JP2009240861A - Liquid coating method, liquid coating device, and method of manufacturing radiation detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid coating method, a liquid coating device, and a method of manufacturing a radiation detector that shorten the time required when applying liquid to the surface of a substrate. <P>SOLUTION: As indicated in Fig.5(a), the droplets L discharged from a nozzle 22 are discharged in the state of such a columnar shape that a length L10 (called a liquid column length, hereafter) in a discharge direction is long compared to the dimension of the cross section of the droplet, and are landed in the columnar shape as they are before being condensed to a spherical shape on the substrate 16. When landed on the substrate 16, the lower end part of the droplet L is pulled in the scanning direction of the substrate 16. Thus, an angle θ formed by the longitudinal direction of the droplet L and the substrate 16 becomes less than 90°, and the droplet L is coated so as to be spread in the longitudinal direction on the substrate 16 as indicated in Fig.5(b). Then, the droplet L is wetly spread as indicated by a code L' in Fig.5(b). That is, the droplet L is wetly spread in a short time and in a wide range compared to the case of being landed after being contracted to the spherical shape. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid coating method, a liquid coating apparatus, and a radiation detector manufacturing method, and more particularly to a liquid coating method, a liquid coating apparatus, and a radiation detector manufacturing method in which a liquid is applied to the surface of a substrate using an inkjet head.

Patent Document 1 discloses a liquid material that applies a liquid material onto a substrate by operating a liquid droplet ejection unit provided in the ejection head to form a liquid material in the ejection head into droplets and ejecting the liquid material from a nozzle. In this application method, the liquid material is applied in a non-uniform discharge state.
JP 2005-40653 A

  When the liquid is applied to the surface of the substrate using the ink jet head, there is a problem that it takes longer to apply the liquid and to dry the liquid on the surface of the substrate as the area of the liquid application region increases.

  Patent Document 1 is not intended to shorten the time required for applying the liquid. Patent Document 1 does not describe the composition of the liquid.

  The present invention has been made in view of such circumstances, and provides a liquid coating method, a liquid coating apparatus, and a radiation detector manufacturing method capable of reducing the time required for coating a liquid on a substrate surface. With the goal.

  In the liquid application method according to the first aspect of the present invention, when a droplet is ejected by a recording head having a plurality of nozzles on a substrate placed on a support plate, the recording head and the substrate While maintaining a predetermined clearance therebetween, the recording head and the support plate are scanned relatively by using scanning means, and columnar droplets extending in the ejection direction are ejected from the nozzles, and the droplets are spherical. The lower end of the droplet is landed on the substrate before shrinking.

  In the liquid coating method according to the second aspect of the present invention, in the first aspect, the recording head is configured such that the lower end portion of the droplet and the upper end portion of the droplet land on different positions on the substrate. And the support plate are relatively scanned.

  The liquid application method according to a third aspect of the present invention is the liquid application method according to the first or second aspect, wherein the liquid droplets have a dilatancy property by adjusting a shear rate when the liquid droplets are discharged from the nozzle. Thus, the droplets are landed on the substrate before shrinking into a spherical shape.

The liquid application method according to a fourth aspect of the present invention is the liquid application method according to the third aspect, wherein the droplet has a viscosity at a shear rate of 10 ⁶ [1 / s] of 25 cP or more.

  A liquid coating apparatus according to a fifth aspect of the present invention is a recording head having a support plate on which a substrate is placed, and a plurality of nozzles that eject droplets to the substrate placed on the support plate. Scanning means for relatively scanning the recording head and the substrate while maintaining a predetermined clearance between the recording head and the substrate, and the recording head and the substrate are relatively moved by the scanning means. And a control unit that discharges a columnar droplet extending in the discharge direction from the nozzle while causing the droplet to land on the substrate before the droplet contracts into a spherical shape.

  In the liquid application apparatus according to a sixth aspect of the present invention, in the fifth aspect, the scanning unit causes the lower end portion of the droplet and the upper end portion of the droplet to land at different positions on the substrate. As described above, the recording head and the support plate are relatively scanned.

  The liquid application apparatus according to a seventh aspect of the present invention is the liquid application apparatus according to the fifth or sixth aspect, wherein the control means adjusts a shear rate when the liquid droplet is discharged from the nozzle. By providing the liquid crystal with a dilatancy, the liquid droplets are landed on the substrate before shrinking into a spherical shape.

The liquid application apparatus according to an eighth aspect of the present invention is the liquid application apparatus according to the seventh aspect, wherein the droplet has a viscosity at a shear rate of 10 ⁶ [1 / s] of 25 cP or more.

  A liquid application apparatus according to a ninth aspect of the present invention is the liquid application apparatus according to any of the fifth to eighth aspects, wherein the droplet has a viscosity of 25 cP or more.

  A liquid application apparatus according to a tenth aspect of the present invention is the liquid application apparatus according to any one of the fifth to ninth aspects, wherein the surface tension or dynamic surface tension of the droplet is 10 mN / m or less.

  The radiation detector manufacturing method according to the present invention includes a first electrode through which radiation carrying image information is transmitted, a photoconductive layer that is irradiated with the radiation transmitted through the first electrode to generate charges, and the photoconductive A second electrode that is provided on the opposite side of the layer from the side on which the first electrode is provided and collects the charge generated by the photoconductive layer; and between the photoconductive layer and the first electrode A method of manufacturing a radiation detector comprising an organic polymer layer provided on the organic polymer layer, wherein the organic polymer layer is formed using the liquid application method according to the first to fourth aspects. is there.

  According to the present invention, the liquid droplets discharged from the nozzles are landed so as to extend long on the substrate before becoming spherical, so that the liquid droplets are wetted and spread compared to the case where the liquid droplets are landed after becoming spherical. The time until is shortened, and the coating time is shortened. As a result, the surface area of the gas-liquid interface can be increased more quickly than when the droplet is landed after it has become spherical, so the drying time of the droplet can be shortened. The production speed of the product made by applying is improved.

  Hereinafter, preferred embodiments of a liquid coating method, a liquid coating apparatus, and a radiation detector manufacturing method according to the present invention will be described with reference to the accompanying drawings.

[Configuration of liquid coating device]
FIG. 1 is a perspective view showing a liquid coating apparatus according to the first embodiment of the present invention.

  As shown in FIG. 1, a liquid coating apparatus (inkjet recording apparatus) 10 according to the present embodiment includes an inkjet head (hereinafter referred to as a recording head) 12 and a support plate 14.

  The recording head 12 is a line type recording head in which nozzles 22 are arranged over the entire width of the substrate 110 in the y direction.

  On the support plate 14, a substrate 16 that is a target to which liquid is applied by the recording head 12 is placed. The support plate 14 is supported so that the clearance with the recording head 12 is constant, and can be scanned in the main scanning direction (x direction in FIG. 1).

  By discharging droplets from the recording head 12 while scanning the support plate 14 in the x direction, it is possible to apply the liquid to the entire drawing region of the substrate 16.

  FIG. 2 is a plan view showing a surface on which the nozzles of the recording head 12 are formed.

  As shown in FIG. 2, the recording head 12 has the ejection elements 20 including the nozzles 22 and the pressure chambers 24 at substantially equal intervals along the sub-scanning direction (y direction) substantially orthogonal to the main scanning direction (x direction). It has a side-by-side structure.

  For example, the nozzle diameter of the recording head 12 is 35 μmφ, and the nozzle pitch is 254 μm (100 npi). The recording head 12 can continuously eject droplets at a droplet ejection period of 1 kHz and a head scanning speed of 0.1 m / s.

  In addition, when the recording head 12 is configured with high density so that the dots formed by the droplets ejected from the adjacent nozzles overlap each other, the droplets are not ejected simultaneously from the adjacent nozzles and are ejected simultaneously every other nozzle. A mode in which thinning control is performed so as to perform droplets and an area that can be drawn by one scan is divided into two scans is preferable.

  FIG. 3 is a cross-sectional view showing the ejection element 20.

  The pressure chamber 24 provided corresponding to the nozzle 22 has a substantially square planar shape. An outlet to the nozzle 22 is provided at one of the diagonal corners of the pressure chamber 24, and a liquid supply port 26 to the pressure chamber 24 is provided at the other. The planar shape of the pressure chamber 24 may have various forms other than the above-described square, such as a quadrangle (diamond, rectangle), a pentagon, a hexagon, other polygons, a circle, and an ellipse.

  As shown in FIG. 3, the pressure chamber 24 of the ejection element 20 communicates with the common flow path 28 via the supply port 26. The common flow path 28 communicates with a tank (not shown) as a liquid supply source, and the liquid supplied from the tank is distributed and supplied to each pressure chamber 24 via the common flow path 28.

  A piezoelectric element 34 having individual electrodes 32 is joined to a pressure plate (vibrating plate that also serves as a common electrode) 30 constituting a part of the pressure chamber 24 (the top surface in FIG. 3). In addition, as a material of the piezoelectric element 34, for example, a piezoelectric body such as lead zirconate titanate (PZT) or barium titanate can be used.

  When a drive signal is applied between the individual electrode 32 and the common electrode, the piezoelectric element 34 is deformed and the volume of the pressure chamber 24 changes. As a result, the pressure in the pressure chamber 24 changes, whereby droplets are ejected from the nozzle 22. Then, when the displacement of the piezoelectric element 34 is restored after the liquid is discharged, the pressure chamber 24 is refilled with the new liquid from the common flow path 28 through the supply port 26.

  In the present embodiment, a method of pressurizing ink by deformation of the piezoelectric element 34 is employed, but an actuator of a method other than the above (for example, a thermal method) may be applied.

