JP2006292546A - Manufacturing method of phosphor layer, and radiological image conversion panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a phosphor layer for a radiological image conversion panel capable of improving uniformity of the thickness of the phosphor layer and the flatness of its surface without damaging a columnar structure of the phosphor layer comprising a columnar crystal, and the radiological image conversion panel having the phosphor layer. <P>SOLUTION: This manufacturing method of the phosphor layer for the radiological image conversion panel has a film forming process for forming the phosphor layer comprising the columnar crystal on a substrate by a vapor-phase sedimentation method, and a grinding process for grinding the surface of the formed phosphor layer. The grinding process is a process for grinding the surface of the phosphor layer as much as a prescribed thickness by moving relatively a grinding material and the substrate in the state where the grinding material is disposed at a prescribed interval with a prescribed reference plane. In the manufacturing method of the phosphor layer is characterized by acquiring a desired value of the flatness on the surface of the phosphor layer by performing the grinding process in the divided state into a plurality of times. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a phosphor layer manufacturing technique suitable for use in a radiation image conversion panel, and a radiation image conversion panel having the phosphor layer, and more specifically, from columnar crystals manufactured by a vapor deposition method. And a radiation image conversion panel having the phosphor layer.

  When irradiated with radiation (X-rays, α-rays, β-rays, γ-rays, electron beams, ultraviolet rays, etc.), a part of this radiation energy is accumulated, and then irradiated with excitation light such as visible light, Phosphors that exhibit stimulated luminescence according to the stored energy are known. This phosphor is called a storage phosphor (stimulable phosphor) and is used for various applications such as medical applications.

  As an example, radiation image information using a sheet (phosphor sheet) having a layer containing this type of stimulable phosphor (that is, a phosphor layer) processed into a panel (called a radiation image conversion panel) A recording / reproducing system is known, and has been put into practical use as, for example, FCR (Fuji Computed Radiography).

  In this system, radiographic image information of a subject such as a human body is recorded on the phosphor sheet, and after recording, the phosphor sheet is two-dimensionally scanned with excitation light such as laser light to generate stimulated emission light. The photoluminescence light is photoelectrically read to obtain an image signal, and an image reproduced based on the image signal is recorded on a recording material such as a photographic material or a display device such as an LCD or CRT. Is output as a visible image.

  As a method for producing such a phosphor sheet, a method of forming a phosphor layer on a substrate by vapor deposition or sputtering, which is a vapor deposition method, is known (Japanese Patent No. 2789194, Japanese Patent Laid-Open No. 5-249299). Etc.) The phosphor layer formed by vapor deposition has few impurities because it is formed in a vacuum, and contains almost no components other than the storage phosphor such as a binder. It has an excellent feature that its luminous efficiency is very good.

In general, vacuum deposition is used as a method for forming a thin film in various fields such as coating of optical parts, manufacture of magnetic recording media and electronic displays. In the film formation by vapor deposition in these, in most cases, the thickness of the film to be formed is 1 μm or less, and at most about 3 μm.
On the other hand, the phosphor layer of the phosphor sheet formed by vacuum deposition needs to have a thickness of 200 μm or more, usually about 500 μm, even if it is thin, and a thickness of 1000 μm.

  The present applicant has previously proposed a method or an apparatus for manufacturing a phosphor sheet that can be suitably used for forming such a phosphor layer (forming a phosphor film) (for example, Japanese Patent Application No. 2002-4291). (See Japanese Patent Application Laid-Open No. 2003-201555) and 2002-19631 (Japanese Patent Application Laid-Open No. 2003-221661). These techniques are related to a phosphor sheet manufacturing technique by so-called binary vapor deposition. In the vacuum chamber, evaporation means for heating and evaporating the phosphor film-forming material and heating the activator film-forming material are heated. The present invention proposes an apparatus provided with an evaporating means for evaporating and a substrate holding / rotating means.

  By the way, in the above-mentioned FCR system, as described above, a radiation image is recorded on the phosphor sheet, and after the recording, the phosphor sheet is scanned two-dimensionally with excitation light such as a laser beam, thereby generating a photostimulable light. The stimulated emission light is photoelectrically read to obtain an image signal, which is output to a recording material such as a photographic photosensitive material or a display device such as an LCD or CRT as a visible image of a radiographic image of the subject.

The problem here is that when reading the radiation image information from the above-mentioned phosphor sheet, the distance between the reading head (light receiving portion) and the phosphor layer surface on the phosphor sheet needs to be uniform. That is.
However, when the thick phosphor layer as described above is formed by vapor deposition, especially when a large-sized phosphor sheet having the thick phosphor layer as described above is manufactured, the entire surface is uniform. It was difficult to form a thin film, and the limit was to keep the film thickness distribution within about ± 3%.

  When reading the image information recorded on the phosphor sheet, as shown in FIG. 7, a light beam (not shown) is applied to the phosphor layer 94 formed on the substrate 92 of the phosphor sheet 90 from a light beam irradiation means (not shown). Excitation light) is emitted, and the generated stimulated emission light is read by the line CCD sensor 96. At this time, the distance A between the line CCD sensor 96 and the surface of the phosphor sheet 90 is about 100 μm.

  On the other hand, if the thickness of the phosphor layer 94 is about 500 μm, the variation width B of the thickness of the phosphor layer 94 is about 30 μm because the above-mentioned thickness distribution is about ± 3%. Therefore, since the distance A between the line CCD sensor 96 and the surface of the phosphor sheet 90 varies greatly depending on the location, there is a problem that the image is blurred. For this reason, it is desirable to make the fluctuation range of the film thickness of the phosphor layer 94 as small as possible.

  In addition, depending on the film formation conditions, a protrusion-like surface roughness called splash (bumping) may occur during film formation due to the influence of foreign substances contained in the material. When such a splash occurs, scattering of excitation light or stimulated emission light at the time of reading by the reading head occurs, and deterioration of information at the time of reading (image blurring or the like) also occurs.

  The present applicant previously polished a phosphor layer (evaporated phosphor layer) formed by vapor deposition according to Japanese Patent Application No. 2002-236306 (see Japanese Patent Application Laid-Open No. 2004-77236), and then increased the thickness thereof. By uniforming, the non-uniformity of the distance between the read head and the phosphor layer at the time of reading by the read head is eliminated, and due to the scattering of excitation light or stimulated emission light at the time of reading as described above. A method of manufacturing a vapor-deposited phosphor layer that can prevent deterioration of information (such as image blur) has been proposed.

