X-ray inspection device and x-ray inspection system

Abstract

Provided are an X-ray inspection device and an X-ray inspection system that make it possible, with a single device, to observe a sample by using a detector suitable for various applications. The present invention comprises: an X-ray source that projects parallel X-rays onto a plate-shaped sample; a sample stage on which the sample is held; a plurality of detectors 286-288 that each have a different resolution and that detect a projection image of the X-rays that were transmitted through the sample; a switching mechanism 281 for switching the detectors 286-288; and adjustment mechanisms 283 that adjust the disposition of the detectors 286-288, independently for each of the detectors 286-288. Adjustment mechanisms 284a-284d make it possible to move each of the detectors 286-288 in a direction of approaching or separating from the sample, along the optical axis of the irradiated X-rays.

Description

X-ray inspection equipment and X-ray inspection system 【0001】 The present invention relates to an X-ray inspection apparatus and an X-ray inspection system used for inspecting samples and acquiring X-ray projection images. 【0002】 Conventionally, in semiconductor manufacturing processes, devices that use X-rays to inspect the internal structure of samples such as wafers are known. Such devices include those that detect diffracted X-rays, such as topography and rocking curve measurements, and those that utilize projection images, such as CT measurements and laminography measurements. 【0003】 For example, Patent Document 1 discloses an integrated X-ray single crystal evaluation apparatus that performs topography measurement and rocking curve measurement in a single device. In the apparatus described in Patent Document 1, the entire detection unit is moved on a guide rod in a direction perpendicular to the incident diffracted X-rays, thereby switching to a detector suitable for each measurement. 【0004】 Patent No. 4495631 【0005】 However, the specifications required for the equipment differ significantly between diffraction and projection methods. For example, diffraction equipment requires high 2θ positional accuracy to obtain information about the crystal structure, and a dynamic range that can accurately measure scattering signals from minute regions is required. On the other hand, projection equipment requires a wide field of view and high spatial resolution to observe pattern defects, foreign matter, and structural shapes. 【0006】 This invention has been made in view of these circumstances, and aims to provide an X-ray inspection apparatus and X-ray inspection system that can observe a sample using a detector suitable for each application, with a single device that can handle both low-magnification observation of a wide area and high-magnification observation of a narrow area. 【0007】(1) To achieve the above objective, the X-ray inspection apparatus of the present invention comprises an X-ray source that irradiates a flat plate-shaped sample with parallel X-rays, a sample stage that holds the sample, a plurality of detectors each having a different resolution and detecting a projection image of the X-rays that have passed through the sample, a switching mechanism for switching between the detectors, and an adjustment mechanism for independently adjusting the arrangement of each of the detectors, wherein the adjustment mechanism is characterized in that it makes each of the detectors movable in a direction toward or away from the sample along the optical axis of the irradiated X-rays. 【0008】 (2) The X-ray inspection apparatus described in (1) above is further characterized by comprising an optical microscope used for setting the X-ray irradiation position on the surface of the sample and for aligning the optical axis of the detector reference position with the irradiated X-rays. 【0009】 (3) The X-ray inspection apparatus described in (1) or (2) above is characterized in that the detector includes a detector for identifying the location of a defect in the sample and a detector for observing the state of the defect. 【0010】 (4) In addition, in the X-ray inspection apparatus described in any of (1) to (3) above, the sample stage is capable of rotating the sample around a sample axis perpendicular to the surface of the sample, and in imaging measurement, the optical axis of the irradiated X-rays is aligned with the sample axis to acquire the projection image, and in laminography measurement, the intersection point of the optical axis of the irradiated X-rays and the sample axis is aligned with the observation position of the sample, and the optical axis of the irradiated X-rays is tilted from the sample axis, and multiple projection images are acquired while rotating the sample. 