JP2002243618A - Method for measuring illumination reflection mode in scanning near-field microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a measuring method with satisfactory efficiency in collecting light in illumination reflection mode in a scanning near-field microscope. SOLUTION: While a probe is shaken in the vertical directions with respect to a sample, light incident onto the probe is modulated. The light is irradiated from the tip of the probe at a location, at which the tip of the probe is farther from the sample than it is closest to the sample and is reflected light from the sample at the time is locked in and detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an illumination reflection mode in a scanning near-field microscope for measuring optical characteristics of a sample surface by irradiating a sample with evanescent light from a probe and measuring the reflected light intensity at that time. The method relates to a method for measuring.

[0002]

2. Description of the Related Art Several types of scanning near-field microscopes have been developed. Among them, in the scanning near-field microscope of the method called the illumination mode, the tip is sharpened, light is incident on a probe having a minute aperture, evanescent light is generated near the minute aperture, and the distance between the sample and the tip of the probe is reduced. , Evanescent existence area (generally
(100 nm or less), scan the sample and probe relatively while keeping the distance between them, and collect the light scattered on the sample surface at that time. By measuring the strength,
Measurement of the optical properties of the sample surface is performed. At this time, it is possible to perform optical measurement with a resolution exceeding the diffraction limit. The region where the evanescent light exists is limited to the very vicinity of the minute aperture, and the intensity decreases exponentially with the distance from the opening. Therefore, in order to use the evanescent light as illumination for the sample, it is necessary to make the distance between the sample and the probe tip close to the region where the evanescent light exists. When the sample approaches the region where the evanescent light exists, the evanescent light is scattered on the sample surface, and the scattered light acts as propagating light, and can be handled in the same manner as ordinary light.

In controlling the distance between the sample and the probe tip in a scanning near-field microscope, the probe tip is moved close to the sample while vibrating in the vertical direction near the resonance frequency of the probe, and the probe tip is moved to the probe tip. A method is used in which a fine movement mechanism controls the amplitude or phase change due to the atomic force acting on the sample surface or the probe amplitude or phase change due to intermittent contact of the sample. ing.
This method is called a vibration type AFM control method. In this scheme,
The tip of the optical fiber is sharpened, bent in the long axis direction of the probe, and a bent type probe with a small opening of approximately 200 nm or less at the tip and a sharpened probe at the tip of the cantilever are formed. A microcantilever or the like having an opening at the tip of the probe and having an optical waveguide for introducing light into the opening is mainly used. In addition, for detecting the amplitude of the probe, an optical detection means such as an optical lever method or a piezoelectric body is brought into contact with the probe, and the amplitude is detected by a change in the amount of electric charge generated from the piezoelectric body due to a change in the amplitude of the probe. A method is used. Further, a piezoelectric element or a voice coil motor is used for the fine movement mechanism.

Further, the probe tip is brought close to the sample while being vibrated in the horizontal direction with respect to the sample surface, and the amount of change in the amplitude or phase of the probe due to the shear force acting on the probe tip and the sample surface becomes constant. As described above, a method of controlling by a fine movement mechanism is also used. This method is called a shear force control method. In this method, a straight type probe in which the tip of an optical fiber is sharpened and a minute opening is provided at the tip is mainly used.

In these illumination-type scanning near-field microscopes, a mode for condensing light transmitted through the sample after evanescent light is scattered by the sample is a mode for condensing light transmitted therethrough, and a mode for condensing reflected light. Is called an illumination reflection mode. The illumination transmission mode is used for a transparent sample such as a living body or an organic thin film. On the other hand, the illumination reflection mode is used for observing non-transmissive samples such as semiconductors and metal thin films.

In a scanning near-field microscope using an illumination mode, incident light is optically modulated in synchronization with a probe oscillation cycle in order to improve resolution and S / N ratio.
Japanese Patent Application Laid-Open No. Hei 7-260808 discloses a method in which the phase or the intermittent rate in the light modulating means is changed to change the emission timing and emission time from the opening.

