KR102256790B1 - Optical aligner of the raman-atomic force microscope(afm) - Google Patents

Abstract

The optical axis aligner of a Raman-atomic force microscope (AFM) according to an embodiment includes an optical microscope unit disposed on an upper side of a sample substrate and a Raman spectrometer unit disposed on a lower side of the sample substrate, the The optical microscope unit includes a first lens disposed on the upper side of the sample, and the Raman spectrometer unit includes a second lens disposed on the lower side of the sample. Alternatively, the optical axes of the lenses are aligned in a line by controlling the pitch.

Description

Optical axis aligner of Raman-atomic force microscope {OPTICAL ALIGNER OF THE RAMAN-ATOMIC FORCE MICROSCOPE(AFM)}

The following examples relate to an optical axis aligner of a Raman-atomic force microscope.

Raman spectroscopy relates to a spectroscopic technique used to observe vibration, rotation and other low-frequency modes in a system. This is usually due to Raman scattering of monochromatic light such as lasers in the visible, near-infrared region or near-infrared region.

When light passes through a medium, some of the light is scattered and deviated from the direction of travel and proceeds in the other direction. The elastic process in which the scattered light is scattered while maintaining its original energy is called Rayleigh scattering, and the energy is called Rayleigh scattering. The inelastic process that is scattered while losing or gaining is called Raman Scattering or inelastic scattering. When a molecule receives light, the molecule is excited to an excited state, and the molecule in this excited state is brought down to the ground state in three ways. First, when all the energy of the incident light source is released and falls to the ground state, light of the same energy as the incident light source is scattered and emitted. This is the Rayleigh scattering. On the other hand, the case of returning to the ground state after absorbing or releasing the vibrational energy of the molecule is called Raman scattering. At this time, the transition of the vibration state occurs. The case where the molecule returns to the ground state after absorbing the vibration energy is called the Stokes effect. At this time, since the energy of the radiation is absorbed by the molecule, less energy than the incident light source, that is, light with a longer wavelength is scattered. On the other hand, the case where the vibration energy of the molecule is released and returns to the ground state is called the anti-Stokes effect, and since the radiation is in the state of obtaining energy from the molecule, light with a higher energy than the incident light source, that is, light with a shorter wavelength, is scattered. Comes out. Energy exchange between the incident light source and the material occurs through the Raman scattering process. The energy absorbed or emitted by a substance is closely related to the molecular structure constituting each substance, and the scattered light due to Raman scattering is unique to each substance, so analyzing the scattered light can infer the molecular structure of the substance. In general, this change can be measured by observing how much energy the light loses or gains before and after scattering. The change of the spectrum before and after the scattering is referred to as Raman Shift. The Raman shift corresponds to the vibration frequency of the molecule.

Such Raman spectroscopy is a method of performing qualitative and quantitative analysis of each substance by measuring a substance's own vibration spectrum and finding the substance's own spectrum. In other words, Raman scattering is the inelastic scattering of photons that can provide the vibrational fingerprints of molecules.

When such Raman spectroscopy is combined with AFM, an amplified Raman signal is generated by being limited to a region in contact with the AFM probe, enabling high-resolution Raman spectroscopy analysis. This method is called Tip-Enhances Raman Spectroscopy (TERS). Probe-enhanced Raman spectroscopy is a spectroscopic method that captures a Raman spectrum of several tens of nm around a tip by using an electric field that increases very strongly at the tip of a noble-metal tip.

Korean Patent No. 10-2012-0006845 discloses a surface-enhanced Raman scattering particle and an analysis system using the same.

An object according to an embodiment is to provide an optical axis aligner of a Raman-atomic force microscope capable of accurately matching the optical axis of an upper OPU (Optical pick-up) and a lower OPU in order to accurately irradiate a Raman light source at the bottom of the AFM probe. To provide.

An object according to an embodiment is to provide an optical axis aligner of a Raman-atomic force microscope capable of precisely controlling an optical axis so that the positions of the AFM probe and the Raman light source are matched and capable of being manufactured at low cost.

