without using the fiber optical plate provided in the conventional technique, so that it is possible to reduce the size and size. It is possible to realize a method of manufacturing an X-ray image pickup device, which enables cost reduction.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of an X-ray image pickup device and a manufacturing method thereof according to the present invention will be described below in detail with reference to the drawings. In the description, the same elements or elements having the same function will be denoted by the same reference symbols, without redundant description.

(First Embodiment) First, a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic diagram for explaining the cross-sectional structure of the X-ray image pickup device according to the first embodiment. As shown in FIG. 1, an X-ray image pickup apparatus 1
Includes a ceramic base 2 as a container (package) and a CCD chip 3 as a solid-state image sensor. The base 2 accommodates the CCD chip 3, and a recess 4 extending in a predetermined direction of the base 2 is formed in the center thereof. The CCD chip 3 is placed on the bottom of the recess 4 and is fixed to the recess 4 (base 2).

The CCD chip 3 has a light receiving section 5 in which a plurality of photoelectric conversion elements are arranged. The CCD chip 3 has
As shown in FIG. 2, an FFT CCD is formed, and a vertical shift register portion 6 and a horizontal shift register portion 7 are provided. Here, the vertical shift register portion 6 in FIG. 2 corresponds to the light receiving portion 5.
The vertical shift register portion 6 includes a light receiving area 8, an optical black area 9, and an isolation area 10. The light receiving area 8 is formed by arranging a plurality of photoelectric conversion elements (pixels) two-dimensionally. The optical black area 9 is located outside the light receiving area 8, and a photoelectric conversion element configured so that light does not enter is arranged so as to surround the light receiving area 8. Also, the isolation area 10
In order to electrically separate the light receiving area 8 and the optical black area 9, it is arranged between the light receiving area 8 and the optical black area 9.

The input section 11 is a vertical shift register section 6
And for injecting an electric signal into the horizontal shift register portion 7. The charges accumulated in the potential well by light reception / imaging during the charge accumulation period are sequentially transferred during the charge transfer period by the vertical shift register portion 6 and the horizontal shift register portion 7 to become a time series signal. The transferred charges are converted into a voltage by the output unit 12 and output as an image signal.

The vertical shift register portion 6 (each photoelectric conversion element), the horizontal shift register portion 7, the input section 11, and the output section 12 are connected by a wiring on a chip (not shown) to C.
It is electrically connected to the corresponding electrode pad among the electrode pads 13 arranged at the end portion of the CD chip 3 (outside the light receiving portion 5).

A plurality of electrode pads 14 are arranged outside the portion of the recess 4 where the CCD chip 3 is fixed. These electrode pads are electrically connected to electrode terminals 15 for external connection arranged on the back surface of the base 2 and internal wiring (not shown) penetrating the base 2.

The CCD chip 3 is mounted on the base 2 so that the corresponding electrode pads 13 and 14 are close to each other, and the corresponding electrode pads 13 and 14 are electrically connected by a bonding wire 16 (wiring). Connected to each other. The bonding wire 16 is for taking out the signal output of the light receiving portion 5 of the CCD chip 3 (each photoelectric conversion element of the vertical shift register portion 6), and is arranged outside the light receiving portion 5 of the CCD chip 3. The electrode pad 13 is
Bonding wire 16, electrode pad 14, internal wiring,
Also, it is electrically connected to the electrode terminal 15.

The X-ray image pickup device 1 is provided with a plate-shaped X-ray shield member 21. The X-ray shield member 21 is disposed in front of the CCD chip 3 in the X-ray incident direction, and is bonded and fixed to the step portion 18 formed on the base 2. X-ray shielding member 2
No. 1 is made of a material that does not easily transmit X-rays, such as CuW. The X-ray shielding member 21 includes a light receiving portion 5 of the CCD chip 3.
At a position corresponding to (vertical shift register portion 6), an opening portion 22 for allowing X-rays to enter the light receiving portion 5 is provided.

