JP2009259556A - Electron microscope observation sample supporting member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electron microscope observation sample supporting member which, when a finer sample piece is extracted from a sample to process it as an electron microscope observation sample in FIB processing, an FIB processing ion beam is not emitted on the electron microscope observation sample supporting member for fixing the fine sample piece to prevent the occurrence of redeposition on the sample. <P>SOLUTION: Because a flake fixing portion 5 is sufficiently thinner than the fine sample piece 2, processing without cutting the flake fixing portion 5 is possible even if an ion beam 6 is tilted to fall to an electron microscope observation sample portion at the center of the fine sample piece 2. This prevents the production of fine powder from the flake fixing portion 5, so that no redeposition occurs on the observation sample. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electron microscope observation sample support member used for fixing a sample piece extracted by focused ion beam (hereinafter referred to as FIB) processing.

  In FIG. 5, the state before FIB processing of the conventional sample piece for electron microscope observation is shown. The micro sample piece 2 is fixed to the electron microscope observation sample support member 1 by the deposition film 3, and the thickness width of the electron microscope observation sample support member 1 and the sample thickness width of the micro sample piece 2 are the same thickness. It is wide.

  FIG. 6 is an explanatory diagram of conventional FIB processing. 6A is a perspective view, and FIG. 6B is a cross-sectional view of the center portion of the sample piece. As shown in FIG. 6A, in order to obtain a desired thickness width of 500 to 1000 mm, the Ga ion beam 6 is focused from the FIB above the micro sample piece 2 and is placed at a desired position on the micro sample piece 2. The ion sample 6 is irradiated and the processing of the micro sample piece 2 proceeds. During the processing, the sample support member 1 for the electron microscope to which the minute sample piece 2 is fixed is also irradiated with the ion beam 6, and the sample support member 1 for the electron microscope observation is also shaved. As a result, the fine powder 7 from the electron microscope observation sample support member 1 shaved by the ion beam 6 is reattached to the fine sample piece 2.

  6B, since the sample processing by FIB is performed by sequentially scanning the Ga ion beam 6 from the upper side to the lower side of the micro sample piece 2, the sample is processed from the upper part of the micro sample piece 2, and the micro sample piece 2 When the processing advances to the vicinity of the interface between the electron microscope observation sample support member 1, the fine powder 7 is generated, so that the fine powder 7 adheres to the upper portion of the already processed fine sample piece 2.

  FIG. 7 shows a transmission electron micrograph of a sample to which the fine powder 7 is actually attached. The black spots recognized in the white dotted line in FIG. 7 are the remarkable deposits of the fine powder 7. When this fine powder 7 is analyzed with an energy dispersive X-ray analyzer (EDS) attached to a transmission electron microscope, copper element (Cu) that should not be contained in this sample piece is detected. This uses a sample support member made of copper, and is a deposit derived therefrom. Thus, it is needless to say that the fact that elements that are not originally included in the sample adhere to the observation surface and are detected is a great obstacle in structural analysis.

  When fixing a conventional micro sample piece to a sample support member for electron microscope observation, the micro sample piece is fixed to the end of a silicon piece formed by cleaving from a silicon wafer or using a dicing saw as a sample support member for electron microscope observation. Was.

  In Patent Document 1, only a sample piece including a desired specific region is extracted from a bulk sample and formed on a silicon (Si) piece having a knife edge shape of 1 mm × 2.5 mm × 0.1 mm by FIB irradiation. An example of a sample preparation method that is fixed using a deposition film and mounted on a sample stage of a sample preparation apparatus is shown.

  In Patent Document 2, when a finer sample piece is extracted from a sample by FIB processing and processed as an electron microscope observation sample, the extracted fine sample piece can be easily fixed and handled safely. An example of an electron microscope observation sample support member is shown.

Japanese Patent Laid-Open No. 11-108813 JP 2001-124676 A

  However, in the above prior art, when processing after fixing the sample piece to the sample piece fixing portion, the FIB ion beam is applied not only to the fine sample piece but also to the electron microscope observation sample support member, and a part of it is irradiated. There is a problem that the fine powder generated by the processing of the electron microscope observation sample support material is reattached to the sample.

