JP4127742B2 - X-ray inspection equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray inspection apparatus that performs X-ray inspection on a sample by irradiating the sample with X-rays and imaging X-rays transmitted through the sample.
[0002]
[Prior art]
For example, an X-ray inspection apparatus having a microfocus X-ray tube (X-ray source) is known as an apparatus for performing nondestructive inspection of a sample. The microfocus X-ray tube includes a housing having an X-ray exit window and a vacuum sealed inside, an electron gun that generates and emits electrons in the housing, and an electron beam from the electron gun. And a target having a target surface formed obliquely with respect to each of the X-ray exit windows (reflection type target), and an X-ray is generated when an electron beam from the electron gun collides with the target surface. The X-ray is emitted to the outside through the X-ray emission window. In the X-ray inspection apparatus having the microfocus X-ray tube, a sample as a test object is arranged facing the X-ray emission window, and X-rays transmitted through the sample are detected by an X-ray camera (X-ray imaging apparatus). By imaging, non-destructive inspection of the sample by X-ray is performed.
[0003]
Further, the X-ray inspection apparatus further includes a sample holding / moving means and an X-ray camera moving means (in which the sample holding means and the X-ray camera for holding the sample can be moved in a direction in which the X-ray inspection window is in contact with and away from the X-ray exit window). X-ray imaging device moving means), each of which is configured to enlarge or reduce the image of the sample imaged by the X-ray camera by moving the sample by the sample holding and moving means or moving the X-ray camera by the X-ray camera moving means. Has been made.
[0004]
[Problems to be solved by the invention]
By the way, recently, research for enlarging or reducing the sample image without mechanically moving the sample or the X-ray camera in the same direction is also underway.
[0005]
Therefore, an object of the present invention is to provide an X-ray inspection apparatus capable of enlarging or reducing a sample image with a new configuration different from the conventional one.
[0006]
[Means for Solving the Problems]
The X-ray inspection apparatus of the present invention has a target formed obliquely with respect to each of an incident electron beam and an X-ray exit window, and generates an X-ray when the electron beam collides with the target. X-ray source that emits through an X-ray exit window and an electron beam that can be deflected in a first direction that makes contact with and away from the X-ray exit window at least in a plane including the electron beam. A specimen deflected by X-rays emitted through the beam deflection means and the X-ray exit window is held, and the specimen is at least moved in the X-ray movement direction when the electron beam is deflected in the first direction. A sample holding / moving means capable of moving in the second direction, an X-ray imaging device for imaging X-rays transmitted through the sample, and an electron beam deflecting means to deflect the electron beam in the first direction. Control holding and moving means And a controller for moving the sample in the second direction in response to an amount corresponding to the deflection in the first direction of the electron beam, equipped with a.
[0007]
According to such an X-ray inspection apparatus according to the present invention, X-rays are generated when an electron beam collides with a target in an X-ray source, and the X-rays are emitted through an X-ray emission window. The X-rays emitted through the X-ray emission window irradiate the sample held by the sample holding / moving means, and the X-rays transmitted through the sample are imaged by the X-ray imaging device, and the X-rays to the sample are obtained. Inspection is carried out. Here, the electron beam deflecting unit is controlled by the controller, and the electron beam deflecting unit deflects the electron beam toward the target in a first direction in which the electron beam is approached to and separated from the X-ray emission window in a plane including the electron beam. Then, the collision position of the electron beam with respect to the target is moved in the first direction, and the X-line length between the collision position, the sample, and the X-ray imaging apparatus is changed. An enlarged image or a reduced image can be obtained. At this time, the sample holding / moving means is controlled by the controller, and the sample holding / moving means causes the sample to move in the second direction which is the X-ray moving direction when the electron beam is deflected in the first direction. Since the sample is moved in accordance with the amount corresponding to the deflection in the first direction, the same position of the sample can be irradiated with X-rays, and the output of the X-ray imaging apparatus includes an enlarged image or a reduced image including the same position of the sample Is obtained.
[0008]
Here, the X-ray imaging apparatus is provided with X-ray imaging apparatus moving means that can move at least in the second direction, and the controller controls the sample holding movement means and the X-ray imaging apparatus moving means, respectively, to control the first of the electron beams. It is preferable that the sample and the X-ray imaging apparatus are respectively moved in the second direction according to the amount corresponding to the deflection in one direction.
[0009]
When such a configuration is adopted, the controller also controls the X-ray imaging device moving means, and the X-ray imaging device moving means controls the X-ray imaging device to an amount corresponding to the deflection of the electron beam in the first direction. Accordingly, since it is moved in the second direction, an enlarged image or a reduced image of the same position of the sample is obtained as the output of the X-ray imaging apparatus.
[0010]
The electron beam deflecting means can further deflect the electron beam in a third direction orthogonal to the first direction, and the sample holding and moving means can be used when the sample is deflected in the third direction. The controller further includes a deterioration determining means for determining the deterioration of the target. When the deterioration of the target is determined, the controller controls the electron beam deflecting means. It is preferable that the electron beam is deflected in the third direction and the sample is moved in the third direction according to the amount corresponding to the deflection of the electron beam in the third direction by controlling the sample holding and moving means.