The X-ray shielding member 21 is a region outside the light receiving portion 5 (vertical shift register portion 6) of the CCD chip 3 (horizontal shift register portion 7, input portion 11, output portion 12, and electrode pad 13), bonding wire. 16 and the front of the electrode pad 14 in the X-ray incident direction are shielded to prevent X-rays from entering these portions. The opening 22 is CC
It is formed inside the outer region of the light receiving portion 5 of the D chip 3, the bonding wire 16, and the portion located forward of the electrode pad 14 in the X-ray incident direction. In this way, the X-ray shielding member 21 is provided on the outside area of the light receiving portion 5 of the CCD chip 3, the bonding wire 16, and the electrode pad 1.
By preventing X-rays from being incident on 4, it is possible to reduce noise generation and CCD deterioration due to X-ray irradiation. It should be noted that the shape and size of the opening 22 are such that the Csl vapor circulates to the back surface side of the X-ray shielding member 21 in the step of forming the scintillator 31 described later, and the light receiving portion 5 (vertical shift register portion 6 of the CCD chip 3 ) Outside region (horizontal shift register portion 7, input portion 11, output portion 12, and electrode pad 13), bonding wire 16, and electrode pad 14 are set so as not to be attached.

Further, the X-ray image pickup device 1 is provided with a scintillator 31 for converting incident X-rays into light in a wavelength band in which the photoelectric conversion element of the light receiving section 5 has sensitivity. The scintillator 31 is grown and formed on the surface of the light receiving portion 5 (vertical shift register portion 6) in a state where the X-ray shielding member 21 is arranged in front of the CCD chip 3 in the X-ray incident direction.
The scintillator 31 is made of columnar crystals such as CsI and NaI, or powdery crystals such as Gd ₂ O ₂ S. Further, since the scintillator 31 is grown with the X-ray shielding member 21 disposed in front of the CCD chip 3 in the X-ray incident direction,
It is also grown and formed on the surface of the X-ray shielding member 21 which is the X-ray incident side.

A protective film 32 is formed on the surface of the scintillator 31.
Is coated. The protective film 32 is transparent to X-rays and blocks water vapor.
From the first side, an electrically insulating first organic film 33 and a reflective thin film 3
4. An electrically insulating second organic film 35 is laminated.

The first organic film 33 and the second organic film 35
Prevents the scintillator 31 from coming into contact with the air, thereby preventing the luminous efficiency from deteriorating due to deliquescent. The first organic film 33 and the second organic film 35 have high X-ray transparency and extremely low water vapor and gas permeation, polyparaxylene (manufactured by ThreeBond, trade name Parylene), polyparachloroxylylene ( It is made of a xylene resin such as Parylene C) manufactured by the same company, and is formed by using a CVD (chemical vapor deposition) method or the like. These parylene coating films have extremely low water vapor and gas permeation, high water repellency and chemical resistance, and even thin films have excellent electrical insulation and are transparent to radiation and visible light. It has excellent characteristics suitable for the membranes 33 and 35.

The reflective thin film 34 reflects the light generated by the scintillator 31 not to the CCD chip 3 side but to the X-ray incident side, thereby reducing the loss of the light emission amount and increasing the detection sensitivity of the detector. Can be increased. The reflective thin film 34 can also block direct light from the outside.
As the reflection thin film 34, a metal thin film such as gold, silver or aluminum can be used.

As shown in FIG. 1, the base 2 has a recess.
A window member 17 for sealing the portion 4 is adhesively fixed.
Is the window material 17 a material that blocks visible light and transmits X-rays?
Consists of Be (beryllium), Al (aluminum),
C (carbon), Lexan ^TM(Compound of C, H, O)
Are used.

Next, a method for manufacturing the X-ray image pickup device 1 having the above-described structure will be described with reference to FIGS. 3 to 7 are schematic diagrams for explaining the method of manufacturing the X-ray image pickup device according to the first embodiment.

First, as shown in FIG. 3, the CCD chip 3 is fixed to the base 2 with an adhesive (for example, an epoxy resin adhesive). At this time, the CCD chip 3 is placed on the bottom of the recess 4 with the surface of the light receiving unit 5 facing the X-ray incident side. Then, the corresponding electrode pad 13 and electrode pad 14 are connected to each other by the bonding wire 1.
Connect electrically at 6.

