JP7337663B2 - Method for manufacturing radiation detection device - Google Patents

Description

The present invention relates to a method for manufacturing a radiation detection device.

2. Description of the Related Art Improvements have been made in the manufacturing technology of matrix panels for display devices such as liquid crystal displays using thin film transistors (TFTs). This manufacturing technique is applied to a matrix panel as a large-area ellisensor having switching elements such as TFTs and photoelectric conversion elements made of semiconductors. This matrix panel is combined with a scintillator that converts radiation such as X-rays into light such as visible light and is used in the field of radiation detection devices such as medical X-ray imaging devices. This matrix panel was generally formed on a glass substrate, but in recent years, a flexible matrix panel using a resin substrate or the like is expected to reduce the weight of the device and to withstand shock and deformation with high reliability. are being developed and are being used in radiation detectors.

As a method of forming a flexible matrix panel, it is common to place a thin film of a resin material or the like on a rigid substrate such as a glass substrate, and form an area sensor on the thin film. Such a flexible matrix panel is used by separating it from unnecessary glass substrates in order to reduce the weight of the device, as disclosed in Patent Document 1, for example. In Patent Document 1, a matrix is formed by forming a flexible insulating film made of a resin material such as polyimide (hereinafter referred to as PI) on a substrate such as glass, and forming a plurality of photoelectric conversion elements made of TFTs and semiconductors on the flexible insulating film. Prepare the panel. Patent Document 1 discloses a process of arranging a scintillator and a protective member for protecting the scintillator on a matrix panel and peeling off a substrate such as glass in this state.

JP 2009-133837 A

However, the peeling of the substrate in Patent Document 1 is performed by irradiating laser light, but the device itself for generating laser light is large and expensive in order to efficiently irradiate the matrix panel. can be. Therefore, when manufacturing a flexible matrix panel having an area sensor and a scintillator on a flexible insulating substrate, there are problems in terms of manufacturing cost and manufacturing stability.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for manufacturing a radiation detection apparatus that enables stable manufacturing of a flexible matrix panel having area sensors and scintillators on a flexible insulating substrate while reducing the cost thereof. is to provide

A method of manufacturing a radiation detection device according to the present invention for solving the above-mentioned problems is to provide a pixel array having a plurality of pixels each having a photoelectric conversion element provided on a flexible insulating layer provided on a substrate. a forming step of forming a scintillator that converts radiation into light; and a peeling step of peeling the flexible insulating layer from the substrate using a roller to which a fixing member provided at the end of the flexible insulating layer is fixed. wherein the fixing member includes a fixing portion, which is a portion positioned at an end and fixed to the roller, and a bending portion having flexibility, In the peeling step, the flexible insulating layer is peeled off from the substrate using the roller while fixing the fixed portion to the roller and bending the flexible portion.

According to the present invention, it is possible to provide a method for manufacturing a radiation detection device that can stably manufacture a flexible matrix panel having an area sensor and a scintillator on a flexible insulating substrate while reducing the cost. .

Schematic diagram of a radiation detection system using a radiation detector Schematic plan view and cross-sectional view of a radiation detection panel incorporated in a radiation detection device Schematic perspective view and cross-sectional view for explaining the peeling unit Schematic perspective view and cross-sectional view for explaining a comparative example Flow chart for explaining a method for manufacturing a radiation detection device Schematic side view and plan view for explaining an example of a method for manufacturing a radiation detection device Schematic plan view for explaining an example of a method for manufacturing a radiation detection device Schematic side view and plan view for explaining an example of a method for manufacturing a radiation detection device Schematic side view and plan view for explaining an example of a method for manufacturing a radiation detection device Schematic side view and plan view for explaining an example of a method for manufacturing a radiation detection device Schematic side view and plan view for explaining an example of a method for manufacturing a radiation detection device Schematic perspective view for explaining an example of a method for manufacturing a radiation detection device Schematic diagram for explaining the effect of the manufacturing method of the radiation detection device

The invention will now be described through its exemplary embodiments with reference to the accompanying drawings. In addition, the following embodiments do not limit the invention according to the scope of claims. Although multiple features are described in the embodiments, not all of these multiple features are essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant description is omitted. Moreover, the term radiation can include, for example, α-rays, β-rays, γ-rays, particle rays, and cosmic rays in addition to X-rays.

