JP5420452B2 - Sample cross-section manufacturing apparatus and manufacturing method using ion beam - Google Patents

Description

    The present invention relates to a sample cross section preparation apparatus capable of producing a smooth and clean sample cross section using an ion beam and a shielding material.

  When analyzing a defect inside a semiconductor or the like, it is a common practice to process a cross-section of a defective portion using a focused ion beam (FIB) and observe it with a scanning electron microscope (SEM) or a transmission electron microscope (TEM). However, the cross-section processing by FIB has a drawback that it involves destruction of the sample.

  By the way, samples that are subject to cross-sectional observation by SEM or TEM include samples other than semiconductor samples, such as soft samples, heat-sensitive samples, water-absorbing samples, samples that are difficult to embed resin, etc. There are many. As a cross-section preparation method of these samples, a sample preparation method in which a shield is placed on the sample and the sample is irradiated without spreading the ion beam (hereinafter referred to as “CP method”: Cross section Polisher method) (For example, see Japanese Patent No. 3263920 in the patent literature). The CP method is said to be able to obtain a good cross-section with less structural change than the FIB method, particularly in a composite material or a material having a porous structure made of different materials having different hardnesses. Furthermore, as compared with the FIB method, pre-processing is simple and there is no need for skilled work, so that there is an advantage that a cross-section can be easily produced in a short time.

  As an improvement technique of the sample preparation apparatus of Patent Document 1, Japanese Patent No. 4208658 of Patent Document 2 discloses a technique related to an apparatus provided with an optical microscope for adjusting the cross-section preparation position. The conventional cross-section sample preparation technique will be briefly described below with reference to Japanese Patent No. 4208658.

  In order to facilitate understanding of the description, coordinate axes X, Y, and Z that are orthogonal to each other are defined in the drawing, and the coordinate axes are represented on the drawing. In this notation, “○” in “◯” indicates an arrow heading from the back of the page to the front, and “X” in “○” is the front of the page. It means an arrow pointing from the back to the back.

  FIG. 6 is a side view showing a schematic configuration example of the entire conventional sample cross-section preparation apparatus. In FIG. 6, an ion gun (ion beam irradiation means) 2 is attached to the upper part of the vacuum chamber 1. The central axis Oi of the ion beam IB emitted from the ion gun 2 is substantially parallel to the z axis. The sample stage drawing mechanism 3 is attached to the vacuum chamber 1 so as to be openable and closable. FIG. 6A shows a state where the sample stage drawing mechanism 3 is opened (drawn state), and FIG. 6B shows a closed state. The processing chamber 18 is evacuated by the exhaust device 17 in a state where the sample stage drawing mechanism 3 is closed. A sample stage 4 is attached to the sample stage drawing mechanism 3 so as to be inclined around the y-axis. A sample position adjusting mechanism 5 is arranged on the sample stage 4 so that the sample holder 7 mounted on the sample position adjusting mechanism 5 and the sample 6 placed on the sample holder 7 can be moved in the x and y axis directions. It is configured. The shielding material 12 held by the shielding material holding mechanism 13 is attached to the shielding material tilting mechanism 11 so as to be tiltable. The shielding material holding mechanism 13 can be rotated around an axis q parallel to the x axis to retract the shielding material 12 from the sample 6. A shielding material position adjusting mechanism 10 is arranged on the sample stage 4 and configured to be movable in the y-axis direction. The optical microscope position adjusting mechanism 16 that holds the optical microscope 15 is attached to the optical microscope tilting mechanism 14 so as to be tiltable. As shown in FIG. 6B, when the sample stage drawing mechanism 3 is closed, the optical microscope 15 and the optical microscope position adjusting mechanism 16 rotate around an axis r parallel to the x axis to move outside the vacuum chamber 1. It is comprised so that it may be located in.