[0011]
When such a configuration is adopted, when deterioration of the target is determined by the deterioration determining means included in the controller, the electron beam deflecting means is controlled by the controller, and the electron beam deflecting means causes the electron beam toward the target to be emitted. Further deflection in the third direction orthogonal to the first direction causes the collision position of the electron beam to the target to move from the degraded position to the third direction, and this movement does not change the X-line length. As the output of the apparatus, a clear enlarged image or reduced image of the sample can be obtained at the same magnification. At this time, the sample holding / moving means is controlled by the controller, and the sample is further moved in the third direction according to the amount corresponding to the deflection of the electron beam in the third direction by the sample holding / moving means. Can be irradiated with X-rays, and as an output of the X-ray imaging apparatus, a clear enlarged image or reduced image including the same position of the sample can be obtained at the same magnification.
[0012]
Further, the X-ray imaging apparatus moving means can further move the X-ray imaging apparatus in the third direction, and when the controller determines the target deterioration, the controller controls the electron beam deflecting means to move the electron beam in the third direction. And the sample holding / moving means and the X-ray imaging device moving means are controlled to move the sample and the X-ray imaging device in the third direction according to the amount corresponding to the deflection of the electron beam in the third direction. It is preferable that the configuration be
[0013]
In the case of adopting such a configuration, when the deterioration determination unit included in the controller determines the deterioration of the target, the controller also controls the X-ray imaging device moving unit. Since the imaging device is further moved in the third direction according to the amount corresponding to the deflection of the electron beam in the third direction, the output of the X-ray imaging device includes a clear enlarged image of the same position of the sample or Reduced video is obtained at the same magnification.
[0014]
Here, various determinations of target deterioration by the controller are conceivable. For example, it is effective to determine based on the darkness of the sample image as the output of the X-ray imaging apparatus or the value of the X-ray detector.
[0015]
Various electron beam deflecting means are conceivable. For example, an electrostatic deflection electrode or an electromagnetic deflection electrode can be adopted. In the case of the electrostatic deflection electrode, the X-ray source can be made compact because the electrostatic deflection electrode can be arranged inside the X-ray source. Further, when the electromagnetic deflection coil is used, the electromagnetic deflection coil can be disposed outside the X-ray source, so that the mounting adjustment of the electromagnetic deflection coil is facilitated.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an X-ray inspection apparatus according to the invention will be described with reference to the accompanying drawings. Note that, in each drawing, the same elements are denoted by the same reference numerals, and redundant description is omitted.
[0017]
FIG. 1 is a block diagram showing an X-ray inspection apparatus according to the first embodiment. The X-ray inspection apparatus according to the present embodiment is used when, for example, a sample 1 as a test object is nondestructively inspected. is there.
[0018]
The X-ray inspection apparatus is generally seen through a microfocus X-ray tube (X-ray source; hereinafter simply referred to as an X-ray tube) 2 for generating and emitting X-rays 50 and an X-ray 50 as shown in FIG. A sample manipulator (sample holding / moving means) 3 that allows the sample 1 to be held and move the sample 1 in a plane orthogonal to the X-ray 50 and in a direction along the X-ray 50, and the sample 1. An X-ray camera (X-ray imaging apparatus) 4 that images the X-ray 50 to be moved, and an X-ray camera that can move the X-ray camera 4 in a plane orthogonal to the X-ray 50 and in a direction along the X-ray 50 Manipulator (X-ray imaging device moving means) 5, sample monitor monitor device 6 for displaying an image of the sample 1 imaged by the X-ray camera 4, and the X-ray tube 8 for enlarging or reducing the sample image Electrostatic deflection electrode (electron beam deflection) Includes a stage) 8.
[0019]
As shown in FIG. 2, the X-ray tube 2 includes a housing 9 whose inside is vacuum-sealed. In the housing 9, an electron gun 10 that generates and emits electrons, and an electron gun 10 from the electron gun 10. A reflective target (anode) 11 that generates X-rays 50 when the electron beam 45 collides is installed.
[0020]
The electron gun 10 includes a cathode (not shown) that generates and emits electrons 45 when heated by a heater, and first and second grid electrodes 10b and 10c that accelerate and focus the electrons 45 emitted from the cathode. Prepare. An electron beam controller 20 for supplying a predetermined voltage is connected to the cathode of the electron gun 10 and the first and second grid electrodes 10b and 10c via pins 10a exposed to the outside (see FIG. 1). The electron beam controller 20 controls the amount of electrons generated by the electron gun 10 by controlling the voltage supplied to the electron gun 10.
[0021]
As shown in FIG. 2, a focusing electrode 9b for further focusing electrons 45 directed to the target 11 is disposed between the electron gun 10 and the target 11, and an electron path downstream of the focusing electrode 9b is shown in FIG. 2 and FIG. 3, the target 11 is installed. The target 11 receives electrons 45 from the electron gun 10 at the target surface 11a and generates X-rays 50. The target surface 11a has the incident electrons 45 and the emitted X-rays 50 orthogonal to each other. To be inclined.
