JP2008008741A - Scintillator plate for radiation, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scintillator plate for radiation having an excellent extracting efficiency of emission with radiation and having a scintillator crystal having an excellent moisture resistance, and also to provide its manufacturing method. <P>SOLUTION: The scintillator plate comprises: a phosphor layer 3 of columnar crystals formed on a substrate 2 and emitting light by irradiation with radiation; and a protective layer formed on the layer 3. The Cs-F bond is formed on the surface of the phosphor layer 3 by introducing a carrier gas of Ar carrying a fluorine solvent HFE to form a phosphor layer 8. Then, polyparaxylylene is deposited to form the protective layer. The surface of the phosphor layer and the protective layer are disposed in contact with each other. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a radiation scintillator plate used when forming a radiation image of a subject, and more particularly to a radiation scintillator plate having a phosphor layer using Cs as a base and a radiation image detector using the radiation scintillator plate.

  Conventionally, radiographic images such as X-ray images have been widely used for diagnosis of medical conditions in the medical field. In particular, intensifying screen-film radiographic images are still used in medical sites around the world as imaging systems having both high reliability and excellent cost performance.

  However, these pieces of image information are so-called analog image information, and free image processing and instantaneous electric transmission cannot be performed like the digital image information that has been developed in recent years.

  In recent years, digital radiographic image detection apparatuses represented by computed radiography (CR), flat panel type radiation detectors (FPD) and the like have appeared. In these, since a digital radiographic image can be directly obtained and an image can be directly displayed on an image display device such as a cathode tube or a liquid crystal panel, it is not always necessary to form an image on a photographic film. As a result, these digital X-ray image detection devices reduce the need for image formation by the silver halide photography method, and greatly improve the convenience of diagnosis work in hospitals and clinics.

  Computed radiography (CR) is currently accepted in the medical field as one of the digital technologies for X-ray images.

  However, the image quality level of the screen / film system has not been reached due to insufficient sharpness and insufficient spatial resolution. Further, as a new digital X-ray imaging technique, for example, a paper by El E. Antonuk on the magazine SPIE, Vol. 32, 1997, “Development of a High Resolution, Active Matrix, Flat-Panel Image with Enhanced Fil” etc. A flat plate X-ray detector (FPD) using a thin film transistor (TFT) described in 1) has been developed.

  The flat panel X-ray detector (FPD) is characterized in that the device is smaller than the CR and the image quality at a high dose is excellent. However, on the other hand, due to the electrical noise of the TFT and the circuit itself, the signal-to-noise ratio has been reduced in low-dose imaging, and the image quality level has not been reached.

  A scintillator plate made of an X-ray phosphor having the property of emitting light by radiation is used to convert the radiation into visible light. In order to improve the S / N ratio in low-dose imaging, it is necessary to use a scintillator plate with high luminous efficiency.

  In general, the light emission efficiency of the scintillator plate is determined by the thickness of the phosphor layer and the X-ray absorption coefficient of the phosphor. The thicker the phosphor layer, the more scattered the emitted light in the phosphor layer. Occurs and sharpness decreases. Therefore, when the sharpness necessary for the image quality is determined, the film thickness is determined.

  Among these, cesium iodide (CsI) has a relatively high rate of change from X-rays to visible light, and phosphors can be easily formed into a columnar crystal structure by vapor deposition. Therefore, it was possible to increase the thickness of the phosphor layer.

  However, since the luminous efficiency is low only with CsI, a mixture of CsI and sodium iodide (NaI) at an arbitrary molar ratio is activated on the substrate by vapor deposition as in, for example, Japanese Patent Publication No. 54-3560. It is deposited as cesium fluoride (CsI: Na) and annealed as a subsequent process to improve the visible conversion efficiency and is used as an X-ray phosphor.

