JP2023087533A - Afm holder with vibration isolating mechanism - Google Patents

Abstract

To provide an AFM holder with a vibration isolating mechanism, which is a mechanism for exciting only a sensor mechanism without exciting the whole AFM holder, the mechanism obtaining a high vibration isolating effect to increase a Q value and also increasing frequency stability and further free from concerns such as abrasion.SOLUTION: An AFM holder includes sensor mechanisms 2a, 2b, 2c, and vibration isolating mechanisms 3a, 3b, 3c. The sensor mechanisms 2a, 2b, 2c include a probe 5 made to approach a sample surface S, and a vibration mechanism 4 that excites the probe 5. The vibration isolating mechanisms 3a, 3b, 3c include a plate 9 fixed adjacent to the sensor mechanisms 2a, 2b, 2c on the front side, and a cylindrical hollow pipe 10 fixed at a one point on the circumference thereof in a vertical sectional view on the back side of the plate 9.SELECTED DRAWING: Figure 1

Description

The present invention relates to an AFM holder with a vibration isolation mechanism used in an AFM (Atomic Force Microscope) atomic force microscope.

SPM (Scanning Probe Microscope) scanning probe microscope is a device that can observe the sample surface with a resolution of nanometer order or less, specifically, STM (Scanning Tunneling Microscope) scanning tunneling microscope, AFM (Atomic Force Microscope) atom force microscope, KFM (Kelvin Force Microscope) surface potential microscope, UHV (Ultra High Vacuum)-STM ultra-high vacuum scanning tunneling microscope, UHV (Ultra High Vacuum)-AFM ultra-high vacuum atomic force microscope, SNOM (Scanning Near -field Optical Microscope) scanning near-field optical microscope and the like.

When measuring in the FM-AFM mode of an AFM atomic force microscope (hereinafter referred to as AFM), a vibrating reed with a probe attached to the tip is brought close to the sample surface while vibrating at the resonance frequency, and the probe and the sample surface contact each other. The interaction force is detected as a frequency shift of the vibrating probe, and the sample surface shape is measured by scanning in the horizontal direction while feedback-controlling the distance between the probe and the sample surface so that the frequency shift is constant. Alternatively, a frequency shift image is measured by horizontal scanning with the probe fixed between samples.

Conventionally, when the probe is vibrated by a vibrator or piezoelectric element, etc., the piezoelectric element or the like is provided on the AFM head side, which is below the lower attachment/detachment surface of the AFM holder that supports the vibrating piece, and the entire AFM holder is excited. I was letting However, if the entire AFM holder is excited, the number of parts to be excited increases, so multiple vibration modes are likely to occur. The number of parts to be used increases, and the number of vibration modes increases accordingly. Even if the Q value is increased by anti-vibration isolation in an attempt to suppress the influence of these vibration modes, vibration cannot be transmitted and excitation cannot be performed. Since there is a trade-off relationship as described above, when the entire holder is excited, it has been necessary to allow a situation in which the vibration characteristics are unstable. Conventionally, even when a piezoelectric element or the like is provided on the AFM holder to excite only the sensor mechanism, there is no effective anti-vibration vibration isolation mechanism. There was a problem that the vibration characteristics fluctuated or were modulated.

In view of this, Patent Document 1 discloses an atomic force microscope that excites a vibrating bar without exciting the entire AFM holder in order to eliminate noise such as vibration characteristics of the AFM holder itself.

Japanese Patent Application Laid-Open No. 2006-153574

However, the atomic force microscope described in Patent Document 1 has a structure that does not vibrate the AFM holder by providing a rubber O-ring with a different acoustic impedance from the glass plate as a vibration insulating material on the glass plate that transmits vibration. However, the rubber O-ring converts the vibrational energy into thermal energy through internal friction while having a large contact area along the circumference. As a result, sufficient anti-vibration effect cannot be obtained, and the Q value cannot be increased. Furthermore, rubber and resin wear and deteriorate with use, causing vibration noise.

Therefore, the present invention has been made in view of the above-mentioned circumstances, and is intended to excite only the sensor mechanism without exciting the entire AFM holder. An object of the present invention is to provide an AFM holder with an anti-vibration mechanism that increases frequency stability and is free from wear and the like.

An AFM holder with a vibration isolation mechanism according to the present invention has a sensor mechanism and a vibration isolation mechanism. , wherein the vibration isolation mechanism comprises a plate fixed on the front side so as to be adjacent to the sensor mechanism, and a hollow columnar shape fixed on the back side of the plate at one point on the circumference in a vertical cross-sectional view. and a pipe.