In a scanning near-field optical microscope, the resolution decreases as the distance between the probe and the sample increases. When performing the vibration type AFM method in the method of JP-A-7-260808, the phase and the intermittent rate are changed by applying modulation according to the amplitude of the probe to the evanescent light, and only when the probe and the sample are closest to each other. By emitting light,
It is possible to remove an optical signal component in a case where the distance between the sample and the probe, which causes a decrease in resolution, is increased, and as a result, the resolution can be improved.

In the shear force method, the resolution decreases as the distance from the center of vibration increases.
By emitting light only in the vicinity of the center of vibration according to the method disclosed in the publication, signal components that cause a reduction in resolution can be removed, and the resolution is improved.

Also, optical signals handled by a scanning near-field microscope are generally very weak, and tend to have a poor S / N ratio. In the method disclosed in Japanese Patent Laid-Open No. Hei 7-260808, it is possible to improve the S / N ratio by performing lock-in detection on a modulated optical signal.

Further, in a scanning near-field microscope using a shear force control method, the tip of the probe is caused to elliptically oscillate with respect to the sample surface, and in addition to controlling the distance by changing the amplitude in the horizontal direction, the light is modulated by the vibration in the vertical direction. Do
A measurement method to improve the S / N ratio by lock-in detection of a signal is described by Ishikawa et al. In Optics Japan'99 Preprints 24aB1 pp.233-234.

[0011]

SUMMARY OF THE INVENTION
When the method of JP-A-7-260808 is used in the illumination reflection mode, there are the following problems.

In the illumination transmission mode, the objective lens for focusing is arranged on the side opposite to the probe with respect to the sample, so that the solid angle of the objective lens can be used effectively. However, in the case of the illumination reflection mode, it is necessary to arrange the focusing objective lens on the same side of the sample as the probe. In this case, it is difficult to dispose the objective lens so that the solid angle of the objective lens can be used most effectively because the probe is in the way. Make an objective lens that avoids the portion of the axis passing through the probe tip from a strong sample, or
There is a need to combine a concave mirror for focusing and collect the signal while avoiding the part where the probe is arranged.However, both methods have significantly lower focusing efficiency than the illumination transmission mode. .

Further, when light is irradiated at a place where the sample and the tip of the probe are closest to each other with the aim of improving the resolution, the probe blocks light scattered from the sample, and it is extremely difficult to detect a signal. .

In the method of Ishikawa et al., After irradiating evanescent light from a probe in an illumination mode, light scattered by a sample is condensed from the same aperture of the probe as in the irradiation, and lock-in detection is performed. It is a method to perform. Such a method is called an illumination collection mode, and has a different detection form from the illumination reflection mode. In the case of the illumination collection mode, the aperture of the probe is very small, so that the light collection efficiency is low, and the loss of the coupling portion of the optical fiber for transmitting the light cannot be ignored.

Therefore, when a non-transmissive sample is measured by a scanning near-field microscope, the illumination collection mode and the illumination reflection mode are selectively used depending on the purpose of measurement, but the method of Ishikawa et al. Has a problem in the illumination reflection mode. It is impossible to do point resolution.

Accordingly, an object of the present invention is to solve the above-mentioned conventional problems by obtaining a measuring method with a high light-collecting efficiency in an illumination reflection mode in a scanning near-field microscope.

[0017]

In order to solve the above-mentioned problems, according to the present invention, a probe having a sharpened tip, a minute opening at the tip, and a bent tip in the longitudinal direction of the probe is provided. And a vibrating means for vertically vibrating the probe tip with respect to the sample, a light source coupled to the probe, for irradiating the sample with light from the minute opening, and light from the light source. Light modulation means for amplitude-modulating in synchronization with the oscillation cycle of the probe, a phase shifter for changing the phase or intermittent rate in the light modulation means, displacement detection means for detecting displacement of the probe, A condensing optical system arranged at a position where reflected light can be detected, a photodetector for measuring reflected light intensity, a coarse movement mechanism and a fine movement mechanism for relatively moving the sample and the probe, and In a scanning near-field microscope with a control device that controls the position of the probe, light is irradiated from the probe tip at a position where the probe tip is farther from the state closest to the sample, and lock-in detection of reflected light from the sample at that time Then, the illumination reflection mode was measured.