[0022]
As shown in FIG. 1, a high voltage power source 19 that supplies a positive high voltage is connected to the target 11. The high voltage power source 19 is generated at the target 11 by controlling the voltage of the high voltage power source 19. An X-ray controller 21 that controls the X-ray dose is connected.
[0023]
As shown in FIGS. 1 and 2, an X-ray emission window 9 a is provided at the emission destination of the X-ray 50 in the housing 9. The X-ray emission window 9a is a window for emitting the X-rays 50 generated at the target 11 to the outside, and is constituted by, for example, a plate made of a Be material that is an X-ray transmission material.
[0024]
In particular, in the present embodiment, the X-ray tube 2 having the above configuration is provided with an electrostatic deflection electrode 8 as shown in FIGS. The electrostatic deflection electrode 8 is used when enlarging or reducing the sample image, or when moving the electron collision position when the electron collision position of the target surface 11a deteriorates. Placed inside.
[0025]
As shown in FIG. 3, the electrostatic deflection electrode 8 is composed of four plate-like electrodes arranged so as to surround the electron beam 45, and the two electrodes 8a and 8b forming a pair of the electrodes are an electron. 2 is arranged opposite to the first direction A (vertical direction in FIG. 2) as the direction of contact with and away from the X-ray exit window 9a within the plane including the beam 45 with the electron beam 45 therebetween, forming another pair. The two electrodes 8c and 8d are arranged to face each other with the electron beam 45 interposed therebetween in a third direction C (a direction perpendicular to the paper surface in FIG. 2) as a direction orthogonal to the A direction.
[0026]
Thus, since the electrostatic deflection electrode 8 is disposed inside the X-ray tube 2, the X-ray tube 2 is made compact and space saving is achieved.
[0027]
As shown in FIG. 1, a deflection electrode control circuit 22 is connected to the electrostatic deflection electrode 8. When the electrostatic field by the electrostatic deflection electrodes 8a and 8b is controlled by the deflection electrode control circuit 22, the electron beam 45 is deflected in the first direction A, and the electrostatic field by the electrostatic deflection electrodes 8c and 8d is controlled. Then, the electron beam 45 is deflected in the third direction C. By combining these deflection directions, the electron beam 45 can be deflected in all directions within the plane including the first direction A and the third direction C. Further, the amount of deflection of the electron beam 45 is also controlled by controlling the electrostatic field. Further, the electron beam 45 goes straight when not energized.
[0028]
The sample manipulator 3 has a known structure, and is arranged in the vicinity of the X-ray exit window 9a of the X-ray tube 2 as shown in FIG. The sample manipulator 3 holds a sample 1 disposed opposite to the X-ray exit window 9a by a clamper 3a, and in this state, moves the sample 1 in a plane perpendicular to the X-ray 50, That is, with reference to FIG. 1, in the second direction (the left-right direction in the figure) B as the moving direction of the X-ray 50 when the electron beam 45 is deflected in the first direction A, and in the third direction C described above. A mechanism is provided that moves, and a mechanism that moves in a direction that moves toward and away from the X-ray exit window 9a (direction along the X-ray 50), that is, a mechanism that moves in the first direction A. The sample manipulator 3 is connected to a sample moving drive circuit 23 for controlling the moving direction and moving amount of the sample 1.
[0029]
The X-ray camera 4 is arranged behind the sample 1 by a predetermined distance and is held by an X-ray camera manipulator 5. The X-ray camera manipulator 5 has the same configuration as the sample manipulator 3 and includes a mechanism for moving the X-ray camera 4 in the first, second, and third directions A, B, and C. The X-ray camera manipulator 5 is connected to an X-ray camera moving drive circuit 24 that controls the moving direction and the moving amount of the X-ray camera 4.
[0030]
The X-ray camera 4 is connected to an image processing device 25 that performs predetermined image processing and outputs it as a video signal, and a monitor device 6 is connected to the image processing device 25. The monitor device 6 inputs a display 6a that displays a sample image as an output of the X-ray camera 4 and a magnification rate and a reduction rate of the sample image when the sample image is enlarged or reduced by the action of the electrostatic deflection electrode 8. And a switch 6b. The monitor device 6 also includes a switch 6c for driving the sample manipulator 3 to move in the second and third directions B and C, a sample manipulator 3, and an X-ray camera manipulator to project a desired position of the sample 1. 5 is driven to move the sample 1 and the X-ray camera 4 in the first direction A, and a switch 6d for inputting a magnification rate and a reduction rate of the sample image when the sample image is enlarged or reduced.
[0031]
In addition, the X-ray inspection apparatus according to the present embodiment further responds to a signal from the monitor device 6 in response to an electron beam controller 20, an X-ray controller 21, a deflection electrode control circuit 22, a sample moving drive circuit 23, and an X-ray camera. A predetermined signal is sent to the driving circuit 24 for movement, and the enlargement or reduction of the sample image is controlled in a predetermined manner, and the brightness level of the sample image displayed on the display 6a of the monitor device 6 is constantly monitored, and according to this level. A controller (CPU) 7 composed of a microcomputer for performing predetermined control is provided.