  Although illustration is omitted, the liquid coating apparatus 10 includes a supply system for supplying a liquid to the recording head 12 and a maintenance unit that performs maintenance of the recording head 12.

  FIG. 4 is a block diagram showing a control system of the liquid coating apparatus 10.

  The liquid coating apparatus 10 includes a communication interface 40, a system controller 42, a memory 46, a motor driver 48, a heater driver 52, a droplet ejection control unit 56, a buffer memory 58, and a head driver 60.

  The communication interface 40 is an interface unit that receives droplet ejection data sent from the host computer 80. As the communication interface 40, a serial interface such as USB (Universal Serial Bus), IEEE 1394, Ethernet (registered trademark), a wireless network, or a parallel interface such as Centronics can be applied. Note that a buffer memory for speeding up communication may be mounted in this portion.

  The system controller 42 includes a central processing unit (CPU) and its peripheral circuits, and is a control unit that controls each part of the liquid coating apparatus 10. The system controller 42 performs communication control with the host computer 80, read / write control of the memory 46, and the like, and generates control signals for controlling the motor 50 and the heater 54 of the transport drive system.

  The program storage unit 44 stores a control program for the liquid application apparatus 10. The system controller 42 appropriately reads out various control programs stored in the program storage unit 44 and executes the control programs.

  The memory 46 is storage means used as a temporary storage area for data and a work area when the system controller 42 performs various calculations. As the memory 46, a magnetic medium such as a hard disk can be used in addition to a memory made of a semiconductor element.

  The motor 50 is a motor for relatively scanning the recording head 12 and the support plate 14 of FIG. The motor driver 48 drives the motor 50 in accordance with a control signal from the system controller 42.

  The heater driver 52 drives the heater 54 in accordance with a control signal from the system controller 42. The heater 54 includes a temperature adjusting heater provided in each part of the liquid coating apparatus 10.

  The droplet ejection data sent from the host computer 80 is taken into the liquid coating apparatus 10 via the communication interface 40 and temporarily stored in the memory 46.

  The droplet ejection control unit 56 has a signal processing function for performing various processing and correction processing for generating a discharge control signal from the droplet ejection data in the memory 46 according to the control of the system controller 42. A control unit that supplies a discharge control signal (discharge data) to the head driver 60. The droplet ejection control unit 56 performs necessary signal processing, and controls the liquid ejection amount and ejection timing of the recording head 12 via the head driver 60 based on the droplet ejection data.

  The head driver 60 drives the piezoelectric element 34 of the recording head 12 based on the ejection data given from the droplet ejection control unit 56. The head driver 60 may include a feedback control system for keeping the head driving condition constant.

  The droplet ejection control unit 56 includes a buffer memory 58, and droplet ejection data, parameters, and other data are temporarily stored in the buffer memory 58 when droplet ejection data is processed by the droplet ejection control unit 56.

  The buffer memory 58 can also be used as the memory 46. Further, a mode in which the droplet ejection control unit 56 and the system controller 42 are integrated and configured by one processor is also possible.

[Droplet ejection control]
FIG. 5 is a diagram schematically showing the discharge shape of the droplet.

  As shown in FIG. 5A, the droplet L ejected from the nozzle 22 has a column shape in which the length in the ejection direction (hereinafter referred to as the “liquid column length”) L10 is longer than the size of the cross section of the droplet. Before being shrunk into a spherical shape on the substrate 16 and landing in a columnar shape. When the lower end of the droplet L reaches the substrate 16, it is pulled in the scanning direction of the substrate 16. As a result, the angle θ formed by the longitudinal direction of the droplet L and the substrate 16 becomes less than 90 °, and the droplet L is applied on the substrate 16 so as to extend in the longitudinal direction, as shown in FIG. The Then, the droplet L spreads out as shown by the symbol L ′ in FIG. That is, the droplet L wets and spreads in a shorter time compared to the case where the droplet L is landed after contracting into a spherical shape. When the lower end portion of the droplet L comes into contact with the substrate 16, the upper end portion (tail portion) of the droplet L may be connected to the nozzle 22 or may be separated.

  As a method for causing the droplet L to land on the substrate 16 in a columnar shape, the viscosity of the droplet L is increased, the droplet L is given dilatancy, the surface tension of the droplet L is decreased, the droplet There is a method of reducing the dynamic surface tension of L or significantly increasing the discharge speed when the droplet L is discharged from the nozzle 22 (giving the actuator for discharging very large energy (voltage)). . Here, the dynamic surface tension is a surface tension in a flow / stirring state where the interface of the droplet L is unstable.

  The distance from the nozzle 22 to the substrate 16 (slow distance of the droplet L) z10 is preferably as short as possible. As a result of observing the discharge of the droplet L, when the volume of the droplet L is 30 pl (liquid column length L10 is about 1.5 mm), the slow distance z10 is preferably about 1.5 mm or less.

  In addition, it is preferable to make the contact angle between the substrate 16 and the droplet L as small as possible (in an example, 5 ° or less).

  Specifically, as shown in Table 1, when the surface tension of the droplet L was 30 mN / m, the column shape was maintained until the droplet L landed on the substrate 16 if the viscosity was 25 cP or more. It becomes difficult to curl up.

Further, as shown in Table 2, if the shear rate of the droplet L at the nozzle 22 is increased so that the viscosity of the cut portion (tail portion) where the droplet L is separated from the nozzle 22 is 25 cP or more, the droplet L is transferred to the substrate. The pillar shape is maintained until it hits 16 (it becomes difficult to curl). The shear rate of the nozzle part at this time is about 10 ⁶ [1 / s]. In Table 2, the viscosity other than the cut portion of the droplet L was calculated as 3 cP.

  As shown in Table 3, when the viscosity of the droplet L is 3 cP, if the surface tension is 10 mN / m or less, the columnar shape is maintained until the droplet L reaches the substrate 16 (it is difficult to be rounded). ).

  In addition, the standard of the difficulty of rounding in the above Tables 1 to 3 is based on the nozzle 22 and the liquid droplet in the simulation using the three-dimensional general-purpose thermal fluid analysis software Flow-3D, using the inkjet head SE-128 manufactured by FUJIFILM Dimatix as a model. When the liquid column length L10 when L is divided is 650 μm or more, it is difficult to be rounded.

  The results in Table 4 are generally consistent with the simulation results of whether or not the liquid droplets are rounded at a location about 1.5 mm away from the nozzle 22 when the simulation time is advanced.

  6 and 7 are diagrams showing simulation results by the three-dimensional general-purpose thermal fluid analysis software Flow-3D.

  FIGS. 6A and 7A show the shape of the droplet L and the velocity distribution in the z direction of the droplet L at the moment when the tail portion L_nzl of the droplet L leaves the nozzle 22. 6 (b) and FIG. 7 (b) show the shape of the droplet L and the velocity distribution in the z direction of the droplet L at the instant when a certain time has elapsed from the moment of FIG. 6 (a) and FIG. 7 (a), respectively. Is shown. The unit of length in FIGS. 6 and 7 is cm.

  In the simulation of FIG. 6, the diameter of the nozzle 22 (diameter of the hole in the tapered portion in the drawing) is 35 μmφ, the viscosity of the droplet L is 25 cP, the viscosity at the tail portion L_nzl of the nozzle 22 is 3 cP, and the discharge speed is 8.3 m / s. In the simulation of FIG. 7, the diameter of the nozzle 22 (diameter of the hole in the tapered portion in the figure) is 35 μmφ, the viscosity of the droplet L is 25 cP, the viscosity at the tail portion L_nzl of the nozzle 22 is 25 cP, and the discharge speed is 8. It was 3 m / s.

  According to the present embodiment, the droplet L ejected from the nozzle 22 is landed on the substrate 16 before it becomes spherical, so that the droplet L spreads more wet than when landed after becoming spherical. The time until completion is shortened and the application time is shortened. As a result, the surface area of the gas-liquid interface can be increased more quickly than when the droplet is landed after it has become spherical, so the drying time of the droplet can be shortened. The production speed of the product made by applying is improved.

  In the present embodiment, the droplets L are formed in a columnar shape, but, for example, a plurality of droplets are continuously ejected in one scan, or droplets are ejected in a mist form (spray coating). ) The droplets may be coalesced on the substrate.

[Another Embodiment of Liquid Coating Apparatus]
Next, another embodiment of the liquid coating apparatus 10 will be described.

  8 to 16 are perspective views showing another embodiment of the liquid coating apparatus 10.

  The liquid coating apparatus 10 shown in FIG. 8 is configured such that the recording head 12 is scanned in the x direction and the support plate 14 is scanned in the y direction.

  The liquid coating apparatus 10 shown in FIG. 9 is configured such that the recording head 12 is scanned in the y direction and the support plate 14 is scanned in the x direction.

  The liquid coating apparatus 10 shown in FIG. 10 is configured such that the recording head 12 is scanned in the x direction and the y direction.

  The liquid coating apparatus 10 shown in FIG. 11 is configured such that the support plate 14 is scanned in the x direction and the y direction.

  The liquid coating apparatus 10 shown in FIG. 12 is configured such that the recording head 12 is scanned in the x direction and the support plate 14 is scanned in the x direction and the y direction.

  The liquid coating apparatus 10 shown in FIG. 13 is configured so that the recording head 12 is scanned in the y direction and the support plate 14 is scanned in the x direction and the y direction.

  The liquid coating apparatus 10 shown in FIG. 14 is configured such that the recording head 12 is scanned in the x direction and the y direction, and the support plate 14 is scanned in the x direction.

  The liquid coating apparatus 10 shown in FIG. 15 is configured such that the recording head 12 is scanned in the x direction and the y direction, and the support plate 14 is scanned in the y direction.