  Recently, as shown in Patent Document 1, for example, CsI is deposited by evaporation, such as indium (In), thallium (Tl), lithium (Li), potassium (K), rubidium (Rb), sodium (Na), etc. An X-ray phosphor manufacturing method for forming an activation material by sputtering has been devised. However, the luminous efficiency is still insufficient, and further improvement is desired.

In addition, CsI columnar crystals have a problem of low deliquescence, and in order to prevent this, a form in which CsI is directly covered with polyparaxylylene is disclosed in Patent Document 2.
JP 2001-59899 A JP 2000-9845 A

  An object of the present invention is to provide a radiation scintillator plate excellent in the extraction efficiency of light emission by radiation and excellent in moisture resistance of scintillator crystals, and a method for producing the same.

  The above object of the present invention is achieved by the following configurations.

  1. A scintillator plate for radiation in which a phosphor layer that emits light when irradiated on a substrate and a protective layer formed on the phosphor layer has a Cs-F bond on the surface of the phosphor layer, and the phosphor A scintillator plate for radiation, wherein the surface of the layer is in contact with the protective layer.

  2. 2. The main component of the phosphor layer is a CsI columnar crystal, and at least one activator selected from In, Tl, K, Rb, Na and Eu is added as an activator. Scintillator plates for radiation.

3. 3. The radiation scintillator plate according to 1 or 2 above, wherein the protective layer is composed of at least one film selected from a polyparaxylylene film, a SiO ₂ film, a SiN film, or a SiON film.

4). The protective layer is composed of a laminated film of at least one transparent film selected from SiO ₂ film, SiN film or SiON film and a polyparaxylylene film, and a transparent inorganic film or polyparaxylylene is formed in the gap between the columnar crystals. The scintillator plate for radiation according to any one of 1 to 3 above, wherein a film does not enter.

  5. The method of manufacturing a scintillator plate for radiation according to any one of 1 to 4, wherein after the CsI vapor deposition step, a fluorine-based solvent gas is heated in a reduced pressure atmosphere to form a Cs-F bond. Thereafter, the fluorine-based solvent gas is exhausted from the inside of the apparatus to form a high vacuum, and then the protective film is vapor-phase grown.

6). 6. The method for producing a scintillator plate for radiation according to 5, wherein the protective film is any one transparent film selected from a polyparaxylylene film, a SiO ₂ film, a SiN film, and a SiON film.

7). A step of depositing a protective film made of any one of transparent films selected from SiO ₂ film, SiN film, and SiON film by vapor phase growth so that the protective film does not enter the gap between the columnar crystals; 7. The method for producing a scintillator plate for radiation according to 5 or 6, wherein the method comprises a step of depositing polyparaxylylene.

  That is, as a result of intensive studies to improve the luminance, the present inventors have found that the light emission efficiency of the CsI crystal is greatly improved by the presence of a small amount of CsF crystal on the surface of the CsI crystal. Further, in order to form CsF on the surface of the CsI crystal, a method of performing a heat treatment in a gas atmosphere in which a fluorine-based solvent gas is vaporized or in a gas containing fluorine is found after forming a phosphor into a columnar crystal structure by vapor deposition. It was.

When this treatment is performed, the concentration of the halogen element F increases on the surface of the CsI crystal. F reacts with H ₂ O in the air to become HF, which may corrode Al which is a substrate material of the scintillator plate.

  There is also a problem that ionization is easier than that of I, adsorbs on the surface of Al, and corrosion tends to proceed due to a battery reaction.

  The present inventors have found that the problem of Al corrosion can be improved by subjecting the above-described CsI F treatment and deposition of a protective film such as polyparaxylylene to continuous treatment in vacuum.

  The radiation scintillator plate according to the present invention and the method for producing the same have an effect of being excellent in extraction efficiency of light emission by radiation and excellent in moisture resistance of scintillator crystals.

  The manufacturing method of the scintillator plate for radiation of Claim 5, 6, 7 is said invention, The scintillator plate for radiation formed by this was described in Claim 1, 2, 3.

