JP3564628B2 - X-ray sensor and X-ray inspection device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an X-ray sensor and an X-ray inspection apparatus used in a factory or the like, and more particularly, to a high-resolution sensor for realizing high-precision inspection at low cost.
[0002]
[Prior art]
FIG. 25 is a block diagram showing a basic configuration of a conventional X-ray sensor. In FIG. 25, reference numeral 13 denotes a fluorescence conversion unit, which usually has a structure in which a phosphor substance is usually applied on glass. Reference numeral 2 denotes a photoelectric conversion unit, for example, a CCD sensor. In the configuration shown in FIG. 25, the X-rays are converted into light in the fluorescence conversion unit 13 and the light is converted into an image in the photoelectric conversion unit 2 to output an image signal. An amplifier is often installed between the fluorescence conversion unit 13 and the photoelectric conversion unit 2 in order to increase the sensor sensitivity.
[0003]
In addition, in order to realize high sensitivity and high resolution in the sensor, the fluorescent material of the fluorescent conversion unit 13 having a fiber structure is often used. FIG. 26 is a diagram for explaining a phosphor having a fiber-like structure. FIG. 26A is a cross-sectional view of a phosphor containing cesium iodide (CsI: Tl) as a main component, and FIG. 26B schematically shows a state in which fluorescence proceeds in a fiber F of the phosphor. It is a thing.
[0004]
In the fluorescence conversion unit 13, the X-rays generate light when the X-rays hit the phosphor. To increase the sensitivity, it is advantageous to use a thick phosphor, but the image is blurred due to light diffusion inside the phosphor, which is disadvantageous for high resolution. Therefore, in the case of the fiber structure as shown in FIG. 26, since the fluorescent light hardly comes out of the fiber F, the fluorescent material can be made thicker with less light diffusion.
[0005]
[Problems to be solved by the invention]
As described above, the resolution of the fluorescence conversion unit 13 corresponds to the resolution of the sensor, but there is a limit to the fineness or variation in the size of the fiber crystal as shown in FIG. The resolution is about 25 μm.
[0006]
Conventionally, when a resolution of 25 μm or less is required, an inspection is performed by enlarging an image using a microfocus X-ray tube. FIG. 27 is a diagram illustrating the concept of image magnification imaging using X-rays and blurring of an image caused by the focal size of the X-ray tube. As shown in FIG. 27, X-rays are emitted radially from the X-ray tube focal point. Since the X-ray has a very strong straightness, if the length of L2 (the distance from the inspection object to the X-ray sensor) shown in FIG. 27 is larger than L1 (the distance from the focal point of the X-ray tube to the inspection object), The image on the X-ray sensor is larger than the object to be inspected and becomes an enlarged image.
[0007]
At this time, a problem is an image blur due to the focal size of the X-ray tube. FIG. 27A shows an image taken with an X-ray tube having a large focal size, and FIG. 27B shows an image taken with an X-ray tube having a small focal size. The X-rays passing through the same point on the inspection target are added by X-rays from all the points for the focal size, so that on the X-ray sensor, Δu1 in FIG. 27A and Δu2 in FIG. 27B. And the image is blurred by that size. Therefore, when enlarging an image, a microfocus X-ray tube having a small focus as shown in FIG. 27B is used to prevent the blur from becoming large. At present, the focus size of the microfocus X-ray tube is practically about 1 μm, and inspection can be performed with that level of resolution.
[0008]
Further, if L2 approaches zero as much as possible, the image blurs Δu1 and Δu2 also become substantially zero, and it is possible to carry out a precise inspection without having to care much about the focus size. However, in this state, the size of the inspection object is substantially the same as the size of the image on the X-ray sensor, and the resolution of the fluorescence conversion unit 13 of the sensor = image resolution.
[0009]
As described above, in a precision inspection requiring a screen resolution of 10 μm or less, it is necessary to use a microfocus X-ray tube. However, the microfocus X-ray tube is currently very expensive at 5 to 20 million yen, and is not at a price level that can be easily used for inspection in factories and the like. Therefore, if the resolution of the sensor is increased and an X-ray tube with a cost level of 500,000 to 2,000,000 yen can be used for precision inspection, the cost of the precision X-ray inspection machine will be drastically reduced, and the precision of electronic components will be reduced. It is thought that the spread to the joint inspection field etc. will be promoted.
[0010]
Therefore, an object of the present invention is to provide a high-resolution X-ray sensor by forming the shape of a phosphor substance with high accuracy.
[0012]
Another object of the present invention is to provide an X-ray sensor with high sensitivity and high resolution by forming various phosphor materials with high accuracy.
[0016]
Another object of the present invention is to provide a high-resolution X-ray sensor by structuring a pattern of forming a fluorescent substance using a thin film that is difficult to transmit X-rays and a thin film that easily transmits X-rays.
[0017]
It is another object of the present invention to provide a high-resolution X-ray sensor by improving the controllability of the formation of a phosphor substance on a substrate by the surface roughness of the substrate.
[0023]
Another object of the present invention is to provide an X-ray sensor with high image quality and high resolution.
[0024]
Another object of the present invention is to provide a high-quality and high-resolution X-ray sensor according to the purpose.
[0025]
Another object of the present invention is to provide a high-resolution and high-resolution image.Each of the aboveAn object of the present invention is to provide a highly accurate X-ray inspection device by using an X-ray sensor.