When the connection by the bonding wire 16 is completed, the X-ray shield member 21 is moved to the X-axis as shown in FIG.
With the opening 22 formed in the line blocking member 21 positioned so as to be positioned in front of the light receiving portion 5 (vertical shift register portion 6) of the CCD chip 3 in the X-ray incident direction, the base 2
Are bonded and fixed using an adhesive (for example, an epoxy resin adhesive). At this time, the X-ray shield member 21 is a CCD
The area outside the light receiving portion 5 of the chip 3 (the horizontal shift register portion 7, the input portion 11, the output portion 12, and the electrode pad 1
3), the front of the bonding wire 16 and the electrode pad 14 in the X-ray incident direction is shielded.

Next, as shown in FIG. 5, Csl doped with Tl is grown as a columnar crystal having a thickness of about 200 μm by a vacuum vapor deposition method to form a scintillator 31.
To form. At this time, the Csl vapor is absorbed by the X-ray shielding member 2
Through the opening 22 of 1 into the recess 4
The X-ray shielding member 21 functions as a mask member for growing and forming the scintillator 31, and the scintillator 31 is provided on the surface of the light receiving portion 5 (vertical shift register portion 6) of the CCD chip 3 corresponding to the position of the opening 22. Will be formed. Therefore, the scintillator 31 is provided on the outside area (the horizontal shift register portion 7, the input portion 11, the output portion 12, and the electrode pad 13) of the light receiving portion 5 of the CCD chip 3,
It does not adhere to the bonding wire 16 and the electrode pad 14. The scintillator 31 is also grown and formed on the surface of the X-ray shielding member 21 on the X-ray incident side.

Csl has a high hygroscopic property, and if left exposed, it absorbs water vapor in the air and dissolves.
To protect the CCD, as shown in FIG. 6, a CCD having a scintillator 31 formed by a CVD (chemical vapor deposition) method.
The first organic film 33 is formed by including the chip 3, the X-ray shielding member 21, and the like, and wrapping the entire recess 4 with parylene having a thickness of 10 μm.

Specifically, coating is performed by vapor deposition in a vacuum as in the case of vacuum vapor deposition of metals, in which the raw material diparaxylylene monomer is thermally decomposed and the product is an organic solvent such as toluene or benzene. In the process of quenching inside to obtain diparaxylylene called dimer, the step of thermally decomposing this dimer to generate a stable radical paraxylylene gas, the generated gas is adsorbed on the material and polymerized to a molecular weight of about 500,000. Of the polyparaxylylene film.

Although there is a gap between the columnar crystals of Csl,
Parylene enters the narrow gap to some extent, so the first
The organic film 33 of 3 adheres to the scintillator 31 and seals the scintillator 31. Further, the first organic film 33 is
The area outside the light receiving portion 5 of the CCD chip 3 (the horizontal shift register portion 7, the input portion 11, the output portion 12, and the electrode pad 13), the bonding wire 16, and the electrode pad 14.
It is also formed on and covers these. By this parylene coating, it is possible to form a precision thin film coating having a uniform thickness on the surface of the scintillator 31 having irregularities. Further, the CVD formation of parylene has a lower degree of vacuum than that at the time of vapor deposition of metal and can be performed at room temperature, so that it is easy to process.

Subsequently, as shown in FIG. 7, a reflection thin film 34 is formed by laminating an Al film having a thickness of 0.15 μm on the surface of the first organic film 33 on the incident surface side by vapor deposition. At this time, like the Csl vapor at the time of forming the scintillator 31, the Al vapor enters the recess 4 through the opening 22 of the X-ray shielding member 21, and thus the X-ray shielding member 21.
Serves as a mask member for forming the reflective thin film 34, and the reflective thin film 34 is formed on the first organic film 33 immediately above the scintillator 31 formed in the light receiving portion 5 (vertical shift register portion 6) of the CCD chip 3. Will be formed. The reflection thin film 34 is also formed on the surface of the X-ray shielding member 21 on the X-ray incident side.

At the time of vapor deposition, even if the X-ray shielding member 21 is arranged, the Al vapor may slightly reach the back side of the X-ray shielding member 21. However, CC
An area outside the light receiving portion 5 of the D chip 3 (horizontal shift register portion 7, input portion 11, output portion 12, and electrode pad 1
3), the bonding wire 16 and the electrode pad 14 are covered with the first organic film 33, so that the reflective thin film 34
Is not directly formed on these parts, and the electrode pad 13 and the bonding wire 1 by the reflective thin film 34 are formed.
6. Short circuit of the electrode pad 14 can be effectively prevented.