The optical axis aligner of a Raman-atomic force microscope (AFM) according to an embodiment includes an optical microscope unit disposed on an upper side of a sample substrate and a Raman spectrometer unit disposed on a lower side of the sample substrate, the The optical microscope unit includes a first lens disposed on the upper side of the sample, and the Raman spectrometer unit includes a second lens disposed on the lower side of the sample. Alternatively, the optical axes of the lenses are aligned in a line by controlling the pitch.

The optical microscope unit includes a first driving element capable of moving the position of the first lens with respect to the X axis, and the Raman spectrometer unit includes a second driving element capable of moving the position of the second lens with respect to the Y axis. do.

The optical microscope unit includes a third driving element for controlling a movement of a roll or a pitch of the first lens, and the Raman spectrometer unit includes a roll or a pitch of the second lens. And a fourth driving element for controlling the movement.

Each of the first driving element and the second driving element may be a step motor, and each of the third driving element and the fourth driving element may be a voice coil motor.

The optical microscope unit includes a first light source for irradiating a laser to the first lens, an AFM probe for scanning the sample with a laser passing through the first lens, a first laser power sensor for detecting the intensity of the laser, and the AFM A first position sensor for measuring a position of a laser reflected from the probe, and a CMOS sensor for converting the laser reflected from the AFM probe into an electric signal may be further included.

The Raman spectrometer unit includes a second light source that irradiates a Raman laser capable of causing Raman scattering to the second lens, a second laser power sensor that detects the intensity of the Raman laser irradiated from the second light source, and at one end of the AFM probe. A second position sensor for measuring the position of the reflected Raman laser, a long pass filter for passing a Raman signal amplification (SERS, Surface Enhanced Raman Spectrometer) generated at one end of the AFM probe, and the long pass filter. A Raman spectrometer for measuring the laser Raman spectrum of the passed Raman signal amplification may be further included.

Optical axes of the first lens and the second lens by driving elements may be aligned such that a Raman laser emitted from the second light source is irradiated to one end of the AFM probe.

A method of controlling an optical axis aligner of a Raman-atomic force microscope (AFM) according to an embodiment includes a position of a first lens disposed on an upper side of a sample substrate with respect to the X axis, and a roll Or controlling the pitch, controlling the position of the second lens disposed under the sample substrate with respect to the Y axis, the roll or the pitch, and the first lens and the second lens It includes the step of aligning the optical axes of the line.

In this case, controlling the position, roll, or pitch of the first lens with respect to the X-axis includes moving the position of the first lens with respect to the X-axis using a stepper motor and voice It may include controlling a movement of a roll or a pitch of the first lens using a coil motor.

In addition, the step of controlling the position, roll, or pitch of the second lens with respect to the Y-axis may include moving the position of the second lens with respect to the Y-axis using a step motor, and the voice coil. It may include controlling a movement of a roll or a pitch of the second lens using a motor.

In the step of aligning the optical axes of the first lens and the second lens in a line, a Raman laser passing through the second lens may be irradiated to one end of an AFM probe positioned under the first lens.

The optical axis aligner of the Raman-atomic force microscope according to an embodiment may accurately match the optical axis of the upper OPU (Optical Pick-up) and the lower OPU in order to accurately irradiate the Raman light source at the lower end of the AFM probe.

An optical axis aligner of a Raman-atomic force microscope capable of precisely controlling an optical axis such that the AFM probe according to an exemplary embodiment and the position of the Raman light source are matched may be manufactured at low cost.

1 shows the structure of an optical axis aligner of a Raman-atomic force microscope according to an embodiment.
2 shows the structure of an optical microscope part of an optical axis aligner of a Raman-atomic force microscope according to an embodiment.
3 shows the structure of a Raman spectrometer part of an optical axis aligner of a Raman-atomic force microscope according to an embodiment.
4 shows a state in which movements of the first lens of the optical microscope unit and the second lens of the Raman spectrometer unit are controlled.
5 is a flowchart illustrating a method of controlling an optical axis aligner of a Raman-atomic force microscope according to an exemplary embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. The following description is one of several aspects of the embodiments, and the following description forms part of a detailed description of the embodiments.