[0026]
[Means for Solving the Problems]
In order to solve the above problems, the present inventionIsAn X-ray sensor comprising: a fluorescent conversion unit that converts X-rays into light; and a photoelectric conversion unit that converts light generated by the fluorescent conversion unit into an image signal.A film having a property of not easily transmitting X-rays and a film having a property of easily transmitting X-rays are provided in parallel in a direction perpendicular to the X-ray incident direction on the substrate surface, Phosphor layer in the direction perpendicular toCharacterized byUse X-ray sensor.
[0027]
Also, XAn X-ray sensor comprising: a fluorescence conversion unit that converts a line into light; and a photoelectric conversion unit that converts light generated by the fluorescence conversion unit into an image signal, wherein the fluorescence conversion unitThe surface of any part of the substrate is processed to be rougher than other parts,FormingAndFeatureX-ray sensor may be used.
[0028]
Also,In an X-ray inspection apparatus that performs an X-ray inspection on an inspection object using an X-ray sensor, the X-ray sensor has a structure in which a fluorescent substance is formed on a substrate and converts X-rays into light. And a photoelectric conversion means for converting light generated from the fluorescence conversion means into an image signal, and as the fluorescence conversion means, a film having a property of hardly transmitting X-rays on the substrate surface and an X-ray. An X-ray sensor equipped with a film having a property of easily transmitting is provided in parallel in the direction perpendicular to the X-ray incident direction, and a phosphor layer is provided in contact with the film in a direction perpendicular to the X-ray incident direction.Characterized byX-ray inspection equipment can be used.
[0029]
Also,In an X-ray inspection apparatus that performs an X-ray inspection on an inspection object using an X-ray sensor, the X-ray sensor has a structure in which a fluorescent substance is formed on a substrate and converts X-rays into light. And a photoelectric conversion means for converting light generated from the fluorescence conversion means into an image signal, and as the fluorescence conversion means, an arbitrary portion of the substrate has a rougher surface than other portions. Equipped with an X-ray sensor that has been processed and forms a phosphor substance on its substrateCharacterized byX-ray inspection equipment can be used.
[0033]
BEST MODE FOR CARRYING OUT THE INVENTION
The invention described in claim 1 of the present invention, XAn X-ray sensor comprising: a fluorescence conversion unit for converting a line into light; and a photoelectric conversion unit for converting light generated from the fluorescence conversion unit into an image signal, wherein the fluorescence conversion unitA film having a property of not easily transmitting X-rays and a film having a property of easily transmitting X-rays are provided in parallel in a direction perpendicular to the X-ray incident direction on the substrate surface, Characterized in that a phosphor layer is provided in a direction perpendicular to theA high-resolution sensor can be provided.
[0034]
Of the present inventionThe invention described in claim 2 isAn X-ray sensor comprising: a fluorescence conversion unit that converts X-rays into light; and a photoelectric conversion unit that converts light generated by the fluorescence conversion unit into an image signal. The part is processed to have a rougher surface roughness than other parts, and the phosphor material is formed on the substrate.A high-resolution sensor can be provided.
[0035]
Of the present inventionThe invention according to claim 3 is:In an X-ray inspection apparatus that performs an X-ray inspection on an inspection object using an X-ray sensor, the X-ray sensor has a structure in which a fluorescent substance is formed on a substrate and converts X-rays into light. And a photoelectric conversion means for converting light generated from the fluorescence conversion means into an image signal, and as the fluorescence conversion means, a film having a property of hardly transmitting X-rays on the substrate surface and an X-ray. An X-ray sensor having a film that easily transmits light was provided in parallel in the direction perpendicular to the X-ray incident direction, and a phosphor layer was provided in contact with the film and provided in a direction perpendicular to the X-ray incident direction. X-ray inspection apparatus characterized by the following:Can be provided.
[0036]
Of the present inventionThe invention described in claim 4 isIn an X-ray inspection apparatus that performs an X-ray inspection on an inspection object using an X-ray sensor, the X-ray sensor has a structure in which a fluorescent substance is formed on a substrate and converts X-rays into light. And a photoelectric conversion unit that converts light generated from the fluorescence conversion unit into an image signal, and as the fluorescence conversion unit, an arbitrary portion of the substrate has a surface roughness greater than other portions. An X-ray inspection apparatus characterized by mounting an X-ray sensor which is processed and forms a phosphor substance on its substrate.Can be provided.
[0050]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0051]
FIG. 1 is a block diagram showing a configuration of an X-ray sensor according to a first embodiment of the present invention. Reference numeral 1 denotes a substrate on which a pattern is etched. Reference numeral 2 denotes a photoelectric conversion unit, for example, a CCD sensor. Reference numeral 3 denotes a plurality of phosphors provided on the substrate 1 for converting X-rays into light. The phosphors 3 are cesium iodide (CsI: Tl) or gadolinium processed products (Gd₂O₂S: Tb).
[0052]
The operation of the X-ray sensor shown in FIG. 1 will be described. First, the X-rays are converted into light by the phosphor 3 provided on the substrate 1. The converted light is extracted by the photoelectric conversion unit 2 as an image signal. Here, the phosphor 3 is formed and structured on the etched substrate 1.
[0053]
FIG. 2 shows a configuration example according to the structured pattern. As shown in FIG. 2, a phosphor 3 is thinly formed on a substrate 1 on which a simple uneven pattern is formed. Then, when the X-rays are applied to the phosphor 3, the generated fluorescence tends to diffuse in all directions, as shown in part A. However, if the light transmittance of the side surface of the substrate 1 is low, lateral diffusion is prevented, and an image with high resolution can be obtained.