  The liquid coating apparatus 10 illustrated in FIG. 16 is configured such that the recording head 12 is scanned in the x direction and the y direction, and the support plate 14 is scanned in the x direction and the y direction.

  In any of the examples shown in FIGS. 8 to 16, liquid is applied to the entire drawing region of the substrate 16 by ejecting droplets from the recording head 12 while driving at least one of the recording head 12 and the substrate 16. It is possible to do.

[Embodiment of radiation detector]
Next, an embodiment of a radiation detector created using the liquid coating apparatus 10 according to the present embodiment will be described.

  The radiation detector according to the present embodiment is used in an X-ray imaging apparatus or the like, and includes an electrostatic recording unit including a photoconductive layer that exhibits conductivity when irradiated with radiation. The image information is recorded upon receiving the irradiation of the radiation carrying the image, and the image signal representing the recorded image information is output.

  As the radiation detector, a so-called optical reading type radiation detection substrate 500 that reads using a semiconductor material that generates charges by light irradiation, and charges generated by radiation irradiation are accumulated, and the accumulated charges are stored in a thin film transistor. There is a radiation detector 400 or the like of a method of reading by turning on and off an electrical switch such as a TFT (thin film transistor) one pixel at a time (hereinafter referred to as TFT method).

(Configuration of TFT radiation detector 400)
First, the configuration of the TFT radiation detector 400 will be described. FIG. 17A is a schematic diagram showing an overall configuration of a TFT radiation detector 400. FIG. 18 shows a configuration of a main part of a TFT radiation detector 400, and shows each part laminated on a glass substrate.

  As shown in FIGS. 17A and 18, the TFT radiation detector 400 according to the present embodiment is a charge that generates charges when X-rays as an example of radiation carrying image information are incident. As the conversion layer, a photoconductive layer 404 exhibiting electromagnetic wave conductivity is provided. As the photoconductive layer 404, an amorphous material having a high dark resistance, good electromagnetic wave conductivity with respect to X-ray irradiation, and capable of forming a large area film at a low temperature by a vacuum deposition method is preferred.

  For example, an amorphous Se (a-Se) film is used as the amorphous material. A material obtained by doping As, Sb, and Ge into amorphous Se is excellent in thermal stability and is a suitable material for the photoconductive layer 404.

  On the photoconductive layer 404, a bias electrode 401 for applying a bias voltage to the photoconductive layer 404 is formed as a first electrode through which radiation carrying image information is transmitted. The bias electrode 401 is made of, for example, gold (Au). The photoconductive layer 404 is irradiated with radiation that has passed through the bias electrode 401.

  Collecting a plurality of charges as a second electrode for collecting the charges generated by the photoconductive layer 404 on the side opposite to the side where the bias electrode 401 is provided with respect to the photoconductive layer 404, that is, below the photoconductive layer 404 An electrode 407a is formed. As shown in FIG. 18, the charge collection electrode 407a is connected to the charge storage capacitor 407c and the switch element 407b, respectively. The charge collection electrode 407a is provided on the glass substrate 408.

  As shown in FIGS. 17A and 18, a hole injection blocking layer 402 having a hole blocking material is provided as an organic polymer layer between the photoconductive layer 404 and the bias electrode 401. ing. Here, the organic polymer layer may also serve as a charge injection blocking layer having charge selectivity. The charge injection blocking layer has charge selectivity, which prevents the charge injection blocking layer from flowing out of the bias electrode 401 with which the charge injection blocking layer is in contact (holes if the bias electrode 401 is positive bias, electrons if it is negative bias). It means that the charge flowing into the bias electrode 401 has a property of passing through.

  That is, as a charge injection blocking layer, a hole injection blocking layer that blocks the injection of holes while being a conductor for electrons, or an electron that blocks the injection of electrons while being a conductor for holes. An injection blocking layer is used. In this embodiment, since the bias electrode 401 is a positive electrode, a hole injection blocking layer 402 is provided as an organic polymer layer.

  As the hole injection blocking layer 402, a film in which a hole blocking material is mixed with an insulating polymer such as polycarbonate, polystyrene, polyimide, polycycloolefin, or the like can be preferably used.

  At least one of the hole blocking materials contained in the hole injection blocking layer 402 is preferably at least one selected from carbon clusters or derivatives thereof. Further, the carbon cluster is preferably at least one selected from fullerene C60, fullerene C70, oxidized fullerene or a derivative thereof.

  Further, as shown in FIG. 18, an electron injection blocking layer 406 is provided between the photoconductive layer 404 and the charge collection electrode 407a.

Further, anti-crystallization layers 403 and 405 are provided between the hole injection blocking layer 402 and the photoconductive layer 404 and between the electron injection blocking layer 406 and the photoconductive layer 404, respectively. The crystallization preventing layer 403, 405 GeSe, can be used and _{GeSe 2, Sb 2 Se 3,} a-As 2 Se 3, Se-As, Se-Ge, a Se-Sb-based compounds.

  Note that an active matrix layer 407 is configured by the charge collection electrode 407a, the switch element 407b, and the charge storage capacitor 407c, and an active matrix substrate 450 is configured by the glass substrate 408 and the active matrix layer 407.

  19 is a cross-sectional view showing the structure of one pixel unit of the radiation detector 400, and FIG. 20 is a plan view thereof. The size of one pixel shown in FIGS. 19 and 20 is about 0.1 mm × 0.1 mm to 0.3 mm × 0.3 mm, and this pixel is arranged in a matrix of about 500 × 500 to 3000 × 3000 pixels in the radiation detector as a whole. Has been.

  As shown in FIG. 19, the active matrix substrate 450 includes a glass substrate 408, a gate electrode 411, a charge storage capacitor electrode (hereinafter referred to as Cs electrode) 418, a gate insulating film 413, a drain electrode 412, a channel layer 415, a contact electrode. 416, a source electrode 410, an insulating protective film 417, an interlayer insulating film 420, and a charge collection electrode 407a.

  The gate electrode 411, the gate insulating film 413, the source electrode 410, the drain electrode 412, the channel layer 415, the contact electrode 416, and the like constitute a switch element 407b made of a thin film transistor (TFT), and a Cs electrode 418. Further, a charge storage capacitor 407c is configured by the gate insulating film 413, the drain electrode 412 and the like.

  The glass substrate 408 is a support substrate. As the glass substrate 408, for example, an alkali-free glass substrate (for example, # 1737 manufactured by Corning) can be used. As shown in FIG. 20, the gate electrode 411 and the source electrode 410 are electrode wirings arranged in a lattice pattern, and a switch element 407b made of a thin film transistor is formed at the intersection.

  The source / drain of the switch element 407b is connected to the source electrode 410 and the drain electrode 412 respectively. The source electrode 410 includes a linear portion as a signal line and an extended portion for constituting the switch element 407b, and the drain electrode 412 is provided so as to connect the switch element 407b and the charge storage capacitor 407c. Yes.

  The source electrode 410 is connected to an extraction electrode 470 that extracts the charges collected by the charge collection electrode 407a to acquire image information. The extraction electrode 470 is provided on the glass substrate 408 and disposed outside the photoconductive layer 404.

  The gate insulating film 413 is made of SiNx, SiOx, or the like. The gate insulating film 413 is provided so as to cover the gate electrode 411 and the Cs electrode 418, and a part located on the gate electrode 411 acts as a gate insulating film in the switch element 407b, and a part located on the Cs electrode 418. Acts as a dielectric layer in the charge storage capacitor 407c. That is, the charge storage capacitor 407c is formed by an overlapping region of the Cs electrode 418 and the drain electrode 412 formed in the same layer as the gate electrode 411. The gate insulating film 413 is not limited to SiNx or SiOx, and an anodic oxide film obtained by anodizing the gate electrode 411 and the Cs electrode 418 can be used in combination.

  A channel layer (i layer) 415 is a channel portion of the switch element 407 b and is a current path connecting the source electrode 410 and the drain electrode 412. A contact electrode (n + layer) 416 makes contact between the source electrode 410 and the drain electrode 412.

  The insulating protective film 417 is formed over almost the entire surface (substantially the entire region) on the source electrode 410 and the drain electrode 412, that is, on the glass substrate 408. Thus, the drain electrode 412 and the source electrode 410 are protected, and electrical insulation and separation are achieved. Further, the insulating protective film 417 has a contact hole 421 at a predetermined position thereof, that is, at a portion located on a portion of the drain electrode 412 facing the Cs electrode 418.

  The charge collection electrode 407a is made of an amorphous transparent conductive oxide film. The charge collection electrode 407a is formed so as to fill the contact hole 421, and is stacked on the source electrode 410 and the drain electrode 412. The charge collection electrode 407a and the photoconductive layer 404 are electrically connected to each other so that charges generated in the photoconductive layer 404 can be collected by the charge collection electrode 407a.

  Next, the charge collection electrode 407a will be described in detail. The charge collection electrode 407a used in this embodiment is composed of an amorphous transparent conductive oxide film. Examples of amorphous transparent conductive oxide film materials include oxides of indium and tin (ITO: Indium-Tin-Oxide), oxides of indium and zinc (IZO: Indium-Zinc-Oxide), indium and germanium. An oxide (IGO: Indium-Germanium-Oxide) or the like having a basic composition can be used.

  As the charge collection electrode 407a, various metal films and conductive oxide films are used, and transparent conductive oxide films such as ITO (Indium-Tin-Oxide) are often used for the following reasons. When the incident X-ray dose is large in the radiation detector 400, unnecessary charges may be trapped in the semiconductor film (or in the vicinity of the interface between the semiconductor film and an adjacent layer).