Also, a probe having a minute opening at the tip, vibrating means for vibrating the tip of the probe horizontally with respect to the sample, vibrating means for vibrating the sample in the vertical direction, A light source for irradiating the sample with light from the opening, light modulation means for amplitude-modulating the light from the light source in synchronization with a vertical oscillation cycle of the probe, and a phase or A phase shifter that changes the intermittent rate, a displacement detection unit that detects the displacement of the probe in the horizontal direction, and a condensing optical system arranged at a position where the reflected light from the sample can be detected.
In a scanning near-field microscope having a photodetector for measuring reflected light intensity, a coarse movement mechanism and a fine movement mechanism for relatively moving the sample and the probe, and a control device for controlling the entire apparatus, the probe tip is a sample. While controlling the distance between the probe tip and the sample by the horizontal amplitude change when approaching the sample, the light from the probe tip is moved by the vertical vibration means at the position where the probe tip is farther from the state closest to the sample. Illuminated, and the reflected light from the sample at that time is subjected to lock-in detection to measure the illumination reflection mode.

Further, the amplitude of the probe or the microcantilever in the vertical direction with respect to the sample is vibrated at 20 nm or more to measure the illumination reflection mode.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The scanning near-field microscope configured as described above condenses light when a gap is formed between the probe tip and the sample, so that light is blocked at the probe tip. And the light collection efficiency is improved. As a result, the S / N ratio of the illumination reflection image is improved.

Furthermore, by greatly changing the amplitude of the probe in the vertical direction with respect to the sample surface by 20 nm or more, the portion blocked by the probe tip is further reduced, and the light collection efficiency is further improved.

In these cases, the resolution is lower than when light is emitted when the probe and the sample come closest to each other, but since the amplitude of the probe is usually 100 nm or less,
This is a region where a near field exists, and a resolution higher than that of a conventional optical microscope can be secured.

Further, by synchronizing the light emitted from the probe with the amplitude cycle of the probe and performing lock-in detection, the S / N ratio is also improved.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an external view of a scanning near-field microscope according to a first embodiment of the present invention.

The probe 1 used in the present embodiment is a bent type probe in which the tip of an optical fiber is sharpened by heat drawing or etching, and is bent in the longitudinal direction of the optical fiber by melting.
A fine opening of about φ5 nm to φ200 nm is provided at the tip of the probe, and an aluminum film is vapor-deposited except for the opening. The rear surface of the probe is mechanically polished to provide a reflection surface.

The probe 1 is fixed to a probe holder 3 having a vibration function by a piezoelectric element 2. For detecting the amplitude of the probe, an optical lever type displacement gauge 6 is used in which the semiconductor laser 4 is applied to a reflection surface provided on the back surface of the probe, and the reflected light is detected by a 4-split detector 5.

On the other hand, the sample 7 is placed on a sample holder 9 provided on the fine movement mechanism 8.

A condensing objective lens 10 used in the illumination reflection mode is provided on the same side of the sample 7 as the probe 1. The objective lens 10 is disposed obliquely to an axis passing through the probe tip and the sample surface so as not to interfere with the probe 1, the optical lever optical system 6, and the cantilever holder 2, and has a focusing direction adjustment function 11. are doing. The optical signal collected by the objective lens 10 on the reflection side passes through the inside of the lens barrel 12, forms an image by the imaging lens 13, and is guided to the light detection unit 14 composed of a photomultiplier.

Fine movement mechanism 8 for scanning sample 7
Uses a cylindrical piezoelectric element. The cylindrical piezoelectric element is provided with electrodes uniformly along the circumference, and has a Z drive unit for controlling the distance between the sample and the probe, and four electrodes on the circumference.
It has a structure in which divided electrodes are provided and an XY drive unit for scanning a sample in the XY direction in a two-dimensional plane is provided.