[0054]
As described above, since the formation pattern of the phosphor 3 as the fluorescence conversion means is generated by etching the substrate 1 itself, the shape of the phosphor 3 can be formed with high accuracy, and the diffusion of the fluorescence can be prevented. The structure can be reduced, and a high-resolution sensor can be provided.
[0055]
FIG. 3 is a block diagram showing the configuration of the X-ray sensor according to the second embodiment of the present invention. In FIG. 3, reference numeral 4 denotes a thin film formed on the substrate 1 and provided with the phosphor 3 on the upper surface. The same members as those described in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.
[0056]
The operation of the X-ray sensor shown in FIG. 3 will be described. First, the X-rays are converted into light by the phosphor 3 formed on the substrate 1. The converted light is extracted by the photoelectric conversion unit 2 as an image signal. Here, the phosphor 3 is patterned and structured by forming a thin film 4 other than the phosphor 3 on the substrate 1.
[0057]
FIG. 4 shows a configuration example according to the structured pattern. As shown in FIG. 4, a simple concavo-convex pattern of a thin film 4 is formed on a substrate 1, and a thin phosphor 3 is formed thereon. When the X-rays are applied to the phosphor 3, the generated fluorescence tends to diffuse in all directions as shown in part A. However, if the light transmittance of the thin film 4 is low, lateral diffusion is prevented, and an image with high resolution can be obtained.
[0058]
As described above, since the formation pattern of the phosphor 3 as the fluorescence conversion means is generated by the thin film 4 other than the phosphor 3, the shape of the phosphor 3 can be formed with high accuracy, and the diffusion of the fluorescence can be prevented. It is possible to make the structure to reduce the number. Further, by selecting the type of the thin film 4 other than the phosphor 3, the controllability of the formation of the phosphor 3 on the substrate 1 can be enhanced, and a high-resolution sensor can be provided.
[0059]
FIG. 5 is a view showing a state in which a phosphor or a thin film is formed by sputtering for explaining the third embodiment of the present invention. In FIG. 5, reference numeral 5 denotes a phosphor or thin film target formed on the substrate 1, 6 denotes high energy particles, and 7 denotes target particles. The structure of the X-ray sensor according to the third embodiment is the same as the structure of the X-ray sensors according to the first and second embodiments, and a description thereof will be omitted. The same members as those described with reference to FIGS. 1 and 3 are denoted by the same reference numerals, and description thereof will be omitted.
[0060]
The sputtering operation shown in FIG. 5 will be described. First, a target 5 made of a phosphor or a thin film material to be formed on the substrate 1 and the substrate 1 are prepared. Next, high-energy particles 6 are generated and collided with the target 5 using a sputtering apparatus. As a result, target particles 7 are generated from the target 5 by the sputter evaporation action, and a film composed of the target particles 7 is formed on the substrate 1.
[0061]
As described above, the use of sputtering makes it possible to form a film of a substance having a high melting point, which is difficult to form by vacuum evaporation. Therefore, various phosphor substances can be formed with high accuracy, and a sensor with high sensitivity and high resolution can be provided.
[0062]
FIG. 6 is a block diagram showing the configuration of the X-ray sensor according to the fourth embodiment of the present invention. In FIG. 6, reference numeral 8 denotes a pixel provided in the photoelectric conversion unit 2. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0063]
The operation of the X-ray sensor shown in FIG. 6 will be described. First, the X-rays are converted into light by the phosphor 3 formed on the substrate 1. The converted light is received by the pixel 8 of the photoelectric conversion unit 2 and extracted as an image signal. Here, the phosphor 3 is structured by a pattern formed on the etched substrate 1 or the thin film, and is aligned with the pixel 8.
[0064]
As described above, a high-resolution sensor having a pixel-by-pixel resolution is provided by forming the shape of the phosphors 3 with high accuracy and associating each phosphor 3 with the position of the pixel 8 of the photoelectric conversion unit 2. can do.
[0065]
FIG. 7 is a block diagram showing the configuration of the X-ray sensor according to the fifth embodiment of the present invention. 7, reference numeral 9 denotes an X-ray shielding thin film provided on the substrate 1 and provided with the phosphor 3 on the upper surface. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0066]
The operation of the X-ray sensor shown in FIG. 7 will be described. First, the X-rays are converted into light by the phosphor 3 formed on the substrate 1. The converted light is extracted by the photoelectric conversion unit 2 as an image signal. Here, the phosphor 3 is structured by forming a pattern by forming an X-ray shielding thin film 9 on the substrate 1.
[0067]
FIG. 8 shows a configuration example of a structured pattern. As shown in FIG. 8, a simple concavo-convex pattern of the X-ray shielding thin film 9 is formed on the substrate 1, and the phosphor 3 is thinly formed thereon. When the X-rays are applied to the phosphor 3, the generated fluorescence tends to diffuse in all directions as shown in part A. However, if the light transmittance of the X-ray shielding thin film 9 is low, lateral diffusion is prevented, and an image with high resolution can be obtained. Further, since X-rays are absorbed in the portion where the X-ray shielding thin film 9 is present, the amount of X-rays reaching the phosphor 3 is small, and the fluorescence is weakened. Therefore, if the portion where the X-ray shielding thin film 9 is present is made thicker and narrower, and the portion where the X-ray shielding thin film 9 is not present is made wider, the fluorescent light is separated from the portion where the X-ray shielding thin film 9 is present. Can be reduced.