【0011】 (5) The X-ray inspection apparatus described in (4) above is characterized in that the detector includes a detector used only for imaging measurement and a detector used for both imaging and laminography measurement. 【0012】(6) In addition, in the X-ray inspection apparatus described in any of (1) to (5) above, the plurality of detectors are arranged so that the central axes of the detection surfaces are aligned in a line, and the switching mechanism switches the detectors by moving the entire plurality of detectors along the direction of the alignment. 【0013】 (7) The X-ray inspection system of the present invention also comprises an X-ray inspection apparatus as described in any of (1) to (6) above, and a control device for controlling the X-ray inspection apparatus, wherein the control device adjusts the arrangement of the switched detectors by pattern recognition of the projection image. 【0014】 This is a diagram showing the sample to be inspected. This is a diagram showing the package to be inspected. This is a schematic diagram showing the arrangement of the X-ray source and detector for central imaging. This is a schematic diagram showing the arrangement of the X-ray source and detector for edge imaging. This is a schematic diagram showing the arrangement of the X-ray source and detector for edge laminography. This is a schematic diagram showing the X-ray inspection system of the present invention. This is a block diagram showing the X-ray inspection system of the present invention. This is a cross-sectional view showing the X-ray inspection apparatus. This is a perspective view showing the X-ray inspection apparatus. This is a perspective view showing the intermediate transport system. This is a perspective view showing the main unit. This is an exploded view showing the main unit. This is a side cross-sectional view showing the incident unit. This is a perspective view showing the incident unit. This is a perspective view showing the incident unit. This is a perspective view showing the sample stage. This is an exploded perspective view showing the sample stage. This is a perspective cross-sectional view showing a part of the main unit. This is an exploded perspective view of the light receiving unit. This is a perspective view showing the detector and its rotation axis. This is a plan view showing the sample transport process. This is a side view of the main unit when the light receiving unit is at 0°. This is a side view of the main unit when the light receiving unit is at 50°. 【0015】 Next, embodiments of the present invention will be described with reference to the drawings. To facilitate understanding of the description, the same reference numerals are used for identical components in each drawing, and redundant descriptions are omitted. 【0016】[Items to be inspected] The samples to be inspected by the X-ray inspection device are, for example, substrates on which wiring etc. is formed on a wafer. The samples are mainly flat structures made of high-purity single-crystal silicon, and are formed, for example, as discs with a diameter of 300 mm and a thickness of several hundred μm. Samples that have been treated by etching, film deposition, etc. are inspected. Figures 1A and 1B show the sample and package to be inspected, respectively. 【0017】 After the substrate is diced into individual chips, each chip is sealed for electrical connection and physical protection, thus forming a package. The package has a fine structure. Inside the package are TSVs (Through-Silicon Vias) that transmit electrical signals in the vertical direction within the chip, micro-bumps that connect chips to each other, and C4 bumps that connect the chips to the package substrate. An insulating resin called underfill is filled between the chips and the substrate, and solder balls are provided as external connection terminals for the package substrate. 【0018】 In semiconductor manufacturing processes, inspections are conducted to check for defects in the internal structure of such packages, including voids, cracks, and metal filling defects in TSVs, voids, delamination, unbonded areas, and foreign matter in bonding and underfill, and voids, bridges, misalignment, and cracks in solder joints. Among such inspection processes, X-ray inspection systems are particularly effective in confirming the presence, location, and condition of defects in the internal structure at the substrate stage. Samples may include glass and resin substrates other than silicon substrates. Furthermore, wafers and glass that have been individually packaged may also be subject to inspection. 【0019】[X-ray Inspection System] The X-ray inspection system enables imaging and laminography by irradiating X-rays from an X-ray source according to user control and detecting the X-rays transmitted through a sample (a disk-shaped substrate) with a detector. FIGS. 2A to 2C are schematic views showing the arrangements of the X-ray source and the detector for imaging and laminography at the central part and the end part, respectively. The X-rays are irradiated from the vertically downward side to the upward side. The X-axis, Y-axis, and Z-axis represented in FIGS. 2A to 2C are the sample coordinate system (or the coordinate system of the sample stage). 