JP4699168B2 - Electron microscope sample preparation method - Google Patents

Description

  In the present invention, when producing a thin sample for an electron microscope, sample damage such as amorphization of crystals generated on a processing surface by irradiation of a focused ion beam, generation of a mixing layer, processing unevenness on a uniform structure, etc. The present invention relates to a technique that is effective when applied to a sample preparation method for an electron microscope, a focused ion beam apparatus, and a sample support that effectively remove a layer.

  For example, the processing dimensions of silicon semiconductors are miniaturized and highly integrated, and in the development of new processes and mass production processes, deterioration of device characteristics and reduction of reliability are more important than ever. In recent years, two-dimensional analysis using a transmission electron microscope (TEM) and electron energy loss spectroscopy (EELS) has been conducted to fundamentally identify and resolve the causes of the above-mentioned defects. Element distribution analysis / spectral analysis has become an indispensable analytical tool for failure analysis of semiconductor devices in the nanometer range, and it is very effective in failure analysis involving chemical reactions in process development and mass production.

  In addition, in order to thin a defective portion of a silicon semiconductor, which has been clarified by electrical measurement, to such an extent that TEM observation or EELS analysis can be performed, the use of a focused ion beam device (FIB) has rapidly become widespread. Yes. In the focused ion beam apparatus, gallium ions accelerated to several tens of kV are focused on the surface of the sample and sputtered while being scanned to make the sample thin and to have a transmission film thickness capable of TEM observation and EELS analysis.

  FIG. 2 shows a conventional procedure for producing a TEM sample after selecting a specific location from a silicon substrate on which a device pattern is formed using a focused ion beam apparatus. FIG. 2 (a) shows that the selected portion 8 and its surroundings are processed by the focused ion beam 11 so as to include the selected portion 8 from the device pattern 5 formed on the silicon substrate 4 for TEM observation and EELS analysis. It shows where it is.

  FIG. 2B is a diagram in which FIG. 2A is observed from the ion beam irradiation direction. After leaving a part and processing the periphery with a focused ion beam, the probe 7 provided in the focused ion beam apparatus is brought into contact with the upper surface of the sample. While observing the selected portion 8, the probe 7 is fixed to the fixing portion 12 in the selected portion 8 with tungsten gas. After fixing the probe 7, the bottom portion and a part of the side surface of the selected portion 8 are cut, and the silicon substrate 4 and the selected portion 8 are separated (FIG. 2C). The selected portion 8 separated from the silicon substrate 4 becomes the sample piece 2.

  FIG. 2D is a perspective view of the sample piece 2 separated from the silicon substrate. The sample piece 2 is arranged in the order of the tungsten protective layer 3, the device pattern 5, and the silicon substrate 4 deposited so that the upper portion of the selected portion 8 is not damaged by the focused ion beam from the probe 7 side. Usually, when the extracted sample piece 2 is observed with a transmission electron microscope, the sample piece 2 is not fixed to the transmission electron microscope holder as it is, but is fixed to the sample support table for the transmission electron microscope, and then the sample support table. Is placed on a holder for a transmission electron microscope. Further, the same holder can be shared as the holder for the focused ion beam apparatus and the transmission electron microscope. The separated sample piece 2 is fixed to the sample fixing position 13 by the tungsten gas on the sample support 6 and separated from the probe 7 (FIG. 2 (e)). When the sample piece 2 is viewed from the cross-sectional direction, it is as shown in FIG. 2 (f), and the sample support base 6 side is the silicon substrate 4. After being separated from the probe 7, it is sliced with gallium ions so as to have an electron beam transmission film thickness suitable for TEM observation and EELS measurement.

  For example, when thinning is performed using a focused ion beam device to observe a cross section of a laminated film in which a silicon oxide film is deposited on a silicon substrate, the accelerating voltage is thinned with 30 kV gallium ions. As shown, the sample damage layer 22 having a thickness of about 30 nm is formed by irradiating both sides of the processed surface of the observation layer 23 with the focused ion beam 11 in the direction of transmission of the electron beam 21 and making it thin. The sample damage layer 22 includes the formation of a mixing layer in which both layers are disturbed at the interface between the silicon substrate and the silicon oxide film when gallium ions are implanted.