  Further, when polyparaxylylene is deposited as a single film, there is a problem that polyparaxylylene enters the gap portion of the CsI columnar crystal because the step coverage is good by chemical vapor deposition.

Polyparaxylylene has a refractive index of 1.639, which is larger than 1 of air and close to the refractive index of CsI of 1.807. Therefore, light easily leaks from the CsI columnar crystal to the gap, and the light confinement effect is insufficient. It is easy to become. The present inventors have poor step coverage, the refractive index is temporarily block the gap portion of the CsI columnar crystals of SiO ₂ closer to the air and 1.46, so that polyparaxylylene from entering between CsI columnar crystals Thus, the light extraction efficiency is not deteriorated.

  The manufacturing method of the scintillator plate for radiation of Claim 8 is said invention, The scintillator plate for radiation formed by this was described in Claim 4.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, the present invention is not limited to these illustrated examples.

  In FIG. 1A, an aluminum plate of 1 mm or less is used as the substrate 2 as a metal having a high X-ray transmittance. Examples of the phosphor 3 include CsBr and CsCl in addition to CsI.

  Further, the phosphor 3 based on Cs described above may be any mixed crystal.

  The activator material applicable to the present invention may be any known material, but can be arbitrarily selected according to required characteristics such as emission wavelength. Specific examples include compounds such as In, Tl, Li, K, Rb, Na, Eu, Cu, Ce, Zn, Ti, Gd, and Tb, but are not limited thereto.

The inventors of the present invention have found that the luminous efficiency of the phosphor layer 3 can be greatly improved by causing a trace amount of Cs—F bonds to be present on the surface of the crystal constituting the phosphor 3. As a method for forming a Cs-F bond, introduction of F into the surface of CsI having an activator by a known vapor deposition method is performed at a temperature of about 200 ° C., and a CsI crystal is fluorinated in a reduced pressure atmosphere (for example, HFE (hydrofluoroether) ) Exposure to atmosphere or exposure to fluorine gas (CHF ₃ etc.) atmosphere. (See FIG. 1 (b) and FIG. 3)
Here, if the total amount of CsF formed on the crystal surface is 10 ppm or more with respect to the base CsI, the effect of the present invention can be obtained, but it is preferably 20 ppm or more. The total amount of CsF formed on the crystal surface can be arbitrarily adjusted depending on the heating time and heating temperature. The heating temperature is preferably 80 ° C. or higher and 350 ° C. or lower from the viewpoint of work safety. The effect of F is considered to be reasons such as vacancy filling on the crystal surface and photoelectrons are easily emitted due to the high electronegativity of F.

  As the fluorine-based solvent used at this time, HFE (hydrofluoroether) which is a substitute material for chlorofluorocarbon is advantageous from the viewpoint of environmental suitability and harmfulness to living bodies. Examples of HFE include Novec (registered trademark) HFE-7100, 7100DL, and 7200 manufactured by Sumitomo 3M Limited. These commercially available HFE can be suitably used as a halogenated solvent that can be used in the heating step.

  When F is introduced into Cs in this way, if the residual moisture is on the CsI surface having Cs-F, H and F react to become HF, causing a problem of corrosion of the Al substrate. In addition, F is ionized and adheres to the surface of Al, and the problem arises that the Al surface corrodes due to the battery effect. In contrast, in the present invention, as shown in FIGS. 2 (a) and 2 (b), after forming a Cs-F bond, the surface is not exposed to the atmosphere, and polyparaxylylene 11 is used as a protective film continuously in a vacuum. By making the gas phase volume, the intrusion of moisture can be suppressed and the Al substrate can be protected from corrosion.

  The completed scintillator plate for radiation is shown in FIG. A columnar crystal of CsI: Tl phosphor 3 exists on the substrate 2, and a CsI layer 8 having a Cs-F bond is formed on the surface thereof.

