JPH1196607A - Probe and information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a compact probe and whose energy consumption is little, by minutely rotating a cantilever around the shaft in the longitudinal direction and horizontally moving the tip of a probe at the position separated from the rotary shaft of the cantilever. SOLUTION: A positive voltage is applied to an upper electrode 107b with respect to a lower electrode 105b and a negative voltage is applied to an upper electrode 107a with respect to the lower electrode 105a 5. Since a piezo-electric member 106 is extended but lengths of L-shaped members 104a, 104b do not change, the L-shaped 104b, the upper and lower electrode 105b, 107b and the piezo-electric member 106 are projectingly deformed upward. Then, a moment rotating rightward acts on a cantilever 102 by these movements and the tip of a probe 101 is moved rightward. When voltages to be applied on the electrodes are made to be reverse direction, the tip of the probe 101 is moved leftward. Voltages to be applied on the upper electrodes 107a, 107b and the lower electrodes 105a, 105b are controlled in this manner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe and an information processing apparatus, and more particularly, to a scanning probe microscope (such as a scanning tunneling microscope (hereinafter abbreviated as STM) and an atomic force microscope (hereinafter abbreviated as AFM)). The present invention relates to a probe in the technical field of a high-density and large-capacity memory device using the principle of SPM) and an information processing device.

[0002]

2. Description of the Related Art A scanning tunneling microscope (STM) capable of directly observing the electronic structure of surface atoms of a semiconductor has been developed by G. Binich et al. (Fervetica Physica Actor.5).
5, 726 (1982)), scanning probe microscope (SPM) that obtains various kinds of information by scanning with a sharp-pointed probe, and furthermore, to apply electrical, chemical or physical action to a substrate. Research and development of fine processing technology applying SPM for the purpose of Further, such SPM technology is being applied to memory technology. For example, JP-A-63-161552 and JP-A-63-161553 describe materials having a memory effect on the switching characteristics of voltage and current as a recording layer.
For example, a method is disclosed in which recording / reproduction is performed by STM using a thin film layer of a π-electron organic compound or a chalcogen compound as a recording medium. According to this method, by applying a voltage equal to or higher than a certain threshold value to the STM probe, recording is performed by causing a change in characteristics in a very small area on the recording medium immediately below the probe. Reproduction can be performed using the fact that the tunnel current flowing between the recording portion and the non-recording portion changes. If the recording bit size is set to 10 nm in diameter using this method, an information processing device having a recording density of 10 ¹² bits / cm ² can be realized. In addition, when a voltage higher than a certain threshold value is applied as a recording medium, a material whose surface locally melts or evaporates to change its surface shape into a concave or convex shape, for example, by using a metal thin film such as Au or Pt, is used. Can be recorded and reproduced.

In order to read a large amount of information using the above-described recording / reproducing method, it is necessary to detect the position of the probe in the X and Y directions (in-plane of the recording medium) and perform correction control (tracking). . As a tracking method for an SPM memory device, a method is first known in which a physical track is formed on a medium and a probe is made to follow the track. Japanese Patent Application Laid-Open No. 1-107341 discloses a method in which a V-shaped groove is formed as a track on the surface of a recording medium and the probe electrode is always positioned at the center of the groove. JP-A-1-133239 discloses a method in which a track is formed by a conductive band layer under a recording medium, a tracking signal is applied to the track, and feedback control is performed based on the tracking signal detected from a probe. Have been. However, it is not easy to create a physical track having a track width of about 10 nm in order to exhibit the advantages of the SPM technology by using a conventional photolithography technology or the like. Therefore, as a method of tracking an information sequence without forming a special track on a medium, Japanese Patent Application Laid-Open No. 4-212737 discloses a method in which the position of a recording bit is determined while vibrating a probe in a direction perpendicular to the bit sequence with a small amplitude. A tracking method (wobbling method) for detecting and controlling so as to eliminate the displacement is disclosed.