  Moreover, although the prior application shows an example of polishing a phosphor layer formed using a rotary evaporation type apparatus after film formation, the applicant of the present application separately described in Japanese Patent Application No. 2004-346832, In the method for manufacturing a vapor deposition phosphor layer according to the present invention, a linear transport type vapor deposition apparatus is proposed, and the phosphor layer formed by using this linear transport type vapor deposition apparatus can also be polished after film formation. By making the thickness uniform, it is possible to realize a method for producing a vapor-deposited phosphor layer having good characteristics.

JP 2004-77236 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to be able to prevent deterioration of information at the time of reading radiation image information from a phosphor sheet. More specifically, the thickness uniformity of the phosphor layer and the surface of the phosphor layer having a thickness of about 500 μm, or about 1000 μm when thick, without damaging the columnar structure of the phosphor layer made of columnar crystals. A method for producing a phosphor layer for a radiation image conversion panel having excellent optical characteristics, which can realize the uniformity of the distance between the reading head and the phosphor layer by improving the flatness, and the phosphor layer. The object is to provide a radiation image conversion panel.

  More specifically, the object of the present invention was proposed by the present applicant in Japanese Patent Application No. 2002-236306 (see Japanese Patent Application Laid-Open No. 2004-77236) and Japanese Patent Application No. 2004-346832 related to the prior application, Further improved the manufacturing method (vacuum evaporation method) of the vapor-deposited phosphor layer so that the surface of the phosphor layer is suitably used without damaging the columnar crystal structure in the phosphor layer composed of the columnar crystals formed by these methods. An object of the present invention is to provide a method for producing a phosphor layer for a radiation image conversion panel including smoothing of a phosphor layer to be flattened, and a radiation image conversion panel having a phosphor layer produced by the method.

In order to achieve the above-described object, a method for producing a phosphor layer according to the present invention includes a film forming step of forming a phosphor layer made of columnar crystals on a substrate by a vapor deposition method, and the phosphor formed A method for producing a phosphor layer of a radiation image conversion panel having a polishing step for polishing the surface of the layer,
The polishing step is performed by relatively moving the polishing material and the substrate in a state where the polishing material is disposed at a predetermined interval between the polishing material and a predetermined reference surface. This is a step of polishing the surface by a predetermined thickness, and by performing this polishing step in a plurality of times, the flatness of the surface of the phosphor layer is set to a desired value.

Here, in the polishing step performed in a plurality of times, a plurality of unit polishing steps in which a plurality of types of predetermined polishing materials having different roughness are applied in a predetermined order are repeated a predetermined number of times for each unit polishing step. It is preferable.
Further, it is preferable that the unit polishing step is repeated by setting a predetermined polishing allowance.
Furthermore, the desired flatness value is preferably such that the surface waviness W _ca value is 10 μm or less and the surface roughness Ra value is 5 μm or less.
Furthermore, the predetermined polishing allowance is preferably 10 μm.

The radiation image conversion panel according to the present invention includes a phosphor layer manufactured by the above-described method for manufacturing a phosphor layer.
Further, the radiation image conversion panel according to the present invention includes a film forming process for forming a phosphor layer made of columnar crystals on a substrate by a vapor deposition method, and a polishing process for polishing the surface of the formed phosphor layer. A radiation image conversion panel using a phosphor layer formed by:
The surface waviness (filtered centerline waviness) W _{ca on} the surface of the phosphor layer has a value of 10 μm or less.
Here, the surface roughness Ra of the phosphor layer is preferably 5 μm or less.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, first, a phosphor film is formed on a predetermined substrate by a vacuum vapor deposition apparatus and an outline of a process for creating a phosphor sheet is described. The process of polishing the layer will be described in detail.

  An apparatus (vacuum deposition apparatus) for carrying out the method for producing a phosphor layer of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

  Here, first, as an example, the temperature is measured inside an evaporation container (crucible) serving as a resistance heating source by using a linear transport (details will be described later) type vacuum vapor deposition apparatus. Accordingly, a case where the crucible is heated, that is, the evaporation amount (= deposition rate) of the film forming material is controlled will be described.

FIG. 2 is a conceptual diagram of a phosphor sheet manufacturing apparatus that embodies the phosphor sheet manufacturing method that is the first step of the phosphor layer manufacturing method according to an embodiment of the present invention. 2A is a front view, and FIG. 2B is a side view.
A phosphor sheet manufacturing apparatus (hereinafter referred to as manufacturing apparatus) 10 shown in FIG. 2 includes a film forming material (evaporation source) to be a phosphor (matrix), and a film forming material to be an activator (activator). Is a device for producing a (storable) phosphor sheet by forming a layer made of a stimulable phosphor (hereinafter referred to as a phosphor layer) on the surface of the substrate S by binary vacuum vapor deposition that evaporates separately. .

Such a manufacturing apparatus 10 basically includes a vacuum chamber 12, a substrate holding / conveying mechanism 14, a heating evaporation unit 16, and a gas introduction nozzle 18.
In addition, it goes without saying that the manufacturing apparatus 10 may include various constituent elements of a known vacuum deposition apparatus such as a plasma generator (ion gun) as necessary. That is.

In the illustrated example, as a preferred example, cesium bromide (CsBr) as a phosphor component and europium bromide (EuBr _x (x is usually 2 to 3) as an activator component, Is preferably used as a film-forming material, and binary vacuum deposition is performed by resistance heating to form a phosphor layer made of CsBr: Eu, which is a storage phosphor, on the substrate S, and a phosphor sheet is formed. Make it. Therefore, an evaporation container (hereinafter referred to as a crucible) 50 serving as a resistance heating source for the phosphor and a crucible 52 serving as a resistance heating source for the activator are disposed in the heating evaporation unit 16.

  Here, in order to simplify the drawing and clarify the configuration, although not shown, a resistance heating power source for resistance heating is connected to each crucible 52. For the same reason, only one location is shown in FIG. 2A and illustration is omitted in FIG. 2B, but each crucible 50 is provided with a thermocouple 58, which will be described later, which is a temperature measuring means. Furthermore, the resistance heating power source 20 and the heating control means 22 are connected.

  In addition, the manufacturing apparatus 10 according to the present embodiment includes a gas introduction nozzle 18 that introduces an inert gas during film formation. Preferably, the vacuum chamber 12 is once evacuated to a high degree of vacuum and then evacuated. Introducing an inert gas such as argon from the gas introduction nozzle 18 while performing the vacuum degree of about 0.1 Pa to 10 Pa (particularly 0.5 to 3 Pa) in the vacuum chamber 12 (hereinafter referred to as medium vacuum), Under this vacuum, the phosphor layer is formed.