  Polyparaxylylene 11 is present as a protective film in contact with this layer 8. Since the polyparaxylylene 11 is deposited by a vapor deposition polymerization reaction, the step coverage is good because it is a deposition method through a chemical reaction, and the structure in which the polyparaxylylene 11 enters between the columnar structures of the CsI: Tl phosphor. It becomes.

  In this case, since the refractive index of polyparaxylylene is 1.639, which is larger than 1 of air and close to the refractive index of CsI, it is close to 1.807. Light tends to leak, and the light confinement effect tends to be insufficient. For this reason, the luminance obtained when a certain amount of X-rays is incident on the scintillator plate for radiation is improved by the formation of Cs-F bonds. There is a problem that it is lost due to a decrease in the confinement effect.

  A radiographic image detector formed using the radiation scintillator plate of the present invention will be described with reference to FIG. The radiation scintillator plate 20 of the present invention shown in FIG. 3 and the light receiving element panel 13 are arranged in the housing 12 so as to face the scintillator plate. There may be nothing between the scintillator plate 20 for radiation and the light receiving element panel 13 as shown in FIG. 4, for example, an optical material such as a UV cured film having a light transmittance of 90% or more and a refractive index close to 1. A connecting material may be interposed.

  The operation of the radiation image detector formed using the radiation scintillator plate of the present invention will be described. First, radiation such as X-rays enters from the substrate side of the radiation scintillator plate 20. The CsI: Tl phosphor 3 in the radiation scintillator plate 20 and CsI8 having a Cs-F bond absorb the energy of the radiation, and visible light corresponding to the intensity is emitted as fluorescence. This visible light is absorbed by the light receiving element panel 13 and detected as a photocurrent in the light receiving element panel. With such a mechanism, an image corresponding to the intensity of X-rays can be obtained. The radiation image detector having such a structure is used for medical and nondestructive X-ray inspections.

The second best mode for carrying out the present invention will be described below with reference to the drawings. However, the scope of the present invention is not limited to these illustrated examples. The process is the same up to the point where a very small amount of Cs-F bond is present on the surface of the crystal constituting phosphor 3. In the present embodiment, the Cs—F bond is formed by placing a CsI: Tl phosphor in a gas CHF ₃ atmosphere containing fluorine at about 200 ° C. Here, if the total amount of CsF formed on the crystal surface is 10 ppm or more with respect to the base CsI, the effect of the present invention can be obtained, but it is preferably 20 ppm or more. Further, the total amount of CsF formed on the crystal surface can be arbitrarily adjusted by the heating time and the heating temperature. Although it is an effect of F, it is considered that the luminous efficiency of the CsI: Tl phosphor is increased because photoelectrons are likely to be emitted because the vacancy filling of the crystal surface and the electronegativity of F are high. The gas containing fluorine used at this time may be a gas other than CHF ₃ , such as NF ₃ .

  When F is introduced into Cs in this way, if the residual moisture is on the CsI surface having Cs-F, H and F react to become HF, causing a problem of corrosion of the Al substrate. In addition, F is ionized and adheres to the surface of Al, causing a problem that the Al surface corrodes due to the battery effect.

On the other hand, in the present invention, as shown in FIGS. 5A and 5B, after forming the Cs-F bond, the surface is not exposed to the atmosphere, and SiO ₂ is sputter deposited continuously as a protective film in vacuum. . Sputter deposition is physical vapor deposition and has a lower step coverage than chemical vapor deposition using chemical reaction. Therefore, the SiO ₂ film does not enter the columnar gap portion of the CsI crystal.

  Next, as shown in FIG. 7, by making the gas phase volume of polyparaxylylene 11, the intrusion of moisture can be suppressed and the Al substrate can be protected from corrosion.

  In this example, since polyparaxylylene is not present in the gaps between the columnar crystals, the light guiding effect near the crystal surface can be maintained, and a radiation scintillator panel with high brightness can be obtained.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, the embodiment of this invention is not limited to this.

  According to the following method, the radiation scintillator panel of Example 1 and the actual example 2 was produced.

