Charged particle beam apparatus and method for preparing and observing sample pieces

Abstract

Provided is a charged particle beam device that controls the orientation of a holder 6 capable of holding a plurality of carriers, and that is capable of transporting the holder independently of a wafer stage 21. The charged particle beam device comprises: a wafer stage 21 on which a wafer is placed and moved; a needle which holds a sample piece separated and removed from the wafer, and transports the sample piece to a plurality of carriers attached to the holder; and a sub-stage 22 which holds the holder, and moves independently of the wafer stage 21.

Description

Technical Field

[0001] The present disclosure relates to a charged particle beam apparatus for processing and observing a sample, and a method for producing and observing a sample piece.

Background Art

[0002] As the miniaturization of the structure of semiconductor devices, the increase in the density of circuit patterns, and the multi-layerization of wiring progress, for example, the importance of cross-sectional analysis of wafers using a transmission electron microscope (TEM) or a scanning transmission electron microscope (STEM) has been increasing for reliability improvement and the like.

[0003] In imaging, observation, measurement, analysis, evaluation, inspection, etc. of samples in the semiconductor manufacturing process, for example, thinning processing of a specified location on a wafer is performed by a focused ion beam (FIB) apparatus. By this thinning processing, a sample piece (also called a lamella, a thin film sample, etc.) in which the cross-sectional structure of the device is exposed is produced. The sample piece is transferred to a carrier, and the cross-sectional structure of the sample piece is observed by, for example, a TEM apparatus.

[0004] A micro-sampling method is known as a method for transferring a sample piece to a carrier. In the micro-sampling method, in a charged particle beam apparatus, a sample piece extracted from a sample with a microprobe is transferred to a carrier (TEM mesh). In order to change the posture of the carrier after the sample piece is transferred to the carrier, it is necessary to unload the carrier.

[0005] Patent Document 1 describes a charged particle beam apparatus capable of processing by FIB and observation by SEM (Scanning Electron Microscope). This charged particle beam apparatus comprises a sample holder for holding and fixing thin section samples, and a sample stage on which the sample holder is placed. The sample stage is capable of movement in the three axes of X, Y, and Z, tilting around an inclination axis perpendicular to the irradiation axis of the FIB, and rotation. The sample holder has a rotating stage that rotates around a holder shaft on a base placed on the sample stage, and a worm wheel housed in a recess formed in the rotating stage and rotating around a roller axis independently of the rotating stage. A carrier to which thin section samples can be directly attached is provided at the top of the worm wheel. This structure allows the charged particle beam apparatus of Patent Document 1 to change the orientation of the carrier without unloading the carrier. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2016-72089 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] However, the sample holder in Patent Document 1 can only hold one carrier, which limits the number of sample pieces that can be transferred to the carrier, resulting in low efficiency in observing the sample pieces. Furthermore, in the charged particle beam apparatus in Patent Document 1, the sample stage on which the wafer is placed and the sample holder are transported as a single integrated structure. Therefore, increasing the size of the sample stage makes transport difficult, while decreasing the size of the sample stage limits the size of wafers that can be placed on it. [Means for solving the problem]

[0008] A brief overview of some of the representative embodiments disclosed in this application is as follows:

[0009] A charged particle beam apparatus in one embodiment is a charged particle beam apparatus for creating a sample piece from a wafer using a charged particle beam, comprising: a charged particle beam tube for irradiating the charged particle beam; a wafer stage on which the wafer is placed and moved; a sample piece transfer mechanism for holding the sample piece separated and extracted from the wafer and transporting it to a plurality of carriers mounted on a sample piece holder; and a sample piece holder stage on which the sample piece holder is detachably mounted and which moves independently of the wafer stage.

[0010] In one embodiment, the method for preparing and observing a sample piece involves irradiating a wafer with an ion beam to process the sample piece so that the observation surface is the plane or cross-section of the wafer; attaching a sample piece transfer mechanism to the processed sample piece to extract and separate it from the wafer; mounting the sample piece on a carrier on a sample piece holder mounted on a sample piece holder stage that is tiltable and rotatable, so that the observation surface is parallel to the surface of the carrier; rotating the sample piece holder stage so that the observation surface of the sample piece can be observed with an electron beam; and rotating the sample piece holder stage so that the back surface of the observation surface of the sample piece can be observed with an electron beam.

[0011] In one embodiment, the method for preparing and observing a sample piece involves irradiating a wafer with an ion beam, processing the sample piece with the planar or cross-section of the wafer as the observation surface, attaching a sample piece transfer mechanism to the processed sample piece to extract and separate it from the wafer, mounting the sample piece on a carrier on a sample piece holder mounted on a sample piece holder stage that can tilt and rotate, tilting the sample piece holder stage so that the observation surface is parallel to the surface of the carrier, and then, with the observation surface or front The sample holder stage is rotated so that the back surface of the observation surface can be observed with an electron beam, the observation surface or the back surface of the sample piece is processed by irradiation with the ion beam to thin the sample piece, the inclination of the sample holder stage is changed to adjust the incidence angle of the ion beam on the observation surface or the back surface so that the observation surface and the back surface are processed in parallel, and the electron beam is irradiated onto the observation surface or the back surface that has been processed by the ion beam to observe the processed state of the observation surface or the back surface.

[0012] In one embodiment, the method for preparing and observing a sample piece involves irradiating a wafer with an ion beam to process the sample piece so that the observation surface is the plane or cross-section of the wafer, attaching a sample piece transfer mechanism to the processed sample piece to extract and separate it from the wafer, mounting the sample piece on a carrier on a sample piece holder mounted on a tiltable and rotatable sample piece holder stage so that the observation surface is parallel to the surface of the carrier, tilting the sample piece holder stage so that the observation surface is parallel to the optical axis of the ion beam, and positioning the sample piece holder so that the tilt axis of the stage on which the sample piece holder stage is mounted intersects with the observation surface. The stage is rotated and tilted around the tilt axis so that the angle of incidence of the ion beam to the observation surface changes, the observation surface or the back surface of the sample piece is processed by irradiation with the ion beam to thin the sample piece, the tilt of the sample piece holder stage is changed to adjust the angle of incidence of the ion beam to the observation surface or the back surface so that the observation surface and the back surface are processed in parallel, and the sample piece holder stage is rotated so that the observation surface or the back surface being processed by the ion beam can be observed by irradiation with an electron beam, and the processed state of the observation surface or the back surface is observed. [Effects of the Invention]

[0013] According to one embodiment, a test piece holder stage having multiple drive axes can control the orientation of a sample piece holder that can mount multiple carriers relative to a wafer stage, and the sample piece holder can be transported independently of the wafer stage. [Brief explanation of the drawing]

[0014] [Figure 1] This is a diagram showing the configuration of the inspection system according to the embodiment. [Figure 2] This is a flowchart outlining the inspection process in the inspection system. [Figure 3] This diagram shows the configuration of a charged particle beam apparatus. [Figure 4]It is an external perspective view of a wafer stage and a sub-stage. [Figure 5] It is an external perspective view of a sub-stage. [Figure 6] It is an external perspective view of a holder. [Figure 7] It is a diagram showing an example of the structure of a carrier. [Figure 8] It is a diagram schematically showing the structure of a formed sample piece. [Figure 9] It is a diagram for explaining the process of transferring a sample piece to a carrier. [Figure 10] It is a flowchart showing the process when a charged particle beam device performs a first operation. [Figure 11] It is a diagram showing the appearance of a sub-stage, a holder, and a carrier during automatic cross-section sampling. [Figure 12] It is a flowchart showing the transfer process during automatic cross-section sampling. [Figure 13] It is a diagram showing the appearance of a sub-stage, a holder, and a carrier during automatic plane sampling. [Figure 14] It is a flowchart showing the transfer process during automatic plane sampling. [Figure 15] It is a flowchart showing the process of a second operation when performing a first method in the finishing process. [Figure 16] It is a flowchart showing the process of a second operation when performing a second method in the finishing process. [Figure 17] It is a diagram schematically showing the relationship between an ion beam and a sample piece during the first process of the finishing process. [Figure 18] It is a flowchart for explaining the first process of the finishing process. [Figure 19] It is a diagram schematically showing the appearance of the observation surface of a sample piece. [Figure 20] It is a diagram schematically showing the appearance of a sub-stage, a holder, and a carrier mounted on the holder when performing the second process of the finishing process. [Figure 21] It is a diagram schematically showing the relationship between an ion beam and a sample piece during the second process of the finishing process. [Figure 22] This diagram schematically shows the positional relationship between the sample piece and the needle during attitude-controlled automatic sampling. [Figure 23] This diagram schematically shows the appearance of the substage, holder, and carrier during automatic sampling with attitude control. [Figure 24] This flowchart shows the relocation process during automatic sampling for attitude control. [Modes for carrying out the invention]

[0015] The embodiments of this disclosure will be described in detail below with reference to the drawings. In the drawings, the same parts are generally denoted by the same reference numerals, and repeated descriptions are omitted. In the drawings, the representation of components may not show their actual location, size, shape, and extent in order to facilitate understanding of the invention.

[0016] In explanations, when describing program-based processing, the focus may sometimes be on the program, functions, or processing units. However, the core hardware component is the processor, or a controller, device, computer, or system composed of such a processor. A computer, using its processor, executes processing according to a program read into memory, utilizing resources such as memory and communication interfaces as appropriate. This realizes the specified functions and processing units. A processor is composed of semiconductor devices such as a CPU or GPU. A processor is composed of devices and circuits capable of performing specified calculations. Processing is not limited to software program processing; it can also be implemented using dedicated circuits. FPGAs, ASICs, CPLDs, etc., can be used as dedicated circuits.

[0017] The program may be pre-installed as data on the target computer, or it may be distributed as data to the target computer from the program source. The program source may be a program distribution server on a communication network, or a non-transient computer-readable storage medium (e.g., a memory card). The program may consist of multiple modules. The computer system may consist of multiple devices. The computer system may consist of a cloud computing system, an IoT system, etc. Various types of data and information may be, but are not limited to, structures such as tables and lists.

[0018] <Embodiment> [Overall System Configuration] A charged particle beam apparatus and an inspection system equipped with a charged particle beam apparatus according to embodiments of the present disclosure will be described below with reference to the drawings. Figure 1 is a schematic diagram showing the general configuration of the inspection system 1 of the embodiment.

[0019] The inspection system 1 includes a sample preparation mechanism 1a, a sample observation mechanism 1c, and a control mechanism such as a higher-level control unit 101. As shown in Figure 1, the sample preparation mechanism 1a is a charged particle beam apparatus 10. The charged particle beam apparatus 10 as the sample preparation mechanism 1a is, for example, a FIB-SEM apparatus. The sample observation mechanism 1c is, for example, a sample observation apparatus 30 such as a TEM apparatus.

[0020] The higher-level control unit 101, acting as a control mechanism, controls each controller, which is a control unit provided for each device. Each device's controller manages information about its own device and controls its processing operations. These controllers may be built into each device or connected externally. The controllers of each device may communicate with each other as appropriate. The controllers for each device may also be configured to communicate with each other and cooperate to control their respective devices.

[0021] The inspection system 1 receives inspection instructions and information on the areas to be inspected from the manufacturing management system 150 of the semiconductor manufacturing plant. The inspection system 1 receives the wafer 3, which is the sample to be inspected, from the semiconductor manufacturing line 1d of the semiconductor manufacturing plant by transport. The transported wafer 3 is set in the charged particle beam apparatus 10. The wafer 3 is transported between the semiconductor manufacturing line 1d and the charged particle beam apparatus 10 of the inspection system 1 by a predetermined transport mechanism. For example, the FOUP, which is the container in which the wafer 3 is stored, is transported by an automated transport system or by manual transport by an operator.

[0022] The FIB-SEM apparatus, which is a charged particle beam apparatus 10, forms and prepares a sample piece 4 by thinning a designated area (site) of the transported wafer 3. The charged particle beam apparatus 10 removes the formed and prepared sample piece 4 from the wafer 3 and transfers it to the carrier (LC: Lamella Carrier) 5. The TEM apparatus, which is a sample piece observation apparatus 30, observes and analyzes the cross-section or plane of the sample piece 4 on the carrier 5, and generates and outputs the resulting data 9, etc.