Further, the sensor mechanism has a vibrating bar having a probe at its free end, and the hollow pipe is fixed to the plate with the axial direction of the hollow pipe being substantially perpendicular to the longitudinal direction of the vibrating bar. It is characterized by

Further, the vibration mechanism is a crystal oscillator, and the hollow pipe is fixed to the plate material with the axial direction of the hollow pipe being substantially perpendicular to the longitudinal direction of the crystal oscillator when viewed from the top. do.

Furthermore, the natural frequency of the bending vibration of the plate material in the longitudinal direction of the vibrating piece or the natural frequency of the bending vibration of the plate material in the longitudinal direction of the crystal oscillator when viewed from the top and the natural frequency of the bending vibration of the hollow pipe in the circumferential direction are different from each other.

Furthermore, the plate material is characterized by containing diamond.

Further, the sensor mechanism is characterized by comprising a sensor base containing a diamond adjacent to the vibrating mechanism.

According to the present invention, a sensor mechanism and an anti-vibration mechanism are provided, and the sensor mechanism includes a probe brought close to the sample surface and a vibration mechanism for exciting the probe. The vibration mechanism includes a plate fixed on the front side so as to be adjacent to the sensor mechanism, and a cylindrical hollow pipe fixed on the back side of the plate at one point on the circumference in a vertical cross-sectional view. Bending vibration and longitudinal vibration can be isolated and vibration-isolated, Q value can be increased, and AFM observation can be performed while maintaining frequency stability.

Further, the hollow pipe is fixed to the plate with the axial direction of the hollow pipe being substantially perpendicular to the longitudinal direction of the vibrating element. The hollow pipe can be fixed so as to be in point contact with respect to the vibrating direction of the vibrating bars, and the effects of vibration isolation and vibration isolation can be enhanced.

In addition, since the probe is attached to the crystal oscillator, which has a sufficiently large spring constant, the probe is prevented from coming into contact with the sample surface due to the atomic force. Since it is fixed to the plate in a direction that is substantially perpendicular to the direction of the crystal oscillator, the hollow pipe can be fixed so as to make point contact with the vibration direction of the crystal unit, and the effect of vibration isolation and vibration isolation is enhanced. be able to.

In addition, the natural frequency of the bending vibration of the plate material in the longitudinal direction of the vibrating piece or the natural frequency of the bending vibration of the plate material in the longitudinal direction of the crystal unit when viewed from the top and the natural frequency of the bending vibration of the hollow pipe in the circumferential direction Since the numbers and are different from each other, it is possible to suppress the propagation of bending vibration.

In addition, by including diamond in the plate material, bending vibration can be effectively isolated.

In addition, since the sensor mechanism has a sensor base containing diamond adjacent to the vibration mechanism, it is possible to effectively isolate bending vibration.

1 is a schematic side view of an AFM holder with an anti-vibration mechanism according to a first embodiment of the present invention, in which the vibration mechanism is an excitation piezo and the vibrating piece is a TF-type crystal oscillator; FIG. 1A is a schematic side view of an AFM holder with an anti-vibration mechanism according to a first embodiment of the present invention, in which the vibration mechanism is an excitation piezo and the vibrating bars are single-split tuning-fork crystal oscillators; FIG. (b) is a schematic side view of the AFM holder with vibration isolation mechanism according to the first embodiment of the present invention, in which the vibration mechanism is an excitation piezo, and the vibration piece is a semi-electrode crystal resonator. (a) It is a schematic perspective view showing a comb-shaped hollow pipe which is a modification of the hollow pipe. (b) It is a schematic side view of (a). FIG. 10 is a schematic perspective view showing an AFM holder with a vibration isolation mechanism according to a second embodiment of the present invention in which the vibration mechanism is an excitation piezo and the vibration piece is a cantilever optical lever system. FIG. 10 is a schematic side view showing an AFM holder with a vibration isolating mechanism according to a third embodiment of the present invention, in which the vibration mechanism is an LER type crystal oscillator; (a) It is a schematic perspective view showing the upper surface and the vibration direction of the LER crystal oscillator. (b) A schematic diagram showing the longitudinal direction of the upper surface, the axial direction of the hollow pipe, and the vibration direction. (a) is a schematic perspective view showing the top surface and the vibration direction of a TF crystal resonator. (b) A schematic diagram showing the longitudinal direction of the upper surface, the axial direction of the hollow pipe, and the vibration direction. (a) is a schematic vertical side view showing an AFM holder with an anti-vibration mechanism according to a third embodiment of the present invention in which the vibration mechanism is a TF-type crystal resonator. (b) A schematic side view showing an AFM holder with an anti-vibration mechanism according to a third embodiment of the present invention in which the vibration mechanism is a one-sided tuning fork crystal oscillator. (a) is a schematic side view showing an AFM holder with an anti-vibration mechanism according to a third embodiment of the present invention, in which the vibration mechanism is a shear force type crystal resonator. (b) A schematic side view showing an AFM holder with a vibration isolation mechanism according to a third embodiment of the present invention, in which the vibration mechanism is a semi-electrode crystal oscillator. (a) It is a schematic perspective view showing the AFM holder with a vibration isolation mechanism according to the first embodiment of the present invention when the sensor base is used in an upright position. (b) A schematic perspective view showing an AFM holder with a vibration isolation mechanism according to a third embodiment of the present invention when the sensor base is used in an upright position.