  Such residual charges are stored in memory for a long time or move while taking time, so that X-ray detection characteristics deteriorate during subsequent image detection, and afterimages (virtual images) appear. Therefore, in Japanese Patent Laid-Open No. 9-9153 (corresponding US Pat. No. 5,563,421), when residual charges are generated in the photoconductive layer 404, the residual charges are reduced by irradiating light from the outside of the photoconductive layer 404. A method of removing by excitation is disclosed. In this case, in order to irradiate light efficiently from the lower side of the photoconductive layer 404 (on the side of the charge collection electrode 407a), the charge collection electrode 407a needs to be transparent to the irradiation light.

  In addition, for the purpose of increasing the area filling factor (fill factor) of the charge collection electrode 407a or for shielding the switch element 407b, it is desirable to form the charge collection electrode 407a so as to cover the switch element 407b. If the collection electrode 407a is opaque, the switch element 407b cannot be observed after the charge collection electrode 407a is formed.

  For example, when the characteristic inspection of the switch element 407b is performed after the charge collection electrode 407a is formed, if the switch element 407b is covered with the opaque charge collection electrode 407a, the cause of the characteristic failure of the switch element 407b is found. Cannot be observed with an optical microscope. Therefore, it is desirable that the charge collection electrode 407a be transparent so that the switch element 407b can be easily observed even after the charge collection electrode 407a is formed.

  The interlayer insulating film 420 is made of a photosensitive acrylic resin, and serves to electrically isolate the switch element 407b. A contact hole 421 passes through the interlayer insulating film 420, and the charge collection electrode 407 a is connected to the drain electrode 412. The contact hole 421 is formed in a reverse taper shape as shown in FIG. A high voltage power supply (not shown) is connected between the bias electrode 401 and the Cs electrode 418.

  Next, a configuration for covering the photoconductive layer 404 will be described. As shown in FIG. 17A, a cover glass 440 as an example of a cover member that covers the bias electrode 401 is provided above the bias electrode 401.

The glass substrate 408 is provided with a protective member 442 to which the cover glass 440 is bonded.
The protective member 442 surrounds the periphery of the photoconductive layer 404, and is formed in a box shape with the upper and lower portions opened as a whole.

  Further, the protective member 442 has a side wall 442a erected on the outer peripheral portion of the glass substrate 408, and a flange portion 442b protruding from the upper part of the side wall 442a to the upper side of the central portion of the glass substrate 408. It is formed in an L shape.

  The cover glass 440 has an upper surface of its outer peripheral portion joined to the lower surface (inner wall) of the flange portion 442b and is supported by the protective member 442.

  The joint between the protective member 442 and the cover glass 440 is disposed outside the photoconductive layer 404. That is, the protective member 442 and the cover glass 440 are bonded to each other in a region where the photoconductive layer 404 on the glass substrate 408 is not present, but not above the photoconductive layer 404.

  Note that an insulating member having an insulating property is used for the protective member 442. As the insulating member, for example, polycarbonate, polyethylene terephthalate (PET), polymethyl methacrylate (acrylic), or polyvinyl chloride is used.

  Further, the protective member 442 has a lower opening closed by a glass substrate 408 and an upper opening closed by a cover glass 440, so that a closed space of a predetermined size is formed in the protective member 442. The photoconductive layer 404 is accommodated in the closed space, and the photoconductive layer 404 is covered with the cover glass 440, the glass substrate 408, and the protective member 442.

  In addition, a space surrounded by the cover glass 440, the protection member 442, and the glass substrate 408 is filled with a curable resin 444 as a filling member. As the curable resin 444, for example, a room temperature curable resin such as epoxy or silicon is used.

(Range of formation of hole injection blocking layer 402)
Here, the formation range of the hole injection blocking layer 402 will be described.

  The hole injection blocking layer 402 as an organic polymer layer has an outer edge, that is, a peripheral edge serving as a boundary with another layer is positioned at a predetermined position, so that the hole injection blocking layer 402 is formed in a predetermined range. The configuration covers the predetermined range.

  In the present embodiment, the outer edge portion of the hole injection blocking layer 402 includes the region end G1 of the image information acquisition region G from which the image information is acquired and the extraction electrode 470, among the regions irradiated with the radiation carrying the image information. It is comprised so that it may be located between. A range indicated by an arrow A in FIG. 17A is a range between the region end G1 of the image information acquisition region G and the extraction electrode 470.

  Preferably, the outer edge portion of the hole injection blocking layer 402 according to the present embodiment is outside the image information acquisition region G and has a film thickness of 10% or more of the average thickness of the flat portion of the photoconductive layer 404. It is comprised so that it may be located in the area | region which has. The flat part average film thickness of the photoconductive layer 404 is obtained by measuring the film thicknesses of nine arbitrary points in the image information acquisition region G of the photoconductive layer 404 and averaging the film thicknesses of the nine points. The film thickness was measured by observing the cross section with a microscope at a magnification of 100 times.

  Note that the range indicated by the arrow B in FIG. 17A is the range outside the image information acquisition region G and within the region having a film thickness of 10% or more of the average thickness of the flat portion of the photoconductive layer 404. is there.

  More preferably, the outer edge portion of the hole injection blocking layer 402 according to this embodiment is outside the bias electrode 401 and is in a region having a thickness of 10% or more of the average thickness of the flat portion of the photoconductive layer 404. It is comprised so that it may be located in.

  Note that a range indicated by an arrow C in FIG. 17A is a range outside the bias electrode 401 and in a region having a thickness of 10% or more of the average thickness of the flat portion of the photoconductive layer 404.

  More preferably, the outer edge portion of the hole injection blocking layer 402 is located outside the bias electrode 401 and located in a region where the slope of the end slope of the photoconductive layer 404 is 50% or less.

  The outer edge portion of the hole injection blocking layer 402 is an end slope where the gradient gradually increases from the flat portion to the outer edge of the photoconductive layer 404, and the gradient is within 50% or less, that is, the gradient is greater than 50%. Is located in a gentle range. A gradient of 50% means that, as shown in FIG. 17B, in a right triangle composed of a side along the film thickness direction of the photoconductive layer 404, a side perpendicular to the side, and a hypotenuse. This is a slope formed by the hypotenuse when the length of the side along the film thickness direction of the conductive layer 404 is 1 and the length of the side perpendicular to the side is 2. The gradient was measured by microscopic observation of the cross section at a magnification of 100 times.

  Note that the range indicated by the arrow D in FIG. 17A is the range outside the bias electrode 401 and in the region where the slope of the end slope of the photoconductive layer 404 is 50% or less.

  The photoconductive layer 404 is formed in a wider area than the bias electrode 401. The charge collection electrode 407a is formed in a region wider than the image information acquisition region G.

  Note that the outer edge portion of the hole injection blocking layer 402 according to this embodiment may be configured to be located outside the image information acquisition region G and within the region of the photoconductive layer 404.

(Operation principle of TFT radiation detector)
Next, the operation principle of the above-described TFT radiation detector 400 will be described. When the photoconductive layer 404 is irradiated with X-rays, charges (electron-hole pairs) are generated in the photoconductive layer 404. In a state where a voltage is applied between the bias electrode 401 and the Cs electrode 418, that is, in a state where a voltage is applied to the photoconductive layer 404 via the bias electrode 401 and the Cs electrode 418, charge accumulation with the photoconductive layer 404 is performed. Since the capacitor 407c is electrically connected in series, the electrons generated in the photoconductive layer 404 move to the + electrode side, and the holes move to the-electrode side. As a result, the charge storage capacitor Charge is accumulated in 407c.

  The charge stored in the charge storage capacitor 407c can be extracted to the outside from the source electrode 410 through the extraction electrode 470 by turning on the switch element 407b by an input signal to the gate electrode 411. Since the electrode wiring composed of the gate electrode 411 and the source electrode 410, the switch element 407b, and the charge storage capacitor 407c are all provided in a matrix, signals input to the gate electrode 411 are sequentially scanned to obtain the source electrode 410. By detecting the signal from each source electrode 410, X-ray image information can be obtained two-dimensionally.

Example 1
In Example 1, an electron injection blocking layer 406 made of antimony sulfide having a thickness of 2 μm is formed on the active matrix substrate 450. Next, a Se raw material containing 3% of As was formed into a film by vapor deposition to form a crystallization prevention layer 405 having a thickness of 0.15 μm. Subsequently, a Se raw material containing 10 ppm of Na was deposited by vapor deposition to form a photoconductive layer 404 made of amorphous Se having a thickness of 1000 μm.

  Next, a discharge liquid containing at least one kind of hole blocking material selected from carbon clusters or derivatives thereof and containing at least one kind of aromatic solvent represented by the general formulas (1) and (2) is used. Thus, a hole injection blocking layer 402 as an organic polymer layer was formed.

(In the general formulas (1) and (2), R1-8 represents hydrogen, halogen, or an alkyl group.)
In this example, fullerene C60 was used as the carbon cluster. The fullerene C60 used was a frontier carbon, nanom purple (C60).

  Moreover, in this example, 1.05 wt% polycarbonate resin (PCz) (Iupilon PCz-400 manufactured by Mitsubishi Gas Chemical Co., Ltd.) and 30 wt% with respect to PCz were added to o-dichlorobenzene as the aromatic solvent. The fullerene C60 was dissolved to prepare a discharge liquid.

The discharged liquid shows dilatancy. Dilatancy refers to the property of a liquid whose viscosity increases with increasing shear rate. The relationship between the shear rate of the discharged liquid and the shear viscosity was measured with a rheometer. The measurement was performed twice in the range of the shear rate of 10-1000 [s ⁻¹ ], and the average value is shown in FIG. Since the shear viscosity increases with increasing shear rate, it can be said to be dilatancy.

