JP2003114181A - Scanning probe microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scanning probe microscope which can prevent a large load from being applied to an X-Y scanner and a Z-axis fine-adjustment support member when a sample is observed. SOLUTION: The scanning probe microscope is provided with a sample holder device (H), a transparent cantilever holding member (26) used to hold a cantilever (31), a support (27) used to support the member (26), the Z-axis fine- adjustment support member (12) used to support the device (H) so as to be capable of being fine-adjusted in the Z-axis direction, the X-Y scanner (11) used to support the device (H) so as to be capable of being scanned inside the X-Y plane, a scanner holding member (9) used to support the device (H), the member (12) and the X-Y scanner (11), elastic members (16, 56) installed at the end part of the member (9), a packing sheet (51) and a fluid filling and discharge part (34).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning probe microscope used for scanning the surface of a sample and observing the three-dimensional shape of the sample surface with high resolution.

[0002]

2. Description of the Related Art AFM (Atomic Force Microscope), FFM (Friction Force Microscope)
, A friction force microscope) and the like have a feature that information on the shape of the surface of the sample can be obtained with high resolution. Furthermore, since the sample surface can be observed in a liquid and the degree of freedom of the measurement environment is high, its application field is wide. In particular,
Atomic force microscopes are capable of observing insulator samples, and are rapidly gaining popularity after their development. Examples of observation in the above liquid include observation of a biological sample while protecting it, observation of the state of electrolytic deposition on the surface of an inorganic material, and etching process, and use of liquid of ultrapure water or oil. There is a case where the sample surface is observed by obtaining a clean environment instead of vacuum. The following technology (J01) is conventionally known for an atomic force microscope when observing in such a liquid.

(J01) (Technology shown in FIGS. 5 to 7) FIG. 5 is an explanatory view of a conventional scanning probe microscope in a state of being observed in a liquid. FIG. 5A is a sectional view of a main part and FIG.
It is an enlarged view of the click lever shown in A. FIG. 6 is an enlarged view of a main part of FIG. 7A and 7B are explanatory views for explaining a method of sealing the sample space in which the sample is installed, FIG. 7A is a diagram showing a state in which the sample space is open, and FIG. 7B is a view just before the sample space is sealed. FIG. 7C is a diagram showing a state in which the sample space is completely sealed.

An upper opening 03 is formed on the upper surface of a cylindrical outer cylinder 01 of the scanning probe microscope. A vertical movement device (Z-axis direction drive device) not shown in the outer cylinder 01
An elevating stage 07 is arranged so as to be movable up and down. A horizontal shifter support surface 07a is formed on the upper end surface of the elevating stage 07, and a shifter 08 is supported on the horizontal shifter support surface 07a. The shifter 08 is movable in a horizontal plane and has an opening formed in the center thereof. A holder device holding member 0 having a cylindrical shape with a bottom is provided in the opening.
9 are accommodated. A cylindrical scanner is supported on the inner bottom surface of the holder device holding member 09, and the cylindrical scanner has an XY scanner 011 and a Z-axis fine movement supporting member 012 configured by a piezoelectric element. The XY scanner 011 is a member that scans in a horizontal XY plane (horizontal plane). The Z-axis fine movement support member 012 is a member that scans in the Z-axis direction (vertical direction).

A holder fixing base 013 is provided above the Z-axis fine movement supporting member 012. A packing support member 014 is placed on the upper side of the holder fixing base 013. A ring-shaped packing holding portion 014a is formed by projecting upward from the peripheral edge of the packing support member 014. A ring-shaped packing 016 is held by the packing holding portion 014a. In addition, the packing support member 01
A sample support base 018 made of resin is placed at the center of 4 via a packing 017. Then, the sample support base 0
18, packing 017 and packing support member 014
However, the fixing screw 019 is screwed to the holder fixing base 013 via the packing 021. An observation sample 022 (for example, a sample in medical, corrosion, biological field, etc.) is placed on the upper side of the sample support base 018 and the fixing screw 019.
The sample 022 is covered with a cap 023 having an opening in the center. The cap 023 is screwed and attached to the sample support base 018. The holder fixing base 013, the sample support base 018, the fixing screw 019, the cap 023 and the like constitute a sample holder device 0H.