[0023] Various types of data and information are exchanged between the devices of the inspection system 1 via the upper control unit 101 as needed. These types of data and information include, for example, data indicating the inspection target position on the wafer 3 surfaces, data indicating the position where the sample piece 4 was successfully created, and data indicating the position of the sample piece 4 mounted on the carrier 5. The inspection result data 9 also includes detection signals related to secondary electrons generated from the sample piece 4 irradiated with the beam, images obtained from the detection signals, data obtained as a result of processing the images, and data related to X-rays generated from the sample piece 4.

[0024] The inspection system 1 performs processing operations such as creating a sample piece 4 at a specified location on a specified wafer 3 and moving the sample piece 4 to a specified location on a specified carrier 5, with each device responsible for this operation. The system controls and manages information such as these processing operations, status, and location. The inspection system 1 then outputs the inspection result of the sample piece 4 as data 9.

[0025] A sample piece 4 is transported between the charged particle beam apparatus 10 and the sample piece observation apparatus 30 by a transport mechanism 90. For example, the carrier 5 on which the sample piece 4 has been moved is transported by an automated transport system. It is also possible to transport and return wafers 3 from the charged particle beam apparatus 10 to the semiconductor manufacturing line 1d by a transport mechanism (not shown). FOUPs and carriers 5 are used during various transport operations. An FOUP is a container filled with an inert gas such as nitrogen, and wafers 3 and other materials can be inserted into and removed from the container for storage.

[0026] The wafer 3 used in this embodiment consists of a semiconductor substrate on which p-type or n-type impurity regions are formed, semiconductor elements such as transistors formed on the semiconductor substrate, and wiring layers formed on the semiconductor elements. The sample piece 4 is a portion formed on a part of the wafer 3 and removed. Therefore, the sample piece 4 similarly includes the structure of the semiconductor substrate, semiconductor elements, wiring layers, etc. of the wafer 3. Furthermore, while this embodiment mainly focuses on the inspection of sample pieces 4 of wafer 3 used in semiconductor manufacturing lines, it is not limited to this, and the sample may be a structure used in technologies other than semiconductor technology.

[0027] [Processing flow of the inspection system] Figure 2 is a flowchart illustrating the processing flow of the inspection system 1. While it is preferable that each process shown in the flowchart of Figure 2 be automatically executed and controlled by the higher-level control unit 101, it is also possible to partially control some of them manually. For example, in each of the steps shown below, an operator may press the start button at the beginning of the device's processing.

[0028] In step S101, the FOUP containing the wafer 3 to be inspected, i.e., the wafer to be subjected to cross-sectional or surface analysis, is transported from the semiconductor manufacturing line 1d to the charged particle beam apparatus 10 via a transport mechanism. The charged particle beam apparatus 10 receives the FOUP and places the wafer 3 on the stage. At this time, the upper control unit 101 of the charged particle beam apparatus 10 acquires data and information such as inspection target information and inspection instructions for the wafer 3 from the manufacturing management system 150.

[0029] In step S102, the upper control unit 101 instructs the FIB-SEM device in the charged particle beam device 10 to perform a thinning process to form and produce one or more sample pieces 4 on the wafer 3. Based on information received from the manufacturing management system 150, the charged particle beam device 10 positions its field of view at the inspection target position (site) on the wafer 3 by moving the stage. Then, the charged particle beam device 10 forms the sample pieces 4 by irradiating the inspection target position with a beam which is FIB.

[0030] In step S103, the upper control unit 101 instructs the charged particle beam apparatus 10 to perform a transfer process to move the sample piece 4 formed on the wafer 3 onto the carrier 5. In step S104, the upper control unit 101 instructs the transport mechanism 90 to perform a transport process to transport the carrier 5, on which the sample piece 4 is mounted, from the charged particle beam apparatus 10 to the sample piece observation apparatus 30. In step S105, the upper control unit 101 instructs the TEM apparatus in the sample piece observation apparatus 30 to perform cross-sectional or planar observation using TEM images. The results of the analysis and inspection performed by the cross-sectional or planar observation are stored and output as data 9.

[0031] [Configuration of a charged particle beam device] Figure 3 is a schematic diagram showing the configuration of the charged particle beam apparatus 10. The charged particle beam apparatus 10 includes a sample chamber 20, an ion beam column 11, an ion beam column controller 131, an electron beam column 12, an electron beam column controller 132, a wafer stage 21, a wafer stage controller 133, a substage 22, a substage controller 134, a needle 112, a needle controller 142, etc. The charged particle beam apparatus 10 also includes a charged particle detector 109, a detector controller 136, a sample chamber controller 137, an integrated control unit 130, a computer system 100, etc.

[0032] The charged particle beam apparatus 10 is also equipped with a wafer loading mechanism, etc. (not shown). The wafer loading mechanism is a mechanism for loading wafers 3 in the FOUP into the sample chamber 20 and unloading wafers 3 in the sample chamber 20 into the FOUP.

[0033] The sample chamber 20 is equipped with an ion beam column 11, an electron beam column 12, a wafer stage 21, a substage 22, and a needle 112, among other things.

[0034] The ion beam column 11 has its optical axis OA1 (shown by a dashed line) aligned vertically. The electron beam column 12 has its optical axis OA2 (shown by a dashed line) aligned in a direction inclined with respect to the optical axis OA1 of the ion beam column 11. The ion beam column 11 emits an ion beam b11, which is the FIB, towards the cross point CP1, and the electron beam column 12 emits an electron beam b12 towards the cross point CP1. The ion beam b11 emitted from the ion beam column 11 and the electron beam b12 emitted from the electron beam column 12 are focused at the cross point CP1, which is the intersection of their respective optical axes. In this example, the optical axis of the electron beam column 12 is inclined with respect to the optical axis of the ion beam column 11, but the configuration is not limited to this.

[0035] The ion beam column 11 includes components necessary for a FIB (Focused Ion Beam) device, such as an ion source 11a for generating the ion beam b11, lenses 11b and 11c for focusing the ion beam b11, an objective lens 11d, and a deflector 11e for scanning the ion beam b11. In other words, the ion beam column 11 is a charged particle beam microscope tube that irradiates a charged particle beam.

[0036] The electron beam column 12 includes components necessary for a scanning electron microscope (SEM) device, such as an electron source 12a for generating the electron beam b12, lenses 12b and 12c for focusing the electron beam b12, an objective lens 12d, and a deflector 12e for scanning the electron beam b12. In other words, the electron beam column 12 is a charged particle beam microscope tube that irradiates a charged particle beam.

[0037] The wafer stage 21 is a movable stage on which a sample wafer 3 can be placed. The substage 22 is a movable stage on which a sample piece 4 or a carrier 5 can be placed. Details of the wafer stage 21 and substage 22 will be described later. The wafer stage 21, substage 22, etc., can move in a planar or rotational manner. The integrated control unit 130 controls the movement of the wafer stage 21 via the wafer stage controller 133 to position it so that the beam can be irradiated onto the target area on the surface of the wafer 3 (for example, the area where the sample piece 4 is formed). The integrated control unit 130 controls the attitude of the carrier 5 mounted on the substage 22 by controlling the movement of the substage 22 via the substage controller 134.

[0038] The charged particle detector 109 detects charged particles generated when the ion beam b11 irradiates the sample, and charged particles generated when the electron beam b12 irradiates the sample, as detection signals. The detector controller 136 processes the detection signals from the charged particle detector 109 to create an image. The detector controller 136 includes a processing unit implemented by a circuit or program.

[0039] Furthermore, the sample chamber 20 may also be equipped with other types of detectors, such as an X-ray detector and a backscattered electron detector for detecting backscattered electrons generated from the sample.

[0040] The needle 112 is positioned inside the sample chamber 20 so as to be able to reach the cross point CP1. The needle 112 is controlled and driven by the needle controller 142 to hold the sample piece 4 that has been separated and extracted (lifted out) from the wafer 3, and functions as a sample piece transfer mechanism to transport and move the sample piece 4 to the carrier 5. Furthermore, since the needle 112 can move planar, vertically, and rotationally, the orientation of the sample piece 4 can be freely changed when the needle 112 is holding the sample piece 4.

[0041] The sample chamber 20 also includes other components, such as a gas supply unit for supplying gases used for etching and deposition processes (not shown in the diagram). The vacuum level of the sample chamber 20 is controlled by the sample chamber controller 137. The sample chamber 20 may be mounted on a vibration isolation table 201 to prevent vibration. In addition to the above-mentioned components, the sample chamber 20 may also be equipped with a vacuum pump, a cold trap, or an optical microscope for vacuum evacuation.

[0042] Furthermore, the charged particle beam apparatus 10 is not limited to the FIB-SEM apparatus described above; a FIB apparatus without an SEM mechanism may be used, or a FIB apparatus equipped with an optical microscope instead of an SEM mechanism may be used.

[0043] The integrated control unit 130 controls the entire charged particle beam apparatus 10 and its various components. The integrated control unit 130 is electrically connected to the controllers of each component, such as the wafer stage controller 133 and the sub-stage controller 134, and can communicate with each other. The integrated control unit 130 controls the controllers of each component using control signals. Multiple controllers may be combined into a single controller. Each controller may be implemented using a computer system or dedicated circuitry. The computer system 100 is connected to the integrated control unit 130. The integrated control unit 130 controls the operation of the entire charged particle beam apparatus 10 and its various components according to instructions from the computer system 100.

[0044] The computer system 100 provides a user interface, including a GUI, to users of the charged particle beam apparatus 10, and accepts various instructions and settings from the user. The computer system 100 has built-in or externally connected input devices 162, output devices 161, and storage devices. Examples of input devices 162 include a keyboard, mouse, touch panel, and microphone. Examples of output devices 161 include a display, printer, speaker, and lamp. The display shows screens with a GUI. The screen shows images captured by the charged particle beam apparatus 10, setting information, user instruction information, etc.

[0045] Users, such as operators, can view various information and images on the screen displayed on the display. Users input various instructions and settings on the screen using a keyboard or the like. The computer system 100 transmits instructions and settings to the integrated control unit 130 based on the input instructions and settings. The integrated control unit 130 and the computer system 100 may be configured as an integrated unit.

[0046] [Wafer stage 21 and substage 22] Figures 4(A) and 4(B) are external perspective views of the wafer stage 21 and substage 22 located within the sample chamber 20. Figure 4(A) shows the case where the rotation angle around the T-axis, which will be described later, is 0°, and Figure 4(B) shows the case where the rotation angle around the T-axis is 20°.

[0047] The following explanation will use a Cartesian coordinate system consisting of the x, y, and z axes, as shown in Figure 4. The z axis is set along the vertical direction, with the area above the sample chamber 20, i.e., above the charged particle beam apparatus 10, located on the z-axis+ side. The x axis is set perpendicular to the z axis, and the y axis is set perpendicular to both the x and z axes. With the Cartesian coordinate system in place, the ion beam column 11 described above can be said to irradiate the ion beam b11 from the z-axis+ side towards the z-axis- side. That is, the optical axis OA1 of the ion beam column 11 is parallel to the z axis. The electron beam column 12 irradiates the electron beam b12 from the z-axis+ and y-axis+ side towards the z-axis- and y-axis- side. That is, the optical axis OA2 of the electron beam column 12 is inclined with respect to the xy plane. The wafer stage 21 and substage 22 are positioned by the wafer stage controller 133 or substage controller 134 so that they can be processed and observed by the ion beam b11 and electron beam b12 irradiated in the above direction.

[0048] [Wafer Stage 21] The wafer stage 21 is configured to support and move the wafer 3. Specifically, the wafer stage 21 has an x-base 210, a y-base 211, a z-base 212, a rotating base 213, and a support mechanism 214. As shown in Figure 4(A), when the rotation angle of the T-axis, which will be described later, is 0°, the x-base 210, y-base 211, z-base 212, and rotating base 213 are provided in the sample chamber 20 in the order described above, starting from the lower side, i.e., the z-axis side.

[0049] The x-base 210 is a plate-shaped member having a long side extending in the y-axis direction. Below the x-base 210, an x-axis drive mechanism 215 is provided, which includes, for example, a motor, a ball screw, and a guide member extending along the x-axis. When the motor of the x-axis drive mechanism 215 is driven, the ball screw rotates, and the x-base 210 moves along the x-axis, which is the first direction. As the x-base 210 moves along the x-axis, the y-base 211, z-base 212, and rotary base 213, which are provided above the x-base 210, also move along the x-axis, which is the first direction, together with the x-base 210.