[0068]
As described above, since the formation pattern of the phosphor 3 as the fluorescence conversion means is formed by the thin film of the phosphor 3, the shape of the phosphor 3 can be formed with high precision and the diffusion of the fluorescence is reduced. Structuring is possible. Furthermore, structuring using the property of the thin film 9 that is difficult to transmit X-rays is possible, and a high-resolution sensor can be provided.
[0069]
FIG. 9 is a block diagram showing the configuration of the X-ray sensor according to the sixth embodiment of the present invention. In FIG. 9, reference numeral 10 denotes an X-ray transmitting thin film provided between the substrate 1 and the phosphor 3. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0070]
The operation of the X-ray sensor shown in FIG. 9 will be described. First, the X-rays are converted into light by the phosphor 3 formed on the substrate 1. The converted light is extracted by the photoelectric conversion unit 2 as an image signal. Here, the phosphor 3 is patterned and structured by forming an X-ray transparent thin film 10 on a substrate.
[0071]
FIG. 10 shows a configuration example of a structured pattern. As shown in FIG. 10, a simple concavo-convex pattern of the X-ray transmitting thin film 10 is formed on a substrate 1, and a thin phosphor 3 is formed thereon. When the X-rays are applied to the phosphor 3, the generated fluorescence tends to diffuse in all directions as shown in part A. However, if the light transmittance of the X-ray transmitting thin film 10 is low, the diffusion to the side is prevented, and an image with high resolution can be obtained. Furthermore, since the X-ray transmitting thin film 10 absorbs less X-rays, the amount of fluorescence in the concave pattern portion and the convex pattern portion is almost the same. Furthermore, the X-ray transmitting thin film 10 has a small absorption of X-rays and a small generation of scattered X-rays. Therefore, there is little fluorescence noise due to scattered X-rays.
[0072]
As described above, since the formation pattern of the phosphor 3 as the fluorescence conversion means is generated by a thin film other than the phosphor 3, the shape of the phosphor 3 can be formed with high precision and the diffusion of the fluorescence is reduced. Structuring is possible. Further, structuring and high image quality utilizing the property of the thin film 10 that easily transmits X-rays can be achieved.
[0073]
FIG. 11 is a block diagram showing the configuration of the X-ray sensor according to the seventh embodiment of the present invention. In FIG. 11, an X-ray shielding thin film 9 and an X-ray transmitting thin film 10 are provided in parallel between a substrate 1 and a phosphor 3. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0074]
The operation of the X-ray sensor shown in FIG. 11 will be described. First, the X-rays are converted into light by the phosphor 3 formed on the substrate 1. The converted light is extracted by the photoelectric conversion unit 2 as an image signal. Here, the phosphor 3 is patterned and structured by forming an X-ray shielding thin film 9 and an X-ray transmitting thin film 10 on a substrate.
[0075]
FIG. 12 shows a configuration example of a structured pattern. As shown in FIG. 12, a pattern of an X-ray shielding thin film 9 and an X-ray transmitting thin film 10 is formed on a substrate 1, and a thin phosphor 3 is formed thereon. This pattern is formed by, for example, etching after forming the X-ray shielding thin film 9 and then forming and etching the X-ray transmitting thin film 10. When the X-rays are applied to the phosphor 3, the generated fluorescent light tends to diffuse in all directions as indicated by a part B. However, if the light transmittance of the X-ray shielding thin film 9 and the X-ray transmitting thin film 10 is low, lateral diffusion is prevented, and an image with high resolution can be obtained. Furthermore, since the X-rays are absorbed in the portion where the X-ray shielding thin film 9 is present, the X-rays that reach the phosphor 3 are small and the fluorescence is weak. Therefore, if the portion where the X-ray shielding thin film 9 is present is made thicker and narrower and the portion where the X-ray shielding thin film 9 is not present is made wider, the fluorescence of the portion where the X-ray shielding thin film 9 is present becomes a boundary. Spread can be reduced. Further, since the structure is complicated by the X-ray transmission thin film 10, the effect of preventing the diffusion of the fluorescence is enhanced.
[0076]
As described above, since the formation pattern of the phosphor 3 as the fluorescence conversion means is characterized by being generated by a thin film other than the phosphor 3, the shape of the phosphor 3 can be formed with high precision, and the diffusion of the fluorescence can be performed. Can be structured so as to reduce the number of times. Furthermore, a complicated structure and high image quality utilizing the properties of the thin film 9 that is difficult to transmit X-rays and the thin film 10 that easily transmits X-rays can be achieved.
[0077]
FIG. 13 is a block diagram showing a configuration of the X-ray sensor according to the eighth embodiment of the present invention. In FIG. 13, reference numeral 11 denotes a precision processed surface of the substrate 1, and 12 denotes a rough processed surface of the substrate 1, and the phosphor 3 is provided on both the processed surfaces 11 and 12. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0078]
The operation of the X-ray sensor shown in FIG. 13 will be described. First, the X-rays are converted into light by the phosphor 3 formed on the substrate 1. The converted light is extracted by the photoelectric conversion unit 2 as an image signal. Here, the phosphor 3 is structured by being patterned by the precision processing surface 11 and the rough processing surface 12 on the substrate 1.
[0079]
FIG. 14 shows a configuration example of a structured pattern. As shown in FIG. 14, the phosphor 3 is formed on the substrate 1 on which the precision processing surface 11 and the rough processing surface 12 are formed. On the precision processing surface 11, the phosphor 3 is crystallized in a clean glass state. However, the crystal state of the phosphor 3 is poor on the rough processing surface 12 and the light transmittance is poor. Therefore, the diffusion of the fluorescent light is prevented at the rough processing surface 12 as a boundary, and an image with high resolution can be obtained.