Hereinafter, the AFM holders 100, 200, 300 with anti-vibration mechanisms will be described in detail with reference to the drawings.

In this specification, vibration isolation means to confine the vibration generated in the system within the system, and vibration isolation means to prevent external force such as vibration from outside the system from being transmitted to the system. Say.

In each embodiment, one system is formed by the sensor mechanisms 2a, 2b, 2c and the vibration isolation mechanisms 3a, 3b, 3c.

[First embodiment]
FIG. 1 is a schematic side view showing an AFM holder 100 with a vibration isolation mechanism according to a first embodiment of the invention. As shown in FIG. 1, the AFM holder 100 with anti-vibration mechanism has a sensor mechanism 2a and an anti-vibration mechanism 3a. , a probe 5, a TF-type crystal oscillator 6a as a vibrating piece 6, a detection electrode 7, and a sensor base 8. a pipe 10; In addition, an external holder base portion H is provided below the hollow pipe 10 . As shown in the schematic side view of FIG. 1, they are fixed with an epoxy resin, an adhesive, or the like so as to form layers in sequence. For convenience of explanation, each component in the figures is drawn larger than the actual scale.

The AFM holder 100 with vibration isolating mechanism according to the first embodiment mechanically moves the probe 5 via the TF type crystal oscillator 6a which is the vibrating piece 6 using the exciting piezo 4a which is the vibrating mechanism 4. It is (indirectly) excited.

(Regarding the sensor mechanism 2a)
The sensor mechanism 2a is a mechanism for sensing changes in the vibration of the probe 5 and recognizing the state of the sample surface. In FIG. 1, an excitation piezo 4a, which is a vibration mechanism 4 provided below the probe 5, mechanically excites the probe 5 via a TF-type crystal oscillator 6a, which is a vibrating piece 6. A probe 5 is provided so as to be close to the sample surface S at the free end of the TF crystal oscillator 6a. Next to the vibrating mechanism 4, a sensor base 8 is provided for supporting the TF crystal oscillator 6a.

(About Probe 5)
The probe 5 is formed in the shape of a polygonal pyramid or a cone, and is provided at the free end portion F of the leg 11 of the TF crystal oscillator 6a so that the tip thereof is close to the surface S of the sample. When the probe 5 is brought close to the sample surface S, an attractive force or a repulsive force is generated between the probe 5 and the sample surface S due to Van der Waals force, covalent bond force, and the like. Then, changes occur in the vibration frequency and amplitude of the probe 5, and an AFM image is created from the vibration information.

(Regarding the vibrating bar 6)
In this embodiment, the vibrating bar 6 is a TF (Tuning Fork) type crystal vibrator 6a having two legs 11, and is fixed to the sensor base 8 so as to fall sideways. A probe 5 is provided at the free end F. It has the role of transmitting the vibration propagated from the excitation piezo 4a to the probe 5 and the role of detecting the interaction force acting on the probe 5 and the sample surface S as a frequency shift of the vibrating vibrating bar 6 .

Alternatively, the vibrating piece 6 may be a single tuning fork type crystal oscillator 6b having one leg 11, as shown in FIG. 2(a). The split tuning fork type crystal oscillator 6b has the probe 5 attached to one leg 11 and the other leg 11 is cut off. By replacing the TF type crystal oscillator 6a with the single tuning fork type crystal oscillator 6b as the vibrating piece 6, it is possible to prevent the detection signal from being affected by the vibration from the other leg 11 which is not desired to be detected. can. Also, since there are no extra electrodes, the effects of crosstalk from the excitation voltage can be reduced.

In addition, as shown in FIG. 2B, the vibrating bar 6 may be a semi-electrode crystal vibrator 6c having two bases of the legs 11, but having the electrode circuit C only on one of the legs 11. .