[0032]
The controller 7 includes target deterioration determination means 7a that determines target deterioration in accordance with the brightness level of the sample image that is constantly monitored. The determination of the deterioration is made, for example, by comparing the brightness of the normal image with the brightness of the image monitored at the present time and the comparison exceeds a predetermined allowable range.
[0033]
The controller 7 also has a function of giving a command for controlling the amount of electrons generated by the electron gun 10 to the electron beam controller 20 and controls an X-ray dose generated by the target 11 for the X-ray controller 21. A function of giving a command, and a function of giving a command for controlling the deflection direction and the deflection amount of the electron beam 45 to the deflection electrode control circuit 22; This deflection direction and deflection amount control command is sent when the sample image is enlarged or reduced, and is also sent when the above-described deterioration of the target 11 is determined.
[0034]
Further, the controller 7 has a function of giving a command for controlling the moving direction and moving amount of the sample 1 to the sample moving drive circuit 23, and to the X-ray camera moving drive circuit 24. 4 has a function of sending a command for controlling the moving direction and moving amount. The control command for the moving direction and moving amount of the sample 1 and the X-ray camera 4 is sent when the sample image is enlarged or reduced, and is also sent when the deterioration of the target 11 is determined.
[0035]
The controller 7 is connected to a ROM 26 for storing a program for performing processing operations, which will be described later, various data tables, arithmetic expressions, etc. in the form of fixed data, and a RAM 27 for temporarily storing the arithmetic results. Connected to enable input / output.
[0036]
Next, the operation of the X-ray inspection apparatus configured as described above will be described. Under normal conditions, the electrostatic deflection electrode 8 is in an off state, and the operation is performed at a magnification of 1. In this case, first, a negative voltage is supplied to the first grid electrode 10b, a ground potential is supplied to the second grid electrode 10c, and a positive high voltage is supplied to the target 11, and the heater is heated in this state. Then, electrons 45 are emitted from the cathode, and the electrons 45 are accelerated and focused through the first and second grid electrodes 10b and 10c, and further focused and incident on the target surface 11a through the focusing electrode 9b. . At this time, as described above, since the electrostatic deflection electrode 8 is in the OFF state, the electron beam 45 travels straight and is focused on the target surface 11a. X-rays 50 are generated by the collision of the electrons 45 against the target surface 11a, and the X-rays 50 are emitted out of the X-ray tube 2 through the X-ray emission window 9a.
[0037]
The X-ray 50 passes through a predetermined portion of the sample 1 held by the sample manipulator 3, and the X-ray camera 50 picks up the transmitted X-ray 50 with the X-ray camera 4 so that a sample image at a magnification of 1 is displayed on the display 6a. The image is projected and an X-ray examination is performed.
[0038]
Here, when the other part of the sample 1 is to be inspected, the sample manipulator 3 is driven by the switch 6 c and moved so that the other part of the sample 1 is positioned on the X-ray 50.
[0039]
Next, a case where the sample image displayed on the display 6a is enlarged or reduced will be described with reference to FIGS. First, in step 1 shown in FIG. 4, the sample image is enlarged or reduced by the electrostatic deflection electrode 8 which is the feature of this embodiment, or the sample by the conventional sample manipulator 3 or X-ray camera manipulator 4 is used. 1. It is determined whether or not the X-ray camera 4 is moved in the first direction. This determination is made based on whether an instruction for enlarging or reducing the sample image is given by the switch 6b or the switch 6d.
[0040]
If it is determined that the instruction to enlarge or reduce the sample image has been issued by the switch 6d, the processing procedure of the conventional method is performed, and the process proceeds to step 9 shown in FIG. 5. In step 9, it is determined whether or not the instruction is for enlargement. If it is determined that the instruction is an enlargement instruction, the process proceeds to step 10, where the distance between the sample 1 and the X-ray tube 2 is calculated based on the current position of the sample 1, and the calculated value is used as the basis. If it is determined whether or not the sample 1 can approach the X-ray tube 2, and if it is determined that the sample 1 can approach the X-ray tube 2, the process proceeds to step 11. In step 11, the sample manipulator 3 is driven. Then, the sample 1 is moved in the direction approaching the X-ray tube 2 so that the sample image has the enlargement ratio.
[0041]
On the other hand, if it is determined in step 10 that the sample 1 cannot approach the X-ray tube 2, the process proceeds to step 12, and in step 12, the sample 1 and the X-ray camera 4 are based on the current position of the sample 1. If the X-ray camera 4 can be separated from the sample 1 based on the calculated value, and if it is determined that the X-ray camera 4 can be separated from the sample 1, step 13 is performed. In step 13, the X-ray camera manipulator 5 is driven, and the X-ray camera 4 is moved away from the sample 1 so that the sample image has the enlargement ratio.