【0020】 In the example of the measurement shown in FIG. 2A, the X-rays irradiated from the X-ray source C1 pass through the sample W1, and a transmission image is acquired by the detector D1. As shown in FIG. 2B, the sample W1 is installed so as to be movable on the X-axis and Y-axis of the sample stage, respectively. In the example shown in FIG. 2C, the X-ray source C1 and the detector D1 are inclined by θ from the axis perpendicular to the surface of the sample W1, and the measurement is performed by rotating the sample W1. The projection image is a representation of the intensity distribution of the X-rays transmitted through the sample as data acquired from a predetermined angle and includes a so-called transmission image. 【0021】 FIG. 3A is a schematic view showing the X-ray inspection system 50. The X-ray inspection system 50 includes a control device 100 and an X-ray inspection device 200. The control device 100 and the X-ray inspection device 200 are connected by wire or wirelessly so that information can be transmitted. The control device 100 transmits a control instruction to the X-ray inspection device 200 according to a user operation. The X-ray inspection device 200 operates according to the control instruction and performs inspection of the sample. 【0022】 FIG. 3B is a block diagram functionally showing the X-ray inspection system 50. The control device 100 is composed of a computer 110, an input device 180, and an output device 190, receives user input, controls the X-ray inspection device 200 to acquire a projection image, and performs its processing and display. The functions of the control device 100 are mainly realized by the computer 110. The computer 110 includes an input / output control unit 111, a setting storage unit 113, a detector switching unit 114, a detector adjustment unit 115, an imaging execution unit 116, a data storage unit 117, and a reconstruction unit 118. Each unit can transmit and receive information through the control bus L. 【0023】 The control device 100 is composed of a computer in which a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a memory are connected to a bus. The control device 100 may be a PC terminal or a server on the cloud. Also, not only the entire device but also some devices or some functions within the device may be provided on the cloud. 【0024】 The input / output control unit 111 receives inputs from the input device 180 and controls outputs to the output device 190. The setting storage unit 113 stores setting information such as the arrangement of detectors. The detector switching unit 114 transmits a detector switching instruction to the X-ray inspection device 200 and controls the switching of the detector. After receiving a designation of a projection image or a three-dimensional image to be measured from the user, it is preferable to automatically select a detector to be used based on the designation. Note that selection of a detector by the user himself / herself is also acceptable as necessary. 【0025】 The detector adjustment unit 115 adjusts the arrangement of the detector before imaging. When using the position information of the sample and the detector, the relative position between the sample and the detector may be specified, and the arrangement of the detector may be adjusted based on that. The imaging execution unit 116 transmits a control instruction to the X-ray inspection device 200 and images the installed sample. The data storage unit 117 stores the data of the acquired projection images. The reconstruction unit 118 reconstructs a three-dimensional image using the data of the stored projection images. 【0026】 [X-ray Inspection Device] The X-ray inspection device 200 performs measurement by irradiating a sample with X-rays to acquire a projection image. FIGS. 4A and 4B are a cross-sectional view and a perspective view showing the X-ray inspection device 200, respectively. As shown in FIGS. 4A and 4B, the X-ray inspection device 200 includes a frame upper part 210, a frame lower part 215, an electrical equipment box 220, an EFEM 230, an intermediate conveyance system 240, a main unit 250, an incident unit 260, a sample stage 270, and a light receiving unit 280. 