The sample 7 on the fine movement mechanism 8 is brought closer to the probe tip by the coarse movement mechanism 15. The coarse movement mechanism 15 used a feed screw system driven by a stepping motor. Coarse movement mechanism 15 while vibrating probe 1 near the resonance point
When the sample 7 is brought closer, the amplitude is attenuated due to the interatomic force acting between the probe tip and the sample or intermittent contact. The fine movement mechanism 8 is adjusted so that the amount of attenuation is constant.
By driving in Z, it is possible to keep the distance between the probe 1 and the sample 7 constant. When the scanning is performed by the XY driving unit of the fine movement mechanism 8 while keeping the distance constant, the uneven image in the XY plane can be measured. Further, it is also possible to control the distance by a change in phase due to an interatomic force acting between the probe tip and the sample or intermittent contact.

An argon laser was used as the light source 16 for irradiating the sample 7 with light from the minute opening.
An AO modulator 17 is arranged in front of the argon laser to modulate the light incident on the probe 7, and the light passing through the AO modulator 17 is condensed by the objective lens 18 and coupled to the end of the probe 1. Is done.

The signal 19 for driving the AO modulator is adjusted at a frequency synchronized with the probe excitation signal 20 by a phase shifter 21 for changing the phase and the intermittent rate with respect to the excitation signal 20 to modulate the incident light. Is hung.

On the other hand, the detection signal detected by the photomultiplier 14 is lock-in detected by the lock-in amplifier 22 using the probe vibration signal 20 as a reference signal. When measuring in the illumination reflection mode in the scanning near-field microscope having the above configuration, as shown in FIG. 2, the AO is shifted by the phase shifter so that the evanescent light is irradiated at a point where the probe has moved away from the sample. Adjusting the phase φ and the intermittent ratio (t / T) of the modulation signal of the modulator,
Since a gap is formed between the tip of the probe and the sample surface, the light-collecting efficiency is greatly improved as compared with the case where the probe is closest. Also, since the detected signal is lock-in detected,
The S / N ratio also improves.

At this time, the resolution is lower than the case where the probe and the sample emit light when they come closest to each other.
Since the amplitude of the probe is usually 100 nm or less, it is a region where a near field exists sufficiently, and a resolution higher than that of a conventional optical microscope can be secured.

Further, by increasing the amplitude of the probe within the range where the evanescent light exists, the rate at which the reflected light is blocked at the tip of the probe is further reduced, and the light collection efficiency is improved.

A series of these operations are performed by the control unit 23, and the obtained concavo-convex signal and optical characteristic information are also imaged by the same control unit.

The configuration of the apparatus for measuring the illumination reflection mode by the above method is not limited to the above configuration.

For example, in addition to the optical lever method for detecting the amplitude of the probe, there is a method using a piezoelectric body. In this case, the piezoelectric body is fixed to the probe and vibrated together with the piezoelectric body. When an external force is applied to the probe, the amount of electric charge generated from the piezoelectric body changes. The amplitude is detected based on the amount of change.

Further, in addition to the cylindrical piezoelectric element, a tri-pot type piezoelectric element, a method combining a parallel spring and a piezoelectric element, a voice coil method, and the like are used for the fine movement mechanism.

A light source other than an argon laser can be used as a light source for irradiating the sample with light from the minute opening.

As a light source modulating means, in addition to the method using the AO modulator, a method using a mechanical chopper,
A method of using a semiconductor laser to perform modulation by ON / OFF operation of the laser itself is also conceivable.

FIG. 3 is an external view of a scanning near-field microscope according to a second embodiment of the present invention.

In this embodiment, a cantilever 24 as shown in FIG. 4 is used. The cantilever 24 is made of SiO ₂ and is integrally formed with a cantilever portion 24a and a probe portion 24b provided at the tip of the cantilever portion. The surface where the cantilever tip is provided is made of aluminum except for the tip of the tip.
Coated at 24c. With the above configuration, a cantilever having a small opening 24d at the tip is formed.

The cantilever 24 is fixed to a cantilever holder 26 having a vibrating portion 25 made of a piezoelectric element.