As described above, when observing the crystal layer of a silicon substrate, if the total sample film thickness is reduced by using a focused ion beam, the ratio of the sample damage layer is increased, which greatly affects the image observation. Become. Therefore, when a silicon substrate is observed with a transmission electron microscope, it becomes difficult to obtain a clear lattice image. In addition, it is difficult to clearly determine the boundary in the vicinity of the interface between the silicon substrate and the silicon oxide film. With this present sample damage layer, not transmission electron microscopy alone, can not be carried out in detail the analysis such as an electron beam energy loss spectroscopy. The generation of the sample damage layer is a big barrier especially in the analysis of the laminated interface.

  In addition, as described above, when a selected region is extracted from a silicon substrate on which a device pattern is formed, fixed to a sample support base, and thinned by FIB processing, gallium ion irradiation is from the device pattern side. Therefore, due to the difference in cutting speed between the silicon substrate and the device pattern, processing unevenness (curing) depending on the device pattern is formed on the silicon substrate.

  When processing unevenness is generated on the silicon substrate, when measuring the dopant distribution and concentration implanted in the silicon substrate by electron beam holography, the film thickness in the transmission direction of the electron beam is non-uniform, so measure accurately. It becomes difficult. The same can be said when the strain in the silicon substrate is measured by using convergent electron diffraction.

  In order to solve the above problem, as disclosed in, for example, Patent Document 1, when a thin sample for an electron microscope is manufactured, a sample damage layer generated on the processing surface by sputtering with a focused ion beam is reduced to 1 keV or less. Attempts have been made to remove the sample damage layer by irradiating the thin sample with argon ions accelerated by energy.

In this method, the sample damage layer generated by the focused ion beam is removed by using low-acceleration argon ions, so that the sample damage layer is generated by the focused ion beam without regenerating the sample damage layer by argon ion milling. It is possible to remove the sample damage layer.
JP 2002-277364 A

  As described above, the sample damage layer formed on the processed surface is removed by irradiating with a low acceleration argon ion beam after cutting with the focused ion beam. However, when a sample piece extracted from a silicon substrate on which a device pattern is formed using a probe installed in a focused ion beam apparatus is attached to a sample support, the device pattern side becomes the ion beam irradiation side. . For this reason, even if irradiation with an argon ion beam is performed after thinning with a focused ion beam, the processing unevenness (curing) generated on the silicon substrate cannot be removed.

  Further, when the argon ion beam is irradiated from the sample support base side, since the sample piece is irradiated from the silicon substrate side, the sample damage layer can be removed and the processing irregularity of the silicon substrate can be removed. However, since the argon ion beam is irradiated over a wide range, the foreign matter scraped from the sample support table is reattached to the processing surface, which becomes an obstacle to clear image observation and analysis.

  From the above, the technique of Patent Document 1 is a technique that combines a focused ion beam device and a low-acceleration ion milling device to remove a sample damage layer generated when a sample is thinned by the focused ion beam device. However, it has not been studied from the viewpoint of removing the sample damage layer taking into account the removal of the processing unevenness generated in the above, and is insufficient. In addition, in the case of removing unevenness of processing, re-adhesion of foreign matters from the sample support table or the like is not sufficiently studied.

  Therefore, the present invention solves the problems of the conventional electron microscope sample preparation method and apparatus described above, and performs high-accuracy transmission electron microscope observation and analysis such as electron beam energy loss spectroscopy. Therefore, there is provided a method and apparatus for producing a sample for an electron microscope at a specific location from which various sample damage layers by a focused ion beam are removed.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  In the present invention, when producing an electron microscope sample using an ion beam, the irradiation direction of the ion beam is performed from the uniform structure side.

  That is, in the method of forming a non-uniform pattern on a uniform structure and producing a portion including both of them on a cross-sectional electron microscope sample, the ion beam is incident from the direction of the uniform structure and thinned. To an electron microscope sample preparation method.

  An electron microscope characterized in that a device pattern is formed on a silicon substrate and a portion including both is formed into a sample for a cross-sectional electron microscope, wherein the electron beam is thinned by irradiation with an ion beam from the silicon substrate side. The present invention relates to a sample preparation method.

  A sample for an electron microscope is produced using a focused ion beam and a low acceleration argon ion beam as the ion beam.

  The present invention also provides a focused ion beam apparatus for producing a sample for an electron microscope, a rotation mechanism for rotating a probe for extracting a part of the sample, and a tilt mechanism for tilting the probe. The present invention relates to a focused ion beam device comprising a discriminating device for discriminating a uniform structure side from a secondary particle image.

  When the sample is a silicon substrate on which a device pattern is formed, the sample piece is fixed to the sample support with the silicon substrate side facing the ion beam irradiation side.