【0027】The upper part of the frame 210 has a skeleton formed along the edges of the cube surrounding the main unit 250, and its vertically downward open end is connected to the lower part of the frame 215. The lower part of the frame 215 is formed in a plate shape and supports the main unit 250. Although not shown, the main unit 250 is covered with a panel that shields against X-rays. The electrical box 220 contains a PLC, power control equipment, etc. inside its cover. The EFEM 230 (Equipment Front End Module) is a relay device that connects the main unit 250 to the transport system in the factory. The intermediate transport system 240 has a robotic arm and transports the sample received from the EFEM 230 to the sample stage 270. The main unit 250 is equipped with an ingress unit 260, a sample stage 270, and a light receiving unit 280, and performs sample placement, X-ray irradiation, and detection. 【0028】 Figure 5 is a perspective view showing the intermediate transport system 240. The intermediate transport system 240 comprises a support base 245 and a robot arm 247. The support base 245 is cylindrical with a diameter equal to the substrate diameter and supports the robot arm 247. The robot arm 247 holds the sample W1 and transports it to the sample stage 270. In the example of the intermediate transport system 240 shown in Figure 5, the robot arm 247 holds the sample W1. 【0029】 The main unit 250 has the main functions of the device, such as holding the sample W1, irradiating with X-rays, and detecting the projected image. Figures 6A and 6B are perspective and exploded views, respectively, of the main unit 250. As shown in Figures 6A and 6B, the main unit 250 is supported by the lower part of the frame 215 and surrounded by the upper part of the frame 210, and includes an internal frame 251, an incident unit 260, a sample stage 270, a light receiving unit 280, an arm 290, and a goniometer 295. 【0030】The internal frame 251 is formed as a grid-like box with a frame structure and an opening at the top vertically. The incident unit 260 is housed at the bottom of the internal frame 251 and irradiates the sample with parallel X-rays from directly below the sample. Parallel X-rays include X-rays that are irradiated at a nearly constant angle of incidence to the target and have convergence or divergence to an extent that does not affect the measurement or detection results. The periphery of the sample stage 270 is fixed to a frame that forms an opening in the internal frame 251. The sample stage 270 holds a disc-shaped sample and adjusts the arrangement of the sample. 【0031】 The light receiving unit 280 is mounted on the outer arm of the arm 290, which is positioned at the maximum rotation radius of the arm 290, and detects X-rays transmitted through the sample W1 from the vertically above the sample. The arm 290 is connected to the goniometer 295 and is controlled by the goniometer 295. The goniometer 295 is installed on the internal frame 251 so that its angle can be controlled around its rotation axis. This allows for the acquisition of a projected image at an angle inclined from the sample axis. 【0032】 [Injection Unit] The injection unit is a mechanism for irradiating X-rays from a predetermined angle. Figures 7A to 7C are side cross-sectional views and perspective views with different arrangements showing the injection unit 260, respectively. As shown in Figures 7A to 7C, the injection unit 260 consists of an injection unit base 261, a θ-axis R guide section 262, a θ-axis motor 263, and a Y １ Axis LM guide section 264, X １ Axis LM guide section 265, guide plate 266, Z １ It is equipped with an axial LM guide 267 and an X-ray source 268. The coordinate system of the incident unit 260 and the light receiving unit 280 is X １ Axis, Y １ Axis and Z １ Represented by axes. 【0033】 The injection unit base 261 is fixed to the bottom of the internal frame 251 and supports the entire injection unit 260. The θ-axis R guide section 262 is provided on the injection unit base 261 and has an arc-shaped rail for rotating the X-ray source 268 along the θ axis. From the viewpoint of stability of movement, it is preferable to have two rails (the same applies hereafter). 【0034】 The θ-axis motor 263 provides a driving force to rotate the X-ray source 268 about the θ-axis. Note that the θ-axis rotation direction of the X-ray source 268 coincides with the θ-axis rotation direction of the arm 290, and by the interlocking operation of both, a projection image at a predetermined θ angle can be obtained. The Y-axis of the sample stage 270 and the Y-axes of the incident unit 260 and the light receiving unit 280 are all equivalent to and common with this θ-axis. １ axes are all equivalent to and common with this θ-axis. 【0035】 Y １ axis LM guide portion 264 is provided on the θ-axis R guide portion 262. On the Y １ axis LM guide portion 264, a rail for moving the X-ray source 268 in the Y １ axis direction (θ-axis direction) is formed. The X １ axis LM guide portion 265 is provided on the Y １ axis LM guide portion 264. On the X １ axis LM guide portion 265, a rail for moving the X-ray source 268 in the X １ axis direction (a direction perpendicular to the Y １ axis and the Z １ axis) is formed. 