[0042]
Here, the amount of movement of the sample 1 by the sample manipulator 3 and the amount of movement of the X-ray camera 4 by the X-ray camera manipulator 5 are previously stored in the ROM 26 corresponding to the magnification rate so as to obtain a sample image of the designated magnification rate. Is stored in the data table.
[0043]
If it is determined in step 12 that the X-ray camera 4 cannot be separated from the sample 1, the process proceeds to step 14, and in step 14, the sample image should be enlarged or reduced by the electrostatic deflection electrode 8. Is displayed on the display 6a.
[0044]
On the other hand, if it is determined in step 9 that the instruction is not an enlargement instruction, that is, a reduction instruction, the process proceeds to step 15, and in step 15, the sample 1 and the X-ray tube 2 are based on the current position of the sample 1. , And based on this calculated value, it is determined whether or not the sample 1 can be separated from the X-ray tube 2. If it is determined that the sample 1 can be separated from the X-ray tube 2, In step 16, the sample manipulator 3 is driven, and the sample 1 is moved in the direction away from the X-ray tube 2 so that the sample image has the reduction ratio.
[0045]
On the other hand, if it is determined in step 15 that the sample 1 cannot be separated from the X-ray tube 2, the process proceeds to step 17, and in step 17, the sample 1 and the X-ray camera 4 are based on the current position of the sample 1. , And whether or not the X-ray camera 4 can approach the sample 1 is determined based on the calculated value. If it is determined that the X-ray camera 4 can approach the sample 1, the process proceeds to step 18. In step 18, the X-ray camera manipulator 5 is driven, and the X-ray camera 4 is moved in the direction approaching the sample 1 so that the sample image becomes the reduction ratio.
[0046]
Here, the amount of movement of the sample 1 by the sample manipulator 3 and the amount of movement of the X-ray camera 4 by the X-ray camera manipulator 5 are such that the sample image of the instructed reduction rate is the same as in the case of the enlargement rate. Corresponding to the reduction ratio, it is stored in advance in the data table of the ROM 26.
[0047]
If it is determined in step 17 that the X-ray camera 4 cannot approach the sample 1, the process proceeds to step 14 as in the case of enlargement.
[0048]
On the other hand, if it is determined in step 1 shown in FIG. 4 that an instruction for enlarging or reducing the sample image has been issued by the switch 6b, a processing procedure of a new method by the electrostatic deflection electrode 8 which is a feature of the present embodiment, Become. In this case, the process proceeds to step 2, and in step 2, it is determined whether or not the instruction is for enlargement. If it is determined that the instruction is for enlargement, the process proceeds to step 3 and the control of the deflection electrode control circuit 22 is performed in step 3. By controlling the electrostatic field by the electrostatic deflection electrodes 8a and 8b, the electron beam 45 is deflected to the side closer to the X-ray exit window 9a in the first direction A (the lower side in the figure) as shown in FIG. . This deflection amount is stored in advance in the data table of the ROM 26 corresponding to the enlargement ratio so as to obtain a sample image of the instructed enlargement ratio.
[0049]
Thereby, the collision position of the electron beam 45 with respect to the target surface 11a also moves to the same direction side. In this deflection, since the collision position of the electron beam 45 with respect to the target surface 11a is moved to the side closer to the X-ray exit window 9a in the first direction A, the X-line length is shortened. Enlarged at a magnification.
[0050]
In this way, the collision position of the electron beam 45 with respect to the target surface 11a is moved to the side closer to the X-ray emission window 9a in the first direction A. However, the irradiation position of the X-ray 50 on the sample 1 is the second position. Since it moves to one side (right side in FIG. 1) in the direction B and the same position is no longer irradiated, in step 4, the sample manipulator 3 is driven to irradiate the second position of the sample 1 so that the same position of the sample 1 is irradiated. Move to one side in direction B. Further, since the X-ray camera 4 does not capture the same position of the sample 1 as it is, the X-ray camera is driven so that the X-ray camera manipulator 5 is driven and the same position of the sample 1 is imaged in Step 5. 4 is moved to one side in the second direction. The amount of movement when the sample 1 is expanded by the sample manipulator 3 and the amount of movement when the X-ray camera 4 is expanded by the X-ray camera manipulator 5 are the amounts of deflection of the electron beam 45 by the electrostatic deflection electrodes 8a and 8b. Correspondingly, it is stored in advance in the data table of the ROM 26.
[0051]
On the other hand, if it is determined in step 2 that the instruction is not an enlargement instruction, that is, a reduction instruction, the process proceeds to step 6, and in step 6, the electrostatic field generated by the electrostatic deflection electrodes 8 a and 8 b is controlled by the deflection electrode control circuit 22. And the electron beam 45 is deflected to the side away from the X-ray exit window 9a in the first direction A (upper side in the figure) as shown in FIG. This deflection amount is stored in advance in the data table of the ROM 26 so as to correspond to the reduction rate so as to obtain a sample image with the specified reduction rate.
[0052]
Thereby, the collision position of the electron beam 45 with respect to the target surface 11a also moves to the same direction side. In this deflection, since the collision position of the electron beam 45 with respect to the target surface 11a is moved to the side away from the X-ray exit window 9a in the first direction A, the X-line length becomes long, and thus the sample image is instructed. Reduced by magnification.