(Regarding the vibration mechanism 4)
In this embodiment, the vibration mechanism 4 is an excitation piezo 4a, which is fixed to the sensor base 8 by a material that can be peeled off with an organic solvent such as epoxy resin or instant adhesive, or by a replaceable method using a screw or spring retainer. It is Vibration of the excitation piezo 4a mechanically excites the probe 5 at the resonance frequency via the sensor base 8 and the vibrating bar 6 .

By mechanically exciting the probe 5 using the excitation piezo 4a, the detection electrode 7 and the excitation electrode are not close to each other. (capacitance current) can be prevented from flowing. Further, by sandwiching the excitation piezo 4a between GND electrodes (not shown) and electrostatically shielding, it is possible to further prevent crosstalk (capacitive current) from flowing. By preventing the flow of crosstalk (capacitive current), no signal noise is generated, and the accuracy of AFM observation can be improved.

In this embodiment, the excitation piezo 4a is stacked in two layers. Since the two-layered structure allows double excitation, the detection signal with respect to the excitation voltage is doubled. Therefore, the two-layer configuration can substantially halve crosstalk. However, if necessary, the number of laminations may be one or three or more, and the number of laminations is not limited.

The excitation piezo 4a is made of lead zirconate titanate (PZT). Alternatively, the excitation piezo 4a may be made of lead titanate, lead metaniobate, bismuth titanate, or crystal, and is not limited as long as it is a piezoelectric element.

(Regarding detection electrode 7)
The detection electrode 7 detects force by utilizing the change in resonance frequency when force acts between the probe 5 and the sample surface when the probe 5 is brought close to the sample surface. The detected signal current is sent to an FM demodulator (not shown) to detect the frequency and estimate the force from the measured frequency shift. An AFM image is obtained by two-dimensionally manipulating the sample surface while feedback-controlling the distance between the probe 5 and the sample surface so that the frequency shift is constant. Also, the detection electrode 7 is connected to an amplifier 13 . Amplifier 13 is either a charge amplifier or a current amplifier.

(Regarding sensor base 8)
The sensor base 8 is adjacent to the excitation piezo 4a, which is the vibration mechanism 4, and is a stand for supporting the TF crystal oscillator 6a that functions as a sensor. Diamond, which has a high specific rigidity, is preferably used for the sensor base 8 . Other materials such as sintered diamond, alumina, ceramics and carbon fiber plastic (CFRP), epoxy glass, quartz plate, etc. are not limited as long as they have high specific rigidity, and can be changed as appropriate according to the application. is.

(Regarding the anti-vibration mechanisms 3a, 3b, 3c)
The vibration isolation mechanisms 3 a , 3 b , 3 c each have a plate member 9 and a hollow pipe 10 . The plate member 9 and the hollow pipe 10 are fixed with an epoxy resin or an adhesive, and are provided between the sensor base 8 and the holder base portion H. As shown in FIG. The vibration isolating mechanisms 3a, 3b, 3c bring the upper sensor mechanisms 2a, 2b, 2c and the holder base portion H closer to a physically separated state in the figure, and reduce the propagation constant of vibration as much as possible. It has a role to make small. Specifically, mainly, the plate member 9 isolates bending vibration, and the hollow pipe 10 isolates parallel vertical vibration.

The vibration isolating mechanisms 3a, 3b, and 3c have a vibration isolating effect of confining the vibration propagated from the sensor mechanisms 2a, 2b, and 2c within the system, and also have a vibration isolating effect below the holder base portion H, which is outside the system (not shown). It has the effect of isolating vibration by suppressing the propagation of changes due to mechanical vibration mode changes and strains generated from the head portion and the like into the system. The vibration isolation mechanisms 3a, 3b, and 3c have effects of vibration isolation and vibration isolation, so that the Q value in the system can be increased. By increasing the Q value, the overall stability of AFM observation can be obtained. For example, it suppresses crashing of the probe 5 due to sudden changes in the vibration mode, suppresses behavior destabilized by a contaminated layer or floating particles on the sample surface S, improves the S/N ratio of AFM observation, Stability can be obtained by reducing individual differences and yields for each holder. In addition, since materials such as rubber that are likely to wear out and deteriorate are not used, there is less time and effort to replace parts, and it can be used for many years even in UHV or extremely low temperature environments.