  Further, the focused ion beam apparatus for producing a sample for an electron microscope is characterized by comprising a sample rotating means for rotating the upper and lower surfaces of the sample stage and a storage means for storing an extraction position from the sample. The present invention relates to a focused ion beam apparatus.

  When producing a sample for a cross-sectional electron microscope including a non-uniform pattern formed on a uniform structure, the focused ion beam apparatus is fixed to the sample support with the uniform structure side facing the ion beam irradiation side. Therefore, it is possible to irradiate the sample piece extracted from the sample with the focused ion beam or the argon ion beam from the uniform structure side.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  According to the present invention, a sample for an electron microscope having no sample damage layer by a focused ion beam can be produced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

  FIG. 1 includes a device pattern formed on a silicon substrate as an example of a portion including a non-uniform pattern formed on a uniform structure in a sample preparation method for an electron microscope according to an embodiment of the present invention. It is explanatory drawing of an example of the process of producing the cross-sectional sample for the transmission electron microscope of a location, and is the figure immediately after the sample piece 2 was attached to the sample support stand 6. FIG. A section including both the device pattern 5 and the silicon substrate 4 is extracted from the cross-sectional sample for the electron microscope. What is fixed to the sample support 6 is the device pattern 5 side. When preparing a sample for an electron microscope, the ion beam 1 is irradiated from the opposite direction to the sample support base 6 side, that is, from the silicon substrate 4 side. A tungsten protective layer 3 may be deposited on the silicon substrate 4 for surface protection.

(Embodiment 1)
FIG. 4 is a diagram showing a schematic configuration of an example of the focused ion beam apparatus according to Embodiment 1 of the present invention, and shows an example of the focused ion beam apparatus 30. The focused ion beam 11 generated from the ion source 31 is focused by the focusing lens 33 and irradiated onto the large sample 40 fixed to the sample stage 41. The irradiation position of the focused ion beam 11 is designated by the deflection coil 32. The sample stage 41 can be moved by the sample moving mechanism 38 of the sample stage 41. When a part of the large sample 40 is produced as an electron microscope sample, the sample is extracted by the probe 7 having the probe transfer device 39. The probe 7 can be moved in the X, Y, and Z directions by a probe transfer device 39. Further, when fixing the extracted sample to the probe 7, tungsten gas 34 emitted from a tungsten gun 35 is used while irradiating the focused ion beam 11. In order to confirm the extraction position and the probe position, a secondary particle detector 36 that detects secondary particles generated when the focused ion beam 11 is irradiated onto the large sample 40 is used, and a secondary particle image is displayed on the display device 37. Is displayed.

  First, the shape of the upper surface of the sample extracted by the probe 7 is stored in the determination device 44. At this time, since the shape of the upper surface is a rectangle, the length of the long side is measured. Thereafter, the probe 7 is rotated around the probe 7 by the rotation mechanism 42 while the extracted sample is fixed. While the probe 7 is rotating, a secondary particle image is acquired by the secondary particle detector 36. If the long side coincides with the length of the long side measured before the rotation and the long side has a uniform contrast, the discriminator 44 If it is determined, the rotation of the probe 7 is stopped.

  Next, the tilt mechanism 43 is tilted in the vertical direction with the probe 7 as the central axis. Also at this time, a secondary particle image is always obtained, and the determination device 44 determines that the area of the secondary particle image of the sample is minimized. When the area is minimized, the inclination of the probe 7 is stopped.

  In the case of a focused ion beam apparatus equipped with an electron source, the uniform structure side may be determined from the secondary electron image, and the rotation angle / tilt angle of the probe 7 may be determined based on the determination.