Example 1
As shown in FIG. 1A, an aluminum substrate 2 having a thickness of 1 mm is set on a substrate holder 1 of a vapor deposition apparatus, and the resistance heating crucible 5 is made of CsI: Tl (CsI: TlI = 1: 0.3 mol%) as a vapor deposition material. The space between the substrate holder 1 and the resistance heating crucible 5 was adjusted to 400 mm. Subsequently, the inside of the apparatus is evacuated by the vacuum pump 6. After introducing Ar gas and adjusting the degree of vacuum to 0.5 Pa, the substrate holder 1 held at 150 ° C. is rotated at a speed of 10 rpm. Next, the resistance heating crucible was heated to deposit the phosphor, and the deposition was terminated when the thickness of the phosphor layer reached 500 μm.

  Next, as shown in FIG. 1B, HFE vaporized by bubbling by the HFE creating apparatus 7 is introduced into the vapor deposition apparatus using Ar gas as a carrier. The pressure remains at 0.5 Pa. By holding in this state for 30 minutes, a CsI layer 8 having a Cs-F bond is formed on the surface of the CsI: Tl phosphor.

  Next, as shown in FIGS. 2A and 2B, evacuation is performed once in the vapor deposition apparatus. Next, polyparaxylylene is deposited as shown in FIG. Diparaxylylene is vaporized in the vaporizing chamber 9 at 175 ° C. and 133 Pa.

  Next, thermal decomposition is performed in the thermal decomposition chamber 10 to diradical paraxylene under conditions of 680 ° C. and 67 Pa. Next, it is polymerized at 35 ° C. and 13 Pa in a vapor deposition chamber to form a polyparaxylylene film. When exhausting, cool at -70 ° C. and 1.3 Pa.

  This film is characterized by being insoluble in all organic solvents at 150 ° C. or less and having resistance to most acid, alkali and other corrosive liquids.

  Further, it has a feature of low permeability of water vapor and gas, and is suitable for a protective film of CsI: Tl that is originally deliquescent. Here, polyparaxylylene is polyparaxylylene, polymonochloroparaxylylene, polydichloroparaxylylene, polytetrachloroparaxylylene, polyfluoroparaxylylene, polytetrachloroparaxylylene, polyfluoroparaxylylene. Len, polydimethylparaxylylene, polydiethylparaxylylene, and the like.

  However, in the present invention, since F, which is a halogen element that easily causes corrosion, is contained, the element that causes corrosion already exists before polyparaxylylene is deposited. Therefore, after the process of forming the Cs-F layer, polyparaxylylene deposition is performed in a continuous process in vacuum to prevent moisture from adsorbing to CsI having a Cs-F bond, thereby generating HF and ionizing F. By preventing this, corrosion of the substrate 2 and dissolution of CsI: Tl phosphor 3 and CsI8 having a Cs-F bond can be prevented.

  The above is the manufacturing method of the scintillator plate for radiation of this invention, and is the content of Claims 5 and 7. The radiation scintillator plate formed thereby is shown in FIG.

  This embodiment corresponds to claims 1, 2, and 3. Moreover, the example which comprised the radiographic image detector using the scintillator plate for radiation of this invention is shown in FIG.

(Moisture resistance evaluation by luminance measurement)
The radiation scintillator plate obtained by the present invention is set on a 10 cm × 10 cm CMOS flat panel (Radicon X-ray CMOS camera system Shad-o-Box 4KEV), and the luminance is calculated from the 12-bit output data. did. X-rays having a tube voltage of 80 kVp were irradiated from the back surface (surface on which the phosphor layer was not formed) of each sample through a lead MTF chart, and image data was detected by a CMOS flat panel in close contact with the scintillator and recorded on a hard disk. The recording was then analyzed with a computer to determine the brightness of the X-ray image. Placed in an environment of 40 ° C. and 90%, the time when the luminance dropped to 80% of the initial value was measured and defined as the life and compared. Then, it was found that the plate on which the polyparaxylylene layer was continuously deposited in a vacuum had a life three times longer than the plate on which the CsI surface was once exposed to air and then the polyparaxylylene layer was deposited.