In addition, an important effect is that there is no influence of a holder attachment/detachment surface (not shown) below the holder base portion H of the vibration isolation mechanisms 3a, 3b, and 3c. In general, the mounting/removing surface of the holder must have a structure with low rigidity, and is easily affected by changes in vibration mode and distortion on the AFM head side. If a very slight change in the contact area of the attachment/detachment surface and the mechanical constant affected by this is propagated to the sensor mechanisms 2a, 2b, and 2c, the frequency shift will fluctuate or be modulated. Then, since AFM observation is performed with frequency shift, it is affected not only by the atomic force but also by mechanical changes on the head side. By using the vibration isolating mechanisms 3a, 3b, and 3c, even if there is a structure with weak rigidity such as the holder attachment/detachment surface, it is possible to realize a state in which they are physically separated, and the effect of this is reflected in the sensor mechanisms 2a, 2b, and 2c. erroneous detection is eliminated.

In addition, regarding the replacement positions of the sensor mechanisms 2a, 2b, and 2c and the holder attachment/detachment surface, practically, the lower part of the sensor base 8 or the lower part of the excitation piezo 4a may be used, and the position is not necessarily limited. not a thing It is important that the presence of the anti-vibration mechanisms 3a, 3b, and 3c separates the influence of the AFM head.

(Regarding plate material 9)
The plate member 9 is a plate with small dimensional change and deformation against bending and twisting forces and high rigidity, and is fixed to the excitation piezo 4a. In the present embodiment, as with the sensor base 8, the plate material 9 is preferably made of diamond, which has a high specific rigidity. Other materials such as sintered diamond, alumina, epoxy glass, ceramics, and carbon fiber plastic (CFRP) are not limited as long as they have a high specific rigidity.

The natural frequency of bending vibration of the plate member 9 in the longitudinal direction of the vibrating bar 6 is different from the frequency of the vibrating vibrating bar 6 . Specifically, the natural frequency of bending vibration of the plate member 9 in the longitudinal direction of the TF-type crystal oscillator 6a differs from that of the vibrating TF-type crystal oscillator 6a by about 10 to 100 times. By making a difference between the natural frequency of the bending vibration of the TF-type crystal oscillator 6a and the natural frequency of the bending vibration of the plate material 9 in the longitudinal direction of the TF-type crystal oscillator 6a, the plate material 9 can be Bending vibration propagated from outside the system is damped and isolated.

It is preferable that the thickness of the plate member 9 is large to suppress bending vibration, but it is preferable that the thickness be such that the center of gravity above the hollow pipe 10 is high and does not sway from side to side during AFM observation.

(About hollow pipe 10)
The hollow pipe 10 is a hollow columnar tube made of stainless steel or the like, and is provided below the layer of the plate member 9 and above the layer of the holder base portion H. As shown in FIG. The hollow pipe 10 is fixed to the plate member 9 and the holder base portion H at one point on the circumference of the hollow pipe 10 in a vertical sectional view with an epoxy resin or an adhesive.

As shown in FIG. 1, the cross-sectional shape of the hollow pipe 10 is hollow circular. Vibrations transmitted from the plate member 9 or the like are first transmitted as longitudinal waves, then converted to transverse waves, propagated along the circumference of the hollow pipe 10, and partially converted to longitudinal waves at the contact points with the holder base H and propagated. , and the rest circulate as transverse waves. In this way, the transformation between transverse and longitudinal waves is repeated over the circumference of the hollow pipe 10 . As a result, parallel vertical vibration transmitted from the plate member 9 or the holder base portion H can be damped and eliminated. Vibrational energy is stored in the hollow pipe 10 instead of absorbing the vibrational energy as heat energy due to internal friction and attenuating the vibration as in the case of using an elastic member whose interior is filled with rubber or the like. Vibrational energy can be mechanically confined within the system without being converted into thermal energy or the like, and as a result, the Q value can be increased.

Further, the hollow pipe 10 is fixed to the plate member 9 so that the axial direction of the hollow pipe 10 is substantially perpendicular to the longitudinal direction of the TF crystal oscillator 6a. The axial direction of the hollow pipe 10 is determined so that the vibration of the sensor mechanism 2a is substantially point-contacted on the generatrix L of the hollow pipe 10 in contact with the plate member 9. As shown in FIG. When the axial direction of the hollow pipe 10 is parallel to the longitudinal direction of the TF crystal oscillator 6a by fixing it so that the axial direction of the hollow pipe 10 is substantially perpendicular to the longitudinal direction of the TF crystal oscillator 6a, That is, compared with the case of line contact in which the vibration of the foot 11 is the same as the axial direction of the hollow pipe 10, the Q value can be increased.