[0080]
As described above, by increasing the controllability of the crystallinity of the phosphor 3 with respect to the substrate 1 due to the surface roughness of the substrate 1, diffusion of the fluorescent light can be prevented, and a high-resolution sensor can be provided.
[0081]
FIG. 15 is a block diagram showing the configuration of the X-ray sensor according to the ninth embodiment of the present invention. In FIG. 15, reference numeral 13 denotes a fluorescence conversion unit, on which a fluorescence conversion unit recognition mark 14 is provided. Reference numeral 15 denotes a photoelectric conversion unit recognition mark provided on the photoelectric conversion unit 2. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0082]
The operation of the X-ray sensor shown in FIG. 15 will be described. First, X-rays are converted into light by the fluorescence conversion unit 13. The converted light is extracted by the photoelectric conversion unit 2 as an image signal. Here, the fluorescence conversion unit 13 and the photoelectric conversion unit 2 are aligned by the fluorescence conversion unit recognition mark 14 provided on the fluorescence conversion unit 13 and the photoelectric conversion unit recognition mark 15 provided on the photoelectric conversion unit 2. .
[0083]
FIG. 16 shows an example of a process of aligning the fluorescence conversion unit 13 and the photoelectric conversion unit 2. In FIG. 16, two fluorescent conversion unit recognition marks 14 provided on the fluorescence conversion unit 13 and two photoelectric conversion unit recognition marks 15 provided on the photoelectric conversion unit 2 are provided. First, the fluorescence conversion unit 13 is gripped and positioned by the robot R1. Next, the fluorescence conversion unit 13 is moved by the robot R1 such that one of the fluorescence conversion unit recognition marks 14 is within the field of view of the fluorescence conversion unit recognition mark recognition camera C1. At this time, the position of the fluorescence conversion unit recognition mark 14 projected on the camera C1 and the movement amount of the robot R1 are recorded. Similarly, the robot R1 is moved to recognize the position of the other fluorescence conversion unit recognition mark 14, and the position and the amount of movement of the robot R1 are recorded.
[0084]
The photoelectric conversion unit 2 is held by the robot R2. Next, the robot R2 moves the photoelectric conversion unit 2 so that one of the photoelectric conversion unit recognition marks 15 is within the field of view of the camera C2 for photoelectric conversion unit recognition mark recognition. At this time, the position of the photoelectric conversion unit recognition mark 15 projected on the camera C2 and the movement amount of the robot R2 are recorded. The same processing is performed for the other photoelectric conversion unit recognition mark 15. Then, using the position of the fluorescence conversion unit recognition mark 14 projected on the camera C1, the movement amount of the robot R1, the position of the photoelectric conversion unit recognition mark 15 projected on the camera C2, and the movement amount of the robot R2, The position shift amount is calculated, and the fluorescence conversion unit 13 and the photoelectric conversion unit 2 are accurately positioned.
[0085]
As described above, by performing the alignment using the recognition marks 14 and 15 as a reference, it is possible to assemble with high accuracy and to provide a sensor with high resolution. In addition, the recognition marks 14 and 15 can be formed with the pattern of the fluorescence conversion unit 13 or the photoelectric conversion unit 2 at the same time to achieve higher accuracy.
[0086]
FIG. 17 is a block diagram showing the configuration of the X-ray sensor according to the tenth embodiment of the present invention. In FIG. 17, reference numeral 16 denotes a fluorescence output surface of the fluorescence conversion unit 13, reference numeral 17 denotes a fluorescence input surface of the photoelectric conversion unit 2, and reference numeral 18 denotes a bonding agent provided at a bonding portion between the photoelectric conversion unit 2 and the fluorescence conversion unit 13. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0087]
The operation of the X-ray sensor shown in FIG. 17 will be described. First, the X-rays are converted into light by the fluorescence conversion unit 13 and output to the fluorescence output surface 16. The converted light is extracted as an image signal by the photoelectric conversion unit 2 through the fluorescent light input surface 17. Here, the fluorescent output surface 16 and the fluorescent input surface 17 are in contact with each other, and the fluorescent conversion unit 13 and the photoelectric conversion unit 2 are bonded by a bonding agent 18 whose shape can be changed.
[0088]
In this manner, by bringing the fluorescent output surface 16 and the fluorescent input surface 17 into contact with each other, variations in the height of the fluorescent output surface 16 and the fluorescent input surface 17 are minimized. If there is a variation in height on the bonding surface where the bonding agent 18 is present, the variation is absorbed by the bonding agent 18 whose shape can be changed.
[0089]
As described above, by absorbing the variation in height between the fluorescence conversion unit 13 and the photoelectric conversion unit 2, it is possible to assemble with high accuracy even if the dimensions of the fluorescence conversion unit and the photoelectric conversion unit vary. Thus, a high-resolution sensor can be provided.
[0090]
FIG. 18 is a block diagram showing a configuration of the X-ray sensor according to the eleventh embodiment of the present invention. In FIG. 18, reference numeral 19 denotes a thermoplastic adhesive provided at a joint between the photoelectric conversion unit 2 and the fluorescence conversion unit 13. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0091]
The operation of the X-ray sensor shown in FIG. 18 will be described. First, the X-rays are converted into light by the fluorescence conversion unit 13 and output to the fluorescence output surface 16. The converted light is extracted as an image signal by the photoelectric conversion unit 2 through the fluorescent light input surface 17. Here, the fluorescent output surface 16 and the fluorescent input surface 17 are in contact with each other, and the fluorescent conversion unit 13 and the photoelectric conversion unit 2 are joined with a thermoplastic adhesive 19.