The exponential approximation in the graph of FIG. 21 is y = 2.2331e ^1E-05x . The shear rate applied to the ejected liquid during ejection from the inkjet head is generally said to be about 10 ⁵ [s ⁻¹ ], and the shear viscosity at that time is expected to be 6.07 [mPa · s]. On the other hand, since the shear rate after landing is considered to be 0 [s ^-1 ], the shear viscosity at that time is expected to be 2.23 [mPa · s]. Since the viscosity decreases after landing, the liquid easily spreads and is clearly suitable for forming a uniform film.

  Further, the discharge liquid has a contact angle with the photoconductive layer 404 of 45 ° or less. In this example, a discharge liquid having a contact angle with the photoconductive layer 404 of 5 ° was used.

  The discharged liquid was filled in an inkjet head SE-128 manufactured by FUJIFILM Dimatix, and discharged over a range wider than the image information acquisition region G and not on the extraction electrode 470. The solvent was evaporated with a vacuum dryer to obtain a hole injection blocking layer 402 having a thickness of 0.2 μm. Finally, Au was deposited on the inner side of the hole injection blocking layer 402 end to form a bias electrode 401 having a thickness of 0.1 μm.

  In the configuration of the present embodiment, the outer edge portion of the hole injection blocking layer 402 is located on the 1 mm image information acquisition region G side from the extraction electrode 470, and the region end G1 of the image information acquisition region G from which image information is acquired. And the extraction electrode 470.

  Thereby, the hole injection blocking layer 402 covers the image information acquisition region G of the photoconductive layer 404, so that deterioration such as crystallization in the image information acquisition region G of the photoconductive layer 404 can be suppressed, and the radiation detector 400 As a result, durability is improved. In addition, since the hole injection blocking layer 402 does not cover the extraction electrode 470, poor conduction of the extraction electrode 470 can be prevented.

(Example 2)
In Example 2, the outer edge portion of the hole injection blocking layer 402 is located 1 mm inward from the end of the bias electrode 401, is outside the image information acquisition region G, and is the average thickness of the flat portion of the photoconductive layer 404. It is comprised so that it may be located in the area | region which has a film thickness of 10% or more.

  According to the configuration of this example, the hole injection blocking layer 402 having charge selectivity has a region having a film thickness of less than 10% of the average thickness of the flat portion of the photoconductive layer 404, that is, a region having a small film thickness. Since it is not covered, creeping discharge that occurs along the hole injection blocking layer 402 hardly occurs.

(Example 3)
In Example 3, the outer edge portion of the hole injection blocking layer 402 is located at a location that is 50% of the average thickness of the flat portion of the photoconductive layer 404, outside the bias electrode 401, and on the photoconductive layer 404. It is comprised so that it may be located in the area | region which has a film thickness of 10% or more of a flat part average film thickness.

  According to the configuration of the present embodiment, since the hole injection blocking layer 402 covers the end portion of the bias electrode 401, discharge breakdown due to electric field concentration on the end portion of the bias electrode 401 can be suppressed.

Example 4
In Example 4, the outer edge of the hole injection blocking layer 402 is located 2 mm outside the end of the bias electrode 401, outside the bias electrode 401, and the slope of the end slope of the photoconductive layer 404 is 50%. It is configured to be located in the following area.

  According to the configuration of this example, the hole injection blocking layer 402 is formed in a region where the slope of the end slope of the photoconductive layer 404 is 50% or less, so that the hole injection blocking layer 402 is in a liquid state. Even when it is made of a material, no dripping occurs. If a liquid puddle due to dripping occurs, crystallization of C60 occurs and creeping discharge is liable to occur. However, in this embodiment, dripping does not occur, so creeping discharge can be suppressed.

  Note that the hole injection blocking layer 402 may have a two-layer structure, and antimony sulfide having a thickness of 0.6 μm may be stacked on an organic polymer layer containing fullerene. With this configuration, the hole blocking property can be improved.

(Configuration of optical reading radiation detector)
The present invention can also be applied to an optical reading type radiation detector, and is applied according to the configuration of the hole injection blocking layer 402 in the radiation detector 400 described above. Here, a radiation detection substrate 500 as an optical reading type radiation detector will be described.

  22A and 22B are schematic views of the radiation detection substrate 500. FIG. As shown in FIGS. 22A and 22B, the radiation detection substrate 500 is connected with a TCP 510, a reading device 512 connected thereto, and a high voltage line 514 for applying a high voltage.

  A TCP (Tape Carrier Package) 510 is a flexible wiring board on which a signal detection IC (charge amplifier IC) 511 is mounted. The TCP 510 is connected by thermocompression bonding using an ACF (Anisotropic Conductive Film).

  An extended electrode portion 519 extending from the upper electrode 518 above the detection area 516 is formed, and a high voltage line 514 is connected to the extended electrode portion 519. The detection area 516 for detecting radiation includes a lower electrode 520 for reading signals and applying a high voltage, a radiation detection layer 522 for converting radiation into charges, and an upper electrode 518 for applying a high voltage.

  The lower electrode 520 is provided on the glass substrate 536, and the radiation detection lower substrate 524 is configured by the glass substrate 536 provided with the lower electrode 520.

  The production of the radiation detection substrate 500 is roughly divided into the production of a radiation detection lower substrate 524 including the lower electrode 520, the formation of the radiation detection layer 522 and the upper electrode 518, and the connection of the high voltage line 514.

  Hereinafter, the structure of the radiation detection lower substrate 524 will be described. FIG. 23 shows a schematic structure of the radiation detection lower substrate 524. In FIG. 23, TCP510 is simplified to one channel on the left and three channels on each side for a total of 6 channels. As shown in FIG. 23, the radiation detection lower substrate 524 includes a radiation detection unit 526, a pitch conversion unit 528, and a TCP connection unit 530 as an extraction electrode.

  In the radiation detection unit 526, lower electrodes 520 for extracting signals are arranged in a stripe shape (line shape). In addition, a color filter layer 534 that partially transmits only light having an arbitrary wavelength is formed under the transparent organic insulating layer 532.

  The layer above the color filter layer 534 is referred to as a common B line 520B, and the signal S line 520S in a portion without the color filter layer 534. The B line 520B is shared outside the radiation detection unit and has a comb electrode structure. The S line 520S is used as a signal line. The width of the B line 520B is, for example, 20 μm, the width of the S line 520S is, for example, 10 μm, and the interval between the B line 520B and the S line 520S is, for example, 10 μm.

  The width of the color filter layer 534 is, for example, 30 μm. The lower electrode 520 is transparent to irradiate light from the back surface, and needs flatness to avoid breakdown due to electric field concentration when a high voltage is applied. For example, IZO or ITO is used. When IZO is used, the thickness is 0.2 μm and the flatness is about Ra = 1 nm.

  The color filter layer 534 is a photosensitive resist in which a pigment is dispersed, for example, a red resist used for an LCD color filter. In order to eliminate the level difference of the color filter layer 534, a photosensitive organic transparent insulating layer 532 such as PMMA is used.

  Further, the glass substrate 536 serving as a support member is preferably transparent and rigid, and more preferably soda lime glass. As an example of the thickness of each layer, the lower electrode 520 is 0.2 μm, the color filter layer 534 is 1.2 μm, the organic transparent insulating layer 532 is 1.8 μm, and the glass substrate 536 is 1.8 mm. The color filter layer 534 and the organic insulating layer 532 are provided only in the radiation detection unit 526, and the boundary is in the radiation detection unit 526 and the pitch conversion unit 528. For this reason, the IZO wiring is formed on the glass substrate 536 in the TCP connection portion 530 via the boundary step portion of the organic insulating layer 532.

  In the radiation detection unit 526, wiring is taken out to the left and right TCPs 510 in units of a certain number. In FIG. 23, the unit is 3 lines. An example of the number of lines is 256 lines. The line width in the radiation detection unit 526 is different from the line width in the TCP connection unit 530 and is adjusted, and the line width is adjusted in the pitch conversion unit 528 in order to route the wiring to a predetermined TCP connection position. The B line 520B is made common and similarly drawn out to the TCP connection unit 530.

  In the TCP connection unit 530, the signal S line 520S and the common B line 520B shared by the outside of the radiation detection unit are arranged. The common B line 520B is disposed outside the signal S line 520S. As an example of the number, the signal line 256 and the common line are connected to the TCP using five lines above and below. Its electrode line / space is 40 / 40um.

  In addition, an alignment mark for TCP is necessary to connect TCP with this TCP connection unit 530. Although it is desirable to form with a transparent electrode, it is difficult to recognize because it is transparent, and an alignment mark is formed using, for example, a color filter layer 534 that is a constituent member of this substrate as an opaque material.

  Next, the radiation detection layer 522 will be described. FIG. 24 is a schematic diagram schematically showing the configuration of the radiation detection substrate 500. As shown in FIG. 24, the radiation detection layer includes a recording photoconductive layer 542, a charge storage layer 544, a reading photoconductive layer 546, an electrode interface layer 548, an undercoat layer 550, and an overcoat layer 552. ing.

<Photoconductive layer for recording>
The recording photoconductive layer 542 is a photoconductive material that absorbs electromagnetic waves and generates charges, and is an amorphous selenium compound, Bi ₁₂ MO ₂₀ (M: Ti, Si, Ge), Bi ₄ M ₃ O ₁₂ (M: Ti Si, Ge), Bi ₂ O ₃ , BiMO ₄ (M: Nb, Ta, V), Bi ₂ WO ₆ , Bi ₂₄ B ₂ O ₃₉ , ZnO, ZnS, ZnSe, ZnTe, MNbO ₃ (M: Li, Na, K), PbO, HgI ₂ , PbI ₂ , CdS, CdSe, CdTe, BiI ₃ , GaAs, and the like. Of these, an amorphous selenium compound is particularly preferable.