The microscope 27 is arranged on the upper surface side of the cantilever 24, and the light from the light source 28 is guided into the lens barrel 27a of the microscope, condensed by the objective lens 29, and the opening 24d of the cantilever 24 is formed.
To collect light. Since SiO ₂ is optically transparent, the cantilever itself functions as a waveguide, the incident light is guided to the opening 24d, and evanescent light is generated near the opening. In this embodiment, a semiconductor-excited YAG laser is used as a light source, and modulation is performed by driving the laser ON / OFF with a modulation signal.

The construction of the other parts is the same as that of the first embodiment.

Using the scanning near-field microscope configured as described above, irradiation is performed at a position where the tip of the cantilever is away from the sample 7 as in the first embodiment, so that reflected light is blocked at the tip of the cantilever. And the light collection efficiency is improved.

The cantilever used in this embodiment is not limited to the above-mentioned type, and is formed of, for example, silicon nitride, and is arranged from the back side of the cantilever toward the tip of the probe.
A method of securing a waveguide by providing a fine hole in the FIB, or forming a waveguide in the axial direction of the cantilever so that light is guided to the opening provided at the tip of the probe, from the side surface at the end of the cantilever A method of injecting light is conceivable.

FIG. 5 is an external view of a scanning near-field microscope according to a third embodiment of the present invention.

In the present embodiment, the tip of the optical fiber is sharpened by heat drawing or etching, and a fine opening of about φ5 nm to φ200 nm is provided at the tip of the probe. Used.

The probe is arranged by the probe holder 31 such that the long axis direction of the probe 30 is perpendicular to the sample 7. The probe holder 31 is provided with a piezoelectric element 32 for causing the tip of the probe to vibrate the sample 7 in the horizontal and vertical directions. The configurations of the incident light source 16 and the reflected light detecting portion are the same as in the first embodiment. The probe 30 is vibrated in the horizontal direction with respect to the sample by the signal 33 near the resonance frequency of the probe, and is also vibrated with the signal 34 of an arbitrary frequency in the direction perpendicular to the sample. The probe has a piezoelectric body 35 for detecting the horizontal amplitude.
Has been fixed. The change in the horizontal amplitude of the probe 30 is detected as a change in the amount of charge generated from the piezoelectric body 35 fixed to the probe. At this time, the Ar laser 16 incident on the probe is
Is modulated by the signal 36 synchronized with the vertical oscillation period of the signal.

In the case of the present embodiment, the probe 30
The phase shifter 21 adjusts the phase φ of the modulation signal 36 of the AO modulator so that the evanescent light is emitted at a point away from 7.
By adjusting the intermittent ratio (t / T), the light collection efficiency is greatly improved. In addition, the signal detected by the light detection unit 14 is used as a reference signal by using the vertical excitation frequency as a reference signal, and the lock-in amplifier 22 performs lock-in detection.
The ratio also improves.

The means for detecting the amplitude of the probe of this embodiment is not limited to the method using a piezoelectric body, but can be optically detected. In addition to the distance control based on the amplitude change, the distance control can be performed based on a phase change.

In the first to third embodiments, a system in which an objective lens is arranged obliquely is used as a system for condensing reflected light. However, the system for condensing light is not limited to this, and a concave mirror for condensing light is used. A method of assembling a condensing optical system by using a method and a method of condensing light by a condensing lens provided with an escape so as to avoid a probe can also be used.

[0056]