On the upper side of the outer cylinder 01, there is arranged a ring-shaped support 027 for supporting the glass plate 026, which is a transparent cantilever holding member, in the central portion. Glass plate 02
A cantilever 031 having a probe at its tip is attached to the lower surface of 6 via a mounting base 029. Then, the packing 016 held by the packing support member 014 is moved away from the support 027 from the state shown in FIG. After the state shown in FIG. 7B in contact with the lower surface, the packing 016 is pressure-bonded to the lower surface of the support body 027 as shown in FIG. 7C. Then, the space between the glass plate 026 and the sample 022 becomes a sealed sample space 033. Furthermore, the probe 031a of the cantilever 031 fixed to the lower surface of the glass plate 026 by the raising of the elevating stage 07.
(See FIG. 5B) approaches the surface of the sample 022 to be observed. A fluid filling / discharging portion 034 for pouring / draining liquid into / from the sample space 033 is formed on the support 027.
The fluid filling / discharging section 034 is connected to a pump (not shown).

An optical system 042 composed of a laser light source 037, a first reflecting member 038, a second reflecting member 039 and a photodetector 041 is arranged above the glass plate 026 and the support 027.

When observing the sample in the liquid with the AFM, the liquid is filled in the upper end surface or the periphery of the sample 022. That is, as shown in FIGS. 5, 6 and 7C,
The glass plate 02 is placed inside the sealed sample space 033.
Cantilever 031 and sample support 01 fixed to No. 6
A sample 022 fixed to 8 is arranged, and a liquid such as ultrapure water is injected into the sample space 033 from the fluid filling / discharging section 034.

In this state, the laser light L emitted from the laser light source 037 is emitted toward the upper surface of the cantilever 031. The irradiated laser light L is reflected by the cantilever 031 and then enters the photodetector 041 through the second reflecting member 039. The probe is an XY scanner 0
The surface of the sample 022 is scanned in the X and Y directions by 11. At this time, if the surface of the sample 022 and the probe are separated from each other by a certain distance or approached, the tip of the probe moves downward or upward. When the position of the tip of the probe changes, the cantilever 031 is displaced, and the incident position of the laser beam L reflected by the cantilever 031 on the photodetector 041 changes. The photodetector 041 detects the change in the incident position and is fed back to the detection signal to drive the Z-axis fine movement supporting member 012 so that the change in the incident position does not occur. That is, the Z-axis fine movement supporting member 012 adjusts the position of the sample 022 in the vertical direction (Z-axis direction) so that the distance between the surface of the sample 022 and the probe is kept constant by the drive voltage. Therefore, the image of the surface of the sample 022 can be observed by image-processing the change in the drive voltage applied to the Z-axis fine movement supporting member 012.

[0010]

In the conventional (J01) technique, when observing the sample, the packing 016 of the sample holder device 0H is pressed against the lower surface of the support 027 so as to be in close contact therewith. Therefore, the sample holder device 0H
A load is applied to the XY scanner 011 and the Z-axis fine movement support member 012 that support the. At the time of observing the scanning image, if the sample is moved by a few microns or less by the XY scanner 011 and the Z-axis fine movement support member 012, the flexibility of the packing 016 allows fine movement and absorbs an excessive force due to the movement. There is no hindrance. However, in order to perform the observation in the range exceeding several tens of microns, it is necessary to slide the packing 016 with respect to the support 027 and move the packing 016. However, the packing 016
Is closely attached to the support 027 by pressing, and thus the packing 016 is moved in this manner by using the XY scanner 011 and the Z-axis fine movement supporting member supporting the packing 016 via the sample holder device 0H. An unreasonable force is applied to 012 in the lateral (XY) direction,
The Y scanner 011 and the Z-axis fine movement support portion 012 may be damaged, which is not preferable.

