JP4521247B2 - Sample table for charged particle beam equipment - Google Patents

Description

  The present invention relates to a sample stage for a charged particle beam apparatus such as a scanning electron microscope (SEM) or a focused ion beam (FIB) processing observation apparatus, and more particularly to a sample stage using a sample exchange rod. The present invention relates to a sample stage for a charged particle beam apparatus of a type in which is set in a sample chamber.

Various types of sample platforms are used in charged particle beam devices that perform observation and processing of samples using charged particle beams (electron beams, ion beams) such as scanning electron microscopes and focused ion beam processing observation devices.
(Stage holding sample) is used. Such a sample stage is usually provided with a mechanism for tilting the angle (θ direction) in addition to the two-dimensional movement in the X-axis and Y-axis directions in order to change the observation site of the sample. However, the moving angle of the θ-direction moving mechanism is limited by the stage mechanism. Therefore, when it is necessary to observe or process the sample at an angle greater than the tilt angle of the stage, remove the sample from the inside of the device, remove it from the sample table, reattach it to the sample table with the desired inclined surface, and re-install it inside the device. When the sample is introduced for observation or when a special sample stage as described in JP-A No. 2002-319362 is used and observation is to be performed at a high angle tilt greater than the tilt angle of the stage mechanism, the sample is the same as above. It was necessary to remove the sample from the inside of the apparatus, remove the sample table from the sample holder, rotate it 90 °, and reattach it. The same applies to the case where a cross section of a sample is prepared with a focused ion beam processing observation apparatus and then the cross section is observed with a scanning electron microscope. Furthermore, a focused ion beam processing observation device and a scanning transmission electron microscope (Scanning)
Transmission Electron Microscope (STEM) or FIB-STEM and FIB-SEM in which a scanning electron microscope is integrated have different processing surfaces and observation surfaces.

JP 2002-319362 A

  The reattachment of the sample as described above has a problem that the observation efficiency is lowered because a certain work time is required. In addition, sample contamination and damage could occur. Microscopic observation samples were often very small, and there was a possibility of sample loss.

  An object of the present invention is to provide a sample stage provided with a mechanism capable of tilting a sample at a high angle in the apparatus without detaching the sample and the sample stage.

  The configuration of the present invention for achieving the above object is as follows.

A movable member for placing the sample; a rail part for moving the movable member along a predetermined path; a rail holding part for holding the rail part; an attachment part for attaching the rail holding part to the sample stage; And a receiving hole for attaching an extrusion member that pushes out the movable member from the outside for moving the movable member along the rail, and the rail portion is a groove provided in the rail holding portion. And a protrusion that fits into the groove is provided on the movable member, and the movable member is composed of two or more components through a bendable connecting portion, and each of the components is the protrusion. A charged particle beam apparatus sample stage , wherein the rail holding portion includes at least two different rail portions corresponding to the constituent members .

  The movable member may have any shape as long as the sample can be mounted, but a flat plate has the simplest structure and is low in cost. Since the size is enough to enter the sample chamber of the electron microscope, the size of the movable member should be 20 mm square or less.

  The rail has a groove, and a structure in which a guide ball is attached to the movable part and fits in the groove is simple and highly reliable. However, not limited to this, the movable member moves on a predetermined rail. Any structure may be used as long as it has a simple structure. The extruding member is simple and low-cost, so-called sample exchange rod that can move the sample stage to the sample chamber of the microscope and fix it to the sample stage in the sample chamber, but it has the function of simply moving the movable member It doesn't matter.

  It is possible to tilt the sample up to an angle exceeding the tilt angle limit of the apparatus. Accordingly, it is not necessary to take out the sample outside the apparatus, and it is possible to improve work efficiency and reduce contamination and destruction of the sample.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a configuration of a typical scanning electron microscope in a charged particle beam apparatus in which a sample stage and a sample holder of the present invention are used.