[0053]
In this way, the collision position of the electron beam 45 with respect to the target surface 11a is moved to the side away from the X-ray emission window 9a in the first direction A. However, the irradiation position of the X-ray 50 with respect to the sample 1 remains in the second direction. Since it moves to the other side of B (the left side in FIG. 1) and the same position is no longer irradiated, in step 7, the sample manipulator 3 is driven so that the same position of the sample 1 is irradiated in the second direction. Move to the other side of B. Further, since the X-ray camera 4 does not capture the same position of the sample 1 as it is, the X-ray camera is driven so that the X-ray camera manipulator 5 is driven and the same position of the sample 1 is imaged in Step 8. 4 is moved to the other side in the second direction. The amount of movement when the sample 1 is reduced by the sample manipulator 3 and the amount of movement when the X-ray camera 4 is reduced by the X-ray camera manipulator 5 are the amounts of deflection of the electron beam 45 by the electrostatic deflection electrodes 8a and 8b. Correspondingly, it is stored in advance in the data table of the ROM 26.
[0054]
Thus, in the present embodiment, the controller 7 controls the electrostatic deflection electrodes 8a and 8b, and the electrostatic deflection electrodes 8a and 8b deflect the electron beam 45 toward the target 11 in the first direction. Since the collision position of the electron beam 45 with respect to the target 11 is moved in the first direction A and the X-line length is changed, an enlarged image or a reduced image of the sample 1 can be obtained on the display 6a. At this time, the sample manipulator 3 is controlled by the controller 7, and the sample manipulator 3 moves the sample 1 in the second direction B according to the amount corresponding to the deflection of the electron beam 45 in the first direction A. Therefore, the same position of the sample 1 can be irradiated with the X-ray 50, and the X-ray manipulator 5 is also controlled by the controller 7. The X-ray manipulator 5 causes the X-ray camera 4 to Since the display 6a is moved in the second direction B according to the amount corresponding to the deflection in the first direction A, an enlarged image or a reduced image of the same position of the sample 1 can be obtained.
[0055]
Next, the case of increasing the X-ray dose will be described with reference to FIG. First, in step 1, the brightness of the normal image and the brightness of the currently monitored image are compared by the controller 7, and if this comparison exceeds a predetermined allowable range, the process proceeds to step 2, and in step 2, the electron beam controller It is determined whether or not the amount of electrons generated in the electron gun 10 can be increased by the control of 20, and if it is determined that the amount can be increased, the amount of electrons is increased by the control of the electron beam controller 20 in step 3, thereby Increase x-ray dose.
[0056]
On the other hand, if it is determined in step 2 that the amount of electrons generated by the electron gun 10 cannot be increased by the control of the electron beam controller 20, the process proceeds to step 4, and the target 11 is controlled by the X-ray controller 21 in step 4. Whether or not the generated X-ray dose can be increased is determined by whether or not the voltage of the target 11 can be increased. If it is determined that the voltage can be increased, the voltage is increased by the control of the X-ray controller 21 in step 5. This increases the X-ray dose.
[0057]
On the other hand, when it is determined in step 4 that the X-ray dose generated by the target 11 cannot be increased by the control of the X-ray controller 21, the process proceeds to step 6, and in step 6, the collision position of the electrons 45 against the target 11 deteriorates. If it is determined that the X-ray dose cannot be increased unless the collision position is moved, the process proceeds to step 7. In step 7, the electrostatic field by the electrostatic deflection electrodes 8c and 8d is controlled by the control of the deflection electrode control circuit 22 to As shown in FIG. 3, the beam 45 is deflected to one side in the third direction C (one side in the right direction or left direction in the drawing). As the deflection amount, the deflection amount stored in advance in the ROM 26 is used. Thereby, the collision position of the electron beam 45 with respect to the target surface 11a also moves to one side in the third direction C, and the electron beam 45 collides with the non-collision position. In this deflection, since the collision position of the electron beam 45 with respect to the target surface 11a is only moved to one side in the third direction C and not in the first direction A, the X-line length does not change, and therefore the magnification changes. There is no.
[0058]
In this way, the collision position of the electron beam 45 with respect to the target surface 11a is moved to one side in the third direction C. However, the irradiation position of the X-ray 50 to the sample 1 is also moved to one side in the third direction C. In step 8, the sample manipulator 3 is driven to move the sample 1 to one side in the third direction C so that the same position of the sample 1 is irradiated. Further, since the same position of the sample 1 is no longer imaged by the X-ray camera 4 in this state, in step 9, the X-ray camera is driven so that the same position of the sample 1 is imaged by driving the manipulator 5 for the X-ray camera. 4 is moved to one side in the third direction. The amount of movement of the sample 1 by the sample manipulator 3 and the amount of movement of the X-ray camera 4 by the X-ray camera manipulator 5 correspond to the amount of deflection of the electron beam 45 by the electrostatic deflection electrodes 8c and 8d in advance. Is stored in the data table.