Then, the second organic film 35 is formed by coating the surface of the whole substrate with parylene to a thickness of 10 μm by the CVD method again (see FIG. 7). This second organic film 35
Is for preventing dirt, peeling, and deterioration due to oxidation of the reflective thin film 34 due to handling and the like. Thus, the first organic film 33, the reflective thin film 34, the second organic film 3
A protective film 32 formed by stacking 5 is formed. Finally,
The window material 17 is adhered and fixed to the base 2 with an adhesive (for example, an epoxy resin adhesive), whereby the X-ray image pickup device 1 shown in FIG. 1 is obtained.

Next, the operation of the X-ray image pickup device 1 will be described. The X-rays that have passed through the window material 17 and are incident on the organic film 33,
35, the scintillator 31 is transmitted through all of the reflective thin film 34.
Reach This X-ray is absorbed by the scintillator 31,
Light is emitted in proportion to the amount of X-rays. Of the emitted light, the light that has gone backward in the X-ray incident direction is the first organic film 3
3 and is reflected by the reflective thin film 34. For this reason,
Almost all of the light generated by the scintillator 31 is a CCD
The light is incident on the light receiving portion 5 (vertical shift register portion 6) of the chip 3. As a result, efficient and highly sensitive measurement becomes possible.

In the vertical shift register portion 6 (each photoelectric conversion element), an electric signal corresponding to the amount of visible light is generated by photoelectric conversion and accumulated for a certain period of time. Since the amount of visible light corresponds to the amount of incident X-rays, that is, the electric signal accumulated in each photoelectric conversion element corresponds to the amount of incident X-rays, and the X-rays An image signal corresponding to the image is obtained. The image signal stored in the photoelectric conversion element is supplied to the electrode pad 13, the bonding wire 16 and the electrode pad 1 from a signal line (not shown).
4. The X-ray image can be displayed by finally outputting sequentially from the electrode terminal 15 via the internal wiring to transfer it to the outside and processing it.

As described above, according to the first embodiment, X
The X-ray shielding member 21 functions as a mask member for growing the scintillator 31 on the surface of the light receiving unit 5 (vertical shift register portion 6) of the CCD chip 3, and the X-ray shielding member 21 of the scintillator 31 has the X-ray shielding member 21. Are grown in a state of being arranged in front of the X-ray incidence direction. This allows
It is possible to surely grow the scintillator 31 at an appropriate position on the surface of the light receiving unit 5 of the CCD chip 3. Also,
Since the scintillator 31 can be formed in a state in which the X-ray shielding member 21 is arranged in front of the CCD chip 3 in the X-ray incident direction, it is possible to prevent the manufacturing process from becoming complicated.

Further, the X-ray image pickup apparatus 1 of the first embodiment.
In the above, since the fiber optical plate provided in the conventional technique is not used, the X-ray image pickup device 1 can be downsized.

Further, the X-ray image pickup apparatus 1 of the first embodiment.
In the above, by further including the electrically insulating organic films 33 and 35 formed so as to cover the scintillator 31, the scintillator 31 and the light receiving portion 5 (vertical shift register portion 6) of the CCD chip 3 are surely brought into close contact with each other. It is possible to prevent the scintillator 31 from peeling off. As a result, it is possible to prevent the characteristic of the CCD chip 3 from being deteriorated by peeling off the scintillator 31 attached once.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 8 is a schematic diagram for explaining the cross-sectional structure of the X-ray image pickup apparatus according to the second embodiment.

In the X-ray image pickup device 51 of the second embodiment, as shown in FIG. 8, the protective resin 6 covering and covering the electrode pads 13 and 14 and the bonding wire 16.
1 is provided. The protective resin 61 is a resin having good adhesiveness to the protective film 32 (organic film 33) described above, for example, WORLD ROCK No.801-SET2 (70,000cP made by Kyoritsu Chemical Industry Co., Ltd., which is an acrylic adhesive. Type) is preferably used. The protective film 32 (organic films 33, 35) is
It will be formed on the surface of the protective resin 61.