As described above, according to the method for measuring the illumination reflection mode in the scanning near-field microscope of the present invention, the tip is sharpened and the tip has a small opening, and the tip is located in the longitudinal direction of the probe. With a probe bent
Vibrating means for vertically vibrating the probe tip with respect to the sample, a light source coupled to the probe, for irradiating the sample with light from a minute opening, and applying light from the light source to the probe Light modulating means for performing amplitude modulation in synchronization with the oscillation period of the light, a phase shifter for changing the phase or intermittent rate in the light modulating means, displacement detecting means for detecting displacement of the probe, and reflected light from the sample A light collecting optical system arranged at a position capable of detecting the reflected light, a photodetector for measuring the reflected light intensity, a coarse movement mechanism and a fine movement mechanism for relatively moving the sample and the probe, and controlling the entire apparatus. In a scanning near-field microscope having a control device, irradiate light from the probe tip at a position where the tip of the probe is farther from the state closest to the sample,
A configuration was adopted in which reflected light from the sample at that time was lock-in detected. As a result, light is collected when there is a gap between the probe tip and the sample, so that light is less obstructed at the probe tip, improving the light collection efficiency and improving the S / N ratio of the illumination reflection image. Is improved.

Also, a probe having a sharpened tip, a micro opening provided at the tip of the probe, a micro cantilever having a waveguide for transmitting light to the micro opening, Vibration means for vibrating the probe in the vertical direction, a light source coupled to the microcantilever, and a light source for irradiating the sample with light from the minute opening, coupling means for the microcantilever, and the light source Light modulating means for modulating the amplitude of the light in synchronization with the oscillation cycle of the micro cantilever, a phase shifter for changing the phase or intermittent rate in the light modulating means, and a displacement detecting means for detecting a displacement of the micro cantilever And, a condensing optical system arranged at a position capable of detecting the reflected light from the sample, a photodetector for measuring the intensity of the reflected light, and the sample and the In a scanning near-field microscope having a coarse movement mechanism and a fine movement mechanism for relatively moving the microcantilever, and a control device for controlling the entire apparatus, light is emitted from the probe tip at a position where the probe tip is farther from the state closest to the sample. Irradiation was performed, and the reflected light from the sample at that time was configured to be lock-in detected.

In this case as well, light is condensed when a gap is formed between the probe tip and the sample, so that the light is less obstructed by the probe tip, the light collection efficiency is improved, and the illumination reflection image is improved. S / N ratio is improved.

A probe having a sharpened tip and a fine opening at the tip, vibrating means for vibrating the probe tip horizontally with respect to the sample, vibrating means for vibrating vertically in the sample, and Coupled to
A light source for irradiating the sample with light from the minute opening, light modulation means for amplitude-modulating the light from the light source in synchronization with a vertical oscillation period of the probe, and a phase in the light modulation means Or a phase shifter for changing the intermittent rate, a displacement detecting means for detecting horizontal and vertical displacements of the probe, a condensing optical system arranged at a position capable of detecting reflected light from the sample, In a scanning near-field microscope having a photodetector for measuring light intensity, a coarse movement mechanism and a fine movement mechanism for relatively moving the sample and the probe, and a control device for controlling the entire apparatus, the probe tip is attached to the sample. While controlling the distance between the probe tip and the sample by the horizontal amplitude change when approaching, the probe tip was closest to the sample by the vertical vibration means. In away position than state, light is irradiated from the probe tip, and configured so as to lock-in detecting the light reflected from the sample at that time. as a result,
Light is collected when there is a gap between the tip of the probe and the sample, so that light is less obstructed at the tip of the probe, improving the light collection efficiency and improving the S / N ratio of the illumination reflection image. .

Further, by greatly changing the amplitude of the probe in the vertical direction with respect to the sample surface at 20 nm or more, the portion blocked by the probe tip is further reduced, and the light collection efficiency is further improved.

In these cases, the resolution is lower than when light is emitted when the probe and the sample come closest to each other, but since the amplitude of the probe is usually 100 nm or less,
This is a region where a near field exists, and a resolution higher than that of a conventional optical microscope can be secured.

[Brief description of the drawings]

FIG. 1 is an external view showing an apparatus configuration of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a locus of amplitude of a probe and a light modulation signal.

FIG. 3 is an external view showing an apparatus configuration of a second embodiment of the present invention.

FIG. 4 is a sectional view of a cantilever used in a second embodiment of the present invention.