  This apparatus has an electron gun chamber 3 having an electron gun 2 for taking out an electron beam 1, a focusing lens 4, a deflection coil 5, an objective lens 6, a sample stage 10, a detector 11 a and a detector 11 b, and a sample exchange rod. 7 and an exhaust pump 13 and an exhaust pipe 14 for keeping the inside of the apparatus in a vacuum. The sample 8 (conventional sample stage 18) and the sample holder 9 are installed in the sample chamber using a sample exchange rod 7 (corresponding to an extruded member in claims).

  The electron beam 1 taken out from the electron gun 2 is finely focused by the focusing lens 4 and the objective lens 6, and scans on the sample 8 by the deflection coil 5. The secondary charged particles emitted from the scanned sample 8 are captured by the detector 11a, or the transmitted electrons that have passed through the sample 8 are captured by the detector 11b to perform image observation.

  FIG. 2A is a perspective view showing a detailed configuration of the sample stage having the tilt function of the present invention.

It consists of a sample stage part (corresponding to the movable member in the claims), a sample stage fixing part 17 (corresponding to the rail holding part in the claims), a holder pedestal 15 and a holder fixing part 16 comprising the sample stage 18a and the sample exchange rod receiver 19. It shall be comprised from a base part (equivalent to the attachment part of a claim).

  In order to incline the sample, a guide groove 20 as shown in FIG. 2B is provided in the sample stage fixing part 17, and a guide ball 21 provided in the sample stage 18 and the sample exchange rod receiver 19 (protrusion part of claims) Is a mechanism that slides along the guide groove 20 and tilts the sample stage 18a. Therefore, the sample inclination more than the limit angle of the stage mechanism which cannot be realized by the single stage mechanism of FIB and SEM is achieved.

  Further, in order to make it possible to change the tilt angle inside the apparatus in a vacuum state, a mechanism for changing the sample tilt angle by operating the sample exchange rod 7 is provided in the sample stage. As shown in FIGS. 3 (a) and 3 (b), the sample stage is composed of a sample stage 18a, a sample exchange bar receiver 19, several guide balls 21, and a rotating shaft mechanism 22. The receiver 19 has a structure having a sample exchange rod receiving hole 23a. A rotating shaft mechanism 22 is attached between the sample stage 18a and the sample exchange bar receiver 19, so that the angle of the sample stage 18a can be changed by operating the sample exchange bar 7.

  It is desirable that the sample exchanging rod 7 is not displaced up and down when the sample stage is pushed out. Therefore, as shown in FIG. 2 (b), the lower rail is parallel (straight) to the extrusion trajectory of the extruding rod, and the sample base portion is extruded along this trajectory to fit into the upper rail portion. The sample stage provided with the guide sphere is bent while changing the angle. Of course, such a structure is not necessary as long as the sample replacement rod has a structure that may be displaced up and down when the sample table portion is pushed out. For example, the number of rail grooves may be one (one pair).

  In addition, in the sample holder equipped with this sample tilting mechanism, the sample 8 can be tilted independently. Therefore, when used in combination with the FIB or SEM stage mechanism 24, the biaxial tilting of the sample as shown in FIG. Is possible.

  Further, the transmission electron image observation sample stage 18b has a mesh sample stage fixing screw hole 28 as shown in FIG. 5 for fixing a transmission electron image observation sample fixing stage (mesh sample stage) 27. It is assumed that the sample table holder 25 and the mesh sample table holder screw 26 are provided. In addition, as shown in FIGS. 6 (a) and 6 (b), the pedestal portion is provided with a transmission electron passage hole 29 for enabling transmission electron image observation, enabling high-angle scattered transmission electron image observation. The high-angle scattering transmission electron reflector plate mounting screw hole 30 for attaching the high-angle scattering transmission electron reflector plate 31 is also provided.

  Further, the sample stage 18b is removable, and can be replaced with a sample stage 18c provided with a function capable of fixing a conventional sample stage. FIG. 7 shows a sample stage portion 18c provided with a screw 32 for enabling fixing of the conventional sample stage. Thus, it is possible to apply the conventional sample stage and the sample pretreatment method.