Hereinafter, this wobbling method will be described. First, in the wobbling method, when a recorded information bit string is scanned by a probe to extract a reproduction signal, the probe is steadily vibrated at a wobbling frequency f in a direction orthogonal to the bit string with an amplitude smaller than the width of the bit string. Keep it. Here, the wobbling frequency f is set to a value sufficiently smaller than the frequency of the reproduced signal of the bit string. Then, the signal is reproduced by scanning the bit string with a probe. At this time, the intensity of the reproduction signal changes according to the positional relationship between the probe and the bit string, as shown in FIG. That is, as shown in the graph of FIG. 5, the amplitude intensity of the reproduced signal becomes maximum when the probe is directly above the bit sequence, and decreases when the probe departs from the bit sequence. At this time, since the probe vibrates minutely at the frequency f as shown in FIG. 6A, the reproduced signal of the bit string is represented by the signal b and the signal b in FIG. The envelope changes like c and d.

[0005] Here, when the change signal of the envelope of the reproduction signal is extracted, it becomes like signals b ', c', and d 'in FIG. First, with respect to the vibration waveform a of the probe, the envelope change signal becomes smaller like the signal c ′ when the probe is directly above the bit string as shown by the arrow c, and has a frequency twice the wobbling frequency f. 2f appears. Therefore, when synchronous detection is performed using the reference signal having the frequency f of the probe as a reference signal, the value becomes zero, and the error voltage becomes zero. Synchronous detection is performed by, for example, a multiplier and a filter. Further, when the probe is shifted upward as indicated by an arrow b, the phase is shifted by 180 degrees with respect to the vibration waveform a of the probe and the amplitude is increased. , And the amplitude also increases. Therefore, when synchronous detection is performed using the reference signal of the frequency f of the probe as a reference signal, tracking is proportional to the amount of displacement from the bit string, such that the probe becomes negative when the probe moves upward and positive when the probe moves downward. A signal is obtained. Using this signal, it is possible to perform feedback control such that the probe is kept on the bit string. For stable tracking, the wobbling frequency f needs to be about two orders of magnitude higher than the required tracking frequency. In general, the required tracking frequency is proportional to the probe scanning speed.

[0006]

However, conventionally, in order to perform wobbling, a probe or a recording medium is driven in a horizontal direction using an actuator. Therefore, the mass to be driven becomes large, and the frequency f of wobbling cannot be sufficiently increased. This has been a factor limiting the data transfer speed of the memory device. In addition, since an actuator device for driving in the horizontal direction becomes large-sized, in the case of an SPM memory provided with a plurality of probes, it is impossible to individually perform wobbling with each probe. Further, the energy consumption for wobbling increases, which hinders a reduction in power consumption of the memory device.

Therefore, the present invention solves the above-mentioned problems in the prior art, enables wobbling at a high frequency, and has a compact SP having a plurality of probes.
It is an object of the present invention to provide a probe which is suitable for M memory and consumes less energy, and to provide an information processing apparatus including the probe and capable of reading information at high speed.

[0008]

To solve the above-mentioned problems, the present invention is characterized in that a probe and an information processing apparatus are configured as follows. That is, the probe of the present invention is a probe provided with a probe at a free end of a cantilever whose one end is supported, in which the cantilever is slightly rotated about its longitudinal axis, and the minute rotation causes the cantilever to rotate from the rotation axis of the cantilever. It is characterized by having driving means for horizontally moving the tip of the probe at a distant position. Further, the drive means of the probe of the present invention is configured to be driven so that a drive frequency of the drive means is matched with a frequency of a mode in which the cantilever vibrates so as to be twisted among vibration modes of the cantilever. It is characterized by. In the probe according to the present invention, the driving unit is a piezoelectric actuator. Also, in the probe of the present invention, the piezoelectric actuator is disposed on a connecting member connected to the support portion of the cantilever on the left and right of the cantilever, and is polarized so that the connecting member on the left and right is bent by application of a voltage. And a piezoelectric member. In the probe according to the present invention, the driving unit is an electrostatic actuator. Further, in the probe of the present invention, the electrostatic actuator includes a movable electrode disposed on the left and right sides of the cantilever, and a fixed electrode opposed to the movable electrode. It is characterized by being configured to exert an attractive force.
Further, an information processing apparatus according to the present invention is an information processing apparatus to which the principle of a scanning probe microscope is applied, including any one of the above-described probes according to the present invention, and performing wobbling by horizontal movement of a probe tip by minute rotation of a cantilever. And the recorded information is reproduced.