That is, the film-forming material (cesium bromide and europium bromide) is heated and evaporated by resistance heating in the heating evaporation unit 16, and the substrate S is conveyed linearly (hereinafter referred to as linear conveyance) by the substrate holding and conveying mechanism 14. Then, the phosphor layer is formed on the substrate S by vacuum deposition.
By forming the phosphor layer under a vacuum in which gas is introduced, the phosphor layer has a good columnar crystal structure, and a phosphor sheet having excellent image sharpness and stimulated emission characteristics is manufactured. can do.

A vacuum pump (not shown) is connected to the vacuum chamber 12.
The vacuum pump is not particularly limited, and various types of vacuum pumps that can be used as long as the required ultimate vacuum can be achieved can be used. As an example, an oil diffusion pump, a cryopump, a turbomolecular pump or the like may be used, and a cryocoil or the like may be used in combination as an auxiliary. In the manufacturing apparatus 10 for forming the phosphor layer described above, the ultimate vacuum in the vacuum chamber 12 is preferably 8.0 × 10 ⁻⁴ Pa or less.

The substrate holding and transporting mechanism 14 holds the substrate S and transports the substrate S along a linear transport path (hereinafter referred to as linear transport), and includes a substrate holding unit 30 and a transport unit 32. The
The conveying means 32 has a linear motor guide having a guide rail 34 and an engaging member 36 guided by the guide rail, a ball screw composed of a screw shaft 40 and a nut 42, a rotational drive source 44 of the screw shaft 40, etc. This is a known linear moving mechanism to be used.

  On the other hand, the substrate holding means 30 has an engagement member 48 that engages with the nut 42 of the ball screw and the engagement member 36 of the linear motor guide, and holds the substrate S at the lower end portion. And is linearly moved in a predetermined direction (the left-right direction in FIG. 2A and the direction perpendicular to the paper surface in FIG. 2B) by the conveying means 32.

  In the manufacturing apparatus 10 of the illustrated example, the substrate S is conveyed linearly in the predetermined direction by conveying the substrate holding means 30 by the conveying means 32 while the substrate S is held by the substrate holding means 30. In the illustrated example, the substrate S is transported in a straight line, and a plurality of evaporation sources are arranged in the transport orthogonal direction, thereby forming a phosphor layer with high film thickness distribution uniformity. .

  In general, as the film thickness is the same, the greater the number of passes through the upper portion of the heating evaporation unit 16, the higher the film thickness distribution uniformity. Therefore, the phosphor layer is reciprocated several times. Is preferably formed. In addition, the number of reciprocations may be appropriately determined according to the target film thickness of the phosphor layer, the target film thickness distribution uniformity, and the like. The conveyance speed may be appropriately determined according to the conveyance speed limit of the apparatus, the number of reciprocations, the target phosphor layer thickness, and the like.

A heating evaporation unit 16 is disposed below the vacuum chamber 12.
The heating evaporation unit 16 is a part that evaporates cesium bromide and europium bromide, which are film forming materials, by resistance heating. Although not shown for the same reason as above, a shutter that shields the vapor of the film forming material from the heating evaporation unit 16 (the crucible 50 and the crucible 52) is disposed on the heating evaporation unit 16.

  As described above, as a preferred embodiment, the manufacturing apparatus 10 performs binary vacuum deposition in which cesium bromide as a phosphor component and europium bromide as an activator component are independently heated and evaporated. Is. Accordingly, the heating evaporation unit 16 includes the crucible 50 for cesium bromide (for phosphor) and the crucible 52 for europium bromide (for activator).

  As shown in the schematic top view of FIG. 3, in the illustrated manufacturing apparatus 10, both the crucible 50 and the crucible 52 are provided in a direction orthogonal to the transport direction of the substrate S (hereinafter simply referred to as the transport direction). Are arranged. Note that the crucibles are insulated from each other due to separation, insertion of an insulating material, or the like.

  Further, both the crucible 50 and the crucible 52 have two rows of crucibles, and the rows of crucibles 50 are arranged so as to sandwich the two crucible 52 rows in the transport direction. Further, the crucibles 50 and crucibles 52 that are adjacent to each other in the transport direction are arranged so as to coincide with the arrangement direction of the rows to form a pair, and the crucibles 50 and the crucibles 52 of different rows are staggered in the arrangement direction. Arranged so as to fill the gaps in the same direction. This makes it possible to discharge steam uniformly in the arrangement direction.

  In the manufacturing apparatus 10 of the illustrated example, the entire surface of the substrate S is formed by linearly transporting the substrate S and arranging the resistance heating evaporation crucibles 50 and 52 in a direction perpendicular to the transport direction, as described above. Uniform exposure with the vapor of the film material enables formation of a phosphor layer with extremely high film thickness distribution uniformity.

  That is, the phosphor layer is formed by vacuum deposition while the substrate S is conveyed linearly, so that the moving speed on the surface of the substrate S (non-deposition surface) is made uniform over the entire surface, and a plurality of crucibles (resistance heating evaporation sources) ) Are arranged in a straight line in the direction perpendicular to the transport direction, and the vapor deposition of the film forming material can be uniformly exposed on the entire surface of the substrate S with an extremely simple evaporation source arrangement, and the film thickness distribution is uniform. A highly fluorescent layer can be formed. In particular, in the medium-vacuum vacuum deposition as described above, there is a collision between the gas particles such as argon and the evaporated film forming material, so that the distance between the substrate and the crucible is larger than that in the ordinary high-vacuum deposition. Therefore, since the film-forming material reaches the substrate S before diffusing into the system, the effect is great.

  In addition, by having such a configuration, the activator component can be dispersed highly uniformly in the stimulable phosphor layer in both the surface direction and the thickness direction of the phosphor layer. A phosphor sheet excellent in uniformity such as emission characteristics and sensitivity can be obtained.

  The crucibles 50 and 52 are made of a refractory metal such as tantalum (Ta), molybdenum (Mo), tungsten (W), and the like, and are energized from electrodes (not shown), like the crucible used for vacuum deposition by ordinary resistance heating. This is a crucible serving as a resistance heating source that generates heat by itself and heats / melts the filled film forming material to evaporate.

In the stimulable phosphor, the activator and the phosphor are, for example, about 0.0005 / 1 to 0.01 / 1 in molar concentration ratio, and most of the phosphor layer is the phosphor.
A crucible 52 for europium bromide (activator) with a small deposition amount is a lid having a slit-like steam outlet extending from the upper surface of a normal boat-type crucible in a direction coinciding with the arrangement direction of the crucible. It is obstructed by the body. In addition, a square cylindrical chimney (chimney) 52a having an upper and lower opening surface of the same shape is fixed to the vapor discharge port, and the vapor of the film forming material is discharged from the chimney 52a.