  In the case of an amorphous selenium compound, the layer is doped with a small amount of alkali metal such as Li, Na, K, Cs, Rb between 0.001 ppm and 1 ppm, LiF, NaF, KF, CsF, RbF, etc. A small amount of fluoride of 10ppm to 10000ppm, P, As, Sb, Ge added between 50ppm to 0.5%, As doped from 10ppm to 0.5%, Cl, Br , I doped in a slight amount between 1 ppm and 100 ppm can be used.

  In particular, amorphous selenium containing about 10 ppm to 200 ppm of As, amorphous selenium containing about 0.2% to 1% of As and further containing 5 ppm to 100 ppm of Cl, and alkali metal of about 0.001 ppm to 1 ppm were contained. Amorphous selenium is preferably used.

Also, Bi ₁₂ MO ₂₀ (M: Ti, Si, Ge), Bi ₄ M ₃ O ₁₂ (M: Ti, Si, Ge), Bi ₂ O ₃ , BiMO ₄ (M: Nb, Ta, V), Bi ₂ WO ₆ , Bi ₂₄ B ₂ O ₃₉ , ZnO, ZnS, ZnSe, ZnTe, MNbO ₃ (M: Li, Na, K), PbO, HgI ₂ , PbI ₂ , CdS, CdSe, CdTe Those containing fine particles of a photoconductive substance such as BiI ₃ or GaAs can also be used.

  The thickness of the recording photoconductive layer 542 is preferably 100 μm or more and 2000 μm or less in the case of amorphous selenium. In particular, it is particularly preferably in the range of 150 μm or more and 250 μm or less for mammography, and in the range of 500 μm or more and 1200 μm or less for general photographing applications.

<Charge storage layer>
The charge storage layer 544 may be any film that is insulative with respect to the polar charge to be stored, such as an acrylic organic resin, polyimide, BCB, PVA, acrylic, polyethylene, polycarbonate, polyetherimide, or a polymer such as As ₂ S. ₃ , sulfides such as Sb ₂ S ₃ and ZnS, oxides and fluorides. Furthermore, it is more preferable to be insulative with respect to the charge of the polarity to be accumulated, and to be conductive with respect to the charge with the opposite polarity. Substances with differences are preferred.

Preferable compounds include As ₂ Se ₃ , As ₂ Se ₃ doped with Cl, Br, I from 500 ppm to 20000 ppm, and As ₂ Se ₃ Se ₂ substituted with Te to about 50% (Se _x Te _1-x ) ₃ (0.5 <x <1), As ₂ Se ₃ with Se replaced to about 50%, As _x Se _y with As concentration changed by ± 15% from As ₂ Se ₃ ( x + y = 100, 34 ≦ x ≦ 46), an amorphous Se—Te system containing 5-30 wt% Te.

  In the case of using such a substance containing a chalcogenide element, the thickness of the charge storage layer 544 is preferably 0.4 μm to 3.0 μm, more preferably 0.5 μm to 2 μm. Such a charge storage layer 544 may be formed by a single film formation or may be laminated in a plurality of times.

  As a preferable charge storage layer 544 using an organic film, a compound obtained by doping a charge transport agent with a polymer such as an acrylic organic resin, polyimide, BCB, PVA, acrylic, polyethylene, polycarbonate, or polyetherimide is preferably used. . Preferred charge transport agents include tris (8-quinolinolato) aluminum (Alq3), N, N-diphenyl-N, N-di (m-tolyl) benzidine (TPD), polyparaphenylene vinylene (PPV), polyalkylthiophene. , Polyvinylcarbazole (PVK), triphenylene (TNF), metal phthalocyanine, 4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran (DCM), liquid crystal molecules, hexapentyloxytriphenylene And a molecule selected from the group consisting of a discotic liquid crystal molecule having a central core containing a π-conjugated condensed ring or a transition metal, a carbon nanotube, and fullerene. The doping amount is set between 0.1 and 50 wt.%.

<Reading photoconductive layer>
The photoconductive layer for reading 546 is a photoconductive material that absorbs electromagnetic waves, particularly visible light, and generates electric charge. The energy gap of amorphous selenium compound, amorphous Si: H, crystalline Si, GaAs, etc. is in the range of 0.7-2.5 eV. The semiconductor substance contained in the can be used. In particular, amorphous selenium is preferable.

In the case of an amorphous selenium compound, the layer is doped with a small amount of alkali metal such as Li, Na, K, Cs, Rb between 0.001 ppm and 1 ppm, LiF, NaF, KF, CsF, RbF, etc. A small amount of fluoride of 10ppm to 10000ppm, P, As, Sb, Ge added from 50ppm to 0.5%, As doped from 10ppm to 0.5%, Cl, Br , I doped in a slight amount between 1 ppm and 100 ppm can be used.
In particular, amorphous selenium containing about 10 ppm to 200 ppm of As, amorphous selenium containing about 0.2% to 1% of As and further containing 5 ppm to 100 ppm of Cl, and alkali metal of about 0.001 ppm to 1 ppm were contained. Amorphous selenium is preferably used.

  The thickness of the photoconductive layer 546 for reading is preferably about 1 μm to 30 μm as long as it can sufficiently absorb the reading light and the electric field caused by the electric charge accumulated in the charge accumulation layer 544 can drift.

<Electrode interface layer>
The electrode interface layer 548 is laid between the recording photoconductive layer 542 and the upper electrode 518 or between the reading photoconductive layer 546 and the lower electrode 520. For the purpose of preventing crystallization, amorphous selenium with As added in the range of 1% -20%, S, Te, P, Sb, Ge added in the range of 1% to 10%, the above What added the combination of an element and another element is preferable.

Alternatively, As ₂ S ₃ and As ₂ Se ₃ having a higher crystallization temperature can also be preferably used. Furthermore, in addition to the above-mentioned additive elements for the purpose of preventing charge injection from the electrode layer, in particular, alkali metals such as Li, Na, K, Rb, Cs, LiF, NaF, KF to prevent hole injection It is also preferable to dope a molecule such as RbF, CsF, LiCl, NaCl, KCl, RbF, CsF, CsCl, CsBr in the range of 10 ppm to 5000 ppm. Conversely, in order to prevent electron injection, it is also preferable to dope a halogen element such as Cl, I, or Br, or a molecule such as In ₂ O _{3 in} the range of 10 ppm to 5000 ppm. The thickness of the interface layer is preferably set between 0.05 μm and 1 μm so as to sufficiently fulfill the above purpose.

The electrode interface layer 548, the reading photoconductive layer 546, the charge storage layer 544, and the recording photoconductive layer 542 have a substrate temperature of 25 ° C. or higher in a vacuum chamber having a degree of vacuum of 10 ⁻³ to 10 ⁻⁷ Torr. The boat or crucible containing each of the above alloys is kept at a temperature of 70 ° C. or lower and heated by resistance heating or electron beam to evaporate or sublimate the alloy or compound, and are laminated on the substrate.

When the evaporation temperatures of the alloy and the compound are greatly different, it is also preferable to control the addition concentration and the dope concentration by simultaneously heating and individually controlling a plurality of boats corresponding to a plurality of evaporation sources. For example, As ₂ Se ₃ / Amorphous selenium / LiF are put in a boat, As ₂ Se ₃ boat is 340 ° C, Amorphous selenium (a-Se) boat is 240 ° C, LiF boat is 800 ° C, and each boat By opening and closing the shutter, a layer of As10% doped amorphous selenium doped with 5000 ppm LiF can be formed.

<Underlayer>
An undercoat layer 550 can be provided between the reading photoconductive layer 546 and the lower electrode (charge collecting electrode) 520. When there is an electrode interface layer (crystallization prevention layer (A layer)) 548, it is preferably provided between the electrode interface layer 548 and the lower electrode 520. The undercoat layer 550 preferably has rectification characteristics from the viewpoint of reducing dark current and leakage current. It is preferable to have an electron blocking property when a positive bias is applied to the upper electrode 518 and a hole blocking property when a negative bias is applied.

The resistivity of the undercoat layer is preferably 10 ⁸ Ωcm or more, and the film thickness is preferably 0.01 μm to 10 μm. As a layer having an electron blocking property, that is, an electron injection blocking layer, a layer made of a composition such as Sb ₂ S ₃ , SbTe, ZnTe, CdTe, SbS, AsSe, As ₂ S ₃ or an organic polymer layer is preferable. As the organic polymer layer, a film in which NPD or TPD is mixed with a hole transporting polymer such as PVK or an insulating polymer such as polycarbonate, polystyrene, polyimide, or polycycloolefin can be preferably used.

As a layer having a hole blocking property, that is, a hole injection blocking layer, a film of CdS, CeO ₂ , or the like, or an organic polymer layer is preferable. As the organic polymer layer, a film obtained by mixing a carbon cluster such as C60 (fullerene) or C70 with an insulating polymer such as polycarbonate, polystyrene, polyimide, polycycloolefin, or the like can be preferably used.

  On the other hand, a thin insulating polymer layer can also be preferably used. For example, parylene, polycarbonate, PVA, PVP, PVB, a polyester resin, an acrylic resin such as polymethyl methacrylate is preferable. The film thickness at this time is preferably 2 μm or less, and more preferably 0.5 μm or less.

<Upper layer>
An overcoat layer 552 can be provided between the recording photoconductive layer 542 and the upper electrode (voltage application electrode) 518. When there is an electrode interface layer (crystallization prevention layer (C layer)) 548, it is preferably provided between the electrode interface layer 548 and the upper electrode 518. The overcoat layer 552 preferably has rectification characteristics from the viewpoint of reducing dark current and leakage current.