The method of manufacturing the X-ray image pickup device 51 will be described. First, the CCD chip 3 is adhesively fixed to the base 2 and the corresponding electrode pads 13 and 14 are electrically connected by the bonding wires 16. After that, a protective resin 61 is formed by applying a resin so as to wrap the electrode pads 13 and 14 and the bonding wire 16 and curing the resin. As a result, the bonding wire 16 is encapsulated in the resin and protected, so that the bonding wire 16 is protected.
Since the adhesive strength and mechanical strength of the bonding wire 16 are increased, it is possible to effectively prevent damage such as disconnection and short circuit of the bonding wire 16 in the subsequent manufacturing process and use.

After that, the X-ray shielding member 21 is positioned so that the opening 22 formed in the X-ray shielding member 21 is located in front of the light receiving portion 5 (vertical shift register portion) of the CCD chip 3 in the X-ray incident direction. In this state, the base 2 is bonded and fixed using an adhesive (for example, an epoxy resin adhesive). Then, similarly to the first embodiment, the X-ray shielding member 2
1 is used as a mask member to grow and form a scintillator 31, and a protective film 32 (first organic film 33, reflective thin film 34, second organic film 35) is further formed.

As described above, according to the second embodiment, the X-ray shielding member 21 is connected to the CC as in the first embodiment described above.
By making it function as a mask member for growing the scintillator 31 on the surface of the light receiving portion 5 (vertical shift register portion 6) of the D chip 3, it is possible to prevent the manufacturing process of the X-ray image pickup device 51 from becoming complicated. it can. Further, since the fiber optical plate provided in the conventional technique is not used, the X-ray image pickup device 51 can be downsized and the cost can be reduced.

Further, the X-ray image pickup device 5 of the second embodiment.
1 includes the protective resin 61 that covers and wraps the electrode pads 13 and 14 and the bonding wire 16, so that the scintillator 31 is prevented from adhering to the electrode pads 13 and 14 and the bonding wire 16, It is possible to prevent the pads 13 and 14 and the bonding wire 16 from being deteriorated.

Further, the X-ray image pickup device 5 of the second embodiment.
1, the protective film 32 (organic films 33, 35) is formed on the surface of the protective resin 61, and the bonding wire 1
Since 6 is further protected, damage to the bonding wire 16 during use can be effectively prevented.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 9 is a schematic diagram for explaining the cross-sectional structure of the X-ray image pickup device according to the third embodiment.

In the X-ray image pickup device 71 of the third embodiment, the backside illuminated CCD chip 8 is used as a solid-state image pickup device.
1 is used. The CCD chip 81 has a thickness of about 300-
It is made of a P-type silicon substrate having a thickness of about 600 μm and is composed of, for example, a P ⁺ layer of silicon and a P epitaxial layer formed thereon. A CCD 82 is formed on the surface of the P epitaxial layer of the CCD chip 81, and at the portion corresponding to the CCD 82 on the opposite side of the P epitaxial layer, a portion of the P ⁺ layer is removed to expose the P epitaxial layer. Thus, the light guide concave portion is formed, and the accumulation layer is formed. Therefore, CCD
The chip 81 is provided with a thinned portion 84 including a CCD 82. The thin portion 84 is about 15
The thickness is about 40 μm.

A wiring board 72 having a contact pad 73 formed on one surface side at the bottom of the recess 4 of the base 2.
Is mounted and fixed to the base 2. CCD chip 8
1 is disposed on the wiring board 72 such that the back surface side of the surface on which the CCD 82 is formed is the light incident surface. As a result, in the CCD chip 81, C of the thin portion 84
The portion on the back surface side of the CD 82 serves as a light receiving portion. The electrode pads (not shown) of the CCD chip 81 are connected to the conductive bumps 7.
4 is electrically connected (bump bonding) to the contact pad 73 of the wiring board 72.

Further, the contact pad 7 of the wiring board 72
3 and the electrode pad 14 of the base 2 are electrically connected by a bonding wire 16. This allows CC
The signal charge obtained in D82 is the electrode pad of the CCD chip 81, the conductive bump 74, the contact pad 73, the bonding wire 16, the electrode pad 14, and the electrode terminal 1.
It is designed to be taken out through 5.

The X-ray image pickup device 71 is the X-ray image pickup device of the first embodiment.
Like the line image pickup device 1, the X-ray shield member 21 is provided. The X-ray shielding member 21 is arranged in front of the CCD chip 81 in the X-ray incident direction and is fixed to the base 2 by adhesion. The X-ray shielding member 21 is provided with an opening 22 at a position corresponding to the thin portion 84 (light receiving portion) of the CCD chip 81 for allowing X-rays to enter the thin portion 84.