  As described above, although not shown, a resistance heating power source is connected to each crucible 52. Moreover, since an activator has little vapor deposition amount (evaporation amount), as an example, control of heating is performed by constant current control. Note that the heating control method of the crucible 52 is not limited to this, and various methods used in vacuum vapor deposition by resistance heating, such as a thyristor method, a DC method, and a thermocouple feedback method, can be used.

  On the other hand, the crucible 50 for cesium bromide (for phosphor) having a large deposition amount is a large drum-type (cylindrical) crucible. The crucible 50 has a slit-like steam outlet extending in the axial direction of the drum on the side surface of the drum. Further, a rectangular cylindrical chimney 50a having the same upper and lower opening surfaces is fixed to the vapor outlet, and similarly, the vapor of the film forming material is discharged from the chimney 50a. The crucible 50 is arranged so that the axis of the drum coincides with the arrangement direction of the crucible 50, that is, the slit-shaped chimney 50 a coincides with the arrangement direction of the crucible 50.

  By having such a chimney (chimney-like steam discharge part), when bumping occurs due to local heating or abnormal heating in the crucible, it is possible to prevent the film forming material from being unexpectedly ejected from the crucible. Contamination of the substrate S can be prevented. In particular, in the above-described medium vacuum deposition, it is necessary to bring the substrate S and the evaporation source close to each other as described above.

  Here, the crucible 50 for cesium bromide measures the temperature in the crucible, and controls the evaporation amount (that is, the deposition rate) of the film forming material from each crucible according to the result of the measurement. The vacuum vapor deposition method is performed.

  FIG. 4 shows a schematic diagram of the crucible 50. 4, (a) is a top view, (b) is a partially cutaway front view (viewed from the same direction as FIG. 2 (b)), and (c) is a side view (FIG. 2 (a)). The figure seen from the same direction.

  As described above, the crucible 50 is a drum-type crucible, and a slit-like steam discharge port 50b that coincides in the axial direction is formed on the side surface of the drum, and the steam discharge port 50 has a rectangular tube whose upper and lower surfaces are open. A shaped chimney 50a is fixed. In the chimney 50a, a substantially Z-shaped rib 50c is disposed in order to support from the inside and improve the strength.

  Further, a shielding member 62 for preventing the bumped film forming material from being ejected is fixed in the crucible 50. The shielding member 62 is formed by folding a long rectangular plate material in the short direction to form a substantially T shape, and the attachment portion 62a is formed by vertically folding both longitudinal ends of the upper portion of the T shape upward. When viewed from above, the shielding member 62 is disposed in the crucible 50 (drum) so as to close the steam outlet 50 on the T-shaped upper surface, and the attachment portion 62a is fixed to the drum end surface from the inside.

Electrodes 60 are fixed to both end faces of the crucible 50 (drum).
The electrode 60 is connected to a resistance heating power source 20 (hereinafter simply referred to as a power source 20). The power source 20 is not particularly limited, and various types of power sources that are used for heat generation of a crucible serving as a resistance heating source in vacuum deposition by resistance heating can be used.

  In the illustrated example, a thermocouple 58 serving as temperature measuring means is inserted into the chimney 50a of the crucible 50 through the side surface (end surface in the slit extending direction). In order to prevent a temperature measurement error caused by a weak voltage from the power supply 20, the thermocouple 58 (its thermal contact) is preferably arranged so as not to contact the crucible 50. In the illustrated example, the thermocouple 58 is inserted from the end face of the chimney 50a in the slit extending direction, but the present invention is not limited to this, and the thermocouple 58 is inserted from the end face of the chimney 50a in the short slit direction. It is also preferable to insert a pair 58.

  In the crucible 50, the film forming material is filled so that the melted film forming material (melted evaporation source) does not come into contact with the shielding member 62 in a normal use state. Accordingly, the thermocouple 58 disposed in the chimney 50a does not contact the melt evaporation source. In the embodiment in which temperature measurement is performed without contact with the melt evaporation source, in order to perform highly accurate temperature measurement, the thermal contact of the thermocouple 58 is directly in contact with the film forming material vapor. Is preferred.

The heating control means 22 is connected to the thermocouple 58.
Here, the heating control means 22 is configured so that the temperature at the temperature measurement position becomes a predetermined temperature according to the temperature measurement result by the thermocouple 58 (that is, the evaporation amount of the film forming material becomes a predetermined rate). The power supplied from the power source 20 to the crucible 50 is controlled.

When the vapor deposition operation is started, the evaporation state is determined by measuring the temperature in the evaporation container. This may be performed using, for example, a graph showing the relationship between the temperature in the evaporation container and the evaporation rate, or a comparison table created based on the graph, which has been obtained in advance.
And the heating control means 22 observes the progress of vapor deposition continuously, and performs heating control according to the temperature measurement result by the thermocouple 58 so that the evaporation rate becomes a predetermined value.

  As described above, since the activator has a very small amount of vapor deposition (evaporation amount), in the above embodiment, the control of the heating and evaporation in the crucible 52 for the activator is constant current control. The invention is not limited to this, and in the crucible 52 for the activator, the temperature may be measured in the crucible, and heating may be controlled according to the measurement result to control the deposition rate. Needless to say.

  Hereinafter, the operation of forming the phosphor layer on the substrate S (manufacturing the phosphor sheet) by the manufacturing apparatus 10 will be described.

  First, the vacuum chamber 12 is opened, the substrate S is held on the substrate holding means 30 of the substrate holding and transport mechanism 14, cesium bromide is contained in all the crucibles 50, and europium bromide is contained in all the crucibles 52. Then, the shutter is closed and the vacuum chamber 12 is further closed.

Next, the vacuum evacuation means is driven to evacuate the vacuum chamber 12. When the inside of the vacuum chamber reaches, for example, 8 × 10 ⁻⁴ Pa, the evacuation is continued and the gas introduction nozzle 18 enters the vacuum chamber 12. Argon gas is introduced, the pressure in the vacuum chamber 12 is adjusted to, for example, 1 Pa, and the resistance heating power source is driven to energize all the crucibles 50 and crucibles 52 to heat the film-forming material. After the elapse of time, the rotation drive source 44 is driven to start transporting the substrate S, the shutter is opened, and formation of the phosphor layer on the surface of the substrate S is started.

  During film formation, the temperature in the crucible 50 is measured by the thermocouple 58 in all the crucibles 50, and the heating control means 22 controls the power supplied from the power source 20 to the crucible 50 according to the result. The evaporation rate is controlled by controlling the evaporation amount of the film forming material from the crucible 50.