[0009]

According to the present invention, a wobbling can be performed at a high frequency by the above-mentioned configuration, and a probe suitable for a compact SPM memory having a plurality of probes and consuming less energy can be realized. it can.
In addition, by configuring an information processing device including the probe, an information processing device that can read information at high speed can be provided.

Next, the operation of the probe having the above configuration will be described.
Will be described. Figure 3 shows a cantilever with a probe at the tip
FIG. 4 is a perspective view of the bar, and FIG.
You. In each figure, 901 is a probe, 902 is a cantilever, 9
03 is a support part. In FIG. 3, L, w, and t are
The length, width, and thickness of the anti-lever are shown. Figure 4
Where h is the distance between the tip of the probe and the center of rotation of the cantilever.
Separation and θ indicate the rotation angle of the cantilever. Of the present invention
FIG. 2 is a schematic view of the probe as viewed along a longitudinal axis. Figure
As shown in Fig. 4, the tip of the cantilever is rotated by an angle θ.
I do. At this time, if the angle θ is small,
The end moves hθ horizontally in the figure. That is, cantilever
When the tip is rotated in the range of -θ to + θ, the tip of the probe
Can be wobbled with a width of 2hθ. here
And the effective mass m, which is a measure of ease of driving_eabout
Think. Where the effective mass m_eIs the force F applied to the tip of the probe
When added, acceleration  Occurs,Is defined by m_eCan be accelerated with less force as is smaller
Indicates that For simplicity, ignore the tip mass and
The chiller has a simple rectangular shape (length L,
It is assumed that the width is w and the thickness is t) and the density is ρ. First, can
Effective mass m when driving the entire chiller in parallel_e1Is
Because it is equal to the mass of the whole cantilever,It is.

Next, consider the effective mass _me2 seen from the tip of the probe when the cantilever is driven to rotate minutely. As shown in FIG. 4, when the tip of the probe is displaced by hθ, a force F is applied to the tip of the probe.
Is acting. The moment of inertia I when the cantilever rotates around the rotation axis is It is. In general, the product of angular acceleration and moment of inertia is equal to torque, so And the small effective mass _me2 seen from the tip of the probe is That is, If h is determined so that the following equation is obtained, it can be seen that the effective mass of the wobbling method of the present invention is smaller than that of the parallel movement. For example, as typical values, t = 1 μm, w = 20
In the case of μm, by setting h> 5.8 μm, the effective mass can be made smaller than when the cantilever is translated.

Furthermore, in the method of moving the cantilever in parallel, it is necessary to simultaneously drive the support, so it is necessary to add the mass of the support to the effective mass. In the present invention, however, it is not necessary to move the support. This is further advantageous in reducing the effective mass. That is, according to the present invention, it is possible to provide a probe that can easily perform high-speed wobbling by rotating and driving the cantilever as compared with the conventional method of driving the entire probe in parallel left and right.

Further, by driving the driving means so that the driving frequency of the driving means coincides with the frequency of a mode in which the cantilever vibrates so as to be twisted among the vibration modes of the cantilever, energy consumption required for wobbling is reduced. Can be. Further, by using a piezoelectric actuator as the driving means, it is possible to provide a compact probe suitable for an SPM memory device having a plurality of probes. Further, even when the driving means is an electrostatic actuator, a compact probe suitable for an SPM memory device having a plurality of probes can be provided. Further, by applying the probe of the present invention to an information processing device to which the principle of a scanning probe microscope is applied, an information processing device capable of reading information at high speed can be provided.