  This reattachment to the sample is a serious hindrance factor in the subsequent structural analysis by electron microscope observation, and provides information different from the original composition / structural analysis. Become.

  The object of the present invention is to compensate for these drawbacks, and when a finer sample piece is extracted from the sample by FIB processing and processed into an electron microscope observation sample, the FIB ion beam is used for electron microscope observation for fixing the sample piece. An object of the present invention is to provide an electron microscope observation sample support member that does not irradiate the sample support member and does not reattach to the sample.

  Therefore, the present invention is to fix a sample piece with a flat mounting surface for fixing the extracted micro sample piece when processing the micro sample piece extracted from the sample with a focused ion beam into a sample piece for electron microscope observation. An electron microscope observation sample supporting member having a central portion of a sample piece for electron microscope observation thinned with a focused ion beam for observation with an electron microscope. The sample supporting member for electron microscope observation is characterized in that the thickness of the thin piece fixing portion is thinner than the thickness of the central portion of the sample piece for electron microscope observation.

  In addition, when processing a micro sample piece extracted from a sample with a focused ion beam into a sample piece for electron microscope observation, the sample surface has a flat sample piece fixing portion for fixing the extracted micro sample piece. A sample support member for electron microscope observation, in which a central part of a sample piece for electron microscope observation thinned with a focused ion beam is placed for observation with an electron microscope. An electron microscope observation sample support member characterized by being a cavity.

  Furthermore, the sample support member for observing an electron microscope is provided with a plurality of sample piece fixing portions.

  Further, the electron microscope observation sample support member is characterized in that the material of the electron microscope observation sample support member is made of any one of Cu, Pt, Mo, and stainless steel.

  By using the sample support member for an electron microscope according to the present invention, it has a structure in which re-deposition of the fine powder from the sample support member does not occur at the time of processing the sample piece. From the analysis by the subsequent transmission electron microscope observation and the structural analysis Information on the original sample state can be provided.

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

(Embodiment 1)
FIG. 1 shows an example of a schematic configuration diagram of an electron microscope observation sample support member according to an embodiment of the present invention. FIG. 1A is a perspective view, and FIG. 1B is a cross-sectional view of the center portion of a sample piece cut along line AA. As an example, the sample support member 1 for electron microscope observation according to Embodiment 1 has a circular shape with a diameter of 3 mm and a thickness of 100 μm, and the inside of the mesh is made of Pt, and the mounting surface of the sample is flat by FIB processing. As shown, the sample piece fixing part 4 and the thin piece fixing part 5 are processed into the semicircular shape shown in FIG. The thin sample part 2 is thinned and roughly processed into an electron microscope observation sample shape, and fixed by the sample film fixing part 4 by the deposition film 3. At that time, the shape of the thin piece fixing portion 5 in the central portion is such that the thickness of the thin piece fixing portion of the final processed sample piece fixing portion is thinner than the thickness of the central portion of the sample piece for electron microscope observation. When the minute sample piece 2 is fixed to the sample piece fixing portion 4, the FIB is scanned while the deposition gas flows out, and the deposition film 3 is formed in the scanned FIB irradiation region to fix the minute sample piece 2 ing.

  FIG. 2 is an explanatory diagram of FIB processing according to the embodiment of the present invention. 2A is a perspective view, and FIG. 2B is a cross-sectional view of the center portion of the sample piece cut along the line BB. As shown in FIG. 1, after fixing the sample, the ion beam 6 of Ga is irradiated from the FIB above the fine sample piece 2 to make it into a thin piece, which is processed into a sample thickness for electron microscope observation. Usually, a FIB Ga ion beam 6 can be irradiated to a desired position of a desired minute sample piece 2 by focusing. At that time, the Ga ion beam 6 is slightly wider above the focusing portion. Therefore, the sample is not parallel to the minute sample piece 2 and the sample is cut. Therefore, normally, as shown in FIG. 2B, the sample is tilted by 1 to 2 ° in accordance with the focusing angle of the ion beam 6 and irradiated to the minute sample piece 2.