FIG. 1 is a schematic diagram of a radiation detection system using the radiation detection apparatus of the present invention. In FIG. 1, 11 is a subject, 12 is a radiation detector, 13 is a radiation generator, and 14 is a processor. The radiation detection device 12 and the radiation generation device 13 are connected to the processing section 14 . Radiation is emitted from the radiation generator 13 according to control by the processing unit 14, and the radiation detection device 12 detects the radiation transmitted through the subject. The radiation detection apparatus 12 transmits information on the detected radiation as a signal to the processing unit 14, and the processing unit 14 performs desired arithmetic processing to generate a radiographic image for diagnosis.

Next, the radiation detection panel 100 incorporated in the radiation detection apparatus will be described with reference to FIGS. 2(a) to 2(c). FIG. 2(a) is a plan view of the radiation incident surface of the radiation detection panel 100, and FIGS. 2(b) and 2(c) are cross sections showing respective examples between AA' in FIG. 2(a). It is a diagram.

The matrix panel 110 has a pixel array 112 and an external circuit connection section 132 arranged on a flexible insulating layer 111 . A flexible insulating layer 111 is provided on a substrate 114, and the substrate 114 can be made of a material that has high rigidity and can withstand the temperature at which photoelectric conversion elements and TFTs are formed. As the substrate 114, an insulating substrate made of glass or ceramics is particularly preferable. The flexible insulating layer 111 can also be made of a material that can withstand the formation temperature of the photoelectric conversion element or TFT and has high workability. As the flexible insulating layer 111, an organic insulating layer such as polyimide or polyamide is used. The method of forming the matrix panel 110 includes a method of first applying and curing a liquid flexible insulating layer 111 to the substrate 114, and a method of press-bonding the sheet-like flexible insulating layer 111 to the substrate 114. A flexible insulating layer 111 is formed on a substrate 114 . At this time, an adhesive layer may be used between the substrate 114 and the flexible insulating layer 111 . Next, on the flexible insulating layer 111, a pixel array 112 in which a plurality of pixels each having a photoelectric conversion element and a TFT are arranged, and an external circuit connection portion 132 are formed. The pixel array 112 is connected to a plurality of pixels (not shown), drive lines that are wirings for controlling the TFTs, bias lines that are wirings for supplying a bias to the photoelectric conversion elements, and one of the source and drain electrodes of the TFTs. It consists of signal lines, etc. The sensor protection layer 113 is formed for the purpose of protecting the pixel array 112 . As the material of the sensor protective layer 113, it is desirable to use a material that can withstand the heat during the formation of the scintillator 120 and a material that improves the adhesion of the scintillator 120. FIG. Various resins such as urethane resin, acrylic resin, phenol resin, epoxy resin, unsaturated polyester resin, polyimide resin, silicone resin, and diallyl phthalate resin are used as the sensor protective layer 113 .

The scintillator 120 refers to a member having a function of converting radiation such as X-rays into visible light, and the scintillator 120 includes the scintillator layer 121, the adhesive layer 122, the scintillator protective layer 123, and the like. do. As the scintillator layer 121, GOS obtained by mixing scintillator particles and a binder, or cesium iodide (CsI) obtained by activating thallium (Tl) or sodium (Na) is suitable. In the scintillator layer 121 using GOS, a method of coating GOS on the pixel array 112 or a method of laminating a sheet is adopted. In addition, in the scintillator layer 121 using CsI, it is common to use a vapor deposition method under vacuum, and a plurality of columnar crystals having a diameter of about 1 to several tens of microns are formed on the pixel array 112 to a desired thickness. grown and formed. A feature of CsI is that there are gaps between the pillars of the crystal, and it is possible to obtain a high MTF (Modulation Transfer Function). Also, for the scintillator 120 using either GOS or CsI material, there is a method of forming the scintillator 120 on the pixel array 112 by coating or vapor deposition as shown in FIG. 2(b). Alternatively, as shown in FIG. 2C, a separately prepared scintillator base 124 on which phosphors 121 are formed is bonded onto the pixel array 112 with an adhesive layer 125 interposed therebetween. In either method, a scintillator protective layer 123 covering the scintillator layer 121 can be formed to protect the scintillator layer 121 . As the scintillator protective layer 123, metals such as aluminum, copper, and stainless steel, resins such as polyparaxylylene, epoxy resin, acrylic resin, and polyester resin, composite materials made of resin and ceramics such as alumina and titanium oxide, and the like are used. It is possible to use

The radiation detection panel 100 is called a laminate composed of the matrix panel 110 and the scintillator 120 . A wiring member 131 such as a flexible wiring board can be connected to the pixel array 112 of the radiation detection panel 100 via an external circuit connection section 132 . Also, the radiation detection panel 100 may be provided with a support substrate 133 . The necessary functions of the support substrate 133 differ depending on the required properties of the radiation detection panel 110, such as improving the rigidity and moisture resistance of the flexible insulating layer 111, improving the light shielding and external noise resistance of the radiation detection panel 110, or It is desirable to have a vibration and external stress buffering function.