Therefore, in order to prevent the load from being applied when the XY scanner 011 and the Z-axis fine movement supporting portion 012 move to the observation position exceeding several tens of microns as described above, the packing 016 is attached to the support body 027. You must weaken the pressing force that is applied so that they come into close contact. In order to weaken the pressing force, it is necessary to lower the elevating stage 07 sufficiently, but if the elevating stage 07 is lowered, the seal becomes incomplete and liquid leakage occurs. For this reason, when moving over several tens of microns without applying a load,
The liquid once injected into the sample space 033 must be discharged to separate the support 027 and the packing 016 and move the sample 022. Then, the elevating stage 07 is again raised to bring the packing 016 into close contact with the support 027, and then the liquid has to be injected into the sample space 033.
There has been a problem that a moving operation exceeding several tens of microns without applying an unreasonable force to the shaft fine movement supporting portion 012 is troublesome.

In view of the above problems, the present invention has the following contents (O01) as a technical subject. (O01) To provide a scanning probe microscope capable of preventing a large load from being applied to an XY scanner and a Z-axis fine movement supporting member at the time of observing a sample.

[0013]

The scanning probe microscope of the present invention comprises a sample holder device (H) for holding a sample (22).
And the sample (2) held by this sample holder device (H).
2) and a transparent cantilever holding member (26) arranged at intervals in the Z-axis direction, and a cantilever (31) held by the cantilever holding member (26) and having a probe at its end. ), A support (27) for supporting the cantilever holding member (26), and a Z-axis fine movement support for finely supporting one of the sample holder device (H) and the cantilever (31) in the Z-axis direction. Member (1
2), an XY scanner (11) that supports any one of the sample holder device (H) and the cantilever (31) so that the sample holder device (H) and the cantilever (31) can be scanned within an XY plane perpendicular to the Z axis, and the Z axis fine movement support member ( 12) and XY scanner (1
1) and a holder device holding member (9) for supporting at least one of the sample holder device (H) and the holder device holding member (9) on the cantilever holding member (26) or the support body (27). The holder device holding member (9) for sealing the space (33) between the cantilever holding member (26) and the sample holder device (H) when being pressed.
A flexible packing sheet (51) stretched between the sample holder device (H) and the cantilever holding member (2).
6) and a fluid filling and discharging section (34) for filling and discharging the fluid in the sealed space (33) between the sample holder device (H).

That is, in the scanning probe microscope of the present invention,
Regarding the configuration, the following three cases (C01) to (C03) can be considered. (C01) In the case where the holder device holding member (9) holds the sample holder device (H), the Z-axis fine movement supporting member (12) and the XY scanner (11). (C02) The holder device holding member (9) holds the sample holder device (H) and the Z-axis fine movement supporting member (12). (C03) In the case where the holder device holding member (9) holds the sample holder device (H) and the XY scanner (11).

In the scanning probe microscope of the present invention having the above-mentioned configuration (C01), when observing the sample (22) in the liquid, first, the holder device holding member (9).
Is pressed against the cantilever holding member (26) or the support (27), and the cantilever holding member (2
The space (33) between 6) and the sample holder device (H) is sealed. Then, a fluid such as ultrapure water is injected into the sealed space (33) from the fluid filling and discharging section (34). Then, in the state of being filled with the fluid, the sample holder device (H) is finely moved in the Z-axis direction by the Z-axis fine movement supporting member (12) and held by the probe of the cantilever (31) and the sample holder device (H). The XY scanner (11) scans in the XY plane perpendicular to the Z-axis while maintaining a constant Z-axis direction distance from the sample (22). That is, the drive voltage of the Z-axis fine movement support member (12) is adjusted so that the distance between the probe and the surface of the sample (22) in the Z-axis direction becomes constant. Thereby, the Z-axis fine movement supporting member (1
The driving voltage of 2) depends on the unevenness of the surface of the sample (22). Therefore, the XY scanner (1
The surface shape of the sample (22) can be known from the drive voltage of the Z-axis fine movement supporting member (12) which changes corresponding to the drive voltage of 1).

Since the holder device holding member (9) is pressed against the cantilever holding member (26) or the support body (27), an excessive force causes the XY scanner (11) and the Z-axis fine movement support member (12). ) Can be prevented.