Further, the natural frequency of the bending vibration of the hollow pipe 10 in the circumferential direction is different from the natural frequency of the bending vibration of the plate member 9 in the longitudinal direction of the vibrating bar 6 . Specifically, the natural frequency of the bending vibration of the hollow pipe 10 in the circumferential direction differs from the natural frequency of the bending vibration of the plate member 9 in the longitudinal direction of the TF crystal oscillator 6a by about 10 to 100 times. By making a difference between the natural frequency of the bending vibration of the plate member 9 in the longitudinal direction of the TF type crystal oscillator 6a and the natural frequency of the bending vibration of the hollow pipe 10 adjacent to the plate member 9 in the circumferential direction, the plate member The bending vibration propagated from 9 is further damped and isolated by hollow pipe 10 . It is qualitatively shown that the Q value improves as the natural frequency of bending vibration increases.

Alternatively, the hollow pipe 10 may be a comb-shaped hollow pipe 10a hollowed out in a comb shape, as shown in FIGS. 3(a) and 3(b). The plurality of comb portions 10b are vertically fixed by the shaft portion 10c so as to face in the same direction. It is preferable to arrange the comb portion 10b in a direction perpendicular to the longitudinal direction of the TF crystal oscillator 6a at the contact point between the comb portion 10b and the plate member 9 in order to enhance the effect of vibration isolation.

Also, the number of hollow pipes 10 may be one or more depending on the application as long as structural restrictions allow. Since it is fixed at one point of contact on the circumference, a plurality of hollow pipes 10 can support the plate member 9 stably. Further, if necessary, the cross-sectional shape of the hollow pipe 10 may be oval rather than circular.

[Second embodiment]
FIG. 4 is a schematic perspective view showing an AFM holder 200 with an anti-vibration mechanism according to the second embodiment. The AFM holder 200 with anti-vibration mechanism creates an AFM image by using an optical lever method that detects the frequency shift of the cantilever beam 6d, which is the vibrating piece 6, with a laser beam.

The optical lever method is a method of irradiating a laser beam onto the tip of a cantilever beam 6d provided with a probe 5 and measuring the displacement of the reflected light. When the probe 5 is brought close to the sample surface S, the resonance frequency of the cantilever beam 6d changes due to the physical force such as the atomic force acting between the probe 5 and the sample surface S. AFM observation is performed by controlling the distance between the probe 5 and the sample surface S to be constant by measuring with reflected light.

The AFM holder 200 with a vibration isolation mechanism has a sensor mechanism 2b and a vibration isolation mechanism 3b, as in the first embodiment. 5, an excitation piezo 4a that is a vibration mechanism 4 that excites the probe 5, a cantilever beam 6d that is a vibrating piece 6 provided at the free end F of the probe 5, and a sensor base that supports the cantilever beam 6d. 8 and .

(Regarding the vibration mechanism 4)
Also in this embodiment, the excitation piezo 4a is used as the vibration mechanism 4 to mechanically excite the probe 5 at the resonance frequency via the sensor base 8 and the cantilever beam 6d.

(Regarding the vibrating bar 6)
In this embodiment, the vibrating bar 6 is a cantilever beam 6d. By using the cantilever beam 6d, it is possible to make the spring constant smaller than that of the legs 11 of the crystal oscillators 6a, 6b, and 6c and to make the resonance frequency larger than that of the legs 11 of the crystal oscillators 6a, 6b, and 6c depending on the application. , 6c, and the crystal oscillators 6a, 6b, 6c.

(Regarding sensor base 8)
In this embodiment, the sensor base 8 is preferably made of silica, a semiconductor substrate, or the like.

[Third embodiment]
5, 8, and 9 are schematic side views showing an AFM holder 300 with a vibration isolation mechanism according to a third embodiment of the invention. As shown in FIG. 5, an AFM holder 300 with a vibration isolation mechanism according to the third embodiment has a sensor mechanism 2c and a vibration isolation mechanism 3c. A LER (Length Extension) type crystal resonator 4b, which is a vibration mechanism 4 having a The vibration isolation mechanism 3 c includes a plate member 9 and a hollow pipe 10 . A holder base portion H, which is outside the system, is provided below the AFM holder 300 with vibration isolation mechanism.

In the first and second embodiments, the excitation piezo 4a is used to mechanically excite the probe 5, but in the third embodiment, the probe 5 is electrically (directly) excited. ).

(Regarding the vibration mechanism 4)
As shown in FIG. 5, the vibrating mechanism 4 is a LER crystal oscillator 4b. The vibrating mechanism 4 may be a TF crystal oscillator 4c or a single tuning fork crystal oscillator 4d as shown in FIGS. 8(a) and 8(b) instead of the LER crystal oscillator 4b. In addition, as shown in FIG. 9(a), a shear force crystal oscillator 4e having a base 14 on a vertical TF crystal oscillator and a probe 5 on the base 14 may be used. As shown in FIG. 9B, the vibration mechanism 4 preferably uses a semi-electrode crystal oscillator 4f or a crystal oscillator such as a double-ended tuning fork (DETF) crystal oscillator (not shown). Used. When using the LER type crystal oscillator 4b or the DETF type crystal oscillator, it is vertically placed and fixed to the sensor base 8, and the probe 5 faces upward.