[0050] The x-axis drive mechanism 215 is controlled by the integrated control unit 130 via the wafer stage controller 133. The movement of the x-base 210 by the x-axis drive mechanism 215 is controlled by, for example, encoder control or linear scale control, and the x-base 210 is positioned with high precision. The range in which the x-base 210 can move is 0 to 327 mm, which can accommodate, for example, a 300 mm size wafer 3. In addition, a y-axis drive mechanism 216 for moving the y-base 211 is provided on the upper surface of the x-base 210.

[0051] The y-base 211 is a plate-shaped member and is provided on the upper side of the x-base 210. More specifically, the y-base 211 is provided on a y-axis drive mechanism 216 provided on the upper surface of the x-base 210. The y-axis drive mechanism 216 includes, for example, a motor, a ball screw, and a guide member extending along a second direction that intersects (orthogonals) with the x-axis. The second direction is the y-axis direction when the rotation angle of the T-axis, described later, is 0° (see Figure 4(A)). When the motor of the y-axis drive mechanism 216 is driven, the ball screw rotates and the y-base 211 moves along the second direction. When the y-base 211 moves along the second direction, the z-base 212 and the rotating base 213, which are provided above the y-base 211, also move along the second direction together with the y-base 211. In other words, the y-base 211 is movable in both the first and second directions.

[0052] The y-axis drive mechanism 216 is controlled by the integrated control unit 130 via the wafer stage controller 133. The movement of the y-base 211 by the y-axis drive mechanism 216 is controlled by, for example, encoder control or linear scale control, and the y-base 211 is positioned with high precision. The range in which the y-base 211 can move is 0 to 327 mm, which accommodates, for example, a 300 mm wafer 3. In addition, a z-axis drive mechanism 217 for moving the z-base 212 is provided on the upper side of the y-base 211.

[0053] The z-base 212 is a plate-shaped member and is provided on the upper side of the y-base 211. More specifically, the z-base 212 is provided on a z-axis drive mechanism 217 provided on the upper surface of the y-base 211. The z-axis drive mechanism 217 includes, for example, a motor, a ball screw, and a wedge-shaped guide member that extends along the x-axis and is inclined with respect to the y-base 211. When the motor of the z-axis drive mechanism 217 is driven, the ball screw rotates, and the z-base 212 moves along the inclined surface of the wedge-shaped guide member. As a result, the z-base 212 moves in a direction perpendicular to the y-base 211, that is, in a third direction perpendicular to the first and second directions. In other words, the z-base 212 is movable in the first, second, and third directions. The third direction is the z-axis direction when the rotation angle of the T-axis, which will be described later, is 0° (see Figure 4(A)). As the z-base 212 moves along the third direction, the rotating base 213, which is located above the z-base 212, also moves along the third direction together with the z-base 212. That is, as shown in Figure 4(A), when the rotation angle around the T-axis is 0°, the z-base 212 moves along the z-axis, and the rotating base 213 moves along the z-axis in conjunction with this movement.

[0054] The z-axis drive mechanism 217 is controlled by the integrated control unit 130 via the wafer stage controller 133. The movement of the z-base 212 by the z-axis drive mechanism 217 is controlled by, for example, encoder control or linear scale control, and the z-base 212 is positioned with high precision.

[0055] The rotating base 213 is provided on the z-base 212. The rotating base 213 is a mounting platform on which the wafer 3 is placed, and is rotatably positioned around the R-axis, which is a first axis intersecting (orthogonal to) the z-base 212. The R-axis, which is the first axis, is parallel to the z-axis when the rotation angle of the T-axis, described later, is 0° (see Figure 4(A)). The rotating base 213 is rotated by a drive mechanism whose drive is controlled by the integrated control unit 130 via the wafer stage controller 133. In this case, for example, the rotating base 213 is rotated by rotating a ceramic ring with an ultrasonic motor, and its rotational direction can be positioned with high precision. The rotating base 213 has an electrostatic chuck. The wafer 3 is placed on the rotating base 213 by being attracted by the electrostatic force of the electrostatic chuck.

[0056] The support mechanism 214 is rotatably held by gears or the like on two side walls of the sample chamber 20 that intersect with the x-axis. The support mechanism 214 rotates about the T-axis, which is a second axis parallel to the x-axis, by the synchronous driving of gears provided on the two sides of the sample chamber 20. The support mechanism 214 integrally supports the x-base 210, y-base 211, z-base 212, and rotating base 213, which are provided above it, by supporting the x-axis drive mechanism 215 provided on the lower side of the x-base 210. As a result, by the rotation of the support mechanism 214 about the T-axis, it becomes possible to tilt the rotating base 213 on which the wafer 3 is placed with respect to the xy plane, for example, as shown in Figure 4(B). In other words, the T-axis is the tilt axis that tilts the wafer stage 21 on which the wafer 3 is placed with respect to the xy plane.

[0057] [Substage 22] The substage 22 is a sample holder stage to which the holder 6, described later, is detachably attached and which can move independently of the wafer stage 21. Specifically, as shown in Figures 4(A) and 4(B), the substage 22 is provided on the z-base 212 of the wafer stage 21 described above. Therefore, as described above, when the wafer stage 21 moves along the first direction axis, second direction, and third direction, the substage 22 also moves along the first direction, second direction, and third direction together with the wafer stage 21. Also, when the wafer stage 21 rotates around the T-axis and tilts with respect to the xy-plane, the substage 22 also rotates around the T-axis and tilts with respect to the xy-plane together with the wafer stage 21.

[0058] Figure 5 is an external perspective view of the substage 22. Note that Figure 5 shows the substage 22 when the rotation angle of the T-axis is 0°. The substage 22 has a mounting section 221 on which the holder 6 on which the carrier 5 is mounted is detachably mounted (loaded), a mounting support section 222 that supports the mounting section 221, and a tilting mechanism 223. The mounting section 221 has a mounting surface (not shown), on which the holder 6 transported by the transport mechanism 90 is placed and mounted. The mounting support section 222 is rotatably attached to the z-base 212 around the θ-axis, which is a third axis intersecting (orthogonal to) the z-base 212. The mounting support section 222 is rotated by a drive mechanism controlled by the substage controller 134.

[0059] The tilting mechanism 223 is an arm member fixed to the mounting part 221. It is mounted on the mounting support part 222 so as to be rotatable about the F-axis, which is a fourth axis intersecting (orthogonal to) the θ-axis at one end, and a gear is formed at the other end. Therefore, when the driving force of the drive mechanism controlled by the substage controller 134 is transmitted via the gear, the tilting mechanism 223 rotates about the F-axis. As the tilting mechanism 223 rotates, the mounting part 221 fixed to the tilting mechanism 223 also rotates about the F-axis. As a result, the mounting part 221 and the holder 6 tilt with respect to a plane parallel to the z-base 212.

[0060] Furthermore, when the mounting support 222 rotates about the θ axis due to the driving force of the drive mechanism controlled by the substage controller 134, the tilting mechanism 223 and the mounting part 221 rotate about the θ axis along with the rotation of the mounting support 222. As a result, the mounting part 221 rotates in a plane parallel to the z base 212, about an axis perpendicular to the z base 212. Note that Figure 5 illustrates the case where the θ axis and z axis are parallel, and the F axis and y axis are parallel.

[0061] Because the substage 22 has the above configuration, the substage 22 moves (rotates) independently of the wafer stage 21 about the θ axis and moves (tilts) independently of the wafer stage 21 about the F axis. As a result, the holder 6 and the carrier 5 mounted on the holder 6 can also rotate independently of the wafer stage 21 about the θ axis and tilt about the F axis. The carrier 5 mounted on the holder 6 attached to the mounting section 221 and the wafer 3 placed on the rotating base 213 are designed to have the same height, i.e., the distance along the third direction from the z base 212.

[0062] [Holder 6] The holder 6 is a sample holder that carries multiple carriers 5 and is detachably attached to the substage 22, which is a stage for sample holders. Figure 6 is an external perspective view of the holder 6. The holder 6 has a columnar shape. The following explanation will use a Cartesian coordinate system consisting of the u-axis, v-axis, and w-axis, as shown in Figure 6. The u-axis is an axis set along the longitudinal direction of the holder 6. The v-axis is an axis perpendicular to the u-axis and set along the short direction of the holder 6. The w-axis is an axis perpendicular to the u-axis and v-axis and set along the height direction of the holder 6.

[0063] A carrier holding portion 61 is provided on the w-axis positive side surface 60a of the holder 6 for holding the mounted carrier 5. The carrier holding portion 61 is a plate-shaped member and is biased in the w-axis direction by a biasing portion 62 such as a coil spring provided on the w- side. The carrier 5 is mounted on the holder 6 by being sandwiched between the w-axis negative side surface of the carrier holding portion 61 and surface 60a. As shown in Figure 6, the carrier 5 held and mounted by the carrier holding portion 61 protrudes towards the v-axis positive side beyond the v-axis positive side surface 60b of the holder 6. Note that Figure 6 shows a case where the holder 6 has four carrier holding portions 61, but the number of carrier holding portions 61 may be three or fewer, or five or more.

[0064] The holder 6 is attached to the mounting portion 221 of the substage 22 described above. As described above, since the mounting portion 221 to which the holder 6 is attached is fixed to the tilting mechanism 223, it can be said that the holder 6 is detachably attached to the substage 22 independently of the tilting mechanism 223.

[0065] Furthermore, when the surface 60a of the holder 6 attached to the substage 22 is parallel to the z-base 212 on the z-axis + side, the rotation angle of the F-axis of the substage 22 is set to 0°. Also, when the + and - directions of the u-axis of the holder 6 attached to the substage 22 coincide with the + and - directions of the y-axis, the rotation angle of the θ-axis of the substage 22 is set to 0°. Accordingly, Figure 5 above shows the case where the rotation angle of the θ-axis of the substage 22 is 0° and the rotation angle of the F-axis is 90°.

[0066] [Career 5] Figure 7 shows an example of the structure of carrier 5. This carrier 5 is sometimes called a lamellar grid, TEM mesh, etc. This carrier 5 includes a half-moon shaped base body 50 and a plurality of pillars 53 protruding from a straight section 51 within the surface of the base body 50. Each pillar 53 is a sample piece support part having a structure on which a sample piece 4 can be mounted and held.

[0067] At both ends of the base body 50 where pillars 53 are not provided (the circumference in a plan view of the top surface of the carrier 5), marks 55 are provided, which are formed by holes that penetrate the base body 50. The marks 55 are provided as marks of different shapes, and circular and triangular marks 55 are shown here as examples. The marks 55 make it easy to distinguish the front and back of the carrier 5. Also, when deciding which pillar 53 to move the sample piece 4 to, the desired pillar 53 can be found by referring to the marks 55, making it easy to identify the relocation position.

[0068] [Operation of the charged particle beam device] The operation of the charged particle beam apparatus 10 having the above configuration will now be described. The charged particle beam apparatus 10 performs one of the following operations: a first operation in which a sample piece 4 is formed, fabricated, and transferred (sampled) from the wafer 3 and the sampled sample piece 4 is observed; a second operation in which finishing processing is performed on the sampled sample piece 4; or a third operation in which only the sampling of the sample piece 4 is performed. The first, second, and third operations will be described below.

[0069] [1st action] As a first operation, the charged particle beam apparatus 10 undergoes preparation processing, followed by processing, relocation, and observation processes included in the manufacturing and observation method.

[0070] [Preparation Process] The integrated control unit 130 performs preparatory processing as a preliminary step for the process of forming and fabricating the sample piece 4. This preparatory processing corresponds to step S101 shown in Figure 2 above. Specifically, the wafer 3 is loaded onto the rotating base 213 of the wafer stage 21, and the holder 6 with the carrier 5 mounted on it is loaded onto the substage 22. The ion beam b11 and electron beam b12 irradiated from the ion beam column 11 and electron beam column 12, respectively, are adjusted.