  Here, in the sample cross-section preparation apparatus having the configuration shown in FIG. 6, a procedure for cross-section preparation positioning performed prior to cross-section preparation will be briefly described. First, in the state of FIG. 6B in which the sample stage drawing mechanism 3 is closed and the processing chamber 18 is evacuated, an ion beam IB is irradiated to an arbitrary position on the sample 6 for a predetermined time to form an ion beam mark. Next, in the state of FIG. 6A in which the sample stage extraction mechanism 3 is opened and the processing chamber 18 is opened to the atmosphere, the optical microscope position adjustment mechanism 16 is operated, and the ion beam trace comes to the center of the visual field of the optical microscope 15. Thus, the position of the optical microscope 15 is adjusted. Thereby, the optical axis OL of the optical microscope 15 can be made to coincide with the ion beam irradiation axis Oi. Subsequently, the operator operates the “shielding material y moving knob” (not shown) provided in the shielding material position adjusting mechanism 10 while observing the shielding material 12 with the optical microscope 15. The edge position is adjusted so as to be positioned on the optical axis OL. Subsequently, the operator operates the “sample x moving knob” and “sample y moving knob” (not shown) provided in the sample position adjusting mechanism 5 while observing the sample 6 with the optical microscope 15. The cross-sectional production position of the sample 6 is adjusted so that it is located directly below the edge of the shielding material 12.

  When the cross-section production position can be determined as described above, the sample stage drawing mechanism 3 is closed again and the processing chamber 18 is evacuated to the state shown in FIG. 6B, and the cross-section production is performed by irradiating the ion beam IB. .

  FIG. 7 is a diagram for explaining a pre-preparation method when a cross-section is formed using an ion beam. FIG. 7A is a diagram (plan view) of a plate-like sample 6 ′ including the foreign material 30 (observation target site) viewed from the plane direction. There are cases where the foreign matter 30 can be observed directly from the outside of the sample 6 ′ with the naked eye, an optical microscope, or the like, or the presence of the foreign matter 30 cannot be confirmed unless it is seen through using X-rays. In any case, the observation target site in the sample 6 ′ is found by some means, and preparation for sample preparation is performed. For example, as shown in FIG. 7A, markers 31a and 31b are drawn so as to sandwich the foreign material 30 using a sign pen or the like, and an approximate target position of the cross-section production position is determined.

  FIG. 7B is a plan view for explaining a method of preparing the sample 6 for cutting the vicinity of the cross-section preparation position C of the sample 6 ′ with a cutting machine and mounting it on the cross-section preparation apparatus. The area 6a is cut by cutting the vicinity of the markers 31a and 31b. The area 6b is a damaged area lost at the time of cutting, and is determined by the thickness of the blade of the cutting machine to be used, the size of the rotational shake of the blade, and the like.

  FIGS. 7C and 7D are diagrams for explaining an operation of mounting the sample 6 including the observation target part on the sample holder 7 of the cross-section preparation apparatus and aligning the edge of the shielding material 12 with the cross-section preparation position C. FIG. FIG. 7C shows a side view and FIG. 7D shows a plan view. While observing the sample 6 and the shielding material 12 with the optical microscope 15, the edge portion of the shielding material 12 is aligned with the cross-section production target position by the procedure described above.

FIG. 4 is a schematic diagram for explaining how a cross section is formed when a cross section of a sample is prepared. The portion of the sample 6 that is not shielded by the shielding material is gradually cut by irradiation with the ion beam IB. FIG. 4A shows a state immediately after cutting has started, FIG. 4B shows a state in which cutting is in progress, and FIG.

Japanese Patent No. 3263920 Japanese Patent No. 4208658

  If cross-section preparation is performed as in the state shown in FIG. 4C, a flat cross-section should appear at the edge position of the shielding material. However, there is a case where the original structure cannot be observed due to a difference in level or contamination on the cross section.

  This problem is that when the portion of the sample that is not shielded by the shielding material (hereinafter abbreviated as “protruding portion”) is cut by ion beam irradiation, the scraped material is applied to the edge of the shielding material or the processed portion of the sample. This is thought to be due to the phenomenon of redeposition.