  When the reciprocation of the predetermined number of times of linear conveyance set according to the thickness of the phosphor layer to be formed is completed, the linear conveyance of the substrate S is stopped, the shutter is closed, the resistance heating power is turned off, and the gas The introduction of the argon gas by the introduction nozzle 18 is stopped, dry nitrogen gas or dry air is introduced, the inside of the vacuum chamber 12 is brought to atmospheric pressure, then the vacuum chamber is opened, and the substrate S on which the phosphor layer is formed, that is, The produced phosphor sheet is taken out.

  In addition, since this fluorescent substance sheet formed the fluorescent substance layer by controlling a vapor deposition rate according to the temperature measurement result in the inside of the crucible 50, it is a highly accurate film | membrane formed into a film with the appropriate vapor deposition rate High quality with thick fluorescence.

  Next, as another example of the method for manufacturing the phosphor layer, a case where a general rotary evaporation type vacuum evaporation apparatus is used will be described.

  Here, the phosphor material with a large deposition amount is evaporated by electron beam heating, and film formation is controlled more favorably, and resistance heating distributes a small amount of film forming material with high spatial uniformity. Since this can be used as a heating means for the activator material, a small amount of the activator material vapor is suitably dispersed in the mixed steam, and the activator is more uniformly dispersed. This makes it possible to form a high-quality phosphor layer.

FIG. 5 is a conceptual diagram of a phosphor sheet manufacturing apparatus that embodies a phosphor sheet manufacturing method that is the first stage of a phosphor layer manufacturing method according to another embodiment of the present invention.
The phosphor sheet manufacturing apparatus (hereinafter also simply referred to as manufacturing apparatus) 110 in the illustrated example is a vacuum deposition type manufacturing apparatus proposed by the present applicant in the aforementioned Japanese Patent Application Nos. 2002-4291 and 2002-19631. It is equivalent.

  The manufacturing apparatus according to the present embodiment forms a (storable) phosphor sheet by forming a stimulable phosphor layer on the surface of a sheet-like substrate (here, a glass substrate) S by binary vapor deposition. Basically, a so-called substrate rotation type vacuum vapor deposition apparatus configured to include a vacuum chamber 112, a substrate holding / rotation mechanism 114, and a heating evaporation unit 122 is used.

The vacuum chamber 112 is connected to a vacuum pump (evacuation means) (not shown) for exhausting the system to a predetermined degree of vacuum.
In the illustrated manufacturing apparatus 110, as an example, binary vacuum deposition using cesium bromide (CsBr) and europium bromide (EuBrx (x is usually 2 to 3)) as a film forming material is performed. Then, a phosphor layer having CsBr: Eu as a stimulable phosphor is formed on the glass substrate S.

Moreover, in the phosphor sheet produced by the production apparatus according to the present invention, the stimulable phosphor is not limited to the above CsBr: Eu, and various types can be used.
Preferably, a stimulable phosphor that exhibits stimulated emission in the wavelength range of 300 nm to 500 nm upon irradiation with excitation light having a wavelength in the range of 400 nm to 900 nm is used. Such photostimulable phosphors are described in detail in JP-B-7-84588, JP-A-2-193100, and JP-A-4-310900.

Returning to FIG. 5, the description will be continued. The vacuum chamber 112 is a known vacuum chamber (bell jar, vacuum chamber) that is formed of iron, stainless steel, aluminum, or the like and is used in a vacuum deposition apparatus.
In the illustrated example, in the vacuum chamber 112, a substrate holding / rotating mechanism 114 is disposed above, and a heating evaporation unit 122 is disposed below. In addition, although the case where only one set of the heating evaporation unit 122 is provided is illustrated here, it is needless to say that a plurality of sets of the heating evaporation unit 122 may be provided.

The substrate holding / rotating mechanism 114 holds and rotates the glass substrate S, and includes a rotation drive source (motor) 28 a and a turntable 130.
The turntable 130 is a disc composed of a main body 132 that holds the upper glass substrate S and a lower (heated evaporation section 122) sheath heater 134, and a rotary shaft 128 that engages with the motor 128a is fixed at the center thereof. Is done. The turntable 130 holds the glass substrate S on the lower surface (that is, the lower surface of the sheath heater 134) at a predetermined position corresponding to a heating evaporation unit 122 (evaporation position of the film forming material) described later, and is rotated at a predetermined speed by the rotating shaft 128. It is rotated by. The sheath heater 134 heats the glass substrate S to be formed from the back surface (the surface opposite to the film forming surface). The glass substrate S may be held on the turntable 130 (the lower surface of the sheath heater 134) with the film formation surface facing downward by a method using a known jig 114a or the like (see FIG. 5).

A set (two) of heating and evaporation units 122 are arranged below the substrate holding / rotating mechanism 114 in the vacuum chamber. FIG. 6 (formerly FIG. 3) shows a conceptual diagram of the heating evaporation unit 122. 6A shows a top view (viewed from above in FIG. 5), and FIG. 6B shows a front view (viewed in the same direction as FIG. 5).
As described above, the manufacturing apparatus 110 according to the present embodiment uses cesium bromide and europium bromide as film forming materials, and performs binary vacuum evaporation in which these are individually heated and evaporated. The heating evaporation unit 122 includes a europium evaporation unit (hereinafter referred to as Eu evaporation unit) 138, a cesium evaporation unit (hereinafter referred to as Cs evaporation unit) 140, and a material supply device 146.

The Eu evaporating unit 138 is a part that causes the resistance heating device 142 to evaporate the europium bromide (activator material) accommodated in the evaporation position Pe (crucible) by resistance heating. Here, there is no particular limitation on the resistance heating device 142 for heating and evaporating the activator material, and any vacuum evaporation device can be used as long as it can be suitably evaporated according to the activator material used. Various types used in the can be used.
Moreover, there is no restriction | limiting in particular also in the output at the time of performing resistance heating, What is necessary is just to set suitably according to activator material etc., but in the example of illustration (it changes with resistance values of a heater), about 50A-1000A do it.

On the other hand, the Cs evaporation unit 140 is an electron beam heating apparatus that heats and evaporates cesium bromide, which is a phosphor material, by irradiating the evaporation position Pc (Haas) with an electron beam (EB) emitted from the electron gun 144. is there.
In the formation of the phosphor layer by vacuum deposition, the manufacturing apparatus 110 according to the present embodiment uses binary deposition in which the phosphor material and the activator material are separately heated and evaporated, and the activator material is heated and evaporated. Fluorescence having an extremely high quality phosphor layer in which the activator is uniformly dispersed in the phosphor layer (that is, in the phosphor) by performing resistance heating and evaporating the phosphor material by electron beam heating. The body sheet can be manufactured efficiently.