[0071] The integrated control unit 130 controls the wafer stage controller 133 to adjust the x, y, z, T, and R axis positions of the wafer stage 21, thereby aligning the wafer 3. The integrated control unit 130 then receives position data from the higher control unit 101 indicating the position on the wafer 3 where the sample piece 4 will be formed and manufactured. Based on the input position data, the integrated control unit 130 controls the wafer stage controller 133 to move the wafer stage 21, positioning the sample piece 4 to be formed and manufactured at the cross point CP1.

[0072] [Processing] Once the above preparation process is complete, the integrated control unit 130 performs a processing operation to process the wafer 3 and form a sample piece 4. This processing operation corresponds to step S102 shown in Figure 2 above.

[0073] Figure 8 schematically shows the structure of a sample piece 4 formed and manufactured by processing. Figure 8 shows a sample piece 4 formed and manufactured when observing the cross-sectional structure of a wafer 3 (cross-sectional observation). In this case, the sample piece 4 is a thin piece whose width in the y-axis direction is thinner than its width in the x-axis and z-axis directions. In this case, the cross-section of the wafer 3 becomes the observation surface 40 of the sample piece 4, which will be described later. Note that when a sample piece 4 is formed and manufactured for observing the planar structure of the wafer 3 (planar observation), the sample piece 4 should be a thin piece whose width in the z-axis direction is thinner than its width in the x-axis and y-axis directions. In this case, the plane of the wafer 3 becomes the observation surface of the sample piece 4, which will be described later.

[0074] A protective film is formed on the wafer 3 based on the shape of the sample piece 4. In this case, the protective film is formed on the surface of the wafer 3 by pouring a protective film material, such as carbon gas, into the wafer 3 while the position where the sample piece 4 is formed and fabricated is observed by irradiating the wafer 3 with ion beam b11 from the ion beam column 11. The ion beam column 11 irradiates the wafer 3 outside the protective film with ion beam b11, etching a portion of the wafer 3. This forms and fabricates the sample piece 4.

[0075] As a result, during the processing, the wafer 3 is irradiated with the ion beam b11, and a sample piece 4 is processed with the planar or cross-section of the wafer 3 as the observation surface. At this point, the sample piece 4 is connected to the wafer 3 by the connection point 4a. In other words, at this point, the sample piece 4, the connection point 4a and the wafer 3 are integrated, and as will be described later, when the sample piece 4 is transferred to the carrier 5 by the needle 112, it separates from the connection point 4a.

[0076] [Relocation process] In the transfer process, a needle 112, which is a sample transfer mechanism, is attached to the sample piece 4 processed in the processing process, thereby extracting and separating (lifting out) the sample piece 4 from the wafer 3. The lifted-out sample piece 4 is then mounted on a carrier 5 on a holder 6 attached to a substage 22, with the observation surface 40 of the sample piece 4 parallel to the surface of the carrier 5. This process corresponds to step S103 shown in Figure 2 and is performed using an automated microsampling method.

[0077] Figure 9 is an explanatory diagram illustrating the relocation process. First, as shown in Figure 9(A), the needle 112 is controlled by the needle controller 142 to approach the sample piece 4. Deposition processing is performed in the sample chamber 20, and the needle 112 is bonded to a part of the sample piece 4. As shown in the figure, the needle 112 is bonded to the side surface 4b of the sample piece 4 opposite to the connection point 4a. The ion beam column 11 irradiates the connection point 4a connecting the sample piece 4 and the wafer 3 with ion beam b11 to perform etching. As a result, the sample piece 4 is cut, extracted, and separated from the wafer 3.

[0078] Next, as shown in Figure 9(B), the sample piece 4 held by the needle 112 is moved to the position of the pillar 53 on the carrier 5 by the movement of the needle 112 controlled by the needle controller 142. As mentioned above, since the carrier 5 is mounted on a holder 6 attached to the substage 22, the carrier 5 is located in a different position from the wafer 3. When performing cross-sectional observation, the substage 22 is driven to a position where both the F-axis and θ-axis rotation angles are 90°. When performing planar observation, the substage 22 is driven to positions where the F-axis and θ-axis angles are 0° and 90°, respectively. Then, the needle controller 142 controls the movement of the needle 112, and the sample piece 4 approaches the position of the pillar 53. The operation of each part in the transfer of the sample piece 4 to the carrier 5 will be described in detail later.

[0079] As shown in Figure 9(C), the side 4c of the sample piece 4 opposite to the side 4b where it is connected to the needle 112 is close to the pillar 53. Deposition processing is performed near this side 4c, thereby bonding the pillar 53 and the sample piece 4. At this time, the observation surface 40 of the sample piece 4, which is a cross-section or plane of the wafer 3, is mounted parallel to the surface of the carrier 5. The ion beam column 11 then irradiates the area on side 4b where the sample piece 4 and the needle 112 are connected with ion beam b11 to perform etching. As a result, the sample piece 4 is cut away from the needle 112.

[0080] In Figure 9, a case is shown where one sample piece 4 is supported by one pillar 53. However, by making the pillar 53 taller, multiple sample pieces 4 may be supported by one pillar 53.

[0081] [Observation process] During the observation process, the substage 22 is rotated around the θ axis so that the observation surface 40 of the sample piece 4 is irradiated by the electron beam b12 and becomes observable. When the observation surface 40 of the sample piece 4 is observed, the substage 22 is rotated around the θ axis so that the back surface of the observation surface 40 of the sample piece 4 is irradiated by the electron beam b12 and becomes observable. Specifically, when the sample piece 4 is moved by the relocation process so that it is supported by the pillar 53 of the carrier 5, the electron beam column 12 irradiates the observation surface 40 of the sample piece 4 supported by the pillar 53 with the electron beam b12. For example, when performing cross-sectional observation, the substage 22 is controlled by the substage controller 134 and driven to a position where the rotation angle of the θ axis is 90°. That is, the observation surface 40 of the sample piece 4 moved to the carrier 5 faces the electron beam column 12.

[0082] The charged particle detector 109 detects charged particles generated from the observation surface 40 of the sample piece 4, and the detector controller 136 processes the detection signals contained in the detected charged particles and generates an image. From this image, it is possible to analyze the structure of the observation surface 40 of the sample piece 4. Furthermore, if the charged particle beam apparatus 10 has an X-ray detector, the X-ray detector can detect X-rays generated from the observation surface 40 of the sample piece 4, and the materials constituting the observation surface 40 of the sample piece 4 can also be analyzed.

[0083] When observing the back surface of the sample piece 4 opposite to the observation surface 40 observed as described above, the substage 22 is controlled by the substage controller 134 and driven to a position where the rotation angle of the θ-axis, which has been rotated 180° around the θ-axis, is -90°. That is, the back surface of the sample piece 4 faces the electron beam column 12. Then, in the same manner as when the observation surface 40 of the sample piece 4 is observed, the back surface of the sample piece 4 is irradiated with the electron beam b12 and the observation process is performed. Note that the substage 22 being driven to the position of 90° or -90° on the θ-axis is just one example. The rotation angle of the θ-axis can be any value depending on the observation location.

[0084] After the charged particle beam apparatus 10 has performed the above processing operation on a specified number of sample pieces 4, the wafer 3 is removed (unloaded) from the rotating base 213 of the wafer stage 21, and the holder 6 with the carrier 5 attached is removed (unloaded) from the substage 22.

[0085] Figure 10 is a flowchart illustrating the operation flow of the charged particle beam apparatus 10. Each process shown in Figure 10 is automatically executed and controlled by the integrated control unit 130.

[0086] In step S201, the integrated control unit 130 loads the wafer 3 onto the rotating base 213 of the wafer stage 21 and loads the holder 6 on which the carrier 5 is mounted onto the substage 22. In step S202, the integrated control unit 130 controls the ion beam column controller 131 and the electron beam column controller 132 to adjust the ion beam b11 and electron beam b12 irradiated from the ion beam column 11 and electron beam column 12, respectively.

[0087] In step S203, the integrated control unit 130 controls the wafer stage controller 133 to drive the wafer stage 21 and align the position of the wafer 3. In step S204, the integrated control unit 130 controls the wafer stage controller 133 to move the wafer stage 21 based on the position data input from the higher control unit 101, and positions the sample piece 4 to be formed at the cross point CP1. The processes from steps S201 to S204 described above constitute the preparation process.

[0088] In step S205, as a processing step, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the wafer 3 with ion beam b11 from the ion beam column 11. As described above, the ion beam column 11 irradiates the wafer 3 with ion beam b11 on the part of the wafer 3 outside the protective film formed on the wafer 3, and a sample piece 4 is formed and manufactured by etching a part of the wafer 3.

[0089] In step S206, the integrated control unit 130 controls the needle controller 142 to bring the needle 112 closer to the sample piece 4. The integrated control unit 130 adheres the needle 112 to a portion of the sample piece 4 by deposition. In step S207, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the connection point 4a of the ion beam column 11 with the ion beam b11 to perform etching. As a result, the sample piece 4 is cut from the wafer 3. In step S208, the integrated control unit 130 controls the needle controller 142 to move the needle 112 and lift the sample piece 4 off the wafer 3.

[0090] In step S209, the integrated control unit 130 controls the needle controller 142 to move the needle 112 to the position of the pillar 53 on the carrier 5. The integrated control unit 130 performs deposition processing near the side surface 4c of the sample piece 4 to bond the pillar 53 and the sample piece 4. Then, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the ion beam b11 onto the ion beam column 11 at the point 4d where the sample piece 4 and the needle 112 are connected, thereby etching the sample piece 4. As a result, the sample piece 4 is cut from the needle 112 and transferred to the pillar 53, i.e., the carrier 5. The processes in steps S206 to S209 described above constitute the transfer process.

[0091] In step S210, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the observation surface 40 of the sample piece 4, supported by the pillar 53, with the electron beam column 12 using the electron beam column 12. The integrated control unit 130 then causes the charged particle detector 109 to detect charged particles generated from the observation surface 40 of the sample piece 4, processes the detection signals contained in the charged particles, and performs observation processing to create an image.

[0092] In step S211, it is determined whether the specified number of sample pieces 4 have been formed and prepared, transferred to the carrier 5, and observed. If each process has been performed on the specified number of sample pieces 4, the integrated control unit 130 makes a positive determination, and the process proceeds to step S212. If the number of sample pieces 4 that have undergone the above processes has not reached the specified number, the integrated control unit 130 makes a negative determination, and the process returns to step S204.

[0093] In step S212, the integrated control unit 130 unloads the wafer 3 from the rotating base 213 of the wafer stage 21 and unloads the holder 6 with the carrier 5 attached from the substage 22, thereby ending the process.

[0094] [Details of the relocation process] The details of step S209 in the relocation process described above will now be explained. The rotation angles of the F-axis and θ-axis of the substage 22 differ between the relocation process when performing cross-sectional observation (automatic cross-sectional microsampling) and the relocation process when performing planar observation (automatic planar sampling). The following explanation will be given separately for the case where automatic cross-sectional sampling is performed on the sample piece 4 and the case where automatic planar sampling is performed.

[0095] [Transfer process for cross-sectional observation of sample pieces (automatic cross-sectional sampling)] Figure 11 is a schematic diagram showing the appearance of the substage 22, the holder 6 attached to the substage 22, and the carrier 5 mounted on the holder 6. Figure 11(A) shows the appearance of the substage 22, holder 6, and carrier 5 viewed from the z-axis+ side, and Figure 11(B) shows the appearance of the substage 22, holder 6, and carrier 5 viewed from the y-axis+ side.

[0096] As described above, when performing cross-sectional observation, the substage 22 is driven to a position where both the F-axis and θ-axis rotation angles are 90°. Therefore, as shown in Figures 11(A) and 11(B), the surface of the carrier 5 substrate 50 is parallel to the zx plane and faces the y-axis+ side, and the pillar 53 protrudes toward the z-axis+ side. In other words, the surface of the carrier 5 substrate 50 faces the electron beam column 12.

[0097] In this state, the ion beam column 11 and the electron beam column 12 irradiate the carrier 5 with ion beam b11 and electron beam b12, respectively. While the ion beam b11 and electron beam b12 are irradiating, the needle 112 moves to a position where it is not irradiated by the ion beam b11 and electron beam b12, for example, to a retracted position on the z-axis+ side.