  FIG. 5 is a schematic diagram for explaining the redeposition phenomenon. In FIG. 5A, the substance scattered from the protruding portion of the sample 6 by the irradiation of the ion beam IB is reattached to the edge portion of the shielding material 12 to form a deposit 12a. Since the deposit 12a acts as a new shielding material, the region 6a becomes a shadow of the deposit 12a with respect to the irradiation of the ion beam IB. Since the deposit 12a grows conversely as the protruding portion of the sample 6 is cut and becomes smaller, the deposit 12a gradually covers the section that should have been obtained. For this reason, a step is produced, or the finish is incomplete and a flat cross section cannot be obtained.

  According to the inventor's experiment, it has been found that the influence of the redeposition phenomenon can be almost ignored if the protrusion amount L in FIG. However, when the foreign object 30 to be observed is small, considering the damaged region 6b in FIG. 7, the protrusion amount L (that is, the distance from the cross-section production target position to the cutting surface by the cutting machine) needs to be at least about 25 μm to 75 μm It is. When the protrusion amount L is about 25 μm to 75 μm, it is difficult to avoid the influence of the redeposition phenomenon.

  FIG. 5B is a schematic diagram for explaining another redeposition phenomenon. When the cutting of the protruding portion proceeds by the ion beam IB, the upper side of the protruding portion is largely cut, but the lower side is still in a state where the remaining portion protrudes. For this reason, the substance scattered from the remaining lower part is reattached as a stain to the cross section after the processing is completed. Therefore, even if the cross section produced by SEM etc. is observed, an original cross-sectional structure cannot be known.

  The present invention has been made to solve the above-described problems. The purpose of the present invention is to produce a cross-sectional sample by irradiating a sample with an ion beam. An object of the present invention is to provide a sample preparation apparatus and a sample preparation method for removing the influence of redeposition of redeposition and producing a flat sample cross section free from steps and dirt.

To solve the above problem,
(1) In the first aspect of the invention, a part of the sample is covered with a shielding material, and the sample is irradiated with an ion beam from the ion beam irradiation means from the shielding material side including the edge of the shielding material. A sample cross-section preparation apparatus for cutting a portion of the sample that is not shielded by the shielding material with the ion beam to produce a cross-section of the sample, the edge of which is a cross-section of the sample The ion beam is not irradiated to the edge of the first shielding material and the cross-sectional production position of the sample between the first shielding material set at the production position and the first shielding material and the ion beam irradiation means. The second shielding material is arranged in such a manner that it has an edge, and the ion beam from the ion beam irradiation means irradiates the second shielding material including the edge and the portion to be cut of the sample. The second shielding material and the front And characterized in that the second shielding member the ion beam and a second shielding member position moving means for moving to the retracted position to be irradiated to cross making the position of the edges and the sample of the first shielding member To do.
(2) The invention described in claim 2 is provided with a second shielding material position control means for controlling the second shielding material position moving means, and the second shielding material position control means is an end of the first shielding material. The ion beam irradiation is performed in such a manner that the information on the reference position where the edge portion is arranged at the cross-section preparation position of the sample is stored and the cross-section preparation position of the sample and the cutting target portion are shielded by the second shielding material Is started, the edge portion of the second shielding material is directed toward the reference position as cutting of the portion of the sample that is not shielded by the second shielding material proceeds based on the stored reference position information. The second shielding material is moved so as to approach, the edge of the second shielding material exceeds the reference position, and the ion beam is not shielded by the edge of the first shielding material and the first shielding material. When the part is irradiated And controlling the second shielding member position moving means to stop the movement of the second shielding member.
(3) In the invention according to claim 3, the sample is covered with a shielding material, and the sample is irradiated with an ion beam from the shielding material side including an edge of the shielding material. A method for preparing a cross section of a sample for cutting a portion to be cut that is not shielded by the shielding material with the ion beam to produce a cross section of the sample . The first step of arranging the edge portion of one shielding material, and the second shielding material arranged between the first shielding material and the ion beam irradiation means before the ion beam irradiation, the sample of the sample A second step of setting a relative position between the second shielding material and the sample so that the cross-section creation position and the cutting target portion are shielded, and shielding the second shielding material of the sample by the ion beam irradiation. Cutting object that is not After the third step of cutting the portion and the third step, the edge of the first shielding material is not shielded by the second shielding material, and the ion beam is placed at the cross-section preparation position of the sample. And a fourth step of performing ion beam irradiation by placing the second shielding material at a position to be irradiated .
(4) In the invention according to claim 4, in the third step, as the cutting of the part to be cut that is not shielded by the second shielding material of the sample progresses, the cutting with respect to the sample proceeds in the direction in which the cutting proceeds. The position of the edge part of the second shielding material is changed .