Also in the scanning probe microscope having the above-mentioned (C02) structure, similarly to the case of (C01), a load is applied to the Z-axis fine movement supporting member (12) held by the holder device holding member (9). Can be prevented. Furthermore, the above (C03)
The scanning probe microscope having the above configuration can also prevent the XY scanner (11) held by the holder device holding member (9) from being loaded.

In the scanning probe microscope of the present invention, the cantilever is an elastic member (16, 56) provided at an end of the holder device holding member (9) and presses the packing sheet (51). Holding member (26)
A ring-shaped elastic member (16, 56) for sealing the space between the sample holder device (H) and the sample holder device (H) can be provided. In the scanning probe microscope having the above configuration, the ring-shaped elastic members (16, 56) provided at the end of the holder device holding member (9) are pressed against the cantilever holding member (26) or the support body (27). In this state, the space (33) between the cantilever holding member (26) and the sample holder device (H) is sealed. Therefore, the elastic member (1
6, 56) are arranged between the holder device holding member (9) and the cantilever holding member (26) or the support (27), an excessive force is applied to the XY scanner (11) and the Z-axis fine movement support. It can be prevented from joining the member (12).

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment) Next, a specific example (embodiment) of an embodiment of the present invention will be described with reference to the drawings. (Embodiment 1) FIG. 1 is an explanatory view of Embodiment 1 of the scanning probe microscope of the present invention. FIG. 2 is an explanatory diagram for explaining a method of sealing the sample space in which the sample is installed, and FIG.
2C is a diagram showing a state where the sample space is open, FIG. 2B is a diagram showing a state immediately before the sample space is sealed, and FIG. 2C is a diagram showing a state where the sample space is completely sealed. In the explanation of the first embodiment of the present invention shown in FIGS. 1 and 2, in FIG.
7 to 7, the same components as those of the conventional scanning probe microscope are denoted by reference numerals other than the first 0 used in FIGS. 5 to 7, and detailed description thereof is omitted. To do. In addition, the first embodiment is similar to the conventional outer cylinder 0.
1, the outer cylinder 1 corresponding to the lifting stage 07, the shifter 08, etc., the lifting stage 7, the shifter 8, etc. are provided, but they are not shown.

The scanning probe microscope of the first embodiment is not provided with the packing support member 014 and the packing 017 of the conventional scanning probe microscope shown in FIGS. A substantially circular flexible packing sheet 51 is provided so as to cover the upper end opening of the holder device holding member 9. Further, the packing 16 is arranged on the upper surface of the packing sheet 51 supported by the holder device holding member 9. A through hole through which the fixing screw 19 is inserted is formed in the center of the packing sheet 51, and the packing sheet 51 is sandwiched between the holder fixing base 13 and the sample supporting base 18 and attached to the sample holder device H. There is. The sample support 18 and the sample 22 are located above the packing sheet 51. The peripheral edge of the packing sheet 51 is sandwiched between the packing 16 and the holder device holding member 9 and fixed to the upper end of the holder device holding member 9. The packing sheet 51 is flexible as described above and is stretched with a margin, so that the XY scanner 11
Also, it hardly hinders the movement of the sample holder device H and the sample 22 by the Z-axis fine movement support member 12.

When observing a sample in a liquid with the scanning probe microscope constructed as described above, first, as shown in FIG. 2A, the holder device holding member 9 spaced below the support 27 is provided. 2C is moved up and down through the elevating stage 7 by a vertical movement device (not shown), the packing 16 at the upper end of the holder device holding member 9 comes into contact with the lower surface of the support body 27, and the state shown in FIG. Thus, the packing 16 is pressure-bonded to the lower surface of the support body 27. Then, the packing 16 and the packing sheet 51
As a result, the space between the glass plate 26 that is the cantilever holding member and the sample 22 becomes the sample space 33 that is hermetically sealed. Further, as the lifting stage 7 and the holder device holding member 9 are raised, the probe of the cantilever 31 fixed to the lower surface of the glass plate 26 approaches the surface of the sample 22 to be observed. Then, a liquid such as ultrapure water is injected into the sample space 33 from the fluid filling and discharging unit 34.