【0036】 The guide plate 266 is provided on the X １ axis LM guide portion 265. On the guide plate 266, a Z １ axis LM guide 267 is formed as a rail for moving the X-ray source 268 in the Z １ axis direction (X-ray irradiation direction). The X-ray source 268 is connected to the guide plate 266 so as to be movable on the Z １ axis LM guide 267. The X-ray source 268 irradiates the sample W1 with parallel X-rays. 【0037】 [Sample Stage] The sample stage 270 holds the sample W1 and can position the sample W1 independently in the X-axis direction (a horizontal direction perpendicular to the Y-axis), the Y-axis direction (θ-axis direction), the Z-axis direction (a direction perpendicular to the XY plane), and the rotation direction about the central axis (sample axis) perpendicular to the sample surface. The sample stage 270 can also rotate the sample W1 about the sample axis perpendicular to the surface of the sample W1 during X-ray irradiation. 【0038】 Figure 8 is a perspective view showing the sample stage 270. Figure 9 is an exploded perspective view showing the sample stage 270. The sample stage 270 comprises a stage base 271, a θ rotation base 272, an X-axis base 273, a Y-axis base 274, and a Z-axis base 275. 【0039】 The stage base 271 comprises a main body 271a and a θ-rotation motor 272a, and is fixed to the edge portion of the upper end opening of the internal frame 251. The stage base 271 supports the θ-rotation base 272 so that it can rotate by a θ. The main body 271a is formed as a plate with a circular hole in the center, and the θ-rotation motor 272a transmits rotational driving force to the θ-rotation base 272. 【0040】 The θ-rotating base 272 is mounted on the stage base 271 via bearings and can rotate more than 360° around the central axis of the sample W1 by the driving force of the θ-rotating motor 272a. The X-axis base 273 is mounted on the θ-rotating base 272 and can be positioned in the X-axis direction within a range greater than or equal to the diameter of the sample W1 (e.g., ±160 mm). The Y-axis base 274 is mounted on the X-axis base 273 and can be positioned in the Y-axis direction within a range greater than or equal to the diameter of the sample W1 (e.g., ±160 mm). The movement mechanisms in the X-axis and Y-axis directions are preferably controlled by a linear encoder using the sliding movement driven by a motor with an LM guide. 【0041】 The Z-axis base 275 is mounted on the Y-axis base 274 and can be positioned in the Z-axis direction within a range greater than or equal to the thickness of the sample W1 (for example, ±3 mm). The moving mechanism preferably transmits the driving force of the motor to the Z-axis base 275 via a helical gear or the like, enabling fine adjustments by sliding movement. 【0042】The Z-axis base 275 is equipped with four chucks 277. The chucks 277 are fixing devices that secure the peripheral edge of the sample W1 under vacuum. It is preferable to have three or more chucks 277 from the viewpoint of stably holding the sample W1. The θ-rotating base 272, X-axis base 273, Y-axis base 274, and Z-axis base 275 all have a hole in the center and are designed so that X-rays do not penetrate anything other than the sample. In addition, each is provided with an axial movement mechanism. 【0043】 [Light Receiving Unit] The light receiving unit 280 is equipped with multiple detectors, and one of the selected detectors detects the X-rays transmitted through the sample W1. Figure 10 is a perspective cross-sectional view showing a part of the main unit 250 (cross-sectional view according to the cross-section CS1 shown in Figure 6). Figure 11 is a perspective exploded view of the light receiving unit 280. 【0044】 The light receiving unit 280 includes a switching mechanism 281, a light receiving unit base 282, and X １ Axis adjustment mechanism 283a to 283d, Z １ It is equipped with axis adjustment mechanisms 284a to 284d, an optical microscope 285, a topographic detector 286, a first detector 287, and a second detector 288. 【0045】 The switching mechanism 281 comprises a rod 281a and a main body 281b. The rod 281a has a longitudinal direction of Y １ It is fixed to the outer arm of the arm 290 along the axial direction (θ-axis direction). The main body 281b is positioned along the rod 281a and is mounted on the rod 281a so as to be movable. Multiple detectors 286 to 288 are arranged so that the central axis of the detection surface is aligned in a line along a specific direction. 【0046】 The switching mechanism 281 moves the main body 281b along the rod 281a to position the optical microscope 285 or each detector 286-288 on the X-ray optical axis. This allows the user to select any detector or optical microscope according to the observation purpose and switch between them precisely, easily, and quickly. The switching mechanism 281 controls the Y of the optical microscope 285 and each detector 286-288. １ It also functions as an axis adjustment mechanism. 