In the manufacturing apparatus 110 according to the present embodiment, the Cs evaporation unit 140 can basically use various known evaporation means as long as the Cs evaporation unit 140 performs heating with an electron beam.
Therefore, the electron gun is not particularly limited, and is used in vacuum deposition, such as a 180 ° deflection gun that deflects an electron beam by 180 ° and enters the evaporation position, a 270 ° deflection gun, and a 90 ° deflection straight gun. Various electron guns are available. In the illustrated example, the electron gun 144 uses a 270 ° deflection gun as an example.

There is no limitation on the emission current of the electron gun 144 and the accelerating voltage of the EB as long as it is sufficient according to the film forming material and the film thickness to be formed.
In the illustrated example, as an example, the acceleration voltage of EB is preferably -1 KV to -30 KV, and the emission current is preferably 50 mA to 2 A by the Cs evaporation unit 140.

  Here, as described above, the phosphor layer formed on the substrate is much thicker than a normal vacuum vapor deposited film, and even if it is thin, it is about 200 μm, usually about 500 μm, and if thick, it exceeds 1000 μm. There is also. Further, the activator and the phosphor are, for example, about 0.0001 / 1 to 0.01 / 1 in molar concentration ratio, and most of the phosphor layer is the phosphor. Therefore, in the manufacturing apparatus 110 of the illustrated example, as a preferable aspect, the Cs evaporation unit 140 includes a material supply unit 146 that is a supply unit of cesium bromide.

In the illustrated example, the material supply means 146 basically includes a cylinder 148, a piston 150, a casing 152, and a lifting / lowering means (motor) 154.
The cylinder 148 is a cylinder fixed to the wall surface of the vacuum chamber 112 in a state where a part of the cylinder 148 penetrates the lower surface of the vacuum chamber 112 and protrudes outside so that the upper end portion thereof coincides with the electron beam irradiation position. . That is, in the illustrated example, the cylinder 148 is a so-called hearth, and its upper end is the evaporation position Pc of cesium bromide.

The piston 150 includes a columnar piston head 150a that is loosely fitted in the cylinder 148, and a piston pin 150b that fixes the piston head 150a to the tip. Lifting / lowering means 154 for moving the piston 150 up and down (in the direction of arrow c) is engaged with the piston pin 150b.
Further, the open end of the cylinder 148 is covered with a casing 152 so that the inside of the vacuum chamber 112 is kept airtight, and the piston pin 150b is axially sealed to the casing 152 so as to be reciprocated in the up and down direction by a bearing (not shown). Be supported.

Cesium bromide is molded into a cylindrical shape having a slightly smaller diameter than the inner diameter of the cylinder 148, and is accommodated in the cylinder 148 while being placed on the piston head 150a.
When cesium bromide at the evaporation position Pc is consumed by film formation on the substrate, the lifting / lowering means 154 operates accordingly to raise the columnar cesium bromide. Thus, cesium bromide is always supplied to the upper surface of the cylinder 148, that is, the evaporation position, and it is possible to suitably cope with the formation of a thick film exceeding 200 μm.

  As described above, the amount of activator contained in the phosphor layer is extremely small relative to the phosphor, and component control of the phosphor layer is important. According to the study by the present inventors, in order to form a high-quality phosphor layer having a thickness exceeding 200 μm in which an activator is uniformly dispersed and added (dope) in the phosphor, It is preferable that vapor is separately generated for the film forming material and the film forming material for the activator to generate a mixed vapor in which both are sufficiently mixed, and the mixed vapor is used to form a film on the substrate.

  In addition, here, by evaporating the phosphor material with a large amount of deposition by electron beam heating, the evaporation can be performed with good controllability and efficiency, and the film formation can be controlled more suitably. become. On the other hand, resistance heating can disperse and evaporate a very small amount of film-forming material with high spatial uniformity. Therefore, by using this as a heating means for the activator material, a small amount of deposition material is added to the mixed vapor. It is possible to form a high-quality phosphor layer in which the activator material vapor is suitably dispersed to more uniformly disperse the activator.

  Next, a polishing apparatus that polishes the phosphor layer formed on the substrate, which is the second stage of the phosphor sheet manufacturing method according to the present embodiment, will be described.

  FIG. 1 is a schematic side view for explaining a polishing process of a vapor-deposited phosphor layer according to this embodiment. Here, as an example, the surface of the phosphor layer 164a of a 430 mm square phosphor sheet 164 is fed out. A case where polishing is performed using a long polishing material (wrapping sheet) 162 having a width of 450 mm transferred by a winding drive mechanism is described as an example.

  That is, in the polishing process using the polishing apparatus 100 shown in FIG. 1, the surface of the phosphor sheet 164 locked on the sheet support 166 (actually, the surface of the phosphor layer 164 a on the phosphor sheet 64). The polishing is performed by moving the sheet support base 166 relative to the polishing unit 160 in the direction indicated by the arrow b in FIG. It is configured.

  Here, the above-described polishing unit 160 has a feeding portion 160a for sending a long polishing material 162, a winding portion 160b for winding the polishing material 162, and a polishing material 162 in a vertical direction with respect to the phosphor sheet 164 (FIG. 1 (a ) In a direction indicated by an arrow a) and a contact roller 160c to be contacted. Further, the sheet support base 166 is configured to reciprocate along the direction of arrow b in the figure by a moving mechanism in a horizontal plane (not shown).

  That is, the polishing unit 160 according to this embodiment has a predetermined clearance (P in the drawing) between the polishing material 162 and the reference surface of the phosphor sheet 164 (for example, the surface of the sheet support 166). The sheet support base 166 is reciprocated relative to the polishing material 162 and parallel to the reference surface by positioning in the vertical direction (indicated by an arrow a in FIG. 1A). (A direction indicated by an arrow b in FIG. 1B) is configured to perform polishing.

  In the following description, the surface on which the polishing material 162 actually polishes the phosphor layer 164a is referred to as the polishing surface with respect to the reference surface. This polishing surface is a surface parallel to the reference surface and in contact with the lowest point (contact roller) 160c of the polishing material 162.

  As the moving mechanism of the seat support 166 here, various known mechanisms such as a rack and pinion mechanism and a ball screw mechanism may be used to convert the rotation of a motor or the like as a drive source. The direction may be a movement in one direction, or a reciprocating movement that periodically switches the movement direction. In this case, the moving direction switching speed (frequency) may be appropriately determined.