  According to the present invention, even if the distance from the end of the sample subjected to the cross-section processing by irradiating the ion beam to the cross-section processing position is long, the sample or the shielding material is moved during the processing and is shielded by the sample shielding material. Since the unextruded protrusion is cut with an ion beam, the effect of redeposition, in which the material removed by the ion beam re-adheres to the shielding material or sample, is removed, and a flat sample cross-section without steps and dirt is created. be able to.

It is a side view which shows the principal part of the sample preparation apparatus which concerns on this invention. It is a side view which shows the principal part of the other sample preparation apparatus which concerns on this invention. It is a side view which shows the principal part of the other sample preparation apparatus which concerns on this invention. It is a schematic diagram for demonstrating a mode that a cross section is formed with a sample preparation apparatus. It is a schematic diagram for demonstrating a redeposition phenomenon. It is a side view which shows the schematic structural example of the whole conventional sample cross-section preparation apparatus. It is a schematic diagram for demonstrating the preparation method when performing cross-section preparation using an ion beam. It is a schematic diagram for demonstrating the process which produces a sample cross section using the sample preparation apparatus which concerns on this invention. It is a schematic diagram for demonstrating the process of producing a sample cross section using the other sample preparation apparatus which concerns on this invention. It is a schematic diagram for demonstrating the process of producing a sample cross section using the other sample preparation apparatus which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the technical scope of the present invention is not limited by this illustration. In each figure, those that perform the same or similar operations as those of the sample preparation device of FIG. The definition of the coordinate axes X, Y, and Z axes displayed in each figure is the same as that in FIG.

(Embodiment 1)
FIG. 1 is a side view showing a main part of a sample preparation apparatus 100 according to the present invention. In the sample preparation apparatus 100, reference numeral 22 denotes a driving device for moving the sample position adjusting mechanism 5 by a minute amount in the y-axis direction, and reference numeral 22 a denotes a piezo motor incorporated in the driving device 22. 21 is a control device for controlling the drive device 22, and 20 is a control arithmetic device such as a personal computer.

  A process of preparing a sample cross section using the sample preparation apparatus 100 configured as shown in FIG. 1 will be described with reference to FIG.

  FIG. 8A shows a cross-section of the edge of the shielding material 12 in a state where the processing chamber 18 of the sample preparation apparatus 100 is opened to the atmosphere as shown in FIG. 6A before the sample is irradiated with the ion beam. It is a side view which shows the state when set to the position C (middle of the foreign material 30). While observing the surface of the sample 6 using the optical microscope 15, the “sample y moving knob” provided in the sample position adjusting mechanism 5 is moved to position the cross-section production position C. FIG. 8A shows a state in which the position P1 on the Y axis of the cross-section production position C is determined so that the cross section of the foreign material 30 in the sample 6 is produced. The control arithmetic unit 20 stores the coordinates of P1.

  In this state, since the protruding portion of the sample 6 that is not shielded by the shielding material 12 is too long, the sample holder 7 is driven by the piezo motor 22 to move the sample 6 by the distance d in the negative direction of the Y axis, and the portion that is not shielded by the shielding material 12 Make it smaller. P2 is the initial position of the cross-section production position C at the start of processing. FIG. 8B shows a state in which the protruding portion is set short when the ion beam irradiation is started on the sample 6.

  When the control arithmetic unit 20 stores the coordinates of P1 and P2, the processing chamber 18 of the sample preparation apparatus 100 is evacuated with the state shown in FIG. 6B.