【0047】 The light-receiving unit base 282 is fixed to the main body 281b of the switching mechanism 281, and the light-receiving unit base 282 determines the reference position of the detectors 286 to 288. The reference position is specified by the position (X, Y, Z) and a predetermined orientation in the sample coordinate system, and is used as a reference when adjusting each detector 286 to 288. By setting the reference position, the sample can always be measured with a spatial resolution and field of view that has a certain level of accuracy or higher. 【0048】 Optical microscope 285 and X-rays of each detector 286-288 １ The axis adjustment mechanisms 283a to 283d are slidably mounted on the light receiving unit base 282. １ The axis adjustment mechanisms 283a to 283d control the X of the optical microscope 285 and each detector 286 to 288. １ The position on the axis can be adjusted independently. １ The axis direction is Y １ Axis and Z １ It is perpendicular to the axis. 【0049】 Z １ The axis adjustment mechanisms 284a to 284d are each X １ It is slidably mounted on the axis adjustment mechanism 283a to 283d. １ The axis adjustment mechanisms 284a to 284d are Z-axis adjustment mechanisms for the optical microscope 285 and each detector 286 to 288. １ The position on the axis can be adjusted independently. １ The axis represents the direction of X-ray irradiation. 【0050】 Z １The axis adjustment mechanisms 284a to 284d allow each detector to be moved to a position closer to or further away from the sample along the optical axis of the irradiated X-ray. This allows a single device to observe a sample with a detector suitable for each application, whether it is necessary to observe a wide area at low magnification or a narrow area at high magnification. In particular, when observing the sample W1 at high magnification, the distance between detectors 286 to 288 and the sample W1 can be set to 1 mm or less when the incident angle of the X-rays is perpendicular to the sample surface. In the case of oblique incidence to the sample surface, the distance is set further to avoid interference between the camera and the substrate. For example, when the incident angle is 10°, the distance is 8 mm or less. This prevents distortion at the edges of the projected image and allows for a large effective field of view. 【0051】 The optical microscope 285 determines the X-ray irradiation position on the sample surface and identifies the observation position. As a result, the optical microscope 285 is also used for aligning the optical axis of the X-ray irradiation direction by aligning the optical axis of the optical microscope with the direction of X-ray irradiation. Since the optical axis of the irradiated X-rays can be aligned with the reference position of each detector 286-288, the arrangement of each detector 286-288 can be easily adjusted. 【0052】 Each detector 286-288 has a different field of view (FOV) and resolution, and each detects a projection image of X-rays transmitted through the sample W1. In this embodiment, for example, a configuration can be adopted in which three different cameras are provided as detectors 286-288. 【0053】 The topographic detector 286, which has the widest field of view (FOV), detects a projection image of a portion of the sample W1. The obtained projection image is used to align the observation position of the sample W1 and to check for defects. In this case, the pixel size is 3.8 μm and the FOV is 36 × 24 mm. The first detector 287 has a wide field of view and can be used to identify the location of defects in the internal structure. For example, the first detector 287 also has an internal lens, acting as an X-ray camera with intermediate resolution, with a resolution of 1.5 μm and an FOV of 9.4 × 6.3 mm. 【0054】Then, the location of the defect identified by the first detector 287 can be magnified using the second detector 288, which has high resolution, to observe the state of the defect. For example, the second detector 288, as the X-ray camera with the highest resolution, has a lens inside to increase the magnification of the image and obtain high resolution. Its pixel size, which represents its resolution, is 0.2 μm or less, and its FOV is 1.7 × 1.1 mm. 【0055】 In this manner, it is desirable for each detector 286 to 288 to perform a role in stages. In this case, when switching, the detectors are basically aligned using known calibration data. Furthermore, positional information may be identified by pattern recognition of the projection image captured by the detector before switching, and the arrangement of the detector after switching may be adjusted using the obtained positional information. The process of identifying positional information from pattern recognition can be performed by the control device 100. 