  FIG. 5 is a diagram that further embodies the explanation in FIG. 4, and shows an example of a process of rotating and tilting a sample piece extracted from a large sample of a silicon substrate on which a device pattern is formed and fixing the sample piece to a sample support table. It is the figure demonstrated from the irradiation direction of the focused ion beam. A part of the periphery of the selected portion 8 to be extracted from the large sample 40 is left, and after processing with the focused ion beam, the probe 7 is brought into contact with the upper surface of the selected portion 8 to be extracted (FIG. 5A). After the probe 7 is fixed to the fixing portion 12 with tungsten gas (FIG. 5B), the remaining sample periphery is processed (FIG. 5C), and the sample piece 2 is extracted (FIG. 5D). ). When the extracted sample piece 2 is merely rotated by the rotation mechanism 42 in FIG. 4 with the axis of the probe 7 as the rotation axis (FIG. 5E), the sample piece upper surface 55 and the sample piece cross section 56 are observed. . In this case, since the upper surface of the sample piece 2 and the upper surface of the sample support base 6 are not parallel, the probe 7 is inclined by the inclination mechanism 43 of the probe 7 in FIG. The upper surface of the sample support 6 is made parallel (FIG. 5 (f)). Thereafter, the probe moves to the sample support 6 (FIG. 5G), and is fixed to the sample fixing position 13 using tungsten gas on the sample support 6 (FIG. 5H). Is separated from the sample piece 2 (FIG. 5 (i)). Thereafter, thinning is performed for an electron microscope using a focused ion beam (FIG. 5 (j)). After thinning the focused ion beam, the sample damage layer is removed with a low acceleration argon ion beam.

  FIG. 6 is a diagram illustrating an example of the process of FIG. 5 from a direction perpendicular to the irradiation direction of the focused ion beam. That is, it is a view observed from the vertical direction of FIG. FIG. 6A is a sample piece 2 in FIG. 5 extracted from a large sample, and is a view of FIG. 5D observed from the vertical direction. The sample piece 2 in which the device pattern 5 is formed on the silicon substrate 4 is the device pattern 5 on the probe 7 side fixed to the fixing portion 12. After extracting the sample piece 2, the probe 7 is rotated about the axis of the probe 7 (FIG. 6B). In this case, not only the sample piece cross section 56 but also the sample piece upper surface 55 is observed. Next, after the sample piece 2 is tilted (FIG. 6C), it is placed on the sample support 6 (FIG. 6D) and fixed to the sample fixing position 13 (FIG. 6E). Since the sample piece 2 is rotated with the axis of the probe 7 as the rotation axis and then tilted, it is fixed to the sample support base 6 on the device pattern 5 side. After fixing the sample piece 2, the probe 7 is separated from the sample piece 2 (FIG. 6F). 4, 5 and 6, irradiation with an ion beam is possible from the silicon substrate side.

(Embodiment 2)
FIG. 7 is a diagram showing a schematic configuration of an example of a focused ion beam apparatus according to Embodiment 2 of the present invention, and a sample for a transmission electron microscope is produced from a large sample in which a device pattern is formed on a silicon substrate. 1 shows an example in a focused ion beam device. For the sake of simplicity, the same functional parts as those in FIG. 4 are denoted by the same reference numerals as those in FIG.

  A large sample 40 having a device pattern formed on a silicon substrate is placed on a sample table 41. A secondary particle image is acquired by the secondary particle detector 36, displayed on the display device 37, and stored in the storage unit 45. After specifying the sample piece extraction location on the display device 37 and storing it in the storage means 45, the upper and lower surfaces of the large sample 40 are rotated by the sample rotating means 46. After rotating the large sample 40, the extraction position after rotation is calculated from the designated position of the secondary particle image before rotation, the extraction position is transferred from the storage means 45 to the deflection coil 32, and the extraction position is cut. When transferring the extraction position from the storage means 45, the sample moving mechanism 38 may be used instead of the deflection coil 32. Since the sample for thinning is extracted after rotating the upper and lower surfaces of the large sample 40, extraction from the silicon substrate side is possible, and after installation on the sample support base, irradiation with an ion beam is possible from the silicon substrate side. Become.

  8A to 8C are explanatory diagrams of an example of a sample stage on which a large sample is installed. The central portion of the sample stage 41 is a cavity 52 that can transmit the focused ion beam 11. When the large sample 40 is installed on the sample table 41, the sample table 41 is rotated, and therefore, it may be fixed so as not to fall with silver paste or carbon tape. The explanatory diagram of FIG. 8 is an explanatory diagram in the case of a cantilever, but it may be rotated with the sample stage 41 being supported at both ends. In the present invention, since the sample piece is extracted from the silicon substrate side, the silicon substrate side may be polished in advance, or the silicon substrate may be cut with a focused ion beam immediately before extraction.

(Embodiment 3)
FIG. 9 is an explanatory diagram showing an example of a sample support table for fixing a sample piece extracted from a sample when the sample is processed into a transmission electron microscope sample according to Embodiment 3 of the present invention. A projection 51 for fixing the sample piece 2 is provided at the center of the sample support base 6, and the side surface of the sample piece 2 is fixed to the sample support base 6.