  When the processing chamber 18 reaches a predetermined degree of vacuum, irradiation of the sample 6 with the ion beam IB is started. The control arithmetic unit 20 drives the sample holder 7 by the piezo motor 22 as the cutting of the protruding portion of the sample 6 proceeds, and gradually moves the cross-section preparation position C from P2 to P1. FIG. 8C shows a state in which the foreign object 30 is at the position P3 while moving from the position P2 to the position P1.

  For example, assuming that the protrusion amount is set to 25 μm first, cutting is performed without moving the sample 6 in the state shown in FIG. 8B for about 20 minutes from the start of processing. During the processing time of 20 minutes to 95 minutes, the sample 6 is moved continuously or intermittently in the direction of protruding from the shielding material 12 in the state shown in FIG. 8C at a speed of about 1 μm / minute. During the period from 95 minutes to 120 minutes (end of processing), the movement of the sample 6 is stopped, and cutting with the ion beam IB is performed while the cross-section production position C is fixed to P1.

  The above-described processing conditions are examples, and the setting conditions differ depending on the type of sample, the amount of protrusion, the energy of the ion beam, and the like. Alternatively, the initial protrusion amount may be set to 0 μm, and the sample 6 may be moved from the start of processing.

  FIG. 8D shows a state where the cross-section preparation position C has moved to P1 and the cutting with the ion beam IB has been performed, and the cross-section preparation has been substantially completed.

(Embodiment 2)
FIG. 2 is a side view showing the main part of the sample preparation apparatus 200 according to the present invention. In the sample preparation apparatus 200, reference numeral 24 denotes a piezo motor for moving the shielding material holding mechanism 33 that holds the shielding material 32 by a minute amount in the y-axis direction. Reference numeral 23 denotes a control device for controlling the piezo motor 24, and 20 denotes a control arithmetic device such as a personal computer.

  A process of preparing a sample cross section using the sample preparation apparatus 200 configured as shown in FIG. 2 will be described with reference to FIG.

  FIG. 9A shows a cross-section of the edge of the shielding material 32 in a state where the processing chamber 18 of the sample preparation apparatus 200 is opened to the atmosphere as shown in FIG. 6A before the sample is irradiated with the ion beam. It is a side view which shows the state when set to the position C (middle of the foreign material 30). While observing the surface of the sample 6 using the optical microscope 15, the shielding material holding mechanism 33 that holds the shielding material 32 is moved by the shielding material position adjusting mechanism 10 to position the shielding material 32. FIG. 9A shows a state in which the position S1 on the Y-axis of the edge portion of the shielding material 32 is set so that a cross section of the foreign material 30 in the sample 6 is produced. The position of S1 is the cross-section production position C. The control arithmetic unit 20 stores the coordinates of S1.

  Since the protruding portion of the sample 6 that is not shielded by the shielding material 32 is too long, the shielding material holding mechanism 33 is driven by the piezo motor 24 to move the shielding material 32 by the distance d in the positive direction of the Y axis. Reduce the unshielded part. S2 is the initial position of the edge of the shielding member 32 at the start of processing. FIG. 9B shows a state in which the protruding portion is set short when ion beam irradiation is started on the sample. When the control arithmetic device 20 stores the coordinates of S1 and S2, the processing chamber 18 of the sample preparation device 200 is evacuated to the state shown in FIG. 6B.

  When the processing chamber 18 reaches a predetermined degree of vacuum, irradiation of the sample with the ion beam IB is started. As the cutting of the protruding portion of the sample 6 proceeds, the control arithmetic device 20 drives the shielding material holding mechanism 33 by the piezo motor 24, and gradually moves the edge of the shielding material 32 from S2 to S1. FIG. 9C shows a state in which the edge portion of the shielding member 32 is at the position S3 in the middle of moving from the position S2 to the position S1.

  For example, if the protrusion amount is set to 25 μm first, the cutting is performed without moving the shielding material in the state shown in FIG. 9B for about 20 minutes from the start of processing. When the machining time is between 20 minutes and 95 minutes, the edge of the shielding material 32 is moved continuously or intermittently in the direction in which the cutting of the protruding portion proceeds at a speed of about 1 μm / minute (FIG. 9C). State shown). During the period from 95 minutes to 120 minutes (end of processing), the movement of the shielding material 32 is stopped, and the cutting with the ion beam IB is performed while the edge portion of the shielding material 32 is fixed to S1.