【0056】 Furthermore, as described above, after identifying the defect location using the first detector 287 in imaging measurement, imaging may be performed using the second detector 288 in laminography measurement. In this way, it is possible to switch between detectors depending on the type of measurement and quickly switch between the two measurements for efficient inspection. In this manner, it is also possible to quantitatively calculate what percentage of the void volume in a given area is occupied by the projection image obtained by the second detector 288. 【0057】 In this embodiment, for example, among the detectors described above, the topography detector 286 is used only for imaging measurements. On the other hand, at least one of the first detector 287 and the second detector 288 is used for both imaging and laminography measurements. In this way, it is also possible to classify detectors by application. A detector with a high frame rate can also be used for laminography measurements. Note that the above embodiment is just one example, and the performance and division of roles of each detector are not limited to this example. 【0058】 As described above, X of the optical microscope 285 and each of the detectors 286-288 １ Axis, Y １ Axis and Z １The position on the axis is precisely adjusted. Furthermore, the angular position around each axis is also precisely adjusted. Figure 12 is a perspective view showing the second detector 288 and its rotation axis. 【0059】 As shown in Figure 12, the second detector 288 controls X １ Around the axis and Z １ Precise angle adjustment around the axis is possible. １ The axial adjustment can be made by adjusting the angle of the arm 290 using a goniometer and by adjusting the X-ray source 268, at least one of the two. The optical microscope 285 and each of the detectors 286-287 are also X-ray sources, similar to the second detector 288. １ Around the axis, Y １ Around the axis and Z １ Precise angle adjustment around the axis is possible. In this way, the adjustment mechanisms for the optical microscope 285 and each of the detectors 286-287 can be independently and precisely adjusted in their respective positions. 【0060】 [System Operation] An example of the operation of the X-ray inspection system 50 configured as described above will be explained. First, the sample is placed on the sample stage 270 in the X-ray inspection apparatus 200. Figure 13 is a plan view showing the sample transport process. Figures 14A and 14B are side views of the main unit when the light receiving unit is at 0° and 50°, respectively. 【0061】 As shown in Figure 13, the sample to be inspected (a disc-shaped substrate) W1 is picked up from the LP (load port) and placed on the aligner (operation L1), the notch angle of the sample is adjusted on the aligner (operation L2), and then placed on the intermediate stage (operation L3). Then, the robot arm 247 of the intermediate transport system 240 grasps the sample W1 and places it on the sample stage 270 (operation L4). 【0062】 During the examination, for example, imaging conditions are selected, and first, a projection image is acquired for a specific area of ​​the sample W1 in a wide field of view using the imaging mode. At that time, the wide-field first detector 287 is selected, and the switching mechanism 281 switches the currently used detector to the first detector 287. Based on adjustment data, the adjustment mechanisms (281), 283c, and 284c adjust the position of the first detector 287. 【0063】If no defects can be identified in the internal structure through wide-field observation, the position of the sample stage 270 is adjusted to acquire a projection image for a different area. If a defect is found, a high-magnification projection image is acquired for the region of interest containing the defect. In this case, the second detector 288, which offers high magnification and high resolution, is selected, and the switching mechanism 281 switches the currently used detector to the second detector 288. This switching operation may be performed immediately after the discovery of a defect, or it may be performed separately offline. 【0064】 Then, based on the adjustment data, the adjustment mechanisms (281), 283d, and 284d adjust the position of the second detector 288, and the second detector 288 acquires a projection image. Furthermore, if the three-dimensional structure of the region of interest needs to be confirmed, the control device 100 instructs laminography measurement. 【0065】 The X-ray inspection apparatus 200 adjusts the positions of the incident unit 260 and the arm 290 from, for example, θ = 0° (Figure 14A) to θ = 50° (Figure 14B), and acquires multiple projection images while rotating the sample stage 270. The control device 100 reconstructs a three-dimensional image from the obtained projection images. The angle θ of the X-ray irradiation direction can be finely adjusted to a specific angle between 0 and 50°. 