[0098] Charged particles generated by irradiation with ion beam b11 are detected as detection signals by the charged particle detector 109, and the detection signals are imaged by the detector controller 136. As shown in Figure 11(B), the carrier 5 is irradiated by ion beam b11 from the z-axis+ side. Therefore, the detector controller 136 generates an image (LC image) of the carrier 5 as viewed from the z-axis+ side. The integrated control unit 130 uses this image to detect whether or not there is a misalignment of the carrier 5 in the x and y directions. If there is a misalignment, the wafer stage controller 133 moves the z-base 212 along the x and y axes to adjust the misalignment of the substage 22.

[0099] Charged particles generated by irradiation with electron beam b12 are detected as detection signals by the charged particle detector 109, and the detection signals are imaged by the detector controller 136. As shown in Figure 11(B), the carrier 5 is irradiated by electron beam b12 from the y-axis + side. Therefore, the detector controller 136 generates an image (LC image) of the carrier 5 as viewed from the y-axis + side. The integrated control unit 130 uses this image to detect whether or not there is a misalignment of the carrier 5 in the zx direction. If there is a misalignment, the wafer stage controller 133 moves the z base 212 along the x and z axes to adjust the misalignment of the substage 22.

[0100] Furthermore, the integrated control unit 130 determines the position of the pillar 53 to which the sample piece 4 will be moved based on the LC image viewed from the z-axis + side and the LC image viewed from the y-axis + side. The needle controller 142 moves the needle 112 to the vicinity of the pillar 53 determined based on the LC image. At this time, the integrated control unit 130 calculates the amount of movement of the needle 112 based on the coordinates of the retracted position of the needle 112 and the coordinates of the position of the pillar 53 determined on the LC image. The needle controller 142 moves the needle 112 by the calculated amount of movement.

[0101] In this state, the ion beam column 11 and the electron beam column 12 irradiate the sample piece 4 attached to the needle 112 with ion beam b11 and electron beam b12, respectively. Charged particles generated by irradiation with ion beam b11 are detected as detection signals by the charged particle detector 109, and the detection signals are imaged by the detector controller 136. That is, an image (needle image) of the sample piece 4 and needle 112 as viewed from the z-axis+ side is generated. The integrated control unit 130 uses this image to determine the position of the sample piece 4 in the x and y directions.

[0102] Charged particles generated by irradiation with electron beam b12 are detected as detection signals by the charged particle detector 109, and the detection signals are imaged by the detector controller 136. That is, an image (needle image) of the sample piece 4 and needle 112 as viewed from the y-axis + side is generated. The integrated control unit 130 uses this image to determine the position of the sample piece 4 in the zx direction.

[0103] The integrated control unit 130 calculates the distance between the sample piece 4 and the pillar 53, i.e., the amount of movement of the sample piece 4, based on the position of the sample piece 4 identified based on the needle image and the position of the pillar 53 determined based on the LC image. The needle controller 142 moves the needle 112 by the calculated amount of movement. As a result, the sample piece 4 is moved to a position where it can be adhered to the pillar 53 of the carrier 5. Subsequently, the deposition process described above and the cutting of the needle 112 from the sample piece 4 are performed.

[0104] Figure 12 is a flowchart illustrating the operation flow of the relocation process performed by the charged particle beam apparatus 10 when automatically sampling the cross-section of the sample piece 4. Each process shown in Figure 12 is automatically executed and controlled by the integrated control unit 130. The processes described below are details of the process of step S209, which is executed in the flowchart of Figure 10 described above.

[0105] In step S300, the integrated control unit 130 controls the wafer stage controller 133 to move the x-base 210, y-base 211, and z-base 212 in the xy plane, moving the substage 22 below the ion beam column 11 and the electron beam column 12 (towards the z-axis). In step S301, the integrated control unit 130 controls the substage controller 134 to move the substage 22 to a position where the rotation angles of both the F-axis and θ-axis are 90°. In step S302, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the carrier 5 with ion beam b11 from the ion beam column 11. Similarly, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the carrier 5 with electron beam b12 from the electron beam column 12. The integrated control unit 130 uses the LC image generated by the detector controller 136 based on the detection signals detected by the charged particle detectors 109 and 110 to calculate the amount of movement from the retracted needle 112 to the pillar 53.

[0106] In step S303, the integrated control unit 130 controls the needle controller 142 to move the needle 112 by the amount of movement calculated in step S302. In step S304, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the sample piece 4 attached to the needle 112 with ion beam b11 from the ion beam column 11. Similarly, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the sample piece 4 attached to the needle 112 with electron beam b12 from the electron beam column 12. The integrated control unit 130 uses the needle image generated by the detector controller 136 based on the detection signal detected by the charged particle detector 109 to calculate the amount of movement of the needle 112 to a position where it can be attached to the pillar 53.

[0107] In step S305, the integrated control unit 130 controls the needle controller 142 to move the needle 112 by the amount of movement calculated in step S304. In step S306, the integrated control unit 130 adheres the needle 112 to a part of the sample piece 4 by deposition as described above. In step S307, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the ion beam b11 onto the ion beam column 11 at the point 4d where the sample piece 4 and the needle 112 are connected, thereby cutting the needle 112 from the sample piece 4 and ending the relocation process.

[0108] [Transfer procedure when observing a sample piece in a planar view (automatic planar sampling)] Figure 13 is a schematic diagram showing the appearance of the substage 22, the holder 6 attached to the substage 22, and the carrier 5 mounted on the holder 6. Figure 13(A) shows the appearance of the substage 22, holder 6, and carrier 5 viewed from the z-axis+ side, and Figure 13(B) is a magnified view of the carrier 5 shown in Figure 13(A). The following explanation will mainly describe the differences from the case where the sample piece 4 is automatically sampled crosswise. Points that are not specifically explained are the same as in the case where the sample piece 4 is automatically sampled crosswise as described above.

[0109] As described above, when performing automatic planar sampling of the sample piece 4, the substage 22 is driven to a position where the rotation angle of the F axis is 0° and the rotation angle of the θ axis is 90°. Therefore, as shown in Figures 13(A) and 13(B), the surface of the base 50 of the carrier 5 is parallel to the xy plane and faces the z-axis+ side, and the pillar 53 protrudes toward the y-axis+ side. In other words, the surface of the base 50 of the carrier 5, i.e., the observation surface 40 of the sample piece 4, faces the ion beam column 11. In this state, the ion beam column 11 and the electron beam column 12 irradiate the carrier 5 with ion beam b11 and electron beam b12, respectively. The following processing is the same as when performing cross-sectional moving sampling of the sample piece 4.

[0110] Figure 14 is a flowchart illustrating the operation flow of the relocation process performed by the charged particle beam apparatus 10 when automatically sampling a sample piece 4 in a planar manner. Each process shown in Figure 14 is automatically executed and controlled by the integrated control unit 130. The processes described below are details of step S209, which is performed in the flowchart of Figure 10 described above.

[0111] The process in step S400 is the same as the process in step S300 in Figure 12. In step S401, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where the rotation angle of the F axis is 0° and the rotation angle of the θ axis is 90°. The processes from step S402 to step S407 are the same as the processes from step S302 to step S307 in Figure 12.

[0112] [Second action] The charged particle beam apparatus 10 performs a second operation as a fabrication and observation method, which includes preparation, processing, relocation, and finishing. In the second operation, the preparation, processing, and relocation are performed in the same way as in the first operation described above. During the relocation, attitude-controlled automatic microsampling may be performed to automatically control the orientation of the sample piece 4. Attitude-controlled automatic microsampling will be described in detail later.

[0113] In the finishing process, either the first method or the second method is performed. In the first method, one sampled sample piece 4 is subjected to finishing processing before another sample piece 4 is sampled from the wafer 3. In the second method, after all of the specified number of sample pieces 4 have been sampled from the wafer 3, each sample piece 4 is subjected to finishing processing. The processing of the charged particle beam apparatus 10 performing the second operation will be described below.

[0114] Figure 15 is a flowchart illustrating the processing of the charged particle beam apparatus 10 when the first method is performed in the finishing process. Each process shown in Figure 15 is automatically executed and controlled by the integrated control unit 130. Each process from step S501 to step S509 is the same as each process from step S201 to step S209 shown in Figure 10 above.

[0115] In step S510, the integrated control unit 130 controls the ion beam column 11, electron beam column 12, and substage 22 to process the sample piece 4 attached to the pillar 53 into a thin film with a thickness of, for example, 100 nm or less, for TEM observation. Details of the finishing process will be explained later.

[0116] In step S511, it is determined whether the specified number of sample pieces 4 have been formed and manufactured, transferred to the carrier 5, and given a finishing treatment. If each treatment has been performed on the specified number of sample pieces 4, the integrated control unit 130 makes a positive determination, and the process proceeds to step S512. If the number of sample pieces 4 that have undergone the above treatments has not reached the specified number, the integrated control unit 130 makes a negative determination, and the process returns to step S504. In step S512, the integrated control unit 130 performs the same process as in step S212 shown in Figure 10, and terminates each of the processes in the second operation.

[0117] Figure 16 is a flowchart illustrating the processing of the charged particle beam apparatus 10 when the second method is performed in the finishing process. Each process shown in Figure 16 is automatically executed and controlled by the integrated control unit 130. Each process from step S601 to step S609 is the same as the processes from step S201 to step S209 shown in Figure 10.

[0118] In step S610, it is determined whether the specified number of sample pieces 4 have been formed and manufactured and transferred to the carrier 5. If each process has been performed on the specified number of sample pieces 4, the integrated control unit 130 makes a positive determination, and the process proceeds to step S611. If the number of sample pieces 4 that have undergone the above processes has not reached the specified number, the integrated control unit 130 makes a negative determination, and the process returns to step S604.

[0119] In step S611, the integrated control unit 130 controls the ion beam column 11, electron beam column 12, and substage 22 to process each sample piece 4 attached to the pillar 53 to a thickness of, for example, 100 nm or less for TEM observation. Details of the finishing process will be explained later. In step S612, the integrated control unit 130 performs the same process as in step S212 shown in Figure 10, and completes each process of the second operation.

[0120] [Finishing process] Next, the details of the finishing process will be explained. Note that the following processes are performed in common during the finishing process, regardless of whether it is the first or second method. In the finishing process, the ion beam b11 is irradiated onto the observation surface 40 or the back surface of the observation surface 40 of the sample piece 4 by the ion beam column 11, thereby processing the sample piece 4 into a thin film of a desired thickness (for example, 100 nm or less). The charged particle beam apparatus 10 has a first process and a second process as finishing processes, and the finishing process is performed using either the first or second process. In the first process, the incident angle of the ion beam b11 irradiating the sample piece 4 is changed by performing the processing with the rotation angle of the F axis of the substage 22 controlled. In the second process, the rotation angle of the T axis of the substage 22 is controlled by controlling the rotation angle of the T axis of the wafer stage 21, thereby reducing the occurrence of the curtening effect on the sample piece 4. The first and second processes will be explained in detail below.

[0121] [First process] During the first finishing process, the substage controller 134 drives the substage 22 to a position where both the F-axis and θ-axis rotation angles are 90°, similar to the relocation process for the sample piece 4 described above during automatic cross-sectional sampling. That is, as shown in Figures 11(A) and 11(B), the surface of the base 50 of the carrier 5 is parallel to the zx plane and faces the y-axis+ side, with the pillar 53 protruding toward the z-axis+ side. The sample piece 4, which is bonded to the pillar 53 protruding toward the z-axis+ side, is irradiated with ion beam b11 from the z-axis+ side by the ion beam column 11, thereby performing finishing processing on the sample piece 4.

[0122] The surface of the sample piece 4 to be finished (observation surface 40) can be observed by the electron beam b12 because the substage 22 is driven (rotated) at a rotation angle of 90° on the θ axis. In other words, the processing state of the surface of the sample piece 4 to be finished is observed by imaging based on the electron beam b12 irradiated by the electron beam column 12. Prior to the finishing process, a processing frame is set on the sample piece 4 to identify the area to be finished. The sample piece 4 is abraded by irradiating this processing frame with the ion beam b11 from the ion beam column 11.