  The above-described processing conditions are examples, and the setting conditions differ depending on the type of sample, the amount of protrusion, the energy of the ion beam, and the like. Further, the initial protrusion amount may be set to 0 μm, and the end edge portion of the shielding member 32 may be moved from the start of processing.

  FIG. 9D shows a state in which the edge of the shielding material 32 has moved to S1 (that is, the cross-section production position C) and cutting has been performed by the ion beam IB, and the cross-section production has been substantially completed.

(Embodiment 3)
FIG. 3 is a side view showing the main part of the sample preparation apparatus 300 according to the present invention. The sample preparation apparatus 300 is characterized in that the shielding material 12 (first shielding material) and the shielding material 32 (second shielding material) are formed separately and have a double structure. Reference numeral 24 denotes a piezo motor for moving the shielding material holding mechanism 33 for holding the shielding material 32 by a minute amount in the y-axis direction. Reference numeral 23 denotes a control device for controlling the piezo motor 24, and 20 denotes a control arithmetic device such as a personal computer.

  A process of preparing a sample cross section using the sample preparation apparatus 300 configured as shown in FIG. 3 will be described with reference to FIG.

  FIG. 10A shows a cross-section of the edge of the shielding material 12 in a state where the processing chamber 18 of the sample preparation apparatus 300 is opened to the atmosphere as shown in FIG. 6A before the sample is irradiated with the ion beam. It is a side view which shows the state when set to the position C (middle of the foreign material 30).

While observing the surface of the sample 6 using the optical microscope 15, the shielding material holding mechanism 13 that holds the shielding material 12 is moved by the shielding material position adjusting mechanism 10 to position the shielding material 12. FIG. 10A shows a state in which the position S1 on the Y-axis of the edge portion of the shielding material 12 is determined so as to produce a cross section of the foreign material 30 in the sample 6. FIG. The position of S1 is the sample preparation position C. The control arithmetic unit 20 stores the coordinates of S1.
During the above operation, the edge of the shielding member 32 is shifted to an appropriate position T1 where the edge of the shielding member 12 does not interfere with observation by the optical microscope 15.

  Since the protruding portion of the sample 6 that is not shielded by the shielding material 12 is too long as it is, the shielding material holding mechanism 33 is driven by the piezo motor 24, and the shielding material 32 is moved from S1 in the positive direction of the Y axis by a distance d to T2. It sets and makes the part which is not shielded by the shielding material 32 small. The control arithmetic unit 20 stores the coordinates (position) of T2. T2 is the initial position of the edge of the shielding member 32 at the start of processing. FIG. 10B shows a state in which the protruding portion is set short when ion beam irradiation is started on the sample.

  When the control arithmetic unit 20 stores the coordinates (positions) of S1 and T2, the processing chamber 18 of the sample preparation apparatus 300 is evacuated to the state shown in FIG. 6B.

  When the processing chamber 18 reaches a predetermined degree of vacuum, irradiation of the sample 6 with the ion beam IB is started. The control arithmetic unit 20 drives the shielding material holding mechanism 33 by the piezo motor 24 as the cutting of the protruding portion of the sample 6 proceeds, and gradually (continuously or intermittently) the edge of the shielding material 32. Move (retract) from T2 toward S1. FIG. 10C shows a state in which the edge of the shielding member 32 is at a position T3 in the middle of moving from T2 to S1.

  For example, if the protruding amount of the sample with respect to the shielding material 32 is first set to 25 μm, the edge portion of the shielding material 32 is not moved in the state shown in FIG. Cut. If the cutting speed is, for example, about 1 μm / min, most of 25 μm of the protruding portion is cut in 20 minutes. Thereafter, during the machining time of 20 minutes to 95 minutes, the edge of the shielding material 32 is moved (retracted) continuously or intermittently in the direction in which the cutting of the protruding portion proceeds at a speed of about 1 μm / minute (FIG. 10). (State shown in (c)). During the period from 95 minutes to 120 minutes (end of processing), the edge of the shielding material 32 is gradually moved to the position of S1. Before processing is completed, the edge of the shielding material 32 is moved to T4, and the position of the shielding material 32 and the shielding material 12 is fixed. For a while, the ion beam using the edge of the shielding material 12 is used. Finish cutting with IB. At this time, the position T4 of the edge portion of the shielding material 32 may be at an appropriate position that does not hinder the irradiation of the edge position S1 of the shielding material 12 by the ion beam IB.