  The relative movement speed (abrasion material contact speed) between the phosphor sheet 164 and the polishing material 162 may be determined as appropriate according to the characteristics of the phosphor layer and the characteristics of the polishing material. In the case of the phosphor layer (CsBr: Eu) shown in the form, since it is relatively soft, a considerable polishing rate can be obtained even at a low speed.

The value of the clearance P may be appropriately determined according to the characteristics of the polishing material 162 to be used, the characteristics of the phosphor layer 164a to be polished, and a desired cutting allowance.
Specifically, as shown in FIG. 1, the total value of the preferable thickness (average thickness) t of the phosphor layer and the thickness St of the substrate S, that is, P = t + St, and this value as the initial value is described above. Set between the reference plane.

Hereinafter, the phosphor layer deposition procedure in the manufacturing apparatus configured as described above and the polishing procedure in the polishing apparatus will be described.
As described above, the manufacturing apparatus 110 uses a rotary vacuum deposition apparatus. When manufacturing a phosphor panel, first, a film formation surface is formed on the lower surface of the turntable 130 of the substrate holding / rotating mechanism 114. After the glass substrate S is mounted facing downward, the vacuum chamber 112 is closed and decompressed, and the sheath heater 134 is driven to heat the glass substrate S from the back surface.

  When the inside of the vacuum chamber 112 reaches a predetermined degree of vacuum, the motor 128a rotates the turntable 130 at a predetermined speed, and the heating evaporation unit 122 drives the resistance heating device 142 of the Eu evaporation unit 138 to evaporate the position Pe. The europium bromide contained in the (crucible) is evaporated, and the electron gun 144 of the Cs evaporation unit 140 is driven to evaporate cesium bromide at the evaporation position Pc. The film formation of the phosphor layer is started.

Here, as described above, both evaporation positions are arranged close to each other, and the evaporation of europium bromide is performed by resistance heating. Therefore, in the heating evaporation unit 122, a very small amount of vapor of europium bromide is uniformly distributed. A mixed vapor of both film forming materials is formed, and CsBr: Eu in which the activator is uniformly dispersed is deposited by the mixed vapor.
When the phosphor film having a predetermined thickness is formed, the rotation of the turntable 130 is stopped, the vacuum chamber 112 is opened, and the glass substrate S on which the phosphor layer has been formed is taken out. In the case where film formation is performed continuously, the film formation may be performed by loading a new glass substrate S in the same manner as above.

The glass substrate S on which the phosphor layer is formed in the above process, that is, the phosphor sheet 164 is subjected to a polishing process by the polishing apparatus 100 after a predetermined time has elapsed.
The phosphor sheet 164 in this embodiment is set by, for example, locking the phosphor sheet 164 to the sheet support base 166 with a known locking member.

Here, the phosphor layer polishing method in the present invention has a desired thickness and surface undulation by repeating a polishing step of polishing the phosphor layer 164a by a predetermined amount of cutting allowance (polishing allowance) multiple times. A phosphor sheet having values of W _ca and surface roughness Ra within a predetermined range is manufactured.
At this time, the phosphor sheet is obtained by sequentially replacing and using a polishing material (a predetermined count wrapping sheet) having a predetermined roughness (grain size).

In the polishing step, the above-described polishing surface is set with a predetermined distance from the uppermost part (in most cases, the upper surface) of the phosphor layer 164a to the reference surface, and a predetermined number of polishing times (at least polishing dust This is a step of polishing the phosphor layer 164a by setting a predetermined cutting allowance, and polishing the same number of times when polishing until no more occurs.
Note that the number of times of polishing is that the sheet support 166 moves one way in the direction indicated by the arrow b in FIG. 1B and polishes the phosphor layer 164a of the phosphor sheet 164 once. To.

  Hereinafter, the polishing method of the present invention will be described more specifically.

As described above, the phosphor sheet 164 is locked to the panel support 166 by a locking member (not shown), and then the polishing unit 160 is moved in the vertical direction (indicated by the arrow a in FIG. 1A). Set the polishing surface and fix the positioning.
By the way, when the polishing surface is set for the phosphor layer that has not been subjected to the polishing process at all, the position of the polishing material 162 is such that the polishing material 162 is slightly in contact with the surface of the phosphor layer 164a (FIG. 1). The direction of the arrow (a) in (a) is fixed, the phosphor layer 164a is slightly polished to perform chamfering, and a polished surface is set with a predetermined cutting allowance for the surface.

When the positioning of the polishing unit 160 is completed, first, the feeding of the polishing material 162 in the polishing unit 160 is started. Further, the driving of a moving mechanism (not shown) provided in the support body 166 is started, and the sheet support base 166 is moved from the state of FIG. Polishing of the surface of the phosphor layer 164a of 164 is started.
The support 66 reciprocates in the direction indicated by the arrow b in FIG. 1B to polish the surface of the phosphor layer 64a.

  When the polishing is performed until no polishing dust is generated, the sheet support is performed until the polishing material contact portion (contact roller) 160c of the polishing unit 160 is retracted from above the phosphor sheet 164 as shown in FIG. The table 166 moves.

  In the polishing step described above, the phosphor layer surface can be polished with a desired cutting allowance. The phosphor layer is polished by repeating this polishing step a plurality of times. Here, as the number of polishing steps is increased, the polishing material (wrapping tape) is changed to one having a finer particle size (having a larger count), so that the phosphor layer without damaging the columnar structure constituting the phosphor layer 164a. Polishing can be performed to improve the flatness of the surface of 164a.

Thereby, a phosphor sheet having a predetermined thickness and including a phosphor layer having predetermined surface waviness and surface roughness values can be manufactured.
Note that the roughness of the lapping sheet used for surface polishing, the number of times of polishing, and the moving speed of the sheet support 66 may be determined by experimental measurement in advance.

〔Example〕
For example, the specific steps of polishing can be performed using Table 1 shown below.
Here, Table 1 shows the count of the lapping tape of the used polishing material, the cutting allowance, and the data of the number of polishing in each time of the polishing process repeated a plurality of times. The value of the count of the tape is specified in R 6001 of Japanese Industrial Standard (JIS).

  In this example, as shown in Table 1, first, lapping tape of # 600 was selected, and polishing was performed with a cutting allowance of 14 μm (one unit polishing step). Since polishing debris was not generated after 100 times of polishing, the polishing was further performed with a cutting allowance of 10 μm. Then, since polishing debris was not generated after 150 times of polishing, another 10 μm cutting allowance was set and polishing was performed in the same manner. Using the # 600 wrapping tape, the above polishing process was repeated 6 times for a total polishing of 64 μm.