Next, as shown in FIGS. 3A and 3B, the peeling unit 140 includes a roller 141 and a clamp 142 that fixes the peeling target, and peels the peeling target along the roller 141. It has a mechanism that The fixing method may be a method in which the clamp 142 is sandwiched alone, or a fixing method in which the roller 141 and the clamp 142 are sandwiched. Alternatively, the object to be peeled may be adhered and fixed to the roller 141 with an adhesive sheet 147, tape, or the like. It is desirable that the roller width of the roller 141 of the peeling unit 140 is at least greater than the width of the scintillator 120 in order to prevent the scintillator 120 from breaking. Further, by moving the roller 141 on a trajectory that does not step on the wiring member 131, it is possible to prevent the wiring member 131 from breaking and an electrical short circuit. In addition, the external size and surface hardness can be selected according to the size, height, and material of the workpiece (object to be separated). Since it is preferable that the peeling unit 140 installs a fixing member (clamp film) at the end of the peeling target rather than fixing the peeling target as it is and peels the entire fixing member, the clamp film 143 as the fixing member is further removed. include.

Here, the problems found by the inventors of the peeling method using the peeling unit 140 will be described with reference to comparative examples shown in FIGS. When the scintillator 120 is arranged on the pixel array 112 of the flexible insulating layer 111 , the rigidity of the scintillator 120 is extremely large compared to the flexible insulating layer 111 . When the substrate 114 of the radiation detection panel 100, which is such a laminated body, is peeled off from the substrate 114 by the roller 141, the flexible insulating layer 111 is separated at the stepped boundary of the scintillator 120 as shown in FIGS. may break. In order to perform peeling in such a state, it is conceivable to increase the rotational force of the roller 141 . However, since increasing the rotational force of roller 141 also increases the force for stretching flexible insulating layer 111, there is a risk that flexible insulating layer 111 will be stretched and matrix panel 110 will be damaged. Further, when the rotational force of the roller 141 is increased, if the adhesion of the substrate 114 loses to the rotational force, the adhesion of the substrate 114 is released and the substrate 114 is carried by the rollers, and the substrate 114 may be damaged. As a countermeasure, it is conceivable to increase the adsorption force, but an increase in the size of the adsorption mechanism is unavoidable. It is also conceivable to reduce the stretching force by reducing the diameter of the roller 141 for peeling.

Therefore, the inventors of the present application have found the following solutions as a result of earnest studies. The clamp film 143 includes a fixing portion 144 that is fixed to the roller 141 and a bending portion 145 that has flexibility. The fixing portions 144 are preferably located at the ends of the peeling side, as in the first example shown in FIGS. 6A and 6B, and at both ends of the peeling side. The position is arranged at least outside the scintillator 120, and as shown in FIG. Furthermore, as shown in FIG. 7(b), the scintillator 120 may extend beyond the end boundary 146 of the scintillator 120. FIG. This increases the stiffness of the edge boundary 146 of the scintillator 120 and allows it to be peeled off more easily. The clamp film 143 may be made of any material as long as it can be formed into a sheet, and preferably has high tensile strength and little elongation. As for the bonding method of the clamp film 143, the back surface of the film and the flexible insulating layer 111 may be bonded with an adhesive sheet 147 or resin. Alternatively, as in a second example shown in FIGS. 8A and 8B, the ends of the clamp film 143 and the ends of the flexible insulating layer 111 may be fixed from above with an adhesive sheet 147. . Also, the adhesive sheet 147 may be used as a clamp film. Also, as in the third example shown in FIGS. 9A and 9B, the clamp film 143 may be divided into two and placed on the flexible insulating layer 111 . In this case, the regions of the flexible insulating layer 111 located between the clamp films 143 function as flexures. It is also possible to directly use part of the flexible insulating layer 111 of the radiation detection panel 110 as the clamp film 143, as in the fourth example shown in FIGS. 10(a) and 10(b).

In addition, as in the fifth example shown in FIGS. 11A and 11B, a clamp film 143 is placed on the flexible insulating layer 111 in parallel with the peeling line, and only two ends of the clamp film 143 are attached. A similar effect can be obtained by partially fixing the with a clamp 142 . As for the shape of this clamp 142, as shown in FIG. 12(a), a divided clamp 142 may be used, or as shown in FIG. It's okay. Moreover, as shown in FIG. 12(c), spacers 148 may be arranged at both ends of the straight clamp 142. FIG.