It is preferable to have a hole blocking property when a positive bias is applied to the upper electrode 518, and an electron blocking property when a negative bias is applied. The resistivity of the overcoat layer is preferably 10 ⁸ Ωcm or more, and the film thickness is preferably 0.01 μm to 10 μm.

  As the layer having electron blocking properties, that is, the electron injection blocking layer, an organic polymer layer is preferable. As the organic polymer layer, a film in which NPD or TPD is mixed with a hole transporting polymer such as PVK or an insulating polymer such as polycarbonate, polystyrene, polyimide, or polycycloolefin can be preferably used.

  As the layer having a hole blocking property, that is, a hole injection blocking layer, an organic polymer layer is preferable. As the organic polymer layer, a film obtained by mixing a hole blocking material in an insulating polymer such as polycarbonate, polystyrene, polyimide, or polycycloolefin can be preferably used.

  At least one of the hole blocking materials contained in the hole injection blocking layer 402 is preferably at least one selected from carbon clusters or derivatives thereof. Further, the carbon cluster is preferably at least one selected from fullerene C60, fullerene C70, oxidized fullerene or a derivative thereof.

  On the other hand, a thin insulating polymer layer can also be preferably used. For example, parylene, polycarbonate, PVA, PVP, PVB, a polyester resin, an acrylic resin such as polymethyl methacrylate is preferable. The film thickness at this time is preferably 2 μm or less, and more preferably 0.5 μm or less.

  Next, the upper electrode 518 and the surface protective layer 554 formed on the surface of the upper electrode 518 will be described.

<Upper electrode>
As the upper electrode 518 formed on the upper surface of the recording photoconductive layer 542, a metal thin film is preferably used. Materials include Au, Ni, Cr, Au, Pt, Ti, Al, Cu, Pd, Ag, Mg, MgAg3-20% alloy, Mg-Ag intermetallic compound, MgCu3-20% alloy, Mg-Cu metal What is necessary is just to make it form from metals, such as an intermetallic compound.

  In particular, Au, Pt, and Mg—Ag intermetallic compounds are preferably used. For example, when Au is used, the thickness is preferably 15 nm to 200 nm, more preferably 30 nm to 100 nm. For example, when an MgAg3-20% alloy is used, it is more preferable to use a thickness of 100 nm to 400 nm.

Although the preparation method is arbitrary, it is preferably formed by vapor deposition by a resistance heating method.
For example, after a metal lump is melted in a boat by a resistance heating method, the shutter is opened, vapor deposition is performed for 15 seconds, and cooling is performed once. It is formed by repeating a plurality of times until the resistance value becomes sufficiently low.

<Surface protective layer>
In order to form a latent image on the radiation detection device by irradiation, a high voltage of several kV is applied to the upper electrode 518. If the upper electrode 518 is open to the atmosphere, creeping discharge is generated, and there is a risk of electric shock of the subject. In order to prevent creeping discharge in the upper electrode 518, a surface protective layer 554 is formed on the upper surface of the electrode and subjected to insulation treatment.

  Insulation treatment requires a structure in which the electrode surface does not come into contact with the atmosphere at all, and a structure in which the electrode surface is tightly covered with an insulator. In addition, this insulator needs to have a dielectric breakdown strength exceeding the applied potential. Furthermore, it is necessary for the function of the radiation detection device to be a member that does not interfere with radiation transmission. As a material and a production method of these required covering properties, dielectric breakdown strength and radiation transmittance, vapor deposition of insulating polymer or solvent coating is preferable.

  Specific examples include a room temperature curing type epoxy resin, a polycarbonate resin, a polyvinyl butyral resin, a polyvinyl alcohol resin, an acrylic resin, and a method of forming a polyparaxylylene derivative by a CVD method. Among these, a room temperature curing type epoxy resin and polyparaxylylene are preferably formed by a CVD method, and a method of forming a polyparaxylylene derivative by a CVD method is particularly preferable. A preferable film thickness is 10 μm or more and 1000 μm or less, and more preferably 20 μm or more and 100 μm or less.

  A polyparaxylylene film can be formed at room temperature, so that an insulating film with extremely high step coverage can be obtained without applying thermal stress to the adherend, but it is chemically very stable. In general, the adhesion is often not preferred. In order to increase the adhesion with the adherend, as a treatment to the adherend before the formation of polyparaxylylene, physical, such as a coupling agent, corona discharge, plasma treatment, ozone cleaning, acid treatment, surface treatment, Chemical treatment is generally known and can be used. In particular, a polyparaxylylene film is formed after applying a silane coupling agent or a solution obtained by diluting a silane coupling agent with an alcohol or the like if necessary to at least improve the adhesion to the adherend. A method of improving the adhesion with the adherend is preferable.

  Furthermore, it is preferable to perform a moisture-proof treatment to prevent the radiation detection device from aging. Specifically, the structure is covered with a moisture-proof member. As the moisture-proof member, a resin alone such as the insulating polymer is insufficient in function, and a configuration having at least an inorganic material layer such as glass or an aluminum laminate film is effective. However, since glass attenuates radiation transmission, the moisture-proof member is preferably a thin aluminum laminate film. For example, as an aluminum laminate film generally used as a moisture-proof packaging material, there is a laminate of PET 12 μm / rolled aluminum 9 μm / nylon 15 μm.

  The thickness of aluminum is preferably 5 μm or more and 30 μm or less, and the front and rear PET thicknesses and nylon thicknesses are each preferably 10 μm or more and 100 μm or less. The X-ray attenuation of this film is about 1%, which is optimal as a member that achieves both a moisture-proof effect and X-ray transmission.

  For example, as shown in FIG. 25, the entire surface of the radiation detection device subjected to insulation treatment with polyparaxylylene 554A is covered with a moisture-proof film 554B, and the periphery of the moisture-proof film 554B is bonded and fixed to the substrate with an adhesive outside the radiation detection device region. To do. Thus, the radiation detection device is sealed with the substrate and the moisture-proof film 554B.

  At the time of this adhesion and fixation, polyparaxylylene 554A is chemically very stable, and therefore generally has poor adhesion to other members by an adhesive, but light irradiation treatment with ultraviolet light prior to adhesion is performed. The adhesion can be improved by applying. The necessary irradiation time is appropriately adjusted to the optimum time depending on the wavelength and wattage of the ultraviolet light source to be used, but it is preferably 1 to 50 W with a low-pressure mercury lamp, and the light irradiation is preferably performed for 1 to 30 minutes.

  Note that the radiation detection device according to the present embodiment uses amorphous selenium, and amorphous selenium may crystallize at a high temperature of 40 ° C. or higher, so that a latent image forming function may not be obtained. Processing is not suitable. Therefore, a room temperature curable adhesive is desirable, and a two-component mixed room temperature curable epoxy adhesive having a high adhesive strength is optimal. This epoxy adhesive is applied to the outer periphery of the radiation detection device and covered with a moisture-proof film 554B. The adhesive portion is pressed and fixed uniformly from the upper surface of the moisture-proof film 554B, and is left in this state for 12 hours or more in a room temperature environment to be cured. After the adhesive is cured, the pressure is released to complete the sealing structure.

  It supplements about a sealing structure member. When a radiation detection device is used for mammography, imaging detection with a low dose is desired in order to suppress exposure in X-ray imaging. In order to detect a change in shadow caused by low-dose irradiation, it is desirable that members other than the subject (mammo) in the path from the radiation source to the device have a high X-ray transmittance, thereby obtaining a clear image.

  An example of a preferred protective layer / sealing structure is shown in FIG. 25, but is not limited thereto. It is preferable to maintain the humidity environment of the device at 30% or less, more preferably 10% or less by forming the protective film.

<Charge extraction amplifier>
In the present embodiment, the electric charge is amplified through an amplifier and then AD converted. FIG. 26 is a block diagram showing a configuration of the charge extraction amplifier and a connection mode between the charge extraction amplifier and the image processing apparatus 150 arranged outside the radiation detection substrate 500.

  A charge amplifier IC 511 as a charge extraction amplifier is a multiplexer that multiplexes signals from a large number of charge amplifiers 633a and sample hold (S / H) 633b connected to each element 615a of the radiation detection substrate 500, and each sample hold 633b. 633c.

  The current flowing out from the lower electrode is converted into a voltage by each charge amplifier 633a, the voltage is sampled and held at a predetermined timing by the sample hold 633b, and the voltage corresponding to each element 615a sampled and held is switched in the arrangement order of the elements 615a. Are sequentially output from the multiplexer 633c (corresponding to a part of main scanning).

  The signals sequentially output from the multiplexer 633c are input to the multiplexer 631c provided on the printed circuit board 631, and further, the voltage corresponding to each element 615a is sequentially output from the multiplexer 631c so as to be switched in the arrangement order of the elements 615a. To do.

  The signals sequentially output from the multiplexer 631c are converted into digital signals by the A / D converter 631a, and the digital signals are stored in the memory 631b. The image signal once stored in the memory 631b is sent to an external image processing device 150 via a signal cable, and appropriate image processing is performed in the image processing device 150, and the image signal is uploaded to the network 151 together with shooting information. Or it is sent to a printer.

<Image acquisition sequence>
The image forming sequence of this image recording / reading system basically includes the process of irradiating recording light (for example, X-rays) while applying a high voltage and accumulating latent image charges, and irradiating the reading light after completing the application of high voltage. Then, it consists of a process of reading out the latent image charge. As the reading light L, a method of scanning the line light source 301 in the electrode direction (see FIG. 27) is optimal, but other methods are also possible.