[0123] Figure 17 schematically shows the relationship between the ion beam b11 irradiated from the ion beam column 11 in the yz plane and the shape of the sample piece 4. Figure 17(A) shows the case where the substage 22 is driven to a position where the rotation angle of the F axis is 90°. In this case, the ion beam b11 is incident on the sample piece 4 perpendicular to the z-axis+ side of the sample piece 4. That is, the substage 22 is rotated and tilted around the F axis so that the optical axis OA1 of the ion beam b11 is parallel to the observation surface 40 of the sample piece 4. Rough thinning is performed on the observation surface 40 of the sample piece 4 by irradiation with the ion beam b11 (hereinafter referred to as the first finishing process).

[0124] Figure 17(B) schematically shows the shape of the sample piece 4 after the first finishing process. During the first finishing process, due to the energy distribution of the irradiated ion beam b11, the processed cross-section 41 formed by processing the observation surface 40 of the sample piece 4 is not parallel to the z axis, and a tilt occurs. For example, the z-axis- side of the processed cross-section 41 of the sample piece 4 protrudes more towards the y-axis- side than the z-axis- side.

[0125] The protruding portion of the processed cross-section 41 of the sample piece 4 is cut away to make the processed cross-section 41 of the sample piece 4 a vertical cross-section (hereinafter referred to as the second finishing process). When performing the second finishing process, the substage controller 134 drives the substage 22 so that the rotation angle of the F axis is changed to (90-α)°, without changing the rotation angle of the θ axis. α is an angle in the range of approximately 1° to 1.5°, and is set appropriately according to the size of the processed cross-section 41 of the sample piece 4 and beam conditions such as the beam intensity of the ion beam b11.

[0126] Figure 17(C) schematically shows the case where the rotation angle of the F axis is (90-α)°. As shown in the figure, the ion beam b11 is incident on the sample piece 4 at a non-perpendicular angle. That is, the angle of incidence of the ion beam b11 on the processed cross-section 41 of the sample piece 4 is adjusted by changing the inclination of the substage 22. As a result, the protruding portion on the z-axis side of the processed cross-section 41 of the sample piece 4 is removed by irradiation with the ion beam b11, and the sample piece 4 is processed to the finished cross-section 41a shown by the dashed line in Figure 17(C). This results in the formation of a finished cross-section 41a on the sample piece 4 with suppressed inclination.

[0127] Furthermore, during the second finishing process, the ion beam column controller 131 outputs ion beam b11 from the ion beam column 11 at a lower current than during the first finishing process. As a result, the beam intensity of ion beam b11 is lower than during the first finishing process, reducing the damage inflicted on the sample piece 4.

[0128] The processed cross-section 41 of the sample piece 4 is irradiated with electron beam b12 from the electron beam column 12, thereby imaging the processed cross-section 41 and observing the processing state of the observation surface 40. Based on the observation, the integrated control unit 130 stops the second finishing process when the processed cross-section 41 becomes the desired shape, which is the finished cross-section 41a. The observation may be performed by the user checking the generated image, or by the integrated control unit 130 comparing the image of the processed cross-section 41 with a template image in which the desired shape, the finished cross-section 41a, is imaged.

[0129] Next, the back surface 42 of the sample piece 4 is subjected to finishing (hereinafter referred to as the third finishing process). When performing the third finishing process, the substage controller 134 rotates the substage 22 180° around the θ axis from the state during the second finishing process, driving it to a position where the rotation angle of the θ axis is -90°. The surface of the sample piece 4 to be finished (the back surface 42 of the observation surface 40) can be observed by the electron beam b12 because the substage 22 is driven (rotated) to a position where the rotation angle of the θ axis is -90°. In other words, the processing state of the back surface 42 of the sample piece 4 is observed by imaging based on the electron beam b12 irradiated by the electron beam column 12.

[0130] Furthermore, the substage controller 134 drives the substage 22 to a position where the rotation angle of the F axis is (90+α)°. The value of α is the same as that during the second finishing process. In this state, the ion beam column 11 irradiates the back surface 42 of the sample piece 4 with ion beam b11. As a result, the back surface 42 of the sample piece 4 is also processed into a vertical cross-sectional shape without inclination. That is, by changing the inclination of the substage 22, the incidence angle of the ion beam b11 on the back surface 42 of the sample piece 4 is adjusted, and the finished cross-section 41a and the back surface 42 of the sample piece 4 are processed in parallel. In the third finishing process as well, the back surface 42 of the sample piece 4 is irradiated with electron beam b12 from the electron beam column 12, so that the back surface 42 is imaged and observed. Based on the observation results, the integrated control unit 130 stops the third finishing process when the back surface 42 has reached the desired shape. In this case as well, observation may be performed by the user confirming the image, or by the integrated control unit 130 comparing the template image with the generated image.

[0131] The sample piece 4 is thinned by the second and third finishing processes described above. Furthermore, the sample piece 4 that has undergone the second and third finishing processes may be cleaned using a low-acceleration ion beam.

[0132] Figure 18 is a flowchart illustrating the operation flow of the first finishing process performed by the charged particle beam apparatus 10. Each process shown in Figure 18 is automatically executed and controlled by the integrated control unit 130. The processes described below are details of step S510 in Figure 15 or step S611 in Figure 16. That is, the processes described below are performed after the sample piece 4 has been transferred to the pillar 53 of the carrier 5.

[0133] In step S701, the integrated control unit 130 controls the wafer stage controller 133 to move the x-base 210, y-base 211, and z-base 212 in the xy plane, moving the substage 22 below the ion beam column 11 and electron beam column 12 (towards the z-axis). Note that if the finishing process is performed using the first method, that is, if the process shown in Figure 15 is performed, the process in step S701 is not performed.

[0134] In step S702, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where both the rotation angles of the F axis and the θ axis are 90°. In step S703, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the sample piece 4 with ion beam b11 from the ion beam column 11. Similarly, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the sample piece 4 with electron beam b12 from the electron beam column 12. The integrated control unit 130 recognizes the position of the sample piece 4 using the image (sample piece position image) generated by the detector controller 136 based on the detection signal detected by the charged particle detector 109, and identifies the position of the sample piece 4 to be finished.

[0135] In step S704, the integrated control unit 130 sets a processing frame on the observation surface 40 of the sample piece 4 based on the position identified using the sample piece position image. In step S705, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the processing frame set on the observation surface 40 of the sample piece 4 with ion beam b11 from the ion beam column 11. This performs the first finishing process.

[0136] In step S706, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where the rotation angle of the F axis is (90-α)°. In step S707, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the processed surface 41 of the sample piece 4 with ion beam b11 from the ion beam column 11. This performs the second finishing process. At this time, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the processed surface 41 of the sample piece 4 with electron beam b12 from the electron beam column 12. The integrated control unit 130 images the processed surface 41 of the sample piece 4 using an image generated by the detector controller 136 based on the detection signal detected by the charged particle detector 109.

[0137] The integrated control unit 130 determines, for example, whether the processed cross-section 41 of the sample piece 4 has been processed to the desired shape, i.e., the shape of the finished cross-section 41a, by comparing the generated image with a template image, etc. If the integrated control unit 130 determines that the processed cross-section 41 of the sample piece 4 has been processed to the shape of the finished cross-section 41a, it controls the ion beam column controller 131 and the electron beam column controller 132 to stop the irradiation of ion beam b11 from the ion beam column 11 and the irradiation of electron beam b12 from the electron beam column 12.

[0138] In step 708, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where the rotation angle of the θ axis is -90° and the rotation angle of the F axis is (90+α)°. In step S709, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the back surface 42 of the sample piece 4 with ion beam b11 from the ion beam column 11. This performs the third finishing process.

[0139] In this case as well, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the back surface 42 of the sample piece 4 with electron beam b12 from the electron beam column 12. The integrated control unit 130 images the back surface 42 of the sample piece 4 using the image generated by the detector controller 136 based on the detection signal detected by the charged particle detector 109. In the same manner as in step S707, the integrated control unit 130 terminates the third finishing process when it determines that the back surface 42 of the sample piece 4 has been processed into the desired shape based on the generated image. That is, the integrated control unit 130 controls the ion beam column controller 131 and the electron beam column controller 132 to stop the irradiation of ion beam b11 from the ion beam column 11 and the irradiation of electron beam b12 from the electron beam column 12, thereby terminating the finishing process.

[0140] [Second process] In the second finishing process, the sample piece 4 is processed in such a way that the occurrence of the curtaining effect is reduced, as described above. The curtaining effect is the unevenness in the degree to which the sample piece 4 is abraded by the ion beam b11 irradiated by the ion beam column 11.

[0141] Figure 19 schematically shows the appearance of the observation surface 40 of the sample piece 4. Figure 19(A) shows the state in which the curtaining effect has not occurred, and Figure 19(B) shows the state in which the curtaining effect has occurred. The curtaining effect occurs due to the material and shape of the outermost surface 49 side of the sample piece 4 being processed, that is, the z-axis+ side of the sample piece 4 that has been moved to the carrier 5 mounted on the substage 22. For example, if there is a structure made of a hard material on the outermost surface 49 side of the sample piece 4, processing (cutting) by the ion beam b11 irradiated from the ion beam column 11 will not progress easily on the bottom surface 47 side (z- side) of that structure 400. Also, if there is a structure 401 made of an easily processable material on the outermost surface 49 side of the sample piece 4, processing (cutting) by the ion beam b11 will progress easily. As a result, streaky processing irregularities 44, 45 occur in the processed cross-section 41 of the sample piece 4. This processing inconsistency, which is due to variations in the thickness of sample piece 4, will interfere with subsequent TEM observation.

[0142] In the second process, in order to suppress the curtaining effect, the sample piece 4 is rotated in the in-plane direction of the processed cross-section 41, and the processed cross-section 41 of the sample piece 4 is processed. This will be explained in detail below. In the second process as well, the processing up to the first finishing process is the same as the processing performed in the first process described above.

[0143] Figure 20 schematically shows the holder 6, carrier 5, and sample piece 4 during the second finishing process. Figure 20(A) schematically shows the holder 6, carrier 5, and sample piece 4 as viewed from the z-axis+ side. Figure 20(B) schematically shows a magnified view of the appearance of the pillar 53 of the carrier 5 mounted on the holder 6 and the sample piece 4 as viewed from the x-axis- side.

[0144] During the second finishing process, the substage controller 134 drives the substage 22 to a position where the rotation angle of the θ axis is 0°. That is, the substage 22 rotates so that the processed cross-section 41 formed by processing from the observation surface 40 of the sample piece 4 intersects with the T axis, which is the tilt axis of the wafer stage 21 set parallel to the x axis. As a result, the side surface of the pillar 53 of the carrier 5 becomes parallel to the zx plane and faces the electron beam column 12. Also, as in the first process, the substage controller 134 drives the substage 22 to a position where the rotation angle of the F axis is (90+α)°.

[0145] Furthermore, the wafer stage controller 133 drives the wafer stage 21 to a position where the rotation angle of the T-axis of the wafer stage 21 is 10°. As a result, the sub-stage 22 provided on the z-base 212 is tilted 10° with respect to the xy-plane. Note that the rotation angle of the T-axis is not limited to 10°, and can be automatically or manually set to a suitable value depending on the shape and size of the structures 400, 401 of the sample piece 4.

[0146] In this state, the ion beam column 11 irradiates the sample piece 4 with ion beam b11. Since the rotation angle of the F axis of the substage 22 is (90+α)°, the ion beam b11 is incident non-perpendicular to the processed surface 41 of the sample piece 4, similar to the first treatment. As a result, the protruding portion on the z-axis side of the processed surface 41 of the sample piece 4 is removed by irradiation with ion beam b11, forming a perpendicular finished surface 41a.

[0147] Furthermore, the rotation angle of the T-axis is 10°. That is, as shown in Figure 20(B), the wafer stage 21 rotates around the T-axis parallel to the x-axis and tilts with respect to the xy-plane, so that the incident angle of the ion beam b11 from the observation surface 40 of the sample piece 4 to the processed cross-section 41 changes. The ion beam b11 with a changed incident angle avoids the structures 400 and 401 on the outermost surface 49 side of the sample piece 4 and irradiates the bottom surface 47 side of the structures 400 and 401. As a result, the occurrence of processing irregularities 44 and 45 caused by the structures 400 and 401 on the outermost surface 49 side of the sample piece 4 is suppressed. During the second finishing process, the ion beam column controller 131 outputs the ion beam b11 from the ion beam column 11 at a lower current than during the first finishing process.