  In FIG. 10D, after the edge portion of the shielding material 32 has moved to T4, the cutting is performed by the ion beam IB to the edge position S1 of the shielding material 12 (that is, the cross-section production position C). Indicates a completed state. Since the ion beam IB has an intensity distribution in which the center of the beam has the highest intensity and the intensity decreases with increasing distance from the center, it is preferable that the edge of the shielding material contributing to cutting is always located at the center of the beam. . Therefore, as can be seen from the fact that the edge of the shielding material 32 is located at the beam center position of the ion beam IB in FIG. 10B, the sample 6 is obtained using the sample stage 4 in accordance with the retreat of the shielding material 32 relative to the sample. The sample holder 7, the shielding material 12, and the shielding material 32 are integrally moved in a direction approaching the center of the ion beam IB so that the edge of the shielding material 32 is always at the beam center position of the ion beam IB. Yes.

  Then, at the time when the end edge portion of the shielding material 32 is retracted beyond the end edge portion of the shielding material 12, as shown in FIG. 10C, the edge portion of the shielding material 12 is the ion beam IB. The movement by the sample stage 4 is stopped in the state where the beam is located at the center of the beam, and finishing cutting using the edge of the shielding material 12 is performed.

  The above-described processing conditions are examples, and the setting conditions differ depending on the type of sample, the amount of protrusion, the energy of the ion beam, and the like. Further, the protruding amount of the sample with respect to the first shielding material 32 may be set to 0 μm, and the edge portion of the shielding material 32 may be moved from the start of processing.

  Furthermore, in the above description, the shielding material 32 has its edge at the positions of S1 and T4 after passing through T2 (the state shown in FIG. 10B) from the start time T3 (the state shown in FIG. 10C). However, the movement may be stepwise and the number of movements may be only one. That is, as described above, as a result of cutting without moving the edge portion of the shielding material 32 in the state shown in FIG. 10B for about 20 minutes from the start of machining, most of the protruding portion is obtained. Is cut back so that the end surface of the shielding material 32 passes through the edge position S1 of the shielding material 12 and reaches the position shown in FIG. 12 may be irradiated with the edge and the sample, and thereafter, cutting may be performed by the ion beam IB using the edge of the shielding material 12 in that state. If the amount of protrusion of the sample with respect to d and the shielding material 32 is set to be smaller than the cutable limit length determined by the diameter of the ion beam IB, the shielding material 32 in a state where the shielding material 12 is covered with such a shielding material 32. The cross-section preparation is completed by two steps of first-stage cutting using the end face of the first and second-stage finish cutting using the end face of the shielding material 12 with the shielding material 32 retracted from the shielding material 12. Can be made. Since the shielding material 32 has only to be moved between two positions of covering the shielding material 12 and retracting from the shielding material 12, the moving mechanism and the movement control can be simplified.

  Further, the first-stage cutting using the end face of the shielding material 32 is rough cutting, so it may be rough cutting. Therefore, for example, by setting the ion acceleration voltage higher than that during finish cutting, the cutting speed can be increased and the total time required for sample preparation can be shortened.

  Furthermore, even when performing the two-stage cutting as described above, the end face of the shielding material 32 is at the beam center position of the ion beam IB during the first-stage cutting, and during the second-stage finish cutting. The sample 6, the sample holder 7, the shielding material 12, and the shielding material 32 are preferably moved relative to the ion beam IB so that the edge of the shielding material 12 is at the beam center position of the ion beam IB. .

  In the description of the first to third embodiments, the example in which the piezo motor is used to move the sample or the shielding material has been described, but another motor may be used.