  Furthermore, a process of sufficiently erasing the unread latent image charges can be combined as necessary. This erasing process is performed by irradiating the entire surface of the panel with erasing light. The entire surface may be irradiated at once, or line light or spot light may be scanned over the entire surface, after the reading process, and / or This is performed before the latent image accumulation process. When irradiating the erasing light, erasing efficiency can be increased by combining high voltage application. Further, by performing “pre-exposure” after applying a high voltage and before irradiating the recording light, it is possible to erase a charge (dark current charge) due to a dark current generated when a high voltage is applied.

  Furthermore, it is known that various charges are accumulated on the electrostatic recording medium before irradiation of recording light due to causes other than these. Since these residual signals affect the image information signal to be output next as an afterimage phenomenon, it is desirable to reduce them by correction.

As a method of correcting the afterimage signal, a method of adding an afterimage reading process to the above-described image recording and reading process is effective. This afterimage recording process is performed by applying a high voltage without irradiating the recording light and then reading the “afterimage” with the reading light. The afterimage signal can be corrected by subtracting it from the signal. The afterimage reading process is performed before or after the image recording reading process. Further, an appropriate erasing process can be combined before or after the afterimage reading process.

In the radiation detection substrate 500 as an optical reading type radiation detector, the upper electrode 518 corresponds to the first electrode of the present invention, and the radiation detection layer 522 having the recording photoconductive layer 542 is the photoconductive layer according to the present invention. The lower electrode 520 corresponds to the second electrode according to the present invention, the TCP connection portion 530 corresponds to the extraction electrode of the present invention, and the overcoat layer 552 corresponds to the organic polymer layer of the present invention.

  In the optical reading type radiation detection substrate 500, similarly to the radiation detector 400 described above, the overcoat layer 552 can be configured as follows.

  The overcoat layer 552 as an organic polymer layer has an outer edge portion, that is, a peripheral edge serving as a boundary with another layer is located at a predetermined position, so that the overcoat layer 552 is formed in a predetermined range. It is the structure which covers.

  In the present embodiment, the outer edge portion of the overcoat layer 552 is formed between the region end G1 of the image information acquisition region G from which the image information is acquired and the TCP connection unit 530 among the regions irradiated with the radiation carrying the image information. It is comprised so that it may be located between. A range indicated by an arrow A in FIG. 28A is a range between the region end G1 of the image information acquisition region G and the TCP connection unit 530.

  Preferably, the outer edge portion of the overcoat layer 552 according to this embodiment is outside the image information acquisition region G and has a thickness that is 10% or more of the average thickness of the flat portion of the radiation detection layer 522. Configured to be located within. The flat portion average film thickness of the radiation detection layer 522 is obtained by measuring the film thicknesses of any nine points in the image information acquisition region G of the radiation detection layer 522 and averaging the film thicknesses of the nine points. The film thickness was measured by observing the cross section with a microscope at a magnification of 100 times.

  Note that the range indicated by the arrow B in FIG. 28A is the range outside the image information acquisition region G and within the region having a film thickness of 10% or more of the flat portion average film thickness of the radiation detection layer 522. is there.

  More preferably, the outer edge portion of the overcoat layer 552 according to the present embodiment is located outside the upper electrode 518 and in a region having a thickness of 10% or more of the average thickness of the flat portion of the radiation detection layer 522. Configured to do.

  Note that a range indicated by an arrow C in FIG. 28A is a range outside the upper electrode 518 and in a region having a thickness of 10% or more of the average thickness of the flat portion of the radiation detection layer 522.

  More preferably, the outer edge portion of the overcoat layer 552 is configured to be located outside the upper electrode 518 and in the region where the slope of the end slope of the radiation detection layer 522 is 50% or less.

  The outer edge portion of the overcoat layer 552 is an end slope where the gradient gradually increases from the flat portion of the radiation detection layer 522 toward the outer edge, in a region where the gradient is 50% or less, that is, the gradient is greater than 50%. Is in a moderate range. A gradient of 50% means that, as shown in FIG. 28B, in a right triangle composed of a side along the film thickness direction of the radiation detection layer 522, a side perpendicular to the side, and a hypotenuse, This is a gradient formed by the hypotenuse when the length of the side along the film thickness direction of the detection layer 522 is 1 and the length of the side perpendicular to the side is 2. The gradient was measured by microscopic observation of the cross section at a magnification of 100 times.

  Note that the range indicated by the arrow D in FIG. 28A is the range outside the upper electrode 518 and in the region where the slope of the end slope of the radiation detection layer 522 is 50% or less.

  The radiation detection layer 522 is formed in a wider area than the upper electrode 518. Further, the lower electrode 520 is formed in a region wider than the image information acquisition region G.

  The present invention is not limited to the above-described embodiment, and various modifications, changes, and improvements can be made.

The perspective view which shows the liquid application apparatus which concerns on the 1st Embodiment of this invention. The top view which shows the surface in which the nozzle of the recording head 12 was formed. Sectional view showing the ejection element 20 Block diagram showing a control system of the liquid coating apparatus 10 A diagram schematically showing the droplet ejection shape The figure which shows the simulation result by 3D general purpose thermal fluid analysis software Flow-3D The figure which shows the simulation result by 3D general purpose thermal fluid analysis software Flow-3D The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. The perspective view which shows another embodiment of the liquid application apparatus 10. FIG. Schematic diagram showing the overall configuration of a TFT radiation detector Schematic configuration diagram showing the main parts of a TFT radiation detector Sectional view showing the structure of one pixel unit of a TFT radiation detector Plan view showing the structure of a pixel unit of a TFT radiation detector Graph showing the relationship between the shear rate and shear viscosity of the discharge liquid used to form the hole injection blocking layer in TFT radiation detectors The figure which shows schematic structure of the radiation detection board | substrate as a radiation detector of an optical reading system The figure which shows schematic structure of the lower board | substrate for radiation detection of the radiation detection board | substrate shown in FIG. Schematic diagram schematically showing the configuration of the radiation detection substrate shown in FIG. The figure which shows the sealing structure which seals the upper electrode of the radiation detection board | substrate shown in FIG. Block diagram showing the configuration of the charge extraction amplifier and the connection mode between them and an image processing device arranged outside the radiation detection substrate Schematic showing how the line light is scanned as the reading light The figure which shows the example which applied the structure of the hole-injection prevention layer in the TFT type radiation detector shown in FIG. 17 to the radiation detection board | substrate shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Liquid coating device, 12 ... Recording head, 14 ... Support plate, 16 ... Substrate, 40 ... Communication interface, 42 ... System controller, 56 ... Droplet control part, 400 ... Radiation detector, 401 ... Bias electrode (1st Electrode), 402 ... hole injection blocking layer (organic polymer layer), 404 ... photoconductive layer, 407a ... charge collection electrode (second electrode), 470 ... extraction electrode, 500 ... radiation detection substrate (radiation detector), 518 ... Upper electrode (first electrode), 522 ... Radiation detection layer (photoconductive layer), 520 ... Lower electrode (second electrode), 530 ... TCP connection (extraction electrode), 552 ... Upper coating layer (organic polymer) layer)

Claims (11)

When a droplet is ejected by a recording head having a plurality of nozzles onto a substrate placed on a support plate, the recording head and the substrate are maintained while maintaining a predetermined clearance between the recording head and the substrate. Relatively scanning the support plate with the scanning means;
Discharging columnar droplets extending in the discharge direction from the nozzle,
A liquid coating method in which a lower end of the droplet is landed on the substrate before the droplet shrinks into a spherical shape.   The liquid coating method according to claim 1, wherein the recording head and the support plate are relatively scanned so that a lower end portion of the droplet and an upper end portion of the droplet land on different positions on the substrate.   The droplet is made to land on the substrate before the droplet shrinks into a spherical shape by adjusting a shear rate when the droplet is discharged from the nozzle to give the droplet a dilatancy property. 3. The liquid application method according to 2. The liquid coating method according to claim 3, wherein the droplet has a viscosity at a shear rate of 10 ⁶ [1 / s] of 25 cP or more. A support plate on which the substrate is placed;
A recording head having a plurality of nozzles for discharging liquid droplets to the substrate placed on the support plate;
Scanning means for relatively scanning the recording head and the substrate while maintaining a predetermined clearance between the recording head and the substrate;
While the scanning means relatively scans the recording head and the substrate, a columnar droplet extending in the ejection direction is ejected from the nozzle, and before the droplet shrinks into a spherical shape, the droplet is Control means for landing on the substrate;
A liquid application apparatus comprising:   The scanning unit relatively scans the recording head and the support plate so that a lower end of the droplet and an upper end of the droplet land on different positions on the substrate. Liquid applicator.   The control means adjusts a shear rate when the droplet is ejected from the nozzle so that the droplet has dilatancy, thereby causing the droplet to land on the substrate before contracting into a spherical shape. The liquid coating apparatus according to claim 5 or 6. The liquid coating apparatus according to claim 7, wherein the droplet has a viscosity at a shear rate of 10 ⁶ [1 / s] of 25 cP or more.   The liquid coating apparatus according to claim 5, wherein the droplet has a viscosity of 25 cP or more.   The liquid coating apparatus according to claim 5, wherein a surface tension or a dynamic surface tension of the droplet is 10 mN / m or less. A first electrode through which radiation carrying image information is transmitted;
A photoconductive layer that generates a charge when irradiated with the radiation transmitted through the first electrode;
A second electrode that is provided on a side opposite to the side on which the first electrode is provided with respect to the photoconductive layer, and collects charges generated by the photoconductive layer;
An organic polymer layer provided between the photoconductive layer and the first electrode;
A method of manufacturing a radiation detector comprising:
The radiation detector manufacturing method which forms the said organic polymer layer using the liquid application method of any one of Claim 1 to 4.

Images