[0014]

Embodiments of the present invention will be described below. Embodiment 1 FIG. 1 is a perspective view of a probe according to Embodiment 1 of the present invention. The cantilever 102 has a probe 10 at its tip.
1 is arranged, and the other end is fixed to the support portion 103.
The probe 101 is conductive and is electrically connected to the probe lead electrode 110. Further, the vicinity of the fixed end of the cantilever 102 is connected to the support portion 103 by L-shaped members 104a and 104b. Then, the L-shaped member 104
a, b, the lower electrodes 105a, b, the piezoelectric member 1
06a and b and the upper electrodes 107a and 107b are stacked. The lower electrodes 105a, b and the upper electrodes 107a, b are electrically connected to the upper electrode lead electrodes 108a, b and the lower electrode lead electrodes 109a, b, respectively.
The piezoelectric members 106a and 106b are connected to the upper electrodes 107a,
When a positive voltage is applied to the lower electrodes a and b, a polarization process is performed so that the electrode b expands in the longitudinal direction and contracts in the longitudinal direction when a negative voltage is applied.

Next, the operation of the present probe will be described. FIG. 2 is a view of the probe of the present invention as viewed from the length direction of the cantilever 102, and illustrates the operation of the present probe. FIGS. 2A, 2B, and 2C show that the probe is at the neutral position, right side, and left side, respectively.
In the state of FIG. 2A, no voltage is applied to each electrode. In FIG. 2B, a positive voltage is applied to the upper electrode 107b with respect to the lower electrode 105b, and a negative voltage is applied to the upper electrode 107a with respect to the lower electrode 105a. At this time, the piezoelectric member 106a contracts, and the piezoelectric member 106b expands. At this time, since the lengths of the L-shaped members 104a and 104b do not change, the members 104b to 107b are deformed upwardly convex in the drawing, and the members 104a to 107a are deformed downwardly convex in the drawing. I do. By these movements, a moment for rotating the cantilever 102 rightward in the figure acts, and the tip of the probe 101 moves rightward in the figure.
Conversely, in FIG. 2C, the voltage applied to the electrodes is in the opposite direction, so that the probe moves to the left, contrary to FIG. 2B. Thus, the probe of the present embodiment also has the upper electrodes 107a, 107b and the lower electrode 1 similarly to the first embodiment.
It can be seen that the tip of the probe can be wobbled to the left and right by controlling the voltage applied to 05a and 05b.

FIG. 8 is a perspective view of a probe according to a second embodiment of the present invention. In the cantilever 302, a probe 301 is disposed at a tip portion, and the other end is fixed to a support portion 303. The probe 301 is conductive and is electrically connected to the probe lead electrode 310. Further, bar members 304a and 304b are arranged near the fixed end of the cantilever 302. The movable electrodes 305a and 305b are disposed on the rod members 304a and 304b, respectively.
a and b are electrically connected to the movable electrode extraction electrodes 309a and 309b. And the movable electrodes 305a, 305b
The fixed electrodes 307 are respectively formed through the gaps 306a and 306b.
a and b. The fixed electrodes 307a and 307b are fixed at one end to the support portion 303,
8a and 8b.

Next, the operation of the present probe will be described. First, the movable electrode extraction electrode 308a and the fixed electrode 3
When a voltage is applied during the period 07a, an electrostatic attractive force acts between the movable electrode 305a and the fixed electrode 307a. Then, a force acts upward on the rod-shaped member 304a in the figure, and the cantilever 3
02 acts to the left. Then
The tip of the probe 301 moves to the left in the figure. Similarly, by applying a voltage between the movable electrode extraction electrode 308b and the fixed electrode 307b, the tip of the probe 301 can be moved to the right in the drawing. As described above, by applying a drive voltage, the probe can be used in exactly the same way as the probe of the first embodiment. Further, the probe of the present embodiment is different from the probe of the first embodiment,
Since no piezoelectric element is required, there is an advantage that the manufacturing process is easy.