The X-ray shielding member 21 is located outside the thin portion 84 of the CCD chip 81 (bevel portion 85, frame portion 8).
6), contact pad 73, bonding wire 1
6. The front of the electrode pad 14 in the X-ray incidence direction is shielded to prevent X-rays from entering these portions. Opening 22
Is formed inside the outer region (bevel portion 85, frame portion 86) of the thin portion 84 of the CCD chip 81, which is located in front of the X-ray incident direction. In this way, the X-ray shielding member 21 prevents X-rays from being incident on the outer region of the thin portion 84 of the CCD chip 81, the contact pad 73, the bonding wire 16, and the electrode pad 14 to prevent noise due to X-ray irradiation. Generation and CCD
Can be reduced. The shape and size of the opening 22 are Csl vapor in the process of forming the scintillator 31 and A in the process of forming the reflective thin film 34.
l Vapor wraps around the back surface of the X-ray shielding member 21 and CC
Outside the thin portion 84 of the D chip 81 (bevel portion 8
5, the frame portion 86), the contact pad 73, the bonding wire 16, and the electrode pad 14 are set so as not to be attached.

The scintillator 31 is grown and formed on the surface of the thin portion 84 (light receiving portion) in a state where the X-ray shielding member 21 is arranged in front of the CCD chip 81 in the X-ray incident direction. The protective film 3 is formed on the surface of the scintillator 31.
2 (first organic film 33, reflective thin film 34, second organic film 3
5) is coated.

Next, a method of manufacturing the X-ray image pickup device 71 having the above-described structure will be described with reference to FIGS. 10 to 14 are schematic diagrams for explaining the method of manufacturing the X-ray image pickup device according to the third embodiment.

First, as shown in FIG. 10, the CCD chip 81 is placed on the wiring board 72 via the conductive bumps 74, and then the wiring board 72 is attached to the base 2 with an adhesive (for example, epoxy resin). System adhesive). At this time, the CCD chip 81 is placed with the back surface side of the surface on which the CCD 82 is formed facing the X-ray incident side.

When the CCD chip 81 is set and fixed, the contact pads 73 of the wiring board 72 and the electrode pads 14 are electrically connected by the bonding wires 16 as shown in FIG. Then, the X-ray shielding member 21 is provided with the opening 22 formed in the X-ray shielding member 21 in the CCD chip 8.
In a state of being positioned so as to be located in front of the thin portion 84 (light receiving portion) 1 of the X-ray incidence direction, it is adhesively fixed to the base 2 using an adhesive (for example, an epoxy resin adhesive).
At this time, the X-ray shielding member 21 is located outside the thin portion 84 of the CCD chip 81 (bevel portion 85, frame portion 8).
6), contact pad 73, bonding wire 1
6. The front of the electrode pad 14 in the X-ray incident direction is shielded.

Next, as shown in FIG. 12, Csl doped with Tl was deposited to a thickness of about 200 μm by a vacuum deposition method.
Scintillator 3 by growing as columnar crystals of
1 is formed. At this time, the Csl vapor enters the recess 4 through the opening 22 of the X-ray shielding member 21, and the X-ray shielding member 21 functions as a mask member for growing and forming the scintillator 31. The scintillator 31 is formed on the surface of the thin portion 84 of the CCD chip 81 corresponding to the position of the opening 22. Therefore, the scintillator 31 does not adhere to the outer region (bevel portion 85, frame portion 86) of the thin portion 84 of the CCD chip 81, the contact pad 73, the bonding wire 16, and the electrode pad 14.

Subsequently, as shown in FIG. 13, CVD
The CCD chip 81 on which the scintillator 31 is formed by the (chemical vapor deposition) method and the entire recessed portion 4 of the base 2 on which the X-ray shielding member 21 is disposed are covered with parylene having a thickness of 10 μm, and the first organic film 33 is formed. To form. This first organic film 3
Reference numeral 3 denotes an outer region (bevel portion 85, frame portion 86) of the thin portion 84 of the CCD chip 81, the contact pad 73,
It is also formed on the bonding wire 16 and the electrode pad 14, and covers these.

