JP2003315239A - Scanner for spm - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scanner for SPM (scanning probe microscope) which is miniaturized without sacrificing displacement amount and which is suitable for a high-speed scanning operation having a high resonance frequency. <P>SOLUTION: The scanner 100 for SPM is provided with a cylindrical piezoelectric element 110 used to generate a displacement in the X-direction and the Y-direction; a stacked piezoelectric element 120 used to generate a displacement in the Z-direction; a connecting member 130 used to connect the piezoelectric element 110 to the piezoelectric element 120; a mounting member 140 fixed to the upper end of the piezoelectric element 110; and a cantilever support member 150 fixed to the lower end of the piezoelectric element 120. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to, for example, STM.
(Scanning tunneling microscope) and AFM (atomic force microscope)
The present invention relates to SPM (scanning probe microscope) represented by the above.

[0002]

2. Description of the Related Art An SPM (scanning probe microscope) for measuring and analyzing the undulating shape of a sample in nano-order by scanning the sample with a probe typified by a cantilever is widely known. In recent years, there has been an increasing need for miniaturization of the SPM itself, including usability. Among them, the downsizing of the scanning mechanism for scanning the probe, that is, the scanner is essential. Such SPM scanners include JP-A-2000-350478 and JP-A-8-
As disclosed in Japanese Patent No. 271212, a configuration using a cylindrical piezoelectric element or a laminated piezoelectric element is widely adopted.

FIG. 6 shows a so-called tube scanner using a cylindrical piezoelectric element.

In FIG. 6, a tube scanner 500 is provided.
Is composed of a cylindrical piezoelectric body 502 and electrodes provided on the inner peripheral surface and the outer peripheral surface thereof. Probe 53
0 is attached to the lower end or free end of the tube scanner 500.

The tube scanner 500 is roughly
It is divided into an XY displacement portion 510 that generates an XY displacement and a Z displacement portion 520 that generates a Z displacement.

The XY displacement portion 510 is a cylindrical piezoelectric body 50.
One common electrode 512 provided on the inner peripheral surface of the second piezoelectric element 502, a pair of X drive electrodes 514 and a pair of Y drive electrodes 516 provided on the outer peripheral surface of the cylindrical piezoelectric body 502. The X drive electrodes 514 and the Y drive electrodes 516 are alternately arranged at equal intervals.

The XY displacement section 510 includes a pair of X drive electrodes 5
In response to the application of the reverse polarity voltage to the piezoelectric element 14, the piezoelectric body 502 located at that portion bends, causing an X displacement. As a result, the probe 530 is moved or scanned in the X direction. Similarly, the XY displacement portion 510 causes Y displacement by bending the piezoelectric body 502 located in that portion in response to the application of a reverse polarity voltage to the pair of Y drive electrodes 516. This causes the probe 530 to move or scan in the Y direction.

The Z displacement section 520 is a cylindrical piezoelectric body 502.
It has one common electrode (not shown) provided on the inner peripheral surface thereof and one Z drive electrode 524 provided on the outer peripheral surface of the cylindrical piezoelectric body 502. Z displacement section 520
Causes Z displacement in response to voltage application to the Z drive electrode 524. As a result, the probe 530 is moved or scanned in the Z direction.

A scanner using a laminated piezoelectric element, a so-called tripod scanner, is shown in FIG.

In FIG. 7, the tripod scanner 60 is shown.
0 is a laminated piezoelectric element 610 for X displacement that generates X displacement.
And a multilayer piezoelectric element 620 for Y displacement that generates Y displacement
And a Z displacement laminated piezoelectric element 630 for generating Z displacement. X displacement multilayer piezoelectric element 610, Y displacement multilayer piezoelectric element 620, and Z displacement multilayer piezoelectric element 63.
0s are connected so as to be orthogonal to each other.

A laminated piezoelectric element 610 for X displacement, a laminated piezoelectric element 620 for Y displacement, and a laminated piezoelectric element 630 for Z displacement.
Each of which is configured by alternately stacking a plurality of piezoelectric bodies and a plurality of electrodes in one direction, and in accordance with the voltage application to the electrodes,
It expands and contracts in the stacking direction, that is, it causes displacement.

The probe 640 is attached to the lower end, that is, the free end of the Z displacement multilayer piezoelectric element 630.
The X-displacement laminated piezoelectric element 610 causes X-displacement in response to the voltage application, whereby the probe 640 is moved or scanned in the X-direction. The Y displacement multi-layer piezoelectric element 620 causes Y displacement in response to the voltage application, which causes the probe 64 to move.
0 is scanned in the Y direction. Multilayer piezoelectric element for Z displacement 63
0 causes Z displacement in response to voltage application, which causes the probe 640 to scan in the Z direction.