[0092]
In this manner, by bringing the fluorescent output surface 16 and the fluorescent input surface 17 into contact with each other, variations in the height of the fluorescent output surface 16 and the fluorescent input surface 17 are suppressed as much as possible. If there is a variation in height with respect to the joining surface where the thermoplastic adhesive 19 exists, the variation is absorbed by the thermoplastic adhesive 19.
[0093]
FIG. 19 shows a step of joining the fluorescence conversion unit 13 and the photoelectric conversion unit 2. First, a thermoplastic adhesive 19 is applied to the photoelectric conversion unit 2 so as to be thicker than the gap between the fluorescence conversion unit 13 and the photoelectric conversion unit 2. Next, the fluorescence conversion unit 13 is placed on the photoelectric conversion unit 2. Further, heat is applied while pressing the fluorescence conversion unit 13 against the photoelectric conversion unit 2. After the heating, the fluorescent output surface 16 and the fluorescent input surface 17 come into contact with each other.
[0094]
As described above, by absorbing the variation in the height between the fluorescence conversion unit 13 and the photoelectric conversion unit 2, even if the dimensions of the fluorescence conversion unit and the photoelectric conversion unit vary, the bonding, pressing, and heat curing are generally performed. With a simple construction method, high-precision assembly is possible, and a high-resolution sensor can be provided.
[0095]
FIG. 20 is a block diagram showing the configuration of the X-ray sensor according to the twelfth embodiment of the present invention. 20, reference numeral 20 denotes a phosphor cell, 21 denotes a CCD (charge coupled device), 22 denotes a pixel in the CCD, and 23 denotes a CCD cooling unit. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0096]
The operation of the X-ray sensor shown in FIG. 20 will be described. First, X-rays are converted into light in the phosphor cells 20 formed on the photoelectric conversion unit 13. The phosphor cells 20 are structured such that fluorescence is generated from each cell by means such as being isolated by a light shield. This light is received by the pixels 22 on the CCD 21 and the CCD 21 extracts image signals. At this time, the CCD 21 is cooled by the CCD cooling unit 23.
[0097]
As described above, by cooling the CCD 21, thermal noise in an electric circuit inside the CCD can be reduced. As a result, noise on the image signal can be reduced, and high gain amplification of the image signal becomes possible. Therefore, the sensitivity of the CCD 21 can be improved, and a sensor having a high resolution at the CCD pixel level can be provided.
[0098]
FIG. 21 is a block diagram showing the configuration of the X-ray sensor according to the thirteenth embodiment of the present invention. In FIG. 21, reference numeral 24 denotes a Peltier element provided close to the CCD 21. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0099]
The operation of the X-ray sensor shown in FIG. 21 will be described. First, X-rays are converted into light in the phosphor cells 20 formed on the photoelectric conversion unit 13. The phosphor cells 20 are structured such that fluorescence is generated from each cell by means such as being isolated by a light shield. This light is received by a pixel on the CCD 21 and an image signal is extracted by the CCD 21. At this time, the CCD 21 is cooled by the Peltier device 24.
[0100]
As described above, by cooling the CCD 21, thermal noise in the electric circuit inside the CCD 21 can be reduced. As a result, noise on the image signal can be reduced, and high gain amplification of the image signal becomes possible. Therefore, by improving the sensitivity of the CCD 21, it is possible to provide a sensor having a high resolution at the CCD pixel level. In particular, the Peltier device 24 is a solid-state cooling device based on a semiconductor and can be easily used in a factory or the like because it is smaller and has better maintainability than cooling by liquid nitrogen or the like.
[0101]
FIG. 22 is a block diagram showing the configuration of the X-ray sensor according to the fourteenth embodiment of the present invention. In FIG. 22, 25 is a scattered radiation preventing etching substrate, 26 is a substrate moving unit, and 27 is an X-ray image conversion unit. The same members as those already described are denoted by the same reference numerals and description thereof will be omitted.
[0102]
The operation of the X-ray sensor shown in FIG. 22 will be described. In this example, X-rays are imaged by the X-ray image conversion unit 27, and the scattered radiation preventing etching substrate 25 is moved by the substrate moving unit 26 according to the timing of image input. The scattered radiation preventing etching substrate 25 is shaped by etching, and can absorb a large amount of X-rays partially by changing the X-ray absorptivity at different portions of the processing pattern. As a result, the scattered X-rays generated from the inspection object can be removed by the scattered radiation preventing etching substrate 25.
[0103]
As described above, since scattered X-rays can be prevented, a high-quality image can be obtained. In addition, the scattered radiation preventing etching substrate 25 is shaped by etching, and is capable of forming a highly accurate pattern, thereby being able to cope with a fine object. Moreover, since the scattered radiation preventing etching substrate 25 is moved by the substrate moving unit 26, the pattern of the scattered radiation preventing etching substrate 25 and the position of the light receiving pattern of the X-ray image conversion unit 27 do not need to correspond. Therefore, even if the X-ray image converter 27 has a high resolution, it is possible to easily prevent scattered X-rays.
[0104]
FIG. 23 is a block diagram showing a configuration of the X-ray sensor according to the fifteenth embodiment of the present invention. In FIG. 23, reference numeral 28 denotes a scattered radiation preventing substance-formed substrate, and 29 denotes a scattered radiation preventing X-ray absorbing film provided on the X-ray incident side of the scattered radiation preventing substance-formed substrate 28. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted.