Next, as shown in FIG. 14, a reflection thin film 34 is formed by laminating an Al film having a thickness of 0.15 μm on the incident surface side surface of the first organic film 33 by vapor deposition. At this time, like the Csl vapor at the time of forming the scintillator 31, the Al vapor enters the recess 4 through the opening 22 of the X-ray shielding member 21, and thus the X-ray shielding member 21.
Functions as a mask member for forming the reflective thin film 34, and the reflective thin film 34 is formed on the first organic film 33 immediately above the scintillator 31 formed on the thin portion 84 of the CCD chip 81. . And CVD again
By the method, parylene is coated on the entire surface of the substrate to a thickness of 10 μm to form the second organic film 35 (see FIG. 14).
The formation of the first organic film 33, the reflective thin film 34, and the organic film 35 is performed in the same manner as in the first embodiment. Finally, window material 1
The X-ray image pickup device 71 shown in FIG. 9 is obtained by adhesively fixing 7 to the base 2 with an adhesive (for example, an epoxy resin adhesive).

As described above, according to the third embodiment, the X-ray shielding member 21 grows the scintillator 31 on the surface of the thin portion 84 (light receiving portion) of the CCD chip 81, as in the first embodiment. The scintillator 31 functions as a mask member for the X-ray shielding member 21 of the CCD chip 81.
Are grown in a state of being arranged in front of the X-ray incidence direction. As a result, the scintillator 31 can be reliably grown at an appropriate position on the surface of the thin portion 84 of the CCD chip 81. Further, since the scintillator 31 can be formed in a state in which the X-ray shielding member 21 is arranged in front of the CCD chip 81 in the X-ray incident direction, it is possible to prevent the manufacturing process from becoming complicated. Of course, the X-ray image pickup device 71 can be downsized.

Generally, the thin portion 84 of the CCD chip 81 has weak mechanical strength, and it is difficult to optically connect the fiber optical plate having the scintillator to the thin portion 84. However, according to the third embodiment, the scintillator 31 can be easily provided on the thin portion 84 having low mechanical strength.

Further, the X-ray image pickup device 7 of the third embodiment.
In FIG. 1, the scintillator 31 and the reflective thin film 34 are formed only on the thin portion 84 of the CCD chip 81, and particularly, the scintillator 31 and the reflective thin film 34 are formed on the bevel portion 85 of the CCD chip 81. Absent. Thus, the light incident on the bevel portion 85 is multiply reflected between the bevel portion 85 and the reflective thin film 34, and the CCD
It is possible to prevent the light from entering the thin portion 84 of the chip 81.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 15 is a schematic diagram for explaining the cross-sectional structure of the X-ray image pickup device according to the fourth embodiment.

In the X-ray image pickup device 91 of the fourth embodiment, a Peltier element 95 as a cooler for cooling the CCD chip 81 is provided. The Peltier element 95 is
The heat generating portion of the Peltier element 95 is mounted on the bottom of the recess 4 of the base 2 and fixed to the base 2. The wiring board 72 is placed on the upper surface of the heat absorbing portion of the Peltier element 95 located on the side opposite to the heat generating portion, and is fixed to the upper surface of this heat absorbing portion. The heat generating section side of the Peltier element 95 is connected to a power supply section (not shown) for supplying power to the Peltier element 95.

Also in the fourth embodiment, as in the third embodiment, the X-ray shielding member 21 is used as a mask member for growing the scintillator 31 on the surface of the thin portion 84 (light receiving portion) of the CCD chip 81. By making the function, it is possible to prevent the manufacturing process of the X-ray image pickup device 91 from becoming complicated, and it is possible to reduce the size and cost of the X-ray image pickup device 91.

In the first to fourth embodiments, the protective film 32 has the structure in which the reflective thin film 34 is sandwiched between the organic films 33 and 35 made of parylene.
The materials of the first organic film 33 and the second organic film 35 may be different, and when a material such as gold that is resistant to corrosion is used as the reflective thin film 34, the second organic film 35 itself may be used. It may not be provided. Further, the solid-state image pickup device is not limited to the CCD chips 3 and 81, and may be one formed by a photodiode (PD) array made of amorphous silicon and a thin film transistor (TFT), or a MOS type image sensor.

Further, in the third and fourth embodiments, the bonding wire 16 may be covered with a protective resin as in the second embodiment.