  As described above, according to the present invention, when producing a cross-sectional sample by irradiating the sample with the ion beam, the influence of redeposition in which the material scraped by the ion beam reattaches to the shielding material or the sample is removed. Thus, it is possible to provide a sample manufacturing apparatus and a sample manufacturing method for manufacturing a flat sample cross section without a step or dirt.

IB: ion beam q, r: axis Oi parallel to x axis ... ion beam irradiation axis OL ... optical axis 1 ... vacuum chamber 2 ... ion gun 3 ... sample stage extraction mechanism 4 ... sample stage 5 ... sample position adjusting mechanism 6 ... Sample 7 ... Sample holder 10 ... Shielding material position adjusting mechanism 11 ... Shielding material tilting mechanism 12, 32 ... Shielding material 13, 33 ... Shielding material holding mechanism 14 ... Optical microscope tilting mechanism 15 ... Optical microscope 16 ... Optical microscope position adjusting mechanism 17 ... Exhaust device 18 ... Processing chamber 20 ... Control arithmetic unit 21, 23 ... Piezomotor control device 22,24 ... Piezomotor

Claims (4)

A part of the sample is covered with a shielding material, and the shielding material of the sample is shielded by irradiating the sample with an ion beam from the ion beam irradiation means from the shielding material side including the edge of the shielding material. A sample cross-section preparation device for cutting a portion to be cut by the ion beam to produce a cross-section of the sample,
A first shielding material whose edge is set at the cross-section production position of the sample;
A second shielding material disposed between the first shielding material and the ion beam irradiation means so that the ion beam is not irradiated to an edge of the first shielding material and a cross-sectional preparation position of the sample; A second shielding material having an edge, and the ion beam from the ion beam irradiating means being irradiated to the cutting target portion of the sample and the second shielding material including the edge;
Second shielding material position moving means for moving the second shielding material to a retracted position where the ion beam is irradiated to an edge portion of the first shielding material and a cross-sectional preparation position of the sample;
An apparatus for preparing a cross section of a sample, comprising: A second shielding material position control means for controlling the second shielding material position moving means, wherein the second shielding material position control means is arranged such that an edge portion of the first shielding material is arranged at a cross-section preparation position of the sample; When the irradiation of the ion beam is started in a state where the cross-section creation position of the sample and the portion to be cut are shielded by the second shielding material, the reference position information is stored. Based on the information, as the cutting of the portion of the sample that is not shielded by the second shielding material proceeds, the second shielding material is moved so that the edge of the second shielding material approaches the reference position, When the edge portion of the second shielding material exceeds the reference position and the ion beam is irradiated to the edge portion of the first shielding material and the portion not shielded by the first shielding material, the second shielding material is used. I will stop moving the shield. Sample section preparation apparatus according to claim 1, wherein <br/> controlling the second shielding member position moving means. Covering a part of the sample with a shielding material, and irradiating the sample with an ion beam from the shielding material side including the edge of the shielding material, thereby cutting the portion of the sample that is not shielded by the shielding material. A sample cross-section preparation method for cutting by an ion beam to prepare a cross-section of the sample,
A first step of arranging an edge portion of the first shielding material at a cross-section preparation position of the sample before the ion beam irradiation;
Before the ion beam irradiation, the cross-section creation position of the sample and the portion to be cut are shielded by the second shielding material disposed between the first shielding material and the ion beam irradiation means. 2 a second step of setting a relative position between the shielding material and the sample;
A third step of cutting a portion to be cut that is not shielded by the second shielding material of the sample by the ion beam irradiation;
After the third step, the edge of the first shielding material is not shielded by the second shielding material, and the second shielding material is placed at a position where the ion beam is irradiated to the cross-section preparation position of the sample. A fourth step of arranging the ion beam irradiation,
A method for preparing a cross-section of a sample, comprising : In the third step, the position of the edge of the second shielding material relative to the sample is changed in the direction in which the cutting proceeds as the cutting of the portion of the sample that is not shielded by the second shielding material proceeds. samples sectional manufacturing method according to claim 3, characterized in that so as to.

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