  FIG. 10 is an explanatory diagram illustrating an example of a process for producing a sample for an electron microscope using the sample support base according to the present embodiment. When the extracted sample piece 2 is fixed to the sample support 6 using a conventional focused ion beam apparatus, irradiation with the ion beam 1 is on the device pattern 5 side as shown in FIG. However, after fixing the sample piece 2 to the sample support base 6, the sample support base 6 is rotated up and down and reattached to the holder for the focused ion beam device, so that irradiation with the ion beam 1 is performed as shown in FIG. This is possible from the silicon substrate 4 side.

  FIG. 11 shows an explanatory diagram of an example of another sample support base according to the present embodiment. As shown in FIG. 11, the protrusion for fixing the sample piece 2 so as not to hinder the irradiation of the ion beam to the sample piece 2 fixed to the protrusion 51 provided at the center of the sample support base 6. You may use the sample support stand 6 which 51 bent.

  FIG. 12 shows an explanatory diagram of an example of another sample support base according to the present embodiment. When a semicircular sample support base is used, if inconvenience occurs in operations such as pinching with tweezers, a circular sample support base 6 may be used as shown in FIG. It is preferable that the protrusion 51 for installing the sample piece 2 bends the protrusion 51 for fixing the sample piece 2 so as not to be an obstacle when the ion beam is irradiated.

  FIG. 13 shows an explanatory diagram of an example when a sample piece is extracted from a sample using a probe and fixed to a sample support. When the sample piece 2 is extracted using the probe 7, as shown in FIG. 13A, the probe 7 is usually fixed to the fixing portion 12 on the upper surface of the sample piece 2. As shown, the probe 7 may be fixed to the fixing portion 12 on the side surface of the sample piece 2, and the sample piece 2 may be extracted and then fixed to the sample support 6.

  As described above, even when the sample support base is devised, ion beam irradiation can be performed from the silicon substrate side.

  Next, a specific example of the above embodiment will be shown. First, the observation result by low magnification is shown. A sample piece in which a device pattern was formed on a silicon substrate was observed with a transmission electron microscope after the cross-sectional thin film was processed. This time, the sample support 6 of FIG. 11 was used to process the thin film of the sample piece.

  In order to make the sample piece fixed on the sample support base into a thin piece, it was first made into a thin piece using a focused ion beam apparatus. The acceleration voltage of the focused ion beam was always 30 kV, the current amount was lowered in the order of rough machining, intermediate machining, and finishing machining, and the current amount during finishing machining was 30 pA.

  After thinning with a focused ion beam, the sample damage layer was removed with a low acceleration argon ion beam. As the irradiation conditions of the low acceleration argon ion beam, milling was first performed at 2 kV for 1 minute and then milled at 100 V for 10 minutes. Both surfaces of the process were milled with a low acceleration argon ion beam. The final sample film thickness in the electron beam transmission direction was about 100 nm.

  FIG. 14A shows the result of observation of a cross-sectional transmission electron microscope sample manufactured under these conditions with a normal transmission electron microscope. Further, FIG. 14B shows a cross-sectional sample produced using a conventional technique taken with a transmission electron microscope. Observation with a transmission electron microscope was performed at an acceleration voltage of 300 kV and an observation magnification of 10,000 times. In FIG. 14B, a contrast difference is generated in the transmission electron microscope image on the silicon substrate 4. The contrast difference seen on the silicon substrate 4 means that the processing unevenness occurs in the silicon substrate 4 due to the difference in the sputtering rate due to the ion beam between the device pattern 5 and the silicon substrate 4. However, when a sample is prepared using the sample support base of the present invention, as shown in FIG. 14A, the silicon substrate 4 in the transmission electron microscope image has a uniform contrast, and processing unevenness can be removed. You can see that

  Next, the observation result by high magnification is shown. A sample in which a silicon oxide film was deposited on a silicon substrate by a CVD method was observed.

The cross-section sample preparation method is as described above. Transmission direction of the sample film thickness of the final electron beam was about 50nm.

  FIG. 15A shows the result of observation of a cross-sectional transmission electron microscope sample manufactured under these conditions with a normal transmission electron microscope. Further, FIG. 15B shows a cross-sectional sample produced by a conventional technique taken with a transmission electron microscope. Observation with a transmission electron microscope was performed at an acceleration voltage of 300 kV and an observation magnification of 300,000 times. From both transmission electron microscope images, it can be seen that the image quality (lattice image is clear) of the lattice image of the silicon substrate 4 is remarkably improved. This is because the amorphous sample damage layer on the silicon substrate 4 generated by the focused ion beam was removed by argon ion milling. The interface between the silicon substrate 4 and the silicon oxide film 60 is also sharp. This means that the mixing layer generated by the focused ion beam between the silicon substrate 4 and the silicon oxide film 60 has been removed by argon ion milling.