[Embodiment 3] An outline of a recording / reproducing apparatus of Embodiment 3 will be described with reference to FIG. In the present embodiment, a recording medium 2 including a recording layer 202 on a conductive substrate 201 is used.
The probe 207 is arranged so that the probe 204 provided at the tip thereof comes into contact with 03. The probe 207 is the same as that described in the first and second embodiments. In the probe 207, the probe 204 is supported by a cantilever 205 that elastically deforms to bend, and a small-angle rotary actuator 206 is arranged near the fixed end of the cantilever 205. here,
The elastic constant of the elastic deformation of the cantilever 205 viewed from the tip of the probe 204 is about 0.1 [N / m], and the elastic deformation amount is about 1
[Μm], the contact force of the probe with the recording medium is about 10 ⁻⁷ [N]. Control computer 23
4 receives a position control signal from the position control circuit 233 controlled by the
The xyz stage 209 on which the probe 03 is mounted is driven, and the probe 207 and the recording medium 203 relatively move in the three-dimensional direction. For recording and reproduction, the recording medium 2
The position of the probe 207 is adjusted relative to the position of the probe 207 so that the tip of the probe 204 is in a desired position on the recording medium 203 and is brought into contact with a desired contact force. Is done.

In the recording / reproducing apparatus described above, the recording medium 20
When scanning the probe 207 with respect to the
The tip of the upper probe 204 always keeps in contact with the recording medium 203. Such a contact scanning method uses the probe 20
(4) When scanning is performed while the leading end is in contact with the recording medium 203, even if the surface of the recording medium 203 has irregularities, it is absorbed by the elastic deformation of the cantilever 205.
The contact force between the tip of the probe 204 and the surface of the recording medium 203 is kept substantially constant, so that the tip of the probe 204 and the surface of the recording medium 203 can be prevented from being broken. This method does not require a means for controlling the probe in the z direction, so that the configuration is not complicated, and is particularly suitable for an apparatus having a plurality of probes. Also, z of each probe 207 with respect to the recording medium 203
Since the feedback control of the directional position is unnecessary, the probe 206 can scan the recording medium 203 at high speed.

When recording information, the tip of the probe 204 is kept in contact with the recording medium 203,
While scanning, a recording signal generated by the recording control circuit 223 controlled by the control computer 234 is applied from the probe 204 to the recording medium 203 through the changeover switch 221 switched to the recording system. In this way, recording is locally performed on the portion of the recording layer 202 where the tip of the probe 204 contacts. For the recording layer 201 in the above-described apparatus, a material whose current value changes by voltage application is used. As a specific example, the first
JP-A-63-161552 and JP-A-63-1
LB film (= Langm) having an electric memory effect such as polyimide or SOAZ (bis-n-octylsquarylium azulene) as disclosed in US Pat.
(a cumulative film of organic monomolecular films formed by the uir-Blodgette method). This material is
Voltage (5 to 10 [V]) equal to or higher than the threshold value between the LB film and the substrate
(Approximately), the conductivity of the LB film changes (OFF
State → ON state), and the bias voltage for reproduction (0.01
The current flowing when about 2 [V] is applied increases.

As a second specific example, GeTe, GaS
b, an amorphous thin film material such as SnTe. This material applies a voltage between the probe, the amorphous thin film material, and the substrate,
The heat generated by the flowing current causes a phase transition from amorphous to crystalline. As a result, the conductivity of the material changes, and the current flowing when a bias voltage for reproduction is applied increases. As a third specific example, an oxidizable metal / semiconductor material such as Zn, W, Si, and GaAs can be given. When a voltage is applied between the probe and the oxidizable metal / semiconductor material, the material reacts with water adsorbed on the surface of the material or oxygen in the atmosphere due to a flowing current to form an oxide film on the surface. For this reason, the contact resistance of the material surface changes, and the current flowing when the bias voltage is applied decreases.