  Next, the lapping tape was changed to # 1000 and the cutting allowance was set to 10 μm for polishing. When polishing was performed 200 times per unit polishing process, polishing scraps were not generated. Here, the polishing process using the # 1000 wrapping tape was repeated three times, for a total polishing of 30 μm.

  Similarly, the lapping tape was sequentially changed to # 3000 and # 6000, and each one step (one unit polishing step) was polished. As described above, the surface of the phosphor layer 164a was polished, and a total of 114 μm was polished.

The phosphor layer 164a of the phosphor sheet 164 thus produced has a surface waviness Wca value of 9.3 μmWca (fh 0.08 mm, fl8 mm) and a surface roughness Ra value of 2.3 μm Ra (λc 0.08 mm). )Met. However, the above-mentioned surface waviness Wca and surface roughness Ra are based on the provisions of Japanese Industrial Standard JIS B 0601; 1994.
Note that the number of repeated use of the wrapping sheet may be determined experimentally to some extent.

  According to the above embodiment, the phosphor layer on the phosphor sheet prepared by vapor deposition is finished to a predetermined thickness (uniform thickness), and from the surface, the protrusions generated during film formation are formed. This brings about a remarkable effect that a phosphor sheet having a phosphor layer with a good surface state can be obtained by removing foreign substances and the like.

  Moreover, according to the said embodiment and an Example, when there exists thickness nonuniformity or a wave | undulation etc. in the base substrate, it can be absorbed and the phosphor sheet excellent in the surface flatness can be obtained. It also has the effect of.

  The above embodiments and examples are only examples of the present invention, and the present invention should not be limited thereto, and appropriate modifications or changes may be made without departing from the scope of the present invention. Needless to say, improvements may be made.

  For example, in the above-described embodiment, a polishing apparatus using a long wrapping sheet (wrapping tape) is taken as an example. However, in addition to this, rotation is performed in a plane parallel to the phosphor layer surface of the phosphor sheet. A method using a polishing sheet (or grindstone) to be used, a method of reciprocating a flat wrapping sheet (so-called wrapping plate), and the like can be used.

  As described above in detail, according to the present invention, it is possible to realize a uniform thickness in a phosphor layer having a thickness of about 500 μm, or about 1000 μm when it is thick, and excellent optical characteristics based thereon. The phosphor layer has a remarkable effect of realizing the manufacturing method of the phosphor layer.

  More specifically, by polishing the surface of the phosphor layer of the phosphor sheet after film formation by the method as described above, the thickness non-uniformity is eliminated, and foreign matter generated during film formation is eliminated. It is possible to efficiently produce a phosphor sheet having a very high quality phosphor layer with stable optical characteristics, realizing a good surface state by removing the protrusions and the like caused by it It is.

(A), (b) is explanatory drawing of the grinding | polishing process of the fluorescent substance layer which is the 2nd step of the manufacturing method of the fluorescent substance layer which concerns on one Embodiment of this invention. (A) is a schematic front view of an example of the fluorescent sheet manufacturing apparatus which actualized the fluorescent sheet manufacturing method which is the 1st step of the manufacturing method of the fluorescent substance layer which concerns on one Embodiment, (b) is the schematic. It is a side view. It is a schematic plan view of the heating evaporation part of the fluorescent substance sheet manufacturing apparatus shown in FIG. (A) is a top view of the crucible of the phosphor sheet manufacturing apparatus shown in FIG. 2, (b) is the same schematic front view, and (c) is a schematic side view of the same. It is a conceptual diagram which shows the other example of the phosphor sheet manufacturing apparatus which actualized the manufacturing method of the phosphor sheet which is the 1st step of the manufacturing method of the phosphor layer which concerns on one Embodiment. It is a conceptual diagram of the heating evaporation part which concerns on embodiment. It is explanatory drawing of the information reading from a fluorescent substance sheet.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 (Phosphor sheet) Manufacturing apparatus 12 Vacuum chamber 14 Substrate holding conveyance means 16 Heating evaporation part 18 Gas introduction nozzle 20 (Resistance heating) Power supply 22 Heating control means 30 Substrate holding means 32 Substrate conveyance means 34 Guide rails 36, 48 Engagement Member 40 Screw shaft 42 Nut portion 44 Rotation drive source 50, 52 Crucible 58 Thermocouple 62 Shield member 100 Polishing device 114 Substrate holding / rotation mechanism 122 Heating evaporation portion 130 Turntable 132 Turntable body 134 Sheath heater 138 Eu evaporation portion 140 Cs evaporation Part 142 Resistance heating device 144 Electron gun 146 Material supply device 160 Polishing unit 160a (Polishing material) Sending unit 160b (Polishing material) Winding unit 160c Contact roller 162 Polishing material 164 Phosphor sheet 164a Phosphor layer 166 Over door supporting base S glass substrate

Claims (8)

A film forming step of forming a phosphor layer made of columnar crystals on a substrate by vapor deposition;
A method for producing a phosphor layer of a radiation image conversion panel having a polishing step for polishing the surface of the formed phosphor layer,
The polishing step includes
The surface of the phosphor layer has a predetermined thickness by relatively moving the polishing material and the substrate in a state where the polishing material is disposed at a predetermined interval between the polishing material and a predetermined reference surface. Only polishing, and
A method for producing a phosphor layer, characterized in that the flatness on the surface of the phosphor layer is set to a desired value by performing this polishing step in a plurality of times. The polishing step performed in a plurality of times,
2. The phosphor layer according to claim 1, wherein a plurality of unit polishing steps in which a plurality of types of predetermined polishing materials having different roughness are applied in a predetermined order are repeated a predetermined number of times for each unit polishing step. Method. The unit polishing step includes
The method for producing a phosphor layer according to claim 2, wherein each is repeated by setting a predetermined polishing allowance. The method for producing a phosphor layer according to any one of claims 1 to 3, wherein the desired flatness value is a surface waviness _Wca value of 10 µm or less and a surface roughness Ra value of 5 µm or less.   The method for manufacturing a phosphor layer according to claim 3 or 4, wherein the predetermined polishing allowance is 10 m.   The radiation image conversion panel which has the fluorescent substance layer manufactured using the manufacturing method of the fluorescent substance layer in any one of Claims 1-5. A film forming step of forming a phosphor layer made of columnar crystals on a substrate by vapor deposition;
A radiation image conversion panel using a phosphor layer formed by a polishing step for polishing the surface of the formed phosphor layer,
A radiation image conversion panel, wherein the surface waviness (filtered center line waviness) W _ca of the phosphor layer is 10 μm or less.   The radiation image conversion panel according to claim 7, wherein the phosphor layer has a surface roughness Ra of 5 μm or less.

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