In the case where the vibration mechanism 4 is a shear force type crystal oscillator 4e, it is also fixed vertically with respect to the sensor mechanism 8, and the probe 5 faces upward. 14 may be obliquely attached to the TF type crystal unit in the direction of the depth tilt angle.

Further, the LER crystal oscillator 4b is provided with a detection electrode 7 and an excitation electrode 12. As shown in FIG. By applying a constant voltage to the excitation electrode 12, the minute probe 5 fixed to the free end portion F of the LER crystal resonator 4b is electrically excited at the resonance frequency.

In this embodiment, the AFM measurement method is to create an AFM image with an FM (Frequency Modulation)-AFM measurement system based on a frequency modulation method. The detection electrode 7 detects force by utilizing the change in resonance frequency when force acts between the probe 5 and the sample surface S when the probe 5 is brought close to the sample surface S. FIG. The current of the detection signal is sent to an FM demodulator (not shown) to detect the frequency, and the force is estimated from the measured frequency shift. An AFM image is obtained by two-dimensionally manipulating the sample surface while feedback-controlling the distance between the probe 5 and the sample surface S so that the frequency shift is constant.

In addition to the crystal oscillators 4b, 4c, 4d, 4e, and 4f, the vibration mechanism 4 is a vibrating body made of lead zirconate titanate (PZT), lead titanate, lead metaniobate, bismuth titanate, or the like. It may be a child, and it is not limited as long as it is a piezoelectric element.

Further, the axial direction of the hollow pipe 10 is determined so that the vibration of the foot 11 is substantially point-contacted on the generatrix L of the hollow pipe 10 in contact with the plate member 9 . That is, the hollow pipe 10 is fixed to the plate member 9 so that the axial direction of the hollow pipe 10 is substantially perpendicular to the longitudinal direction of the TF type crystal oscillator 4c when viewed from above.

For example, as shown by thick arrows in FIGS. 6A and 7A, the vibration patterns of the LER crystal oscillator 4b and the TF crystal oscillator 4c are such that the probe 5 is perpendicular to the sample surface S. Or it vibrates to move horizontally. The hollow pipe 10 is fixed to the plate member 9 so as to substantially make point contact on the generatrix L where the hollow pipe 10 contacts the plate member 9 against vibration in this direction. If the direction of the hollow pipe 10 were to be different by 90 degrees, it would substantially be in line contact with the vibration direction at the generatrix L, and the Q value would not increase.

As shown in FIGS. 6(b) and 7(b), the LER type crystal oscillator 4b or the TF type crystal oscillator 4c vibrates vertically or longitudinally on the upper surfaces A of the crystal oscillators 4b and 4c. Therefore, the hollow pipe 10 is fixed to the plate member 9 so that the axial direction of the hollow pipe 10 is substantially perpendicular to the longitudinal direction of the upper surface A, that is, the direction substantially perpendicular to the longitudinal direction of the crystal unit when viewed from above. there is By fixing the plate member 9 in a direction substantially perpendicular to the longitudinal direction of the crystal oscillators 4b and 4c in top view, the effect of vibration isolation and vibration isolation can be enhanced, and the Q value can be increased.

In addition, the natural frequency of the bending vibration of the plate material 9 in the longitudinal direction of the crystal oscillators 4b, 4c, 4d, 4e, and 4f is the same as the frequency of the vibrating crystal oscillators 4b, 4c, 4d, 4e, and 4f. is making a difference. Specifically, the natural frequency of the bending vibration of the plate member 9 in the longitudinal direction of the LER crystal oscillator 4b in top view is different from that of the vibrating LER crystal oscillator 4b by several to 100 times. By making a difference between the natural frequency of the bending vibration of the plate material 9 in the longitudinal direction of the LER type crystal oscillator 4b in the top view and the natural frequency of the vibrating LER type crystal oscillator 4b, the plate material 9 can be Alternatively, bending vibration propagated from outside the system is damped and isolated.