[0013]

The scanner preferably has a high resonant frequency for high speed scanning. To that end, it is generally good for the scanner to be small.

It is difficult to downsize any of the above-mentioned scanners while maintaining the current displacement amount, that is, the stroke.

In a so-called tube scanner using a cylindrical piezoelectric element, XY displacement is generated by tilting displacement. Therefore, in principle, the diameter of the cylinder is reduced so that the tilt angle generation point is brought closer to the center of the cylinder. ,
It is possible to shorten the cylindrical piezoelectric element without impairing the displacement amount of the XY displacement. However, since the Z displacement amount does not depend on the cylinder diameter and simply depends on the length of the cylindrical piezoelectric element, it is impossible to shorten the cylindrical piezoelectric element without impairing the Z displacement amount.

A scanner using a laminated piezoelectric element, a so-called tripod scanner, can generate a sufficient displacement in the Z direction in the same size as a tube scanner, but in the X and Y directions. A displacement of sufficient magnitude cannot be generated.
A method using a well-known magnifying mechanism having a complicated shape such as a spring stage may be considered in order to obtain a sufficient displacement in the X direction and the Y direction, but this makes the scanner expensive and Lateral size of magnifying mechanism (X
It is technically difficult to keep the (direction and Y-direction size) within the outer diameter of the tube scanner.

An object of the present invention is to provide a downsized SPM scanner without sacrificing displacement.

[0018]

The SPM scanner of the present invention comprises a cylindrical piezoelectric element that is displaced in the XY directions and a laminated piezoelectric element that is displaced in the Z direction. The laminated piezoelectric elements are integrated in series in the Z direction.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

First embodiment The SPM scanner of the first embodiment of the present invention is shown in FIG.

As shown in FIG. 1, the SP of this embodiment
The M scanner 100 includes a cylindrical piezoelectric element 110 that is displaced in the XY directions and a laminated piezoelectric element 120 that is displaced in the Z directions. The cylindrical piezoelectric element 110 and the laminated piezoelectric element 120 are integrated in series in the Z direction.

More specifically, the cylindrical piezoelectric element 110 and the laminated piezoelectric element 120 are connected to each other via a connecting member 130. A mounting member 140 is fixed to the upper end of the cylindrical piezoelectric element 110. Mounting member 140
Has a mounting screw 142 for mounting on a frame or the like. At the lower end of the laminated piezoelectric element 120, a cantilever support member 1
50 is fixed. A cantilever 160 is detachably attached to the cantilever support member 150.
The cantilever 160 has a probe 162 and a lever 164 that supports the probe 162 at its free end.

That is, the SPM scanner 100 has the X
A cylindrical piezoelectric element 110 that is displaced in the Y direction, a laminated piezoelectric element 120 that is displaced in the Z direction, a connecting member 130 that connects the cylindrical piezoelectric element 110 and the laminated piezoelectric element 120 to each other, and a cylindrical piezoelectric element. An attachment member 140 fixed to the upper end of 110 and a cantilever support member 150 fixed to the lower end of the laminated piezoelectric element 120 are provided.

The cylindrical piezoelectric element 110 is provided with a cylindrical piezoelectric body 112 and an inner peripheral surface thereof (not shown).
One common electrode and a pair of Xs provided on the outer peripheral surface thereof
A drive electrode 116 and a pair of Y drive electrodes 118 are provided. The common electrode extends over almost the entire inner peripheral surface of the cylindrical piezoelectric body 112. Both the X drive electrode 116 and the Y drive electrode 118 have the same size. The pair of X drive electrodes 116 are arranged to face each other, and the pair of Y drive electrodes 118 are also arranged to face each other. The adjacent X drive electrodes 116 and Y drive electrodes 118 are arranged in the cylindrical piezoelectric body 112.
Are arranged at an angle of 90 ° with respect to the central axis.

The laminated piezoelectric element 120 has, for example, a prismatic shape, as is generally known. However, the laminated piezoelectric element 120 does not necessarily have a prismatic shape, and may have any other shape, for example, a cylindrical shape. In addition, the laminated piezoelectric element 120
Since the laminated piezoelectric element 120 is hung and used, it is generally considered that the laminated piezoelectric element 120 is preloaded by a spring material in consideration of the fact that the laminated piezoelectric element is strong in compression in the displacement direction but weak in tension. Good.