[0105]
The operation of the X-ray sensor shown in FIG. 23 will be described. In this example, X-rays are imaged by the X-ray image conversion unit 27, and the scattered radiation preventing substance film-forming substrate 28 on which the scattered radiation preventing X-ray absorbing film 29 is formed is changed according to the timing of image input. The moving unit 26 moves. The anti-scattering substance film-forming substrate 28 is formed by etching after the anti-scattering X-ray absorbing film 29 is formed, and the X-ray absorptance is changed at different portions of the processing pattern. Can absorb much X-rays. As a result, the scattered X-rays generated from the inspection object can be removed by the scattered radiation substance film-formed substrate 28.
[0106]
As described above, since scattered X-rays can be prevented, a high-quality image can be obtained. Further, the scattered radiation preventing X-ray absorption film 29 is formed by etching, and is capable of forming a highly accurate pattern, so that it can cope with a fine object. In addition, since the scattered radiation preventing substance deposition substrate 28 is moved by the substrate moving unit 26, it is not necessary to make the position of the pattern of the scattered radiation preventing X-ray absorption film 29 correspond to the position of the light receiving pattern of the X-ray image conversion unit 27. . Therefore, even if the X-ray image converter 27 has a high resolution, it is possible to easily prevent scattered X-rays. Further, by selecting the material of the scattered radiation preventing X-ray absorbing film 29, a scattered X-ray preventing means suitable for the purpose can be created.
[0107]
FIG. 24 is a block diagram showing the configuration of an embodiment of the X-ray inspection apparatus according to the present invention. In FIG. 24, reference numeral 30 denotes an X-ray emitting unit. Reference numeral 31 denotes an object to be inspected. The same members as those already described are denoted by the same reference numerals, and description thereof will be omitted. Further, the scattered radiation preventing etching substrate 25 and the X-ray image converter 27 are located at a close distance to the object 31, and the scattered radiation preventing etching substrate 25 is located between the X-ray emitting unit 30 and the X-ray image converter 27. ing.
[0108]
The operation of the X-ray inspection apparatus shown in FIG. 24 will be described. First, X-rays are radiated from the X-ray radiating unit 30 and the object 31 is transmitted. Next, the X-rays transmitted through the diffusion-ray preventing etching substrate 25 are imaged by the X-ray image conversion unit 27, and the scattering-ray preventing etching substrate 25 is moved by the substrate moving unit 26 according to the timing of image input. The scattered radiation preventing etching substrate 25 is shaped by etching, and by changing the X-ray absorption at different portions of the processing pattern, it is possible to partially absorb a large amount of X-rays. As a result, scattered X-rays generated from the inspection object 31 can be removed by the scattered radiation preventing etching substrate 25.
[0109]
As described above, since scattered X-rays can be prevented, a high-quality image can be obtained. The scattered radiation preventing etching substrate 25 is shaped by etching, and is capable of forming a highly accurate pattern. Moreover, since the scattered radiation preventing etching substrate 25 is moved by the substrate moving unit 26, it is not necessary to make the pattern of the scattered radiation preventing etching substrate 25 correspond to the position of the light receiving pattern of the X-ray image converter 27. Therefore, even if the X-ray image converter 27 has a high resolution, it is possible to easily prevent scattered X-rays.
[0110]
In particular, when the focal size of the X-ray radiating unit 30 is large, it is necessary to suppress image blur in order to perform a precise inspection, and the X-ray image converting unit 27 needs to be at a close distance to the object 31. In this case, since the X-ray image conversion unit 27 is located at a close distance to the object 31, the X-ray image conversion unit 27 is easily affected by scattered X-rays generated from the object 31. Therefore, the effect of the scattered radiation removing effect is great.
[0117]
【The invention's effect】
As described above, according to the present invention,By forming a thin film having a property of hardly transmitting X-rays and a thin film having a property of easily transmitting X-rays on the substrate, the shape of the phosphor material can be formed with high precision, and the diffusion of the fluorescent light can be reduced. This makes it possible to construct such a structure. Furthermore, a complex structure utilizing the properties of a thin film that is difficult to transmit X-rays and a thin film that easily transmits X-raysCan be produced,High image quality can be achieved.
[0118]
Also, by processing any part of the substrate to have a rougher surface roughness than other parts and forming the phosphor material on the substrate, the surface roughness of the substrate causes the formation of the crystal of the phosphor material with respect to the substrate. Controllability can be improved, diffusion of fluorescence can be prevented, and a high-resolution sensor can be provided.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an X-ray sensor according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram showing an example of a structured phosphor pattern in the X-ray sensor according to the first embodiment of the present invention.
FIG. 3 is a block diagram showing a configuration of an X-ray sensor according to a second embodiment of the present invention.
FIG. 4 is a configuration diagram showing an example of a structured phosphor pattern in an X-ray sensor according to a second embodiment of the present invention.
FIG. 5 is an explanatory view showing a state in which a phosphor or a thin film is formed by sputtering for explaining a third embodiment of the present invention.
FIG. 6 is a block diagram illustrating a configuration of an X-ray sensor according to a fourth embodiment of the present invention.
FIG. 7 is a block diagram illustrating a configuration of an X-ray sensor according to a fifth embodiment of the present invention.
FIG. 8 is a configuration diagram showing an example of a structured phosphor pattern in an X-ray sensor according to a fifth embodiment of the present invention.