  In the present invention, since the thin piece fixing portion 5 is sufficiently thinner than the micro sample piece 2 after the thin piece, even if the ion beam 6 is inclined and irradiated to the central portion of the sample for electron microscope observation of the fine sample piece 2, the thin piece fixing portion 5 is used. It is possible to process without cutting. As a result, generation of fine powder from the thin piece fixing portion 5 does not occur, and therefore, re-adhesion to the observation sample does not occur.

(Embodiment 2)
FIG. 3 shows an example of a schematic configuration diagram of an electron microscope observation sample support member according to an embodiment of the present invention. A flat sample piece fixing portion 4 for fixing the minute sample piece 2 is formed on the sample support member 1 for electron microscope observation according to the second embodiment, and the sample piece fixing on which the minute sample piece 2 is placed. A cavity 8 is provided immediately below the central part of the electron microscope observation sample that has been thinned for electron microscope observation of the part 4. Thus, when the minute sample piece 2 is irradiated with the ion beam and processed, the sample piece fixing portion 4 is not irradiated with the ion beam, so that the fine powder is not generated.

(Embodiment 3)
FIG. 4 shows an example of a schematic configuration diagram of an electron microscope observation sample support member according to an embodiment of the present invention. The sample support member 1 for electron microscope observation of Embodiment 3 has a structure in which a plurality of sample piece fixing portions 4 are provided. As a result, it is possible to fix a plurality of samples to one electron microscope observation sample support member, and it is possible to observe a plurality of samples without replacing the samples during the observation. Shortening and specific efficiency of the observation place can be achieved.

  As described above, a specific example of the electron microscope observation sample support member 1 used in the embodiment is a thin disk shape having a diameter of 3 mm and a thickness of 10 to 100 μm. , Slit, or mesh, and the material is Cu, Pt, Mo, or stainless steel.

The schematic block diagram of the sample support member for electron microscope observation concerning embodiment of this invention. FIG. 1A is a perspective view, and FIG. 1B is a cross-sectional view of a central portion of a sample piece cut along line AA. Explanatory drawing of FIB processing concerning embodiment of this invention. 2A is a perspective view, and FIG. 2B is a cross-sectional view of the center of the sample piece cut along the line BB. The schematic block diagram of the sample support member for electron microscope observation concerning embodiment of this invention. The schematic block diagram of the sample support member for electron microscope observation concerning embodiment of this invention. The figure which shows the state before FIB process of the sample piece for conventional electron microscope observation. Explanatory drawing of the conventional FIB process. FIG. 6A is a perspective view, and FIG. 6B is a cross-sectional view of the center portion of the sample piece. A transmission electron micrograph of a sample to which fine powder is adhered.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sample support member for electron microscope observation 2 Micro sample piece 3 Deposition film | membrane 4 Sample piece fixing | fixed part 5 Thin piece fixing | fixed part 6 Ion beam 7 Micro powder 8 Cavity part

Claims (4)

  An electron having a sample piece fixing portion with a flat mounting surface for fixing the extracted micro sample piece when processing the micro sample piece extracted from the sample with a focused ion beam into a sample piece for electron microscope observation A sample support member for microscope observation, wherein a thin piece of the sample piece fixing portion on which a central portion of the sample piece for electron microscope observation thinned with the focused ion beam is placed for observation with an electron microscope An electron microscope observation sample support member, wherein a thickness of the fixing portion is thinner than a thickness of a central portion of the electron microscope observation sample piece.   An electron having a sample piece fixing part with a flat mounting surface for fixing a micro sample piece extracted from a sample with a focused ion beam to process the sample piece for electron microscope observation. A sample support member for microscope observation, wherein a central portion of the sample piece for electron microscope observation thinned with the focused ion beam is placed for observation with an electron microscope. A sample support member for observing an electron microscope, characterized in that the portion is hollow.   The sample support member for electron microscope observation according to claim 1 or 2, wherein a plurality of the sample piece fixing portions are provided.   4. The electron microscope observation sample support member according to claim 1, 2 or 3, wherein a material of the electron microscope observation sample support member is made of any one of Cu, Pt, Mo, and stainless steel.

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