[0071]

As described above in detail, according to the present invention, even when the configuration without using the fiber optical plate is adopted, the manufacturing process does not become complicated, and the X-ray image pickup apparatus can be miniaturized. It is possible to provide an X-ray image pickup device and a manufacturing method thereof that can be realized.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a cross-sectional configuration of an X-ray image pickup device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining a configuration of a CCD chip included in the X-ray image pickup device according to the first embodiment of the present invention.

FIG. 3 is a schematic view for explaining the method for manufacturing the X-ray image pickup device according to the first embodiment of the present invention.

FIG. 4 is a schematic view for explaining the method of manufacturing the X-ray image pickup device according to the first embodiment of the present invention.

FIG. 5 is a schematic view for explaining the method for manufacturing the X-ray image pickup device according to the first embodiment of the present invention.

FIG. 6 is a schematic view for explaining the method for manufacturing the X-ray image pickup device according to the first embodiment of the present invention.

FIG. 7 is a schematic view for explaining the method for manufacturing the X-ray image pickup device according to the first embodiment of the present invention.

FIG. 8 is a schematic diagram for explaining a cross-sectional configuration of an X-ray image pickup device according to a second embodiment of the present invention.

FIG. 9 is a schematic diagram for explaining a cross-sectional configuration of an X-ray image pickup device according to a third embodiment of the present invention.

FIG. 10 is a schematic diagram for explaining the method of manufacturing the X-ray image pickup device according to the third embodiment of the present invention.

FIG. 11 is a schematic diagram for explaining the method of manufacturing the X-ray image pickup device according to the third embodiment of the present invention.

FIG. 12 is a schematic view for explaining the method for manufacturing the X-ray image pickup device according to the third embodiment of the present invention.

FIG. 13 is a schematic diagram for explaining the method of manufacturing the X-ray image pickup device according to the third embodiment of the present invention.

FIG. 14 is a schematic diagram for explaining the method of manufacturing the X-ray image pickup device according to the third embodiment of the present invention.

FIG. 15 is a schematic diagram for explaining a cross-sectional configuration of an X-ray image pickup device according to a fourth embodiment of the present invention.

[Explanation of symbols]

1, 51, 71, 91 ... X-ray image pickup device, 2 ... Base 3
... CCD chip, 5 ... Light receiving part, 16 ... Bonding wire, 21 ... X-ray shielding member, 22 ... Opening part, 31 ... Scintillator, 32 ... Protective film, 33 ... First organic film, 34 ... Reflective thin film, 35 ... Second organic film, 61 ... Protective resin, 81 ...
CCD chip, 82 ... CCD, 84 ... Thin portion, 95 ...
Peltier element.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 5/32 H01L 27/14 D 31/00 AF term (reference) 2G088 EE01 FF02 GG19 GG20 JJ05 JJ10 JJ12 JJ29 JJ37 4M118 AA10 AB01 BA05 BA12 BA14 CA08 CA32 CB06 CB11 CB14 EA01 FA06 FB13 GA10 GB01 GB09 GD15 HA14 HA17 HA24 HA30 HA31 HA36 5C024 AX11 CY47 CY48 EX21 EX22 EX25 5F088 AA01 BA15 BA16 BA18 JA10 HA15 BB03 HA15 BB03 HA15

Claims (4)

[Claims] 1. A solid-state imaging device having a light-receiving portion, an X-ray blocking member which is disposed in front of the solid-state imaging device in the X-ray incident direction and has an opening at a position corresponding to the light-receiving portion. An X-ray image pickup device, comprising: a scintillator grown on the surface of the light receiving unit in a state in which the X-ray shield member is arranged in front of the solid-state image pickup element in the X-ray incident direction. . 2. A wiring further provided outside the light receiving portion when viewed from the X-ray incidence direction, for taking out a signal output of the solid-state imaging device, and a protective resin covering the wiring. The X-ray image pickup device according to claim 1. 3. The X-ray image pickup device according to claim 1, further comprising an electrically insulating organic film formed to cover the scintillator. 4. An X-ray shielding member having an opening provided at a position corresponding to the light receiving section, in front of an X-ray incident direction of a solid-state imaging device having a light receiving section in which a plurality of photoelectric conversion elements are arranged. A scintillator is grown on the surface of the light receiving section in a state where the X-ray shielding member is arranged in front of the solid-state image pickup element in the X-ray incident direction.