The reproduction of the information recorded as described above is performed as follows. First, in the probe 207, the wobbling drive circuit 231 controlled by the reference signal oscillator 230 controls
06 is driven, and the tip of the probe 204 is wobbled with a width sufficiently smaller than the bit width. Changeover switch 2
21, the signal wiring from the probe 207 is switched to the reproducing system, and then a bias voltage is applied between the probe 204 and the substrate 201 by the bias voltage applying means 222.
The current flowing therebetween is converted into a voltage in the current-voltage conversion circuit 225. Since a larger amount (or less) of current flows in the portion of the recording bit on the recording medium 203 than in the portion where no recording is performed, the presence or absence of the bit is converted into a voltage signal. Then, the reproduced signal is transmitted to the band-pass filter 227.
Through the demodulation circuit 226 to the control computer 234 as binary data.

On the other hand, the output of the band pass filter 227 is also input to the synchronous detection circuit 228. The synchronous detection circuit 228 performs synchronous detection on the output of the band-pass filter 227 and the output of the reference signal oscillator 230 through the signal that has passed through the waveform shaping circuit 229 to generate an error signal. This error signal is a signal proportional to the displacement between the probe 204 and the bit string. The error signal is input to the position control circuit 233 through the low-pass filter 232, and the position control circuit 233
In conjunction with the control output from No. 4, position control is performed so as to reduce the tracking error. Thus, the information recorded on the recording medium 203 can be reproduced.

Next, the wobbling frequency of the present embodiment will be described. The tracking error of the SPM memory device described above needs to be suppressed to about 1 nm when the size of one bit is 10 nm. SP of this embodiment
The specifications of the M memory are scanning method: raster scanning, horizontal scanning width: 100 μm, 1-bit length: 20 nm, and transfer rate: 1 Mbps. Possible causes of the tracking error of the SPM memory performing the raster scanning as in the present embodiment are temperature drift and non-parallelism between the bit string and the driving direction. Here, since the temperature drift causes a DC tracking error, only the tracking error caused by the non-parallelism between the bit string and the driving direction will be considered. In this embodiment, since the 1-bit length is 20 nm, the scanning speed of the probe is 20 mm / s in order to realize a transfer rate of 1 Mbps.

Here, assuming that raster scanning with a horizontal scanning width of 100 μm is performed, the horizontal scanning frequency is 20 mm / s.
/ 200 μm = 100 Hz. The tracking error caused by the arrangement of the bit strings is a multiple component of the fundamental frequency. Such a tracking error is generally 1 /
It is known that it decreases in proportion to f ² . Assuming that the amplitude of the track deviation is 1 μm at the maximum, the control gain is 60 to suppress the tracking error within 1 nm.
dB is required. If the amplitude of the tracking error at 100 Hz is 1 μm at the maximum, the frequency becomes
If the magnification becomes 0, the tracking error becomes 1 nm or less. Therefore, it is sufficient for the servo to follow up to about 100 × {1000} 3 kHz.

From this, it can be seen that the required wobbling frequency f should be within the range of 3 kHz <f <1 MHz. Therefore, in this embodiment, f = 100 kHz. By setting the frequency of the torsional vibration mode of the cantilever 102 to 100 kHz, wobbling could be performed with low power consumption. As mentioned above,
By applying the probe of the present invention to the SPM recording / reproducing apparatus, it becomes possible to perform wobbling at a higher speed than in the past, thereby enabling high-speed data reading.