By peeling the flexible insulating layer 111 fixed to the roller 141 by the above method from the substrate 114, as shown in FIG. , peeling starts from the periphery. Thereafter, as shown in FIG. 11(b), the peeling line gradually becomes perpendicular to the moving direction of the roller 141 and reaches its end. Thus, the peeling of the radiation detection panel 110 is completed. With this peeling method, the radiation detection panel 110 can be peeled obliquely without changing the moving direction of the roller 141, and the work can be peeled off with a light peeling force without applying a load.

Next, a method of manufacturing a radiation detection device having the radiation detection panel 140 using the peeling method described above will be described with reference to FIGS. 5(a) and 5(b).

In the first example shown in FIG. 5(a), the matrix panel 110 can be prepared by known techniques in step S501. Next, in step S502, a scintillator 120 can be formed on the pixel array 112 of the prepared matrix panel 110 by known techniques. Next, in step S503, the wiring member 131 can be electrically connected to the external circuit connection portion 132 of the matrix panel 110 by a known method. As shown in the second example of FIG. 5B, the order of forming the scintillator in step S502 and connecting the wiring member 131 in step S503 may be reversed. Here, when the scintillator layer 121 is formed on the matrix panel 110 by direct vapor deposition, the first example can be preferably used. On the other hand, when the scintillator 120 is formed on the matrix panel via an adhesive layer, the second example can be preferably used.

Next, in step S504, a peeling process is performed using at least one of the first to fifth examples described above. The peeling process using this method can reduce the possibility that the flexible insulating layer 111 will be stretched and the matrix panel 110 will be damaged. In addition, the risk of damage to the substrate 114 can be reduced without increasing the size of the adsorption mechanism. Also, the risk of damage to the photoelectric conversion elements of the matrix panel 110 and the scintillator 120 can be reduced.

Then, in step S505, the support substrate 133 can be placed via an adhesive (not shown) on the surface of the peeled flexible insulating layer 111 opposite to the surface on which the scintillator 120 is placed. This improves the handling of the matrix panel 110 during the manufacturing process. Next, in step S506, a circuit board such as a printed circuit board (PCB) is electrically connected to the wiring member 131, and the radiation detection panel 100 can be prepared.

111 Flexible insulating layer 112 Pixel array 114 Substrate 120 Scintillator 141 Roller 143 Fixed member 144 Fixed part 145 Flexible part

Claims (10)

a formation step of forming a scintillator for converting radiation into light on a pixel array having a plurality of pixels each having a photoelectric conversion element provided on a flexible insulating layer provided on a substrate;
a peeling step of peeling the flexible insulating layer from the substrate using a roller to which a fixing member provided at an end of the flexible insulating layer is fixed;
A method for manufacturing a radiation detection device that performs
The fixing member includes a fixing portion, which is a portion positioned at an end and fixed to the roller, and a bending portion having flexibility,
In the peeling step, the flexible insulating layer is peeled off from the substrate using the roller while the fixed portion is fixed to the roller and the flexible portion is bent. . 2. The method of manufacturing a radiation detection apparatus according to claim 1, wherein the fixing portions are provided at both ends of the fixing member. 3. The method of manufacturing a radiation detection apparatus according to claim 1, wherein the fixing portion is provided outside the scintillator. 4. The method of manufacturing a radiation detecting device according to claim 1, wherein the fixing portion is provided so as to protrude to the outside of the flexible insulating layer. 5. The method of manufacturing a radiation detecting apparatus according to claim 1, wherein the fixed portion is provided up to a position beyond an end boundary of the scintillator. 6. The method of manufacturing a radiation detector according to claim 1, wherein the fixing member is a part of the flexible insulating layer. 7. The method according to any one of claims 1 to 6, wherein in the peeling step, only an end portion of the fixing member is fixed to the roller and the flexible insulating layer is peeled from the substrate using the roller. A method for manufacturing the radiation detection device according to claim 1. 8. The method according to any one of claims 1 to 7, further comprising a step of placing a support substrate on the surface of the flexible insulating layer separated from the substrate, opposite to the surface on which the scintillator is placed. 2. A method for manufacturing the radiation detection device according to item 1. The flexible insulating layer has an external circuit connection portion electrically connected to the pixel array,
9. The method of manufacturing a radiation detecting apparatus according to claim 1, further comprising a connecting step of electrically connecting a wiring member to said external circuit connecting portion. 10. The method of manufacturing a radiation detecting device according to claim 9, wherein the connecting step is performed before the forming step.

Images