【0066】 As described above, in imaging measurements, the X-ray inspection device 200 aligns the optical axis of the irradiated X-rays with the sample axis to acquire a projection image. In laminography measurements, while aligning the intersection point of the optical axis of the irradiated X-rays and the sample axis with the observation position of the sample, the optical axis of the irradiated X-rays is tilted from the sample axis, and multiple projection images are acquired while rotating the sample. This allows imaging and laminography measurements to be performed with a single device. 【0067】 After inspection, sample W1 is returned to its original process. Specifically, sample W1 is placed on the intermediate stage (operation U1), the robot arm 247 of the intermediate transport system 240 grasps sample W1 (operation U2), and sample W1 is returned to the LP (load port) (operation U3), thus completing the series of inspection processes. 【0068】50 X-ray inspection system 100 Control device 110 Computer 111 Input / output control unit 113 Setting storage unit 114 Detector switching unit 115 Detector adjustment unit 116 Imaging execution unit 117 Data storage unit 118 Reconstruction unit 180 Input device 190 Output device 200 X-ray inspection device 210 Upper part of frame 215 Lower part of frame 220 Electrical box 240 Intermediate transport system 245 Support base 247 Robot arm 250 Main unit 251 Internal frame 260 Incidence unit 261 Incidence unit base 262 θ-axis R guide unit 263 θ-axis motor 264 Y １ Axis LM guide section 265 X １ LM shaft guide section 266 Guide plate 267 Z １ 268 LM axis guide 270 X-ray source 270 Sample stage 271 Stage base 271a Main body 272 θ rotation base 272a θ rotation motor 273 X axis base 274 Y axis base 275 Z axis base 277 Chuck 280 Light receiving unit 281 Switching mechanism (Y １ Axis adjustment mechanism) 281a Rod 281b Main body 282 Light receiving unit base 283a-283d X １ Axis adjustment mechanism 284a-284d Z １ Axis adjustment mechanism 285 Optical microscope 286 Topographic detector 287 First detector 288 Second detector 290 Arm 295 Goniometer C1 X-ray source D1 Detector L Control bus W1 Sample θ Angle

Claims

An X-ray source that irradiates a flat plate-shaped sample with parallel X-rays, A sample stage for holding the aforementioned sample, Multiple detectors, each having a different resolution, for detecting the projected image of X-rays transmitted through the sample, A switching mechanism for switching the aforementioned detector, Each of the aforementioned detectors is provided with an adjustment mechanism for independently adjusting the arrangement of the detectors, The adjustment mechanism is characterized by making each of the detectors movable in a direction toward or away from the sample along the optical axis of the irradiated X-rays. 　 The X-ray inspection apparatus according to claim 1, further comprising an optical microscope used for setting the X-ray irradiation position on the surface of the sample and for aligning the optical axis between the reference position of the detector and the irradiated X-rays. 　 The X-ray inspection apparatus according to claim 1 or 2, characterized in that the detector includes a detector for identifying the location of a defect in the sample and a detector for observing the state of the defect. 　 The sample stage can rotate the sample around a sample axis perpendicular to the surface of the sample. In imaging measurements, the optical axis of the irradiated X-rays is aligned with the sample axis to acquire the projection image. In laminography measurements, the X-ray inspection apparatus according to claim 1 or 2 is characterized in that, while the intersection point of the optical axis of the irradiated X-rays and the sample axis coincides with the observation position of the sample, the optical axis of the irradiated X-rays is tilted from the sample axis, and the sample is rotated while acquiring a plurality of projection images. 　 The X-ray inspection apparatus according to claim 4, characterized in that the detector includes a detector used only for imaging measurements and a detector used for both imaging and laminography measurements. 　 The plurality of detectors are arranged so that the central axes of the detection surfaces are aligned in a line. The X-ray inspection apparatus according to claim 1 or 2, characterized in that the switching mechanism switches the detectors by moving the entire plurality of detectors along the direction of the arrangement. 　 An X-ray inspection apparatus according to claim 1 or claim 2, The system includes a control device for controlling the aforementioned X-ray inspection apparatus, The control device is characterized by adjusting the arrangement of the switched detectors by pattern recognition of the projected image.

Images