[0148] Subsequently, the substage controller 134 drives the substage 22 to a position where both the rotation angles of the F axis and the θ axis are 90°. The wafer stage controller 133 drives the wafer stage 21 to a position where the rotation angle of the T axis is 0°, so that the inclination of the substage 22, which is provided on the z base 212, with respect to the xy plane is 0°. That is, the substage 22 is in the position shown in Figures 11(A) and 11(B). As a result, the processed cross-section 41 of the sample piece 4 bonded to the pillar 53 faces the electron beam column 12. In this state, the processed cross-section 41 of the sample piece 4 is irradiated with electron beam b12 from the electron beam column 12, so that the processed cross-section 41 is imaged and the processing state is observed. As a result of the observation, the integrated control unit 130 stops the second finishing process when the processed cross-section 41 has reached the desired shape of the finished cross-section 41a.

[0149] Next, a third finishing process is performed on the back surface 42 of the sample piece 4. During the third finishing process, as in the first process, the substage controller 134 drives the substage 22 to a position where the rotation angle of the F axis is (90-α)°. As in the second finishing process, the substage controller 134 drives the substage 22 to a position where the rotation angle of the θ axis is 0°, so that the side surface of the pillar 53 of the carrier 5 is parallel to the zx plane and faces the electron beam column 12. Furthermore, the wafer stage controller 133 drives the wafer stage 21 to a position where the rotation angle of the T axis is 10°, so that the substage 22 provided on the z base 212 is tilted by 10° with respect to the xy plane.

[0150] The ion beam column 11 irradiates the back surface 42 of the sample piece 4 with ion beam b11. Since the rotation angle of the F axis of the substage 22 is (90-α)° and the rotation angle of the T axis is 10°, the back surface 42 of the sample piece 4 is processed into a vertical cross section while suppressing the occurrence of the curtaining effect. In other words, by changing the inclination of the substage 22, the incidence angle of the ion beam b11 on the back surface 42 of the sample piece 4 is adjusted, and the finished cross section 41a and the back surface 42 of the sample piece 4 are processed in parallel.

[0151] Subsequently, the substage controller 134 drives the substage 22 to positions where the rotation angles of the F-axis and θ-axis are 90° and -90°, respectively. The wafer stage controller 133 drives the wafer stage 21 to a position where the rotation angle of the T-axis is 0°, thereby changing the inclination of the substage 22, which is provided on the z-base 212, with respect to the xy-plane to 0°.

[0152] As the substage 22 moves as described above, the back surface 42 of the sample piece 4, which is attached to the pillar 53, faces the electron beam column 12. In this state, the electron beam b12 from the electron beam column 12 irradiates the back surface 42 of the sample piece 4, imaging the back surface 42 and allowing observation of the processing state. Based on the observation, the integrated control unit 130 stops the third finishing process when the back surface 42 has reached the desired shape. Through the second process described above, a thin film is formed in which the observation surface 40 and the back surface 42 of the sample piece 4 are parallel to each other, with the occurrence of the curtaining effect suppressed.

[0153] Figure 21 is a flowchart illustrating the operation flow of the second finishing process performed by the charged particle beam apparatus 10. Each process shown in Figure 21 is automatically executed and controlled by the integrated control unit 130. The processes described below are details of step S510 in Figure 15 or step S611 in Figure 16. That is, the processes described below are performed after the sample piece 4 has been transferred to the pillar 53 of the carrier 5.

[0154] Each process from step S801 to step S805 is the same as each process from step S701 to step S705 in Figure 18. In step S806, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where the rotation angle of the F axis is (90+α)° and the angle of the θ axis is 0°. The integrated control unit 130 controls the wafer stage controller 133 to drive the wafer stage 21 to a position where the rotation angle of the T axis is 10°, thereby changing the inclination of the substage 22 provided on the z base 212 with respect to the xy plane to 10°.

[0155] In step S807, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the processed cross-section 41 of the sample piece 4 with ion beam b11 from the ion beam column 11. This performs the second finishing process. In step S808, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where both the rotation angles of the F axis and the θ axis are 90°. The integrated control unit 130 controls the wafer stage controller 133 to drive the wafer stage 21 to a position where the rotation angle of the T axis is 0°, changing the inclination of the substage 22 with respect to the xy plane to 0°.

[0156] In step S809, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the processed cross-section 41 of the sample piece 4 with electron beam b12 from the electron beam column 12. The integrated control unit 130 images the processed cross-section 41 of the sample piece 4 using an image generated by the detector controller 136 based on the detection signal detected by the charged particle detector 109. The integrated control unit 130 determines whether the processed cross-section 41 (i.e., observation surface 40) of the sample piece 4 has been processed to the shape of the finished cross-section 41a by, for example, comparing the generated image with a template image. If the integrated control unit 130 determines that the sample piece 4 has been processed to the shape of the finished cross-section 41a, it controls the electron beam column controller 132 to stop the irradiation of electron beam b12 from the electron beam column 12.

[0157] In step S810, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where the rotation angle of the F axis is (90-α)° and the rotation angle of the θ axis is 0°. The integrated control unit 130 also controls the wafer stage controller 133 to drive the wafer stage 21 to a position where the rotation angle of the T axis is 10°, thereby changing the inclination of the substage 22 with respect to the xy plane to 10°.

[0158] In step S811, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the back surface 42 of the sample piece 4 with ion beam b11 from the ion beam column 11. This performs the third finishing process. In step S812, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where the rotation angle of the F axis of the substage 22 is 90° and the rotation angle of the θ axis is -90°. The integrated control unit 130 controls the wafer stage controller 133 to drive the wafer stage 21 to a position where the rotation angle of the T axis is 0°, thereby changing the inclination of the substage 22 with respect to the xy plane to 0°.

[0159] In step S813, the integrated control unit 130 controls the electron beam column controller 132 to irradiate the back surface 42 of the sample piece 4 with electron beam b12 from the electron beam column 12. The integrated control unit 130 images the back surface 42 of the sample piece 4 using an image generated by the detector controller 136 based on the detection signal detected by the charged particle detector 109. In the same manner as in step S809, the integrated control unit 130 terminates the finishing process when it determines that the desired shape has been processed on the back surface 42 of the sample piece 4 based on the generated image. That is, the integrated control unit 130 controls the electron beam column controller 132 to stop the irradiation of electron beam b12 from the electron beam column 12.

[0160] [Automatic Microsampling for Posture Control] Next, we will explain the relocation process when the orientation of the sample piece 4 is automatically controlled (orientation-controlled automatic microsampling). Orientation-controlled automatic microsampling is a technique that changes the orientation of the sample piece 4 and performs microsampling by controlling the rotation direction of the wafer stage 21 (i.e., the angle of the R axis) when sampling the sample piece 4 from the wafer 3, and the rotation angle of the needle 112 after sampling. The orientation of the carrier 5, to which the sample piece 4 sampled by orientation-controlled automatic microsampling is relocated, changes in accordance with the change in the orientation of the sample piece 4. As a result, the orientation of the sample piece 4 relocated to the pillar 53 will be different from the orientation it was in when it was extracted from the wafer 3.

[0161] The following explanation uses the example of transferring a sample piece 4 sampled from wafer 3 to pillar 53 with its vertical orientation reversed. That is, the sample piece 4 is transferred so that its outermost surface 49 faces the straight section 51 of the base 50 of carrier 5.

[0162] Figure 22 schematically shows the positional relationship between the sample piece 4 and the needle 112 when the sample piece 4 is sampled from the wafer 3. Figure 22(A) is a view of the sample piece 4 and the needle 112 from the z-axis+ side, and Figure 22(B) is a view of the sample piece 4 and the needle 112 from the observation surface 40 side of the sample piece 4. When the needle 112 is brought close to the sample piece 4, the wafer stage controller 133 rotates the rotation base 213 by approximately 35° around the R axis. Furthermore, the angle β that the needle 112 makes with respect to the surface of the wafer 3, i.e., the xy plane (approach angle), when the sample piece 4 is sampled from the wafer 3 is assumed to be 30°.

[0163] Furthermore, the substage controller 134 drives the substage 22 to a position where the rotation angle of the F axis is 0° and the rotation angle of the θ axis is 54.7°. As a result, the surface of the base 50 of the carrier 5, which is mounted on the holder 6 attached to the substage 22, is parallel to the xy plane and faces the z-axis+ side.

[0164] Figure 23(A) is a view of the substage 22, holder 6, and carrier 5 from the z-axis+ side when the substage 22 has been moved as described above. Figure 23(B) is a view of the pillar 53 of the carrier 5 and the sample piece 4 being approached by the pillar 53 from the z-axis+ side in Figure 23(A). Because the rotation angle of the substage 22 along the θ axis is 54.7°, the pillar 53 of the carrier 5 extends at an angle of 54.7° with respect to the x axis. The side surface 48 of the sample piece 4 is adhered to this pillar 53 with the outermost surface 49 of the sample piece 4 facing the base 50 of the carrier 5.

[0165] Specifically, after the sample piece 4 is lifted out from the wafer 3, the needle controller 142 rotates the needle 112, which is bonded to the sample piece 4, by approximately 110°. As a result, as shown in Figure 23(B), the side surface 48 of the sample piece 4 on the side where the needle 112 is not bonded faces the pillar 53, and the outermost surface 49 of the sample piece 4 faces the base 50 of the carrier 5.

[0166] After the orientation of the sample piece 4 relative to the carrier 5 is as shown in Figure 23(B), the needle controller 142 moves the needle 112 to a position where the sample piece 4 can be adhered to the pillar 53. Thereafter, the same process as the relocation process described above is performed to adhere the sample piece 4 to the pillar 53 and cut the needle 112 from the sample piece 4.

[0167] As described above, the rotation angles of the F-axis and θ-axis of the substage 22 are set for the relocated sample piece 4, and the ion beam b11 is irradiated from the ion beam column 11, similar to the finishing process described above. That is, the finishing process is performed with the bottom surface 47 of the sample piece 4 relocated to the pillar 53 positioned on the z-axis+ side. Generally, when finishing is performed by FIB, the surface of the sample piece 4 that is irradiated by the ion beam b11, i.e., the surface of the sample piece 4 located on the z-axis+ side during the finishing process, is the most likely to be removed. For this reason, the surface of the sample piece 4 located on the z-axis+ side may become extremely thin or disappear. If there is a structure to be observed near the outermost surface 49 of the sample piece 4, and the outermost surface 49 of the sample piece 4 is finished facing the z-axis- side by the above attitude-controlled automatic microsampling, the disappearance of the structure to be observed near the outermost surface 49 during the finishing process is suppressed.

[0168] Figure 24 is a flowchart illustrating the operation flow of the relocation process performed by the charged particle beam apparatus 10 when performing attitude-controlled automatic microsampling of the sample piece 4. Each process shown in Figure 24 is automatically executed and controlled by the integrated control unit 130. The processes described below are details of steps S506 to S509 in Figure 15, or steps S606 to S609 in Figure 17.

[0169] In step S901, the integrated control unit 130 controls the wafer stage controller 133 to rotate the rotary base 213 about 35° around the R axis. In step S902, the integrated control unit 130 controls the needle controller 142 to set the approach angle β of the needle 112 to 30°. Then, the integrated control unit 130 controls the needle controller 142 to move the needle 112 closer to the sample piece 4. The integrated control unit 130 performs deposition processing to adhere the sample piece 4 to the tip of the needle 112.

[0170] In step S903, the integrated control unit 130 controls the ion beam column controller 131 to irradiate the connection point 4a (see Figure 8) where the sample piece 4 and wafer 3 are connected with the ion beam column 11 with the ion beam b 11, thereby separating the sample piece 4 from the wafer 3. In step S904, the integrated control unit 130 controls the needle controller 142 to lift out the sample piece 4 that has been separated from the wafer 3 and rotate the needle 112 by approximately 110°. In step S905, the integrated control unit 130 controls the wafer stage controller 133 to move the x base 210, y base 211, and z base 212 in the xy plane, moving the substage 22 below the ion beam column 11 and electron beam column 12 (towards the z axis).

[0171] In step S906, the integrated control unit 130 controls the substage controller 134 to drive the substage 22 to a position where the rotation angle of the F axis is 0° and the rotation angle of the θ axis is 54.7°. Each process from step S907 to step S912 is the same as each process from step S302 to step S307 in Figure 12.