Further, the natural frequency of the bending vibration of the hollow pipe 10 in the circumferential direction is differentiated from the natural frequency of the bending vibration of the plate material 9 in the longitudinal direction of the crystal oscillators 4b, 4c, 4d, 4e, and 4f in top view. ing. Specifically, the natural frequency of the bending vibration of the hollow pipe 10 in the circumferential direction differs from the natural frequency of the bending vibration of the plate member 9 in the longitudinal direction of the LER crystal resonator 4b in the top view by about several to 100 times. . By making a difference between the natural frequency of the bending vibration of the plate member 9 in the longitudinal direction of the LER type crystal oscillator 4b and the natural frequency of the bending vibration of the hollow pipe 10 adjacent to the plate member 9 in the circumferential direction , bending vibration propagated from the plate material 9 is further damped and isolated by the hollow pipe 10 . It is qualitatively shown that the Q value improves as the natural frequency of bending vibration increases.

[Other embodiments]
Moreover, as shown in FIGS. 10(a) and 10(b), the sensor base 8 may be used standing up against the excitation piezo 4a and the plate member 9. FIG.

Further, in the first to third embodiments, the AFM image is created by the FM-AFM measurement system, but in all the embodiments, the AFM image may be created by the AM-AFM measurement system such as AFM in liquid. good.

In addition, in the first to third embodiments, the probe 5 is perpendicular to the sample surface S. The stylus 5 may be brought close, and the measurement environment, measurement method, and the like are not limited as long as the vibration isolation mechanisms 3a, 3b, and 3c are used.

Further, although not shown in the drawings, in the first to third embodiments, the vibration isolating mechanisms 3a, 3b, and 3c have a two-stage structure composed of the plate member 9 and the hollow pipe 10. If so, the plate material 9 and the hollow pipe 10 may be fixed again to the lower part of the hollow pipe 10 to form a four-stage structure. By adopting a four-stage configuration, it may be possible to further enhance the effect of damping bending vibration and parallel up-and-down vibration as compared with the two-stage configuration. Of course, if it is possible on account of the design, it is possible to build up a structure of six or eight stages.

INDUSTRIAL APPLICABILITY The present invention has effects of vibration isolation and vibration isolation, can increase the Q value in the system and enhance the frequency stability, and is applicable to all AFM holders.

100, 200, 300 AFM holder with anti-vibration mechanism 2a, 2b, 2c Sensor mechanism 3a, 3b, 3c Anti-vibration mechanism 4 Vibration mechanism 4a Excitation piezo 4b LER crystal oscillator 4c TF crystal oscillator 4d Half Tuning-fork crystal oscillator 4e Shear-force crystal oscillator 4f Semi-electrode crystal oscillator 5 Probe 6 Vibrating piece 6a TF-type crystal oscillator 6b Single-split tuning-fork crystal oscillator 6c Half-electrode crystal oscillator 6d Cantilever beam 7 Detection electrode 8 Sensor base 9 Plate material 10 Hollow pipe 10a Comb-shaped hollow pipe 10b Comb portion 10c Shaft portion 11 Foot 11a Foot 12 Electrode for excitation 13 Amplifier 14 Base S Sample surface F Free end C Electrode circuit H Holder base L Bus bar A top surface

Claims (6)

having a sensor mechanism and an anti-vibration mechanism,
The sensor mechanism includes a probe brought close to the surface of the sample,
a vibration mechanism that excites the probe,
The anti-vibration mechanism includes a plate member fixed on the front side so as to be adjacent to the sensor mechanism;
and a cylindrical hollow pipe fixed at one point on the circumference in a vertical cross-sectional view on the back side of the plate material. The sensor mechanism comprises a vibrating piece having a free end provided with the probe,
2. The vibration isolating mechanism according to claim 1, wherein the hollow pipe is fixed to the plate material with the axial direction of the hollow pipe being substantially perpendicular to the longitudinal direction of the vibrating bars. AFM holder with. The vibration mechanism is a crystal oscillator,
2. The vibration isolator according to claim 1, wherein the hollow pipe is fixed to the plate member such that the axial direction of the hollow pipe is substantially perpendicular to the longitudinal direction of the crystal unit when viewed from above. AFM holder with anti-vibration mechanism. A natural frequency of the bending vibration of the plate material in the longitudinal direction of the vibrating piece or a natural frequency of the bending vibration of the plate material in the longitudinal direction of the crystal oscillator in a top view and a natural frequency of the bending vibration of the hollow pipe in the circumferential direction 4. The AFM holder with vibration isolation mechanism according to claim 2 or 3, wherein the vibration frequencies are different from each other. 5. The AFM holder with anti-vibration mechanism according to claim 1, wherein the plate material contains diamond. 6. The AFM holder with anti-vibration mechanism according to any one of claims 1 to 5, wherein said sensor mechanism comprises a sensor base containing diamond adjacent to said vibration mechanism. .

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