FIG. 5 is an external view showing an apparatus configuration of a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Probe 3 Probe holder 6 Optical lever type displacement meter 7 Sample 8 Fine movement mechanism 9 Sample holder 10 Condensing objective lens 14 Photodetector 15 Coarse movement mechanism 16 Light source 17 AO modulator 18 Objective lens 19 Modulation signal 20 Excitation signal 21 Transfer Phaser 22 Lock-in amplifier 23 Controller 24 Cantilever 26 Cantilever holder 27 Microscope 28 Light source 29 Objective lens 30 Straight type probe 31 Probe holder 32 Vibration piezoelectric element 33 Horizontal vibration signal 34 Vertical vibration signal 35 Detection Piezoelectric element for 36 Modulation signal

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference)

Claims (4)

[Claims] 1. A probe having a sharpened tip, a fine opening in the tip, and a tip bent in the longitudinal direction of the probe, and a probe for vibrating the tip of the probe in a direction perpendicular to a sample. And a light source coupled to the probe, for irradiating the sample with light from the minute opening, and a light modulation unit for amplitude-modulating the light from the light source in synchronization with the oscillation cycle of the probe. A phase shifter that changes a phase or an intermittent rate in the light modulation unit, a displacement detection unit that detects a displacement of the probe, and a condensing optical system arranged at a position where reflected light from a sample can be detected. In a scanning near-field microscope having a photodetector for measuring reflected light intensity, a coarse movement mechanism and a fine movement mechanism for relatively moving the sample and the probe, and a control device for controlling the entire apparatus. Illumination in a scanning near-field microscope characterized by irradiating light from the probe tip at a position where the probe tip is farther from the sample closest to the sample and lock-in detecting the reflected light from the sample at that time How to measure reflection mode. 2. A probe having a sharpened tip, a micro-opening provided at the tip of the probe, a micro-cantilever having a waveguide for transmitting light to the micro-opening, and Vibrating means for vibrating the probe vertically,
A light source coupled to the microcantilever, for irradiating the sample with light from the minute opening,
Coupling means with a microcantilever, light modulation means for amplitude-modulating light from the light source in synchronization with the oscillation cycle of the microcantilever, and a phase shifter for changing the phase or intermittent rate in the light modulation means A displacement detecting means for detecting the displacement of the microcantilever, a condensing optical system arranged at a position capable of detecting the reflected light from the sample, a photodetector for measuring the intensity of the reflected light, and the sample In a scanning near-field microscope having a coarse movement mechanism and a fine movement mechanism for relatively moving the microcantilever, and a control device for controlling the entire apparatus, at a position where the probe is farther from the state closest to the sample, a minute opening is formed. Illumination in a scanning near-field microscope characterized by irradiating light from the sample and lock-in detecting the reflected light from the sample at that time. Method of measuring the Shon reflection mode. 3. A probe whose tip is sharpened and which has a fine opening at the tip, vibrating means for vibrating the probe tip in a horizontal direction with respect to a sample, vibrating means for vibrating in a vertical direction with respect to a sample, A light source coupled to the probe, for irradiating the sample with light from the minute opening, light modulation means for amplitude-modulating the light from the light source in synchronization with a vertical oscillation cycle of the probe, A phase shifter that changes the phase or the intermittent rate in the light modulation unit, and a displacement detection unit that detects a horizontal displacement of the probe,
A condensing optical system arranged at a position where reflected light from the sample can be detected, and a photodetector for measuring reflected light intensity,
In a scanning near-field microscope having a coarse movement mechanism and a fine movement mechanism for relatively moving the sample and the probe, and a control device for controlling the entire apparatus, the probe is driven by a change in amplitude in a horizontal direction when the probe tip is brought close to the sample. While controlling the distance between the tip and the sample, light is emitted from the probe tip at a position where the probe tip is farther from the state where the probe tip is closest to the sample by the vertical vibration means, and the reflected light from the sample at that time is locked A method for measuring an illumination reflection mode in a scanning near-field microscope, wherein the illumination reflection mode is detected. 4. The illumination reflection in a scanning near-field microscope according to claim 1, wherein the vertical amplitude of the probe tip or the microcantilever probe with respect to the sample is vibrated at 20 nm or more. Mode measurement method.