Cylindrical piezoelectric element 110 and laminated piezoelectric element 1
20 are both electrically connected to the controller with built-in amplifier 170.
Controlled by.

The cylindrical piezoelectric element 110 responds to the application of a reverse polarity voltage from the amplifier built-in controller 170 to the pair of X drive electrodes 116 or Y drive electrodes 118.
It is displaced in the X or Y direction. For example, when a voltage of opposite polarity is applied to the pair of X drive electrodes 116, one X
The piezoelectric body in the portion sandwiched between the drive electrode 116 and the common electrode expands, and conversely, the piezoelectric body in the portion sandwiched between the other X drive electrode 116 and the common electrode contracts. as a result,
The cylindrical piezoelectric element 110 is curved, and its free end is displaced in either of ± X directions. Further, when the polarities of the reverse polarity voltages applied to the pair of X drive electrodes 116 are reversed, the free end of the cylindrical piezoelectric element 110 is displaced in the direction opposite to the displacement direction described above. That is, the cylindrical piezoelectric element 1
10 is displaced in the ± X direction. As a result, the probe 162
Are displaced or scanned in the ± X directions. This also applies to the displacement in the Y direction.

The laminated piezoelectric element 120 extends in the Z direction in response to voltage application. In the initial state, the laminated piezoelectric element 120 is applied with a constant bias voltage from the controller 170 with a built-in amplifier. When the voltage applied to the laminated piezoelectric element 120 is changed, the laminated piezoelectric element 120 expands and contracts according to the polarity of the difference between the voltage applied to the laminated piezoelectric element 120 and the bias voltage. Therefore, the free end of the laminated piezoelectric element 120 is displaced in the ± Z direction. As a result, the probe 162 is displaced or scanned in the ± Z directions.

When measuring / analyzing the surface of the sample 180 to be measured / analyzed, the probe 162 moves the sample 18
It is located near the 0 surface. The probe 162 moves the sample 180 by the operation of the cylindrical piezoelectric element 110 described above.
The surface is moved in the XY directions, that is, XY scanning is performed. While the probe 162 is XY scanned, the probe 16
The displacement in the Z direction of 2 is monitored by the optical lever method, the optical interference method, the optical shutter method, the probe strain detection method, and the like. For example, the probe 162 is Z-scanned so that the position in the Z direction is kept constant.

Based on control signals for XY scanning and Z scanning,
Physical information on the surface of the sample 180, for example, unevenness on the surface of the sample 180 is measured and analyzed.

The SPM scanner 100 of this embodiment is
Since the cylindrical piezoelectric element for XY scanning and the laminated piezoelectric element for Z scanning are integrated in series in the Z direction, miniaturization is achieved without sacrificing the displacement amount, that is, the stroke. Therefore, the SPM scanner 100 has a high resonance frequency and is therefore suitable for high speed scanning.

Second Embodiment FIG. 2 shows an SPM scanner according to the second embodiment of the present invention.
In FIG. 2, members designated by the same reference numerals as the members of the first embodiment indicate equivalent members, and in the following description, detailed description thereof will be omitted to avoid duplication of description.

As shown in FIG. 2, the SP of this embodiment is
In the M scanner 200, the laminated piezoelectric element 120 has a through hole 222 extending in the Z direction. Connection member 130
Has an opening 232, which is a cylindrical piezoelectric element 11
The space 212 inside 0 is connected to the through hole 222 of the laminated piezoelectric element 120. The mounting member 140 has the opening 2
44, which connects the space 212 inside the cylindrical piezoelectric element 110 to the external space. The cantilever support member 150 has an opening 252, which connects the through hole 222 of the laminated piezoelectric element 120 to the external space.

The opening 244 of the mounting member 140, the space 212 inside the cylindrical piezoelectric element 110, and the connecting member 13
0 opening 232 and the through hole 22 of the multilayer piezoelectric element 120.
2 and the opening 252 of the cantilever support member 150,
Together, they form a cavity extending across the SPM scanner 200 in the Z direction.

The cavity extending over the entire SPM scanner 200 can be used as a space for securing an optical path. In other words, such a cavity allows the probe 162 and the sample 180 to be optically viewed by the lens 290 located above the SPM scanner 200.

The SPM scanner 200 of this embodiment is
In addition to the advantages of the first embodiment, since it has a cavity penetrating in the Z direction, it has the advantage that the probe 162 and the sample 180 can be optically observed through the cavity. There is.