  As shown in FIG. 8, the pedestal portion is composed of a holder pedestal 15 and a holder fixing portion 16a or a holder fixing portion 16b having a sample exchange rod insertion port 23b or a sample exchange rod insertion port 23c, and a sample exchange corresponding to each apparatus. Since only the holder fixing portion 16a or the holder fixing portion 16b provided with the rod receiving hole 23b and the sample exchange rod receiving hole 23c can be exchanged, the sample 8 and the sample table are not limited to FIB and SEM but between any apparatuses having different mounting methods. A mechanism is provided that eliminates the need to replace the 18a and the sample fixing portion 17.

Sectional drawing which shows the structure of a scanning electron microscope. The perspective view of the sample holder and sample stand in this invention. The figure which showed the attachment condition of the sample exchange rod to the axis | shaft rotation mechanism installed between the sample stand and the sample exchange rod holder and the sample stand part. The perspective view which showed that the sample holder and sample stand in this invention enabled biaxial inclination. The schematic diagram which showed the method of fixing a mesh sample stand to the sample stand for transmission electron image observation using a mesh sample stand holder. 1 is a schematic view of a sample holder including a transmission electron image observation sample stage that enables transmission electron image observation, and showing a transmission electron passage hole and a screw hole for fixing a high-angle scattering transmission electron reflector. The perspective view of the sample stand which can attach the conventional sample stand. The perspective view which showed that compatibility was also possible between apparatuses from which a mounting method differs by replacement | exchange of a holder fixing | fixed part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electron beam, 2 ... Electron gun, 3 ... Electron gun chamber, 4 ... Condensing lens, 5 ... Deflection coil, 6 ... Objective lens, 7 ... Sample exchange rod, 8 ... Sample, 9 ... Sample holder, 10 ... Sample stage 11a, 11b ... detector, 12 ... sample chamber, 13 ... exhaust pump, 14 ... exhaust pipe, 15 ... holder base, 16 ... holder fixing part, 17 ... sample base fixing part, 18 ... conventional sample base, 18a ... Sample stage, 18b ... Sample stage for transmission electron image observation, 18c ... Conventional sample stage observation sample stage, 19 ... Sample exchange rod holder, 20 ... Guide groove, 21 ... Guide ball, 22 ... Rotating shaft mechanism, 23 ... Sample exchange Rod receiving hole, 24 ... stage mechanism of charged electron particle beam device, 25 ... mesh sample table holder, 26 ... mesh sample table holder screw, 27 ... sample fixing table (mesh sample table) for transmission electron image observation, 28 ... mesh sample Screw holes for fixing the base, 9 ... transmission electron passing hole, 30 ... high angle scatter transmission electron reflection plate fixing screw holes, 31 ... high angle scatter transmission electron reflection plate, 32 ... conventional sample stage fixing screw.

Claims (4)

A movable member for placing a sample;
A rail portion for moving the movable member along a predetermined route;
A rail holding portion for holding the rail portion;
An attachment part for attaching the rail holding part to the sample stage;
A receiving hole that is provided in the movable member and attaches an extrusion member that pushes the movable member from the outside in order to move the movable member along the rail;
Equipped with a,
The rail portion is a groove provided in the rail holding portion, and a protrusion that fits into the groove is provided in the movable member,
The movable member is composed of two or more constituent members via a bendable connecting portion, and each of the constituent members includes the protrusion.
A charged particle beam apparatus sample stage , wherein the rail holder includes at least two different rail portions corresponding to the constituent members . The sample stage for a charged particle beam device according to claim 1 ,
The rail holder is a pair of opposed parallel flat plates, the charged particle beam apparatus sample stage. The sample stage for a charged particle beam device according to claim 1,
The movable member includes a holding member for the transmission electron microscope sample fixing base so that the transmission electron microscope sample fixing base can be held;
The charged particle beam apparatus sample stage, wherein the attachment portion includes a hole through which an electron beam transmitted through the sample can pass . In the sample stage for a charged particle beam device according to claim 3 ,
A sample stage for a charged particle beam apparatus comprising a high-angle scattering transmission electron reflecting plate in the mounting portion .

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