[0059]
Thus, in this embodiment, when the deterioration of the target 11 is determined by the target deterioration determination means 7a of the controller 7, the controller 7 controls the electrostatic deflection electrodes 8c and 8d, and the electrostatic deflection electrodes 8c, 8c, 8d further deflects the electron beam 45 toward the target 11 in the third direction C, and the collision position of the electron beam 45 with respect to the target 11 is moved from the deteriorated position in the third direction C. In this movement, the X-line length is increased. Since it does not change, the display 6a can obtain a clear enlarged image or reduced image of the sample 1 at the same magnification. At this time, the sample manipulator 3 is controlled by the controller 7, and the sample manipulator 3 further moves the sample 1 in the third direction C according to the amount corresponding to the deflection of the electron beam 45 in the third direction C. Therefore, the same position of the sample 1 can be irradiated with the X-ray 50 and the X-ray camera manipulator 5 is also controlled. The X-ray camera 4 causes the X-ray camera 4 to Since it is further moved in the third direction C according to the amount corresponding to the deflection in the three directions C, a clear enlarged image or reduced image of the same position of the sample 1 can be obtained at the same magnification on the display 6a.
[0060]
FIG. 7 is a longitudinal sectional view showing the main part of the X-ray inspection apparatus according to the second embodiment, and FIG. 8 is a perspective view showing the main part of FIG.
[0061]
The X-ray inspection apparatus of the second embodiment is different from that of the first embodiment in that the electrostatic deflection electrode 8 attached to the X-ray tube 2 is replaced with an electromagnetic deflection coil 18.
[0062]
As shown in FIG. 8, the electromagnetic deflection coil 18 is formed by dividing a ring arranged to allow the passage of the electron beam 45 into four equal parts and winding the coil around each ring. The electromagnetic coils 18a and 18b formed are opposed to each other in the first direction A with the electron beam 45 therebetween, and the other two pairs of electromagnetic coils 18c and 18d are opposed to the third direction C through the electron beam 45. Be placed. Similarly to the case of the electrostatic deflection electrode 8, the electromagnetic deflection coil 18 comprising these also deflects the electron beam 45 in the first direction A when the magnetic field by the electromagnetic coils 18 a and 18 b is controlled by the deflection electrode control circuit 22. When the magnetic field by the electromagnetic coils 18c and 18d is controlled, the electron beam 45 is deflected in the third direction C. Further, the electron beam 45 goes straight when not energized.
[0063]
In other words, since the electron beam 45 is deflected by the electrostatic field is changed to deflect the electron beam 45 by the magnetic field, the same effect as in the first embodiment can be obtained. Needless to say.
[0064]
In addition, since the electromagnetic deflection coil 18 is disposed outside the X-ray tube 2, the mounting adjustment of the electromagnetic deflection coil 18 is facilitated, and the manufacturing cost can be reduced.
[0065]
Although the present invention has been specifically described based on the embodiment, the present invention is not limited to the embodiment. For example, in the embodiment, an enlarged image or a reduced image of the same position of the sample 1 is used. The X-ray camera 4 is moved together with the sample 1 so that the deflection amount when deflecting the electron beam 45 in the first direction at the time of enlargement or reduction is small, or the target deterioration is determined by determining the target deterioration. When the amount of deflection when deflecting the electron beam 45 in three directions is small and the previous image is almost captured by the X-ray camera 4, the inspection does not deviate from the field of view of the X-ray camera 4 If the X-ray camera 4 is moved, an enlarged or reduced image including the same position of the sample 1 may be obtained. In this case, since vibration caused by the movement of the X-ray camera 4 is eliminated, a more preferable sample image with reduced blur can be obtained. Whether or not to move the X-ray camera 4 is determined by the controller 7 with reference to a data table in which whether or not to move in advance is stored in the ROM 26 according to the deflection amount of the electron beam 45. .
[0066]
In the above-described embodiment, the deterioration of the target 11 is determined based on the brightness of the sample image. For example, the target 11 is determined by a measuring device (proportional counter, Si photodiode, etc.) that detects the X-ray dose. Also good.
[0067]
Furthermore, in the above embodiment, the X-ray tube is the microfocus X-ray tube 2, but any other X-ray tube may be used as long as it has a reflective target 11.
[0068]
【The invention's effect】
An X-ray inspection apparatus according to the present invention generates X-rays by causing an electron beam to collide with a target in an X-ray source, emits the X-rays through the X-ray emission window, and passes through the X-ray emission window. While irradiating the sample held by the sample holding / moving means with the emitted X-ray and imaging the X-ray transmitted through the sample with an X-ray imaging device, the X-ray inspection on the sample can be performed, The controller controls the electron beam deflecting means, and the electron beam deflecting means deflects the electron beam directed toward the target in a first direction in contact with and away from the X-ray emission window in a plane including the electron beam, By moving the collision position of the electron beam with respect to the target in the first direction and changing the X-line length between the collision position and the sample and the X-ray imaging apparatus, an enlarged image or a reduced image of the sample is output as the output of the X-ray imaging apparatus. An image can be obtained, and the sample holding / moving means is controlled by the controller, and the sample holding / moving means causes the sample to move in the X-ray moving direction when the electron beam is deflected in the first direction. An enlarged image including the same position of the sample as an output of the X-ray imaging device, moving in the direction according to the amount corresponding to the deflection of the electron beam in the first direction, enabling the same position of the sample to be irradiated with X-rays Since it is configured to make it possible to obtain a reduced image, it is possible to provide an X-ray inspection apparatus capable of enlarging or reducing the sample image with a new configuration different from the conventional one.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an X-ray inspection apparatus according to a first embodiment.