[0172] Furthermore, the approach angle β is not limited to 30°, but can be set to a suitable value depending on the shape and size of the sample piece 4. Also, depending on the value of the approach angle β, the rotation angle of the R axis of the rotating base 213, the rotation angle of the needle 112, and the rotation angle of the θ axis of the substage 22 will be different from the values ​​mentioned above.

[0173] [Third action] As a third operation, the charged particle beam apparatus 10 performs the preparation process, processing process, and relocation process described above. In other words, in the case of the third operation, the observation process in the first operation and the finishing process in the second operation are not performed, and only sampling of the sample piece 4 is carried out.

[0174] In this case, the integrated control unit 130 executes the processes shown in the flowchart of Figure 10, from steps S201 to S209, S211, and S212.

[0175] The holder 6, to which the carrier 5 into which the sample piece 4 has been moved by the first, second, or third operation described above is attached, is transported to the sample piece observation device 30 by the transport mechanism 90. Then, the TEM device equipped in the sample piece observation device 30 performs cross-sectional or planar observation using TEM images. According to the embodiments described above, at least one of the following effects can be obtained.

[0176] (1) The charged particle beam apparatus 10 includes a wafer stage 21 on which a wafer 3 is placed and moved, a needle 112 that holds the sample pieces 4 separated and extracted from the wafer 3 and transports them to a plurality of carriers 5 mounted on a holder 6, and a substage 22 to which the holder 6 is detachably attached and which moves independently of the wafer stage 21. This allows the orientation of the plurality of carriers 5 mounted on the holder 6 to be controlled independently of the wafer stage 21 so as to be different from the orientation of the wafer 3, thereby increasing the number of sample pieces 4 that can be moved to the carriers 5 and improving the efficiency of transferring the sample pieces 4.

[0177] Furthermore, since the holder 6 is detachably attached to the substage 22, only the holder 6 removed from the substage 22 is transported. Compared to conventional technology in which the wafer stage and holder are transported together, this eliminates the need for a large transport mechanism and makes it easier to transport the sample piece 4. Also, in conventional technology in which the wafer stage and holder are transported together, if the wafer stage is miniaturized to reduce the difficulty of transport, it becomes necessary to limit the size of the wafer that can be placed on the wafer stage. In contrast, in this embodiment, since only the holder 6 is transported, there is no need to miniaturize the wafer stage 21, and it is possible to suppress limitations on the size of the wafer 3 that can be placed on the wafer stage 21.

[0178] (2) The substage 22 is mounted on the z-base 212 and is tilted about a θ-axis extending in a direction intersecting the z-base 212 and an F-axis extending in a direction intersecting the θ-axis. This makes it possible to control the orientation of the substage 22 independently of the wafer stage 21 using two axes.

[0179] (3) The substage 22 has a tilting mechanism 223 that tilts the holder 6. The holder 6 is equipped with multiple carriers 5 and can be attached to and detached from the substage 22 independently of the tilting mechanism 223. This makes it possible to control the posture of the holder 6 which is attached to the substage 22. In addition, it is possible to transport only the holder 6 by the transport mechanism 90.

[0180] (4) The charged particle beam apparatus 10 performs a first operation as a method for preparing and observing the sample piece 4, which includes a processing process, a transfer process, and an observation process. In the processing process, the wafer 3 is irradiated with an ion beam b11, and a sample piece 4 is processed so that the plane or cross-section of the wafer 3 becomes the observation surface 40. In the transfer process, a needle 112 is attached to the processed sample piece 4 and it is extracted and separated from the wafer 3. The sample piece 4 is mounted on a carrier 5 on a holder 6 mounted on a substage 22 that can be tilted and rotated, so that the observation surface 40 is parallel to the surface of the carrier 5. In the observation process, the substage 22 is rotated so that the observation surface 40 of the sample piece 4 and the back surface 42 of the observation surface 40 can be observed with the electron beam b12. As a result, the orientation of the substage 22 is controlled independently of the wafer stage 21, making it easier to control the orientation when transferring the lifted sample piece 4 to the carrier 5 and when observing the sample piece 4 transferred to the carrier 5, thereby improving the efficiency of the transfer and observation processes.

[0181] (5) The charged particle beam apparatus 10 performs a second operation as a method for preparing and observing the sample piece 4, which includes a processing process, a relocation process, and a first finishing process. In the first finishing process, the observation surface 40 or back surface 42 of the sample piece 4 is processed by irradiation with the ion beam b11, and the sample piece 4 is made into a thin film. The substage 22 is rotated around the F axis so that the observation surface 40 and the back surface 42 are processed in parallel, thereby changing the inclination of the substage 22 and adjusting the incidence angle of the ion beam b11 on the observation surface 40 or back surface 42. The electron beam b12 is irradiated onto the observation surface 40 or back surface 42 that is being processed by the ion beam b11, and the processing state of the observation surface 40 or back surface 42 is observed. As a result, the attitude of the substage 22 is controlled independently of the wafer stage 21, making it easier to control the attitude of the sample piece 4 during the finishing process and improving the efficiency of the finishing process.

[0182] (6) The charged particle beam apparatus 10 performs a second operation as a method for preparing and observing the sample piece 4, which includes a processing process, a relocation process, and a second finishing process. In the second finishing process, the substage 22 is tilted around the F axis so that the observation surface 40 of the sample piece 4 is parallel to the optical axis OA1 of the ion beam b11. The substage 22 is rotated around the θ axis so that the observation surface 40 intersects with the T axis, which is the tilt axis of the wafer stage 21. The wafer stage 21 is tilted around the T axis so that the angle of incidence of the ion beam b11 to the observation surface 40 of the sample piece 4 changes. The observation surface 40 or the back surface 42 of the sample piece 4 is processed by irradiation with the ion beam b11, and the sample piece 4 is made into a thin film. The tilt of the substage 22 is changed by rotating the substage 22 around the F axis so that the observation surface 40 and the back surface 42 are processed in parallel, and the angle of incidence of the ion beam b11 to the observation surface 40 or the back surface 42 is adjusted. The substage 22 is rotated around the θ axis so that the observation surface 40 or back surface 42 being processed by the ion beam b11 can be observed by irradiation with the electron beam b12, thereby allowing observation of the processing state of the observation surface 40 or back surface 42. As a result, the substage 22 tilts around the T axis, causing the angle of incidence of the ion beam b11 to the observation surface 40 of the sample piece 4 to change within the plane of the observation surface 40, thus enabling a finishing process that suppresses the occurrence of the curtaining effect.

[0183] Although embodiments of this disclosure have been specifically described above, the invention is not limited to the embodiments described above, and various modifications are possible without departing from the gist of the invention. Each embodiment allows for the addition, deletion, and replacement of components, except for essential components. Unless otherwise specified, each component may be singular or plural. Combinations of each embodiment are also possible. [Explanation of symbols]

[0184] 1 Inspection system, 3 Wafer, 4 Sample piece, 5 Carrier, 6 Holder, 10 Charged particle beam apparatus, 11 Ion beam column, 12 Electron beam column, 21 Wafer stage, 22 Substage, 40 Observation surface, 41 Processing cross section, 42 Back surface, 112 Needle, 130 Integrated control unit, 210 x-base, 211 y-base, 212 z-base 213 Rotating base, 214 Support mechanism, 221 Mounting part, 222 Mounting support part, 223 Tilt mechanism

Claims

1. A charged particle beam apparatus for preparing sample pieces from a wafer using a charged particle beam, A charged particle beam tube that irradiates the charged particle beam, A wafer stage on which the wafer is placed and moved, A sample transfer mechanism that holds the sample piece separated and extracted from the wafer and transports it to a plurality of carriers mounted on a sample piece holder, A charged particle beam apparatus comprising: a sample holder stage, which is detachably mounted on the wafer stage and moves independently of the wafer stage; and a sample holder stage provided on the wafer stage.

2. In the charged particle beam apparatus according to claim 1, The wafer stage is An X-base that moves in the first direction, A Y-base is provided on the X-base, is movable in the first direction together with the X-base, and is movable in a second direction intersecting the first direction, A Z-base is provided on the Y-base, is movable in the first direction together with the X-base and the Y-base, is movable in the second direction together with the Y-base, and is movable in a third direction intersecting the first and second directions. A rotating base is provided on the Z-base, on which the wafer is placed, and which rotates about a first axis extending in a direction intersecting the Z-base, The device has a support mechanism that supports the X base, Y base, Z base, and rotating base so that they can rotate around a second axis extending in a direction intersecting the first axis, The stage for the sample holder is mounted on the Z-base and is inclined around a third axis extending in a direction intersecting the Z-base and a fourth axis extending in a direction intersecting the third axis, in a charged particle beam apparatus.

3. In the charged particle beam apparatus according to claim 1, The sample holder stage has a tilting mechanism for tilting the sample holder, The charged particle beam apparatus comprises a sample holder that is equipped with multiple carriers and is detachable from the sample holder stage independently of the tilting mechanism.

4. A method for preparing and observing sample pieces, An ion beam is irradiated onto a wafer placed on a wafer stage, and the sample piece is processed so that the plane or cross-section of the wafer is used as the observation surface. A sample transfer mechanism is attached to the processed sample piece to extract and separate it from the wafer. The sample piece is mounted on a carrier on a sample piece holder, which is detachably attached to a sample piece holder stage provided on the wafer stage and capable of tilting and rotating relative to the wafer stage, such that the observation surface is parallel to the surface of the carrier. The stage for the sample holder is rotated so that the observation surface of the sample piece can be observed with an electron beam. A method for preparing and observing a sample piece, comprising rotating a sample piece holder stage so that the back surface of the observation surface of the sample piece can be observed with the electron beam.

5. A method for preparing and observing sample pieces, An ion beam is irradiated onto a wafer placed on a wafer stage, and the sample piece is processed so that the plane or cross-section of the wafer is used as the observation surface. A sample transfer mechanism is attached to the processed sample piece to extract and separate it from the wafer. The sample piece is mounted on a carrier on a sample piece holder, which is detachably attached to a sample piece holder stage provided on the wafer stage and capable of tilting and rotating relative to the wafer stage, such that the observation surface is parallel to the surface of the carrier. The sample holder stage is tilted so that the observation surface is parallel to the optical axis of the ion beam. The sample holder stage is rotated so that the observation surface or the back surface of the observation surface can be observed with an electron beam. The observation surface or the back surface of the sample piece is processed by irradiation with the ion beam to thin the sample piece. The inclination of the sample holder stage is changed to adjust the incidence angle of the ion beam onto the observation surface or the back surface so that the observation surface and the back surface are machined in parallel. A method for preparing and observing a sample piece, comprising irradiating the observation surface or the back surface, which has been processed by the ion beam, with the electron beam to observe the processing state of the observation surface or the back surface.

6. A method for preparing and observing sample pieces, An ion beam is irradiated onto a wafer placed on a wafer stage, and the sample piece is processed so that the plane or cross-section of the wafer is used as the observation surface. By attaching a sample transfer mechanism to the processed sample piece, it is extracted and separated from the wafer. The sample piece is mounted on a carrier on a sample piece holder, which is detachably attached to a sample piece holder stage provided on the wafer stage and capable of tilting and rotating relative to the wafer stage, such that the observation surface is parallel to the surface of the carrier. The sample holder stage is tilted so that the observation surface is parallel to the optical axis of the ion beam. The sample piece holder stage is rotated so that the inclination axis of the stage on which the sample piece holder stage is mounted intersects with the observation surface. The stage is tilted around the tilt axis so that the angle of incidence of the ion beam with respect to the observation surface changes. The observation surface or the back surface of the sample piece is processed by irradiation with the ion beam to thin the sample piece. The inclination of the sample holder stage is changed to adjust the incidence angle of the ion beam onto the observation surface or the back surface so that the observation surface and the back surface are machined in parallel. A method for preparing and observing a sample piece, comprising rotating the sample piece holder stage so that the observation surface or the back surface processed by the ion beam becomes observable by irradiation with an electron beam, thereby observing the processing state of the observation surface or the back surface.

7. In the charged particle beam apparatus according to claim 1, A charged particle beam apparatus comprising a transport mechanism for transporting the sample holder on which multiple carriers are attached.

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