Example 2
FIG. 5A is the same process as FIG. In this embodiment, as shown in FIG. 5B, a gas containing F, for example, CHF ₃ is introduced into the vapor deposition apparatus from the gas introduction apparatus 14 (which may be considered as only piping from a cylinder). An inert gas such as Ar may be added as necessary. The pressure is 0.1 Pa. By holding in this state for 30 minutes, a CsI8 layer having a Cs-F bond is formed on the surface of the CsI: Tl phosphor.

Next, as shown in FIG. 6A, evacuation is performed once in the vapor deposition apparatus. Next, as shown in FIG. 6B, a SiO ₂ film is sputter-deposited on the CsI: Tl crystal using the SiO ₂ target 17. Here, a pressure of 1 Pa, a substrate temperature of 150 ° C., and a target input RF power of 150 W are used. Since the sputtered SIO ₂ film has poor step coverage, the gap between the columnar crystals of the CsI: Tl crystal 3 cannot be filled.

  Next, 20 μm of polyparaxylylene is deposited as shown in FIG. The deposition conditions are the same as those described with reference to FIG. The polyparaxylylene film is insoluble in all organic solvents at 150 ° C. or lower, and has a feature that it is resistant to most acid, alkali and other corrosive liquids.

  In addition, it has a feature of low permeability of water vapor and gas, and is suitable as a protective film of CsI: Tl that is originally deliquescent. Here, polyparaxylylene is polyparaxylylene, polymonochloroparaxylylene, polydichloroparaxylylene, polytetrachloroparaxylylene, polyfluoroparaxylylene, polytetrachloroparaxylylene, polyfluoroparaxylylene. Len, polydimethylparaxylylene, polydiethylparaxylylene, and the like.

  In the present invention, polyparaxylylene for preventing corrosion is deposited. However, polyparaxylylene has a high step coverage, and therefore enters the gap of the CsI: Tl crystal. In this case, since the refractive index of polyparaxylylene is 1.639, which is larger than 1 of air and close to the refractive index of CsI, it is close to 1.807. Light tends to leak, and the light confinement effect tends to be insufficient.

  For this reason, the luminance obtained when a certain amount of X-rays is incident on the scintillator plate for radiation is improved by the formation of Cs-F bonds. There is a problem that it is lost due to a decrease in the confinement effect.

Therefore, in the present invention, the SiO ₂ film having a poor step coverage is first sputtered to close the opening of the gap portion to secure the light confinement effect. Since the refractive index of SiO ₂ is about 1.46 at the emission wavelength of CsI: Tl, which is smaller than that of polyparaxylylene, the light extraction effect is also excellent. In addition, since SiON has a value of about 1.46 to 2.2 and SiN has a value of about 2 to 2.2, in these films, the light extraction efficiency may be lower than in the case of SiO ₂ , but polyparaxylylene It is considered that there is an effect to prevent the spread of light (degradation of resolution) that occurs in the gaps between the columnar crystals. Further, if the composition of O and N is adjusted with SiON so that the refractive index is intermediate between CsI and polyparaxylylene (1.807 + 1.639) /2=1.723, it is considered that the deterioration of the light extraction efficiency can be prevented. It is done.

  A film having a low step coverage does not sufficiently surround the film at corners or the like, and cannot function sufficiently as a protective film. Therefore, in the present invention, polyparaxylylene is deposited in the same manner as in FIG. 2B in FIG.

(Moisture resistance evaluation by luminance measurement)
The radiation scintillator plate obtained by the present invention was set on a CMOS flat panel (X-ray CMOS camera system Shad-o-Box 4KEV manufactured by Radicon) having a size of 10 cm × 10 cm, and the luminance was calculated from 12-bit output data. X-rays having a tube voltage of 80 kVp were irradiated from the back surface (surface on which the phosphor layer was not formed) of each sample through a lead MTF chart, and image data was detected by a CMOS flat panel in close contact with the scintillator and recorded on a hard disk.