FIG. 9 is a block diagram showing a configuration of an X-ray sensor according to a sixth embodiment of the present invention.
FIG. 10 is a configuration diagram showing an example of a structured phosphor pattern in an X-ray sensor according to a sixth embodiment of the present invention.
FIG. 11 is a block diagram illustrating a configuration of an X-ray sensor according to a seventh embodiment of the present invention.
FIG. 12 is a configuration diagram showing an example of a structured phosphor pattern in an X-ray sensor according to a seventh embodiment of the present invention.
FIG. 13 is a block diagram showing a configuration of an X-ray sensor according to an eighth embodiment of the present invention.
FIG. 14 is a configuration diagram showing an example of a structured phosphor pattern in an X-ray sensor according to an eighth embodiment of the present invention.
FIG. 15 is a block diagram showing a configuration of an X-ray sensor according to a ninth embodiment of the present invention.
FIG. 16 is an explanatory view showing an example of a manufacturing process of the X-ray sensor according to the ninth embodiment of the present invention.
FIG. 17 is a block diagram showing a configuration of an X-ray sensor according to a tenth embodiment of the present invention.
FIG. 18 is a block diagram illustrating a configuration of an X-ray sensor according to an eleventh embodiment of the present invention.
FIG. 19 is an explanatory view showing an example of the manufacturing process of the X-ray sensor according to the eleventh embodiment of the present invention.
FIG. 20 is a block diagram showing a configuration of an X-ray sensor according to a twelfth embodiment of the present invention.
FIG. 21 is a block diagram showing a configuration of an X-ray sensor according to a thirteenth embodiment of the present invention.
FIG. 22 is a block diagram illustrating a configuration of an X-ray sensor according to a fourteenth embodiment of the present invention.
FIG. 23 is a block diagram showing a configuration of an X-ray sensor according to a fifteenth embodiment of the present invention.
FIG. 24 is a block diagram showing a configuration of an X-ray inspection apparatus according to the present invention.
FIG. 25 is a block diagram showing a configuration of a conventional X-ray sensor.
26A and 26B are explanatory diagrams of a phosphor having a fiber-like structure, wherein FIG. 26A is a cross-sectional view of the phosphor, and FIG. 26B is a schematic diagram illustrating a state in which fluorescence proceeds in the phosphor.
27A and 27B are explanatory diagrams for explaining the concept of image magnification imaging using X-rays and blurring of an image generated due to the focal size of the X-ray tube. FIG. FIG. 2B is a diagram illustrating imaging with an X-ray tube having a small focal size.
[Explanation of symbols]
1 substrate
2 Photoelectric conversion unit
3 phosphor
4 Thin film
5 Target
6 high energy particles
7 Target particles
8 pixels
9 X-ray shielding thin film
10. X-ray transparent thin film
11 Precision machined surface of substrate
12 Rough surface of substrate
13 Fluorescence converter
14 Recognition mark of fluorescence conversion part
15 Photoelectric conversion unit recognition mark
16 Fluorescent output surface
17 Fluorescent input surface
18 Bonding agent
19 Thermoplastic adhesive
20 phosphor cell
21 CCD
22 CCD pixels
23 CCD cooling unit
24 Peltier element
25 Scattered radiation prevention etching substrate
26 Substrate moving unit
27 X-ray image converter
28 Anti-scattering substance deposition substrate
29 X-ray absorption film to prevent scattered radiation
30 X-ray emitting unit
31 Objects to be inspected

Claims (4)

An X-ray sensor comprising: a fluorescence conversion unit configured to convert X- rays into light; and a photoelectric conversion unit configured to convert light generated from the fluorescence conversion unit into an image signal.
As the fluorescence conversion means, a film having a property of hardly transmitting X-rays and a film having a property of easily transmitting X-rays are provided in parallel in the direction perpendicular to the X-ray incident direction on the substrate surface, and in contact with the film, An X-ray sensor comprising a phosphor layer provided in a direction perpendicular to an X-ray incident direction . An X-ray sensor comprising: a fluorescence conversion unit configured to convert X-rays into light; and a photoelectric conversion unit configured to convert light generated from the fluorescence conversion unit into an image signal.
Examples fluorescence conversion means, X-rays sensor you wherein the arbitrary portion of the substrate has been machined rough surface roughness than other portions, to form a phosphor material on the substrate. In an X-ray inspection apparatus that performs an X-ray inspection on an inspection object using an X-ray sensor, the X-ray sensor has a structure in which a fluorescent substance is formed on a substrate and converts X-rays into light. And a photoelectric conversion means for converting light generated from the fluorescence conversion means into an image signal, and as the fluorescence conversion means, a film having a property of hardly transmitting X-rays on the substrate surface and an X-ray. An X-ray sensor having a film that easily transmits light was provided in parallel in the direction perpendicular to the X-ray incident direction, and a phosphor layer was provided in contact with the film and provided in a direction perpendicular to the X-ray incident direction . An X-ray inspection apparatus , characterized in that: In an X-ray inspection apparatus that performs an X-ray inspection on an inspection object using an X-ray sensor, the X-ray sensor has a structure in which a fluorescent substance is formed on a substrate and converts X-rays into light. And a photoelectric conversion unit for converting light generated from the fluorescence conversion unit into an image signal, and as the fluorescence conversion unit, an arbitrary portion of the substrate has a surface roughness greater than other portions. An X-ray inspection apparatus characterized by mounting an X-ray sensor which is processed and forms a phosphor substance on a substrate thereof .

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