In this state, the laser beam L emitted from the laser light source 37 is emitted toward the upper surface of the cantilever 31 in the same manner as the conventional example shown in FIGS. The irradiated laser light L is reflected by the cantilever 31, passes through the second reflecting member 39, and enters the photodetector 41. The probe scans the surface of the sample 22 in the XY directions by the XY scanner 11. At this time, if the surface of the sample 22 and the probe are separated from each other by a certain distance or come close to each other, the tip of the probe moves downward or upward. When the position of the probe tip changes, the cantilever 31 is displaced, and the incident position of the laser beam L reflected by the cantilever 31 on the photodetector 41 changes. The photodetector 41 detects this change in the incident position and is fed back to this detection signal to drive the Z-axis fine movement support member 12 so that the change in the incident position does not occur. Then, the image of the surface of the sample 22 can be observed by image-processing the change in the voltage applied to the Z-axis fine movement supporting member 12.

By the way, when observing the sample 22,
The packing 16 at the upper end of the holder device holding member 9 is pressed against the lower surface of the support body 27 so as to be in close contact therewith, and unlike the conventional example shown in FIGS. 5 to 7, the XY scanner supporting the sample holder device H. 11 and Z-axis fine movement support member 12
There is no undue force applied to. Therefore, even when the observation position is moved beyond several tens of microns, it is not necessary to weaken the pressing force applied so that the packing 16 is brought into close contact with the support 27. As a result, it is possible to prevent the sample space 33 from being incompletely sealed and from causing liquid leakage.

(Embodiment 2) FIG. 3 is an explanatory view of a scanning probe microscope of Embodiment 2. FIG. 3 of the second embodiment corresponds to FIG. 1 of the first embodiment. In the description of the second embodiment, constituent elements corresponding to those of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In the scanning probe microscope of the second embodiment, unlike the scanning probe microscope of the first embodiment, the peripheral edge of the packing sheet 51 is the packing 16 and the holder device holding member 9.
It is not sandwiched between and and is attached to the upper surface of the packing 16 attached to the upper end of the holder device holding member 9. Other configurations and operations are substantially the same as those of the scanning probe microscope of the first embodiment.

(Third Embodiment) FIG. 4 is an explanatory view of a scanning probe microscope according to a third embodiment. In the description of the third embodiment, constituent elements corresponding to those of the first and second embodiments are designated by the same reference numerals and detailed description thereof will be omitted.

Unlike the scanning probe microscope of the second embodiment, the scanning probe microscope of the third embodiment is provided with a resin bellows 56, which is an elastic member, instead of the packing 16 of the scanning probe microscope of the second embodiment. A pressing portion 56a made of an elastic material is formed on the upper end surface of 56. That is, the bellows 56 is attached to the upper end portion of the holder device holding member 9, and the peripheral edge portion of the packing sheet 51 is pressed and attached by the pressing portion 56 a on the upper end surface of the bellows 56. Other configurations and operations are almost the same as those of the scanning probe microscopes of the first and second embodiments.

The embodiment of the present invention has been described in detail above.
The present invention is not limited to the above embodiment,
Within the scope of the present invention as set forth in the claims,
Various changes can be made. Modifications of the present invention are exemplified below. (H01) In the scanning probe microscopes of the first to third embodiments, the central portion of the packing sheet 51 is the holder fixing base 1.
3 and the sample support 18 are sandwiched between them, but if they are attached to the sample holder device H, the mounting structure thereof can be appropriately changed. However, in consideration of replacement of the packing sheet 51 and the like, it is preferable that the central portion of the packing sheet 51 is attached by being sandwiched between the holder fixing base 13 and the sample support base 18. (H02) The ring-shaped elastic member provided on the upper end of the holder device holding member 9 may be a member other than the packing 16 and the bellows 56. (H03) The holder device holding member 9 may have a shape other than a cylinder. For example, a square tube is also possible. (H04) Sample holder device H by Z-axis fine movement support member 12
Instead of finely moving in the Z-axis direction, the cantilever 31 or the cantilever holding member 29 may be finely moved in the Z-axis direction. (H05) The sample holder device H is moved to X with the XY scanner 11.
Instead of scanning in the Y direction, the cantilever 31 or the cantilever holding member 29 can be configured to scan. (H06) When the peripheral edge of the packing sheet 51 is configured to have elasticity, the packing 16 and the bellows 5 are
6 can be omitted.