  The recording was then analyzed with a computer to determine the brightness of the X-ray image.

  First, the luminance of the scintillator plate for radiation of this example was compared with that of the scintillator plate prepared in Example 1, and it was found that the present invention was higher by 2.4, 2.2, and 10%. Next, in an environment of 40 ° C. and 90%, the time when the luminance dropped to 80% of the initial value was measured and defined as the life and compared. Then, there was no difference in lifetime between the present example and the scintillator plate produced in Example 1.

  The above is the manufacturing method of the scintillator plate for radiation of this invention, and is the content of Claims 6 and 8. The radiation scintillator plate thus formed is shown in FIG. This embodiment supports claims 1, 2, and 4.

It is process sectional drawing which shows an example of the radiation scintillator plate of this invention. It is process sectional drawing which shows an example of the radiation scintillator plate of this invention. It is sectional drawing which shows an example of the radiation scintillator plate of this invention. It is sectional drawing which shows an example of the radiographic image detector of this invention. It is process sectional drawing which shows the other example of the radiation scintillator plate of this invention. It is process sectional drawing which shows the other example of the radiation scintillator plate of this invention. It is process sectional drawing which shows the other example of the radiation scintillator plate of this invention. It is sectional drawing which shows the other example of the radiation scintillator plate of this invention.

DESCRIPTION OF SYMBOLS 1 Substrate holder 2 Substrate 3 CsI: Tl phosphor 4 Vacuum chamber 5 Resistance heating crucible 6 Vacuum pump 7 HFE vapor preparation device 8 CsI having Cs-F bond
9 Vaporization chamber 10 Pyrolysis chamber 11 Polyparaxylylene 12 Case 13 Light receiving element panel 14 Gas introduction device 15 SiO ₂
20 Radiation scintillator plates

Claims (7)

A scintillator plate for radiation in which a phosphor layer that emits light when irradiated on a substrate and a protective layer formed on the phosphor layer has a Cs-F bond on the surface of the phosphor layer, and the phosphor A scintillator plate for radiation, wherein the surface of the layer is in contact with the protective layer. The main component of the phosphor layer is a CsI columnar crystal, and at least one activator selected from In, Tl, K, Rb, Na and Eu is added as an activator. The scintillator plate for radiation as described. The radiation scintillator plate according to claim 1 or 2, wherein the protective layer is composed of at least one film selected from a polyparaxylylene film, a SiO ₂ film, a SiN film, and a SiON film. The protective layer is composed of a laminated film of at least one transparent film selected from SiO ₂ film, SiN film or SiON film and a polyparaxylylene film, and a transparent inorganic film or polyparaxylylene is formed in the gap between the columnar crystals. The scintillator plate for radiation according to any one of claims 1 to 3, wherein a film does not enter. The method for manufacturing a scintillator plate for radiation according to any one of claims 1 to 4, wherein a Cs-F bond is formed by heating a fluorine-based solvent gas in a reduced-pressure atmosphere after the CsI vapor deposition step. Then, after exhausting the fluorine-based solvent gas from the inside of the apparatus to form a high vacuum, the protective film is vapor-phase grown, and the method for producing a scintillator plate for radiation is characterized by the following. Protective film is a polyparaxylylene film, SiO ₂ film, SiN film, the manufacturing method of the scintillator plate according to claim 5, characterized in that any one of the transparent film selected from the SiON film. A step of depositing a protective film made of any one of transparent films selected from SiO ₂ film, SiN film, and SiON film by vapor phase growth so that the protective film does not enter the gap between the columnar crystals; The method for producing a scintillator plate for radiation according to claim 5 or 6, comprising a step of depositing polyparaxylylene.

Images