Third Embodiment FIG. 3 shows an SPM scanner according to the third embodiment of the present invention.
In FIG. 3, members designated by the same reference numerals as the members of the second embodiment indicate the same members, and in the following description, detailed description thereof will be omitted to avoid duplication of description.

As shown in FIG. 3, the SP of this embodiment is
The M scanner 300A further includes a lens 390 arranged inside a cavity penetrating in the Z direction. Lens 3
90 is fixed to the opening 244 of the attachment member 140.

Preferably, the lens 390 is arranged so that its optical axis coincides with the central axis of the cavity, and the probe 162 is arranged so as to be located on the optical axis of the lens 390.

The SPM scanner 300A is attached to the objective revolver 306 of the optical microscope by the attaching screw 142 of the attaching member 140. Generally, the objective revolver 306 can support a plurality of objective lenses 304, and one of the plurality of objective lenses 304 attached to the objective revolver 306 can be selectively placed in the optical path of the optical microscope. SP
The M scanner 300A is attached to the objective revolver 306 instead of one of the objective lenses 304.

Lens 390 of SPM scanner 300A
Cooperates with an optical microscope that includes an objective revolver 306,
Through the cavity of the SPM scanner 300A, the probe 1
It is possible to optically observe 62 and the sample 180. In other words, the lens 390 of the SPM scanner 300A functions as the objective lens of the optical microscope including the objective revolver 306.

The SPM scanner 300A of this embodiment
Has a cavity therethrough and a lens 390 disposed therein and is attachable to an objective revolver of an optical microscope, which acts as an objective lens of the optical microscope. Therefore, in addition to the advantages of the second embodiment, the SPM scanner 300A of the present embodiment has the advantage that it is possible to optically observe the probe 162 and the sample 180 using an existing optical microscope. is doing. Thereby, the SPM including the observation optical system can be inexpensively constructed.

The SPM scanner 300A shown in FIG.
Then, the lens 390 is attached to the opening 244 of the mounting member 140.
However, the mounting position of the lens 390 is not limited to this, and may be arranged at any position inside the cavity of the SPM scanner. For example, in FIG.
The lens 390 may be fixed to the opening 232 of the connecting member 130, as in the SPM scanner 300B shown in FIG. Alternatively, the SPM scanner 3 shown in FIG.
The lens 390 may be fixed to the opening 252 of the cantilever support member 150, as in 00C. That is, the SPM scanner 300B shown in FIG. 4 and the SPM scanner 300C shown in FIG. 5 are also included in this embodiment.

Although the embodiments of the present invention have been described with reference to the drawings, the present invention is not limited to these embodiments, and various modifications and variations are possible without departing from the scope of the invention. Changes may be made.

[0045]

According to the present invention, a cylindrical piezoelectric element for XY scanning and a laminated piezoelectric element for Z scanning are integrated in series in the Z direction, so that the displacement amount is not sacrificed and the size is reduced. Provided is a scanner for SPM which has been achieved. Since the SPM scanner according to the present invention is small, it has a high resonance frequency and is therefore suitable for high speed scanning.

[Brief description of drawings]

FIG. 1 shows an SPM scanner according to a first embodiment of the present invention.

FIG. 2 shows an SPM scanner according to a second embodiment of the present invention.

FIG. 3 shows an SPM scanner according to a third embodiment of the present invention.

FIG. 4 illustrates another SPM scanner according to a third embodiment of the present invention.

FIG. 5 illustrates yet another SPM scanner according to a third embodiment of the present invention.

FIG. 6 shows a so-called tube scanner using a widely known cylindrical piezoelectric element.

FIG. 7 shows a so-called tripod scanner using a well-known laminated piezoelectric element.

[Explanation of symbols]

Scanner for 100 SPM 110 Cylindrical piezoelectric element 120 Multilayer piezoelectric element 130 Connection member 140 Mounting member 150 cantilever support member

Claims (3)

[Claims] 1. A scanner for an SPM (scanning probe microscope), comprising a cylindrical piezoelectric element that is displaced in the XY directions and a laminated piezoelectric element that is displaced in the Z direction. A scanner for SPM in which multilayer piezoelectric elements are integrated in series in the Z direction. 2. The laminated piezoelectric element according to claim 1, wherein
Has a through hole extending in the same direction, the through hole of the laminated piezoelectric element and the space inside the cylindrical piezoelectric element communicate with each other, and they cooperate to form a cavity extending in the Z direction over the entire SPM scanner. Forming the scanner for SPM. 3. The scanner for SPM according to claim 2, further comprising a lens disposed in the cavity.