[0027]

As described above, according to the present invention, the whole probe is horizontally moved left and right by slightly rotating the cantilever around its longitudinal axis and horizontally moving the tip of the probe in the cantilever. As compared with the probe, it is possible to easily wobble the probe at high speed. Further, in the present invention, the driving frequency of the driving means for micro-rotating the cantilever,
By driving the cantilever in accordance with the frequency of the mode in which the cantilever vibrates in a twisting manner, the energy consumption required for wobbling can be extremely reduced.
Further, in the present invention, the driving means is constituted by a piezoelectric actuator or an electrostatic actuator, so that the SPM having a plurality of compact probes is provided.
A probe suitable for a memory device can be realized.
Further, according to the present invention, an information processing device capable of reading information at high speed can be provided by configuring the information processing device with the above-described probe of the present invention.

[Brief description of the drawings]

FIG. 1 is a perspective view of a probe according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating the operation of the probe according to the first embodiment of the present invention.

FIG. 3 is a schematic view of a probe of the present invention.

FIG. 4 is a front view of the probe of FIG. 3;

FIG. 5 is a diagram illustrating a scanning state in the wobbling tracking method.

FIG. 6 is a diagram illustrating a state of a reproduced signal in the wobbling tracking method.

FIG. 7 is a block diagram of an information processing apparatus according to a third embodiment of the present invention.

FIG. 8 is a perspective view of a probe according to a second embodiment of the present invention.

[Explanation of symbols]

 101, 301, 901: Probe 102, 302, 902: Cantilever 103, 303: Support 104a, b: L-shaped member 105a, b: Lower electrode 106a, b: Piezoelectric member 107a, b: Upper electrode 108a , B: upper electrode lead electrode 109a, b: lower electrode lead electrode 110, 310: probe lead electrode 309a, b: movable electrode lead electrode 304a, b: rod-shaped member 305a, b: movable electrode 306a, b: void 307a, b: fixed electrode 308a, b: fixed electrode lead-out electrode 201: substrate 202: recording layer 203: recording medium 204: probe 205: cantilever 206: small angle rotary actuator 207: probe 208: xyz drive mechanism 209: xyz stage 221: Changeover switch 222: bias applying means 23: Recording control circuit 224: Reproduction control circuit 225: Current-voltage conversion circuit 226: Demodulation circuit 227: Band pass filter 228: Synchronous detection circuit 229: Waveform shaping circuit 230: Reference signal oscillator 231: Wobbling drive circuit 232: Low pass filter 233 ： Position control circuit 234 ： Control computer

Claims (7)

[Claims] 1. A probe provided with a probe at a free end of a cantilever supported at one end, wherein the cantilever is slightly rotated around its longitudinal axis, and the micro-rotation separates the cantilever from a rotation axis of the cantilever. A driving means for horizontally moving the tip of the probe. 2. The driving device according to claim 1, wherein the driving device is configured to drive the driving frequency of the driving device in accordance with a frequency of a mode in which the cantilever vibrates so as to be twisted among vibration modes of the cantilever. The probe according to claim 1, wherein 3. The probe according to claim 1, wherein said driving means is a piezoelectric actuator. 4. The piezoelectric actuator according to claim 1, wherein the piezoelectric actuator is disposed on a connecting member connected to a support portion of the cantilever on the left and right sides of the cantilever, and the piezoelectric actuator is polarized so as to bend the connecting member on the left and right by applying a voltage. The probe according to claim 3, wherein the probe is constituted by a member. 5. The probe according to claim 1, wherein said driving means is an electrostatic actuator. 6. The electrostatic actuator comprises a movable electrode disposed on the left and right of the cantilever and a fixed electrode opposed to the movable electrode, and applies an electrostatic attraction between the left and right electrodes by applying a voltage. The probe according to claim 5, wherein the probe is configured as follows. 7. An information processing apparatus to which the principle of a scanning probe microscope is applied.
The wobbling is performed by horizontal movement of the tip of the probe due to micro rotation of the cantilever,
An information processing apparatus for reproducing recorded information.