  As described above, according to the electron microscope sample preparation method and the focused ion beam apparatus of each of the embodiments described above, when a sample for an electron microscope is prepared using a focused ion beam, the sample damage due to the focused ion beam is reduced. A sample for an electron microscope without a layer can be produced.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  In the present invention, when producing a thin sample for an electron microscope, sample damage such as amorphization of crystals generated on a processing surface by irradiation of a focused ion beam, generation of a mixing layer, processing unevenness on a uniform structure, etc. It is effective when applied to a sample preparation method for an electron microscope, a focused ion beam apparatus, and a sample support that effectively remove the layer.

It is explanatory drawing which shows an example of the process of producing the cross-sectional sample for transmission electron microscopes by embodiment of this invention. (A)-(f) is explanatory drawing which shows the process of producing the sample for transmission electron microscopes by a prior art. It is explanatory drawing which shows the sample damage layer by a focused ion beam in a prior art. It is a schematic block diagram which shows an example of the focused ion beam apparatus by Embodiment 1 of this invention. (A)-(j) is explanatory drawing which shows an example of the preparation process of the sample for transmission electron microscopes by Embodiment 1 of this invention. (A)-(f) is explanatory drawing which shows an example of the preparation process of the sample for transmission electron microscopes by Embodiment 1 of this invention. It is a schematic block diagram which shows an example of the focused ion beam apparatus by Embodiment 2 of this invention. (A)-(c) is explanatory drawing which shows an example of the sample stand which installs a sample in Embodiment 2 of this invention. In Embodiment 3 of this invention, it is explanatory drawing which shows an example of the sample support stand which fixes a sample piece. (A), (b) is explanatory drawing which shows an example of the process of producing the cross-sectional sample for transmission electron microscopes in Embodiment 3 of this invention. In Embodiment 3 of this invention, it is explanatory drawing which shows an example of another sample support stand. In Embodiment 3 of this invention, it is explanatory drawing which shows an example of another sample support stand. (A), (b) is explanatory drawing which shows an example of fixation between a probe and a sample piece in Embodiment 3 of this invention. The low magnification transmission electron microscope image (a) obtained using the sample support stand by embodiment of this invention and the low magnification transmission electron microscope image (b) obtained using the prior art are shown. It is explanatory drawing. Explanatory drawing which shows the high magnification transmission electron microscope image (a) obtained using the sample support stand by embodiment of this invention, and the high magnification transmission electron microscope image (b) obtained using the prior art It is.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Ion beam, 2 ... Sample piece, 3 ... Tungsten protective layer, 4 ... Silicon substrate, 5 ... Device pattern, 6 ... Sample support stand, 7 ... Probe, 8 ... Selected location, 11 ... Focused ion beam, 12 ... Fixing part, 13 ... sample fixing position, 21 ... electron beam, 22 ... sample damage layer, 23 ... observation layer, 30 ... focused ion beam device, 31 ... ion source, 32 ... deflection coil, 33 ... focusing lens, 34 ... tungsten Gas 35, tungsten gun 36 ... secondary particle detector 37 ... display device 38 ... sample moving mechanism 39 ... probe transfer device 40 ... large sample 41 ... sample stage 42 ... rotating mechanism 43 ... Inclining mechanism, 44 ... discriminating device, 45 ... storage means, 46 ... sample rotating means, 51 ... projection, 52 ... cavity, 55 ... upper surface of sample piece, 56 ... cross section of sample piece, 60 ... silicon oxide film.

Claims (3)

In a method for producing a sample for an electron microscope,
Preparing a sample having a silicon substrate and a device pattern formed on the silicon substrate;
Fixing the side surface of the sample to a sample support;
Irradiating an ion beam from the silicon substrate side toward the sample, processing the silicon substrate, and subsequently processing the device pattern with the ion beam irradiated from the silicon substrate side toward the sample. ,
A method for preparing a sample for an electron microscope. The method for producing a sample for an electron microscope according to claim 1, wherein the sample is fixed to the sample support base only on a side surface of the sample. The method for producing a sample for an electron microscope according to claim 1, wherein the sample support has a protrusion, and the sample is fixed to the protrusion.