[0029]

According to the present invention, a ring-shaped elastic member is provided at the end of the holder device holding member, and a flexible packing sheet is stretched between the holder device holding member and the sample holder device. There is. Then, when the elastic member is pressed by the cantilever holding member or the support body that supports the cantilever holding member, the space between the cantilever holding member and the sample holder device is sealed by the elastic member and the packing sheet. . Therefore, when sealing the space, force is applied to the holder device holding member,
Almost no force is applied to the sample holder device, the XY scanner, and the Z-axis fine movement supporting member. As a result, when observing the sample, XY
It is possible to prevent a large load from being applied to the scanner and the Z-axis fine movement support member, and it is possible to smoothly operate the XY scanner and the Z-axis fine movement support member.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a scanning probe microscope according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining a method of sealing a sample space in which a sample is installed, FIG. 2A is a diagram showing a state in which the sample space is open, and FIG. 2B is a sample space sealed. FIG. 2C is a diagram showing a state immediately before being performed, and FIG. 2C is a diagram showing a state where the sample space is completely sealed.

FIG. 3 is an explanatory diagram of a scanning probe microscope according to a second embodiment.

FIG. 4 is an explanatory diagram of a scanning probe microscope according to a third embodiment.

5 is an explanatory view of a scanning probe microscope in a state of being observed in a conventional liquid, FIG. 5A is a sectional view of a main part, and FIG.
FIG. 5B is an enlarged view of the click lever shown in FIG. 5A.

6 is an enlarged view of a main part of FIG.

FIG. 7 is an explanatory diagram for explaining a method for sealing the sample space in which the sample is installed, FIG. 7A is a diagram showing a state where the sample space is open, and FIG. 7B is a sample space sealed. FIG. 7C is a diagram showing a state immediately before being performed, and FIG. 7C is a diagram showing a state where the sample space is completely sealed.

[Explanation of symbols]

H ... Sample holder device, 9 ... Holder device holding member, 11 ...
XY scanner, 12 ... Z-axis fine movement supporting member, 16 ... Packing (elastic member), 22 ... Sample, 26 ... Glass plate (cantilever holding member), 27 ... Support, 31 ... Cantilever, 3
3 ... Sample space, 34 ... Fluid filling / discharging part, 51 ... Packing sheet, 56 ... Bellows (elastic member).

Claims (2)

[Claims] 1. A sample holder device for holding a sample, a transparent cantilever holding member arranged facing the sample held by the sample holder device with a gap in the Z-axis direction, and the cantilever holding member. A cantilever that is held and has a probe at its end, a support that supports the cantilever holding member, and a Z-axis fine movement that finely supports one of the sample holder device and the cantilever in the Z-axis direction. An X that supports a supporting member and one of the sample holder device and the cantilever so that the sample holder device and the cantilever can be scanned within an XY plane perpendicular to the Z axis.
A Y scanner, a holder device holding member that supports the sample holder device and at least one of the Z-axis fine movement supporting member and the XY scanner, and the holder device holding member is pressed by the cantilever holding member or the support body. In this case, in order to seal the space between the cantilever holding member and the sample holder device, a flexible packing sheet stretched between the holder device holding member and the sample holder device, the cantilever holding member and the sample holder device, And a fluid filling / discharging unit for filling and discharging the fluid in the sealed space between the scanning probe microscopes. 2. An elastic member provided at an end portion of the holder device holding member, the ring-like elastic member pressing the packing sheet to seal a space between the cantilever holding member and the sample holder device. The scanning probe microscope according to claim 1, further comprising a member.