2 is a longitudinal sectional view showing a microfocus X-ray tube including the electrostatic deflection electrode of FIG. 1. FIG.
3 is a perspective view showing a main part of a microfocus X-ray tube including the electrostatic deflection electrode of FIG. 2. FIG.
FIG. 4 is a flowchart showing a processing procedure when an enlarged or reduced image of a sample is obtained by an electrostatic deflection electrode.
FIG. 5 is a flowchart showing a processing procedure when an enlarged or reduced image of a sample is obtained by driving a manipulator.
FIG. 6 is a flowchart showing a processing procedure when the X-ray dose is increased.
FIG. 7 is a longitudinal sectional view showing a microfocus X-ray tube including an electromagnetic deflection coil of an X-ray inspection apparatus according to a second embodiment.
8 is a perspective view showing a main part of a microfocus X-ray tube including the electromagnetic deflection coil of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Sample, 2 ... Micro focus X-ray tube (X-ray source), 3 ... Sample manipulator (sample holding movement means), 4 ... X-ray camera (X-ray imaging device), 5 ... X-ray camera manipulator (X (Line imaging device moving means), 6 ... monitor device, 6a ... display, 7 ... controller (CPU), 7a ... target deterioration determining means, 8 ... electrostatic deflection electrode (electron beam deflection means), 9a ... X-ray exit window, DESCRIPTION OF SYMBOLS 11 ... Target, 11a ... Target surface, 18 ... Electromagnetic deflection coil (electron beam deflecting means), 45 ... Electron beam, 50 ... X-ray, A ... 1st direction, B ... 2nd direction, C ... 3rd direction.

Claims (7)

A target formed obliquely with respect to each of the incident electron beam and the X-ray exit window is generated, and the electron beam collides with the target to generate X-rays. An X-ray source exiting through
Electron beam deflecting means capable of deflecting the electron beam directed to the target in a first direction at least in contact with and away from the X-ray exit window in a plane including the electron beam;
A specimen that is seen through by X-rays emitted through the X-ray emission window is held, and the specimen is at least the moving direction of the X-rays when the electron beam is deflected in the first direction. A sample holding / moving means capable of moving in the second direction;
An X-ray imaging device for imaging X-rays transmitted through the sample;
The electron beam deflecting unit is controlled to deflect the electron beam in the first direction, and the sample holding / moving unit is controlled to control the electron beam according to an amount corresponding to the deflection of the electron beam in the first direction. A controller for moving the sample in the second direction;
An X-ray inspection apparatus comprising: An X-ray imaging apparatus moving means that enables the X-ray imaging apparatus to move at least in the second direction;
The controller controls the sample holding / moving means and the X-ray imaging apparatus moving means, respectively, and controls the sample and the X-ray imaging apparatus according to the amount corresponding to the deflection of the electron beam in the first direction. The X-ray inspection apparatus according to claim 1, wherein the X-ray inspection apparatus is moved in each of the second directions. The electron beam deflecting means can further deflect the electron beam in a third direction orthogonal to the first direction;
The sample holding / moving means is capable of further moving the sample in the third direction which is the moving direction of the X-ray when the electron beam is deflected in the third direction,
The controller includes deterioration determining means for determining deterioration of the target. When the deterioration of the target is determined, the controller controls the electron beam deflecting means to deflect the electron beam in the third direction and to hold the sample. 3. The X-ray inspection apparatus according to claim 2, wherein the sample is moved in the third direction according to an amount corresponding to the deflection of the electron beam in the third direction by controlling a moving means. The X-ray imaging device moving means can further move the X-ray imaging device in the third direction,
When the controller determines the deterioration of the target, the controller controls the electron beam deflecting unit to deflect the electron beam in the third direction, and controls the sample holding / moving unit and the X-ray imaging device moving unit, respectively. 4. The X-ray inspection according to claim 3, wherein the specimen and the X-ray imaging device are respectively moved in the third direction according to an amount corresponding to the deflection of the electron beam in the third direction. apparatus. The X-ray inspection apparatus according to claim 3, wherein the controller determines the deterioration of the target based on a darkness of a sample image as an output of the X-ray imaging apparatus or a value of an X-ray detector. 6. The X-ray inspection apparatus according to claim 1, wherein the electron beam deflection means is an electrostatic deflection electrode. The X-ray inspection apparatus according to claim 1, wherein the electron beam deflection unit is an electromagnetic deflection coil.

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