However, in describing one embodiment, detailed descriptions of known functions or configurations will be omitted in order to clarify the gist of the present invention.

In addition, terms or words used in this specification and claims should not be interpreted in a conventional or dictionary meaning, and the inventor may appropriately define the concept of terms in order to describe his own invention in the best way. Based on the principle that there is a Raman-atomic force microscope according to an embodiment, it should be interpreted as a meaning and concept consistent with the technical idea of an optical axis aligner and a method of controlling the same.

Therefore, the embodiments described in the present specification and the configuration shown in the drawings are only the most preferred embodiment of the optical axis aligner of the Raman-atomic force microscope according to an embodiment and a method of controlling the same, and according to an embodiment Since it does not represent all the technical ideas of the optical axis aligner of the Raman-atomic force microscope and the method of controlling the same, it should be understood that there may be various equivalents and modified examples that can replace them at the time of the present application. .

1 shows the structure of an optical axis aligner of a Raman-atomic force microscope according to an embodiment. Specifically, FIG. 2 shows the structure of the optical microscope part of the optical axis aligner of the Raman-atomic force microscope according to an embodiment, and FIG. 3 is the structure of the Raman spectrometer part of the optical axis aligner of the Raman-atomic force microscope according to an embodiment. Represents. 4 shows a state in which the movement of the first lens of the optical microscope unit and the second lens of the Raman spectrometer unit are controlled, and FIG. 5 is a flow chart of a method of controlling the optical axis aligner of the Raman-atomic force microscope according to an embodiment. .

Referring to FIG. 1, the optical axis aligner 10 of a Raman-atomic force microscope (AFM) according to an embodiment is an optical microscope unit 200 disposed above the sample substrate 100 And a Raman spectrometer unit 300 disposed below the sample substrate 100, the optical microscope unit 200 including a first lens 210 disposed above the sample, and a Raman spectrometer unit 300 Includes a second lens 310 disposed under the sample, and by controlling the position, roll, or pitch of the lenses 210 and 310 on the X-axis or Y-axis with respect to the sample substrate. The optical axes of the lenses 210 and 310 are aligned in a line.

The optical microscope unit 200 includes a first driving element (not shown) capable of moving the position of the first lens 210 with respect to the X axis, and the Raman spectrometer unit 300 is A second driving element (not shown) capable of moving a position with respect to the Y axis may be included.

In addition, the optical microscope unit 200 includes a third driving element (not shown) for controlling the movement of the roll or pitch of the first lens 210, and the Raman spectrometer unit 300 is 2 It may include a fourth driving element (not shown) that controls the movement of the roll or pitch of the lens 310.

In this case, the first driving element and the second driving element may be a step motor, and the third driving element and the fourth driving element may be a voice coil motor, respectively.

Specifically, referring to FIG. 2, the optical microscope unit 200 includes a first light source 220 that irradiates a laser to the first lens 210, and scans a laser that has passed through the first lens 210 to the sample. The AFM probe 230, the first laser power sensor 240 for detecting the intensity of the laser, the first position sensor 250 for measuring the position of the laser reflected from the AFM probe 230, the reflection from the AFM probe 230 It may further include a CMOS sensor 260 for converting the laser into an electrical signal.

In the optical microscope unit 200 having the above configuration, the laser emitted from the first light source 220 is reflected by the first mirror 280 and is directed toward the first beam splitter 290. The laser reflected from the first beam splitter 290 passes through the first lens 210 and is concentrated in the AFM probe 230 and scanned into the sample. In this case, a part of the laser may pass through the first beam splitter 290 and be transmitted to the first laser power sensor 240. Thereafter, the laser reflected from the sample passes through the first lens 210 and a part of the laser is reflected by the first beam splitter 290 and transmitted to the first position sensor 250. In addition, a part of the reflected laser is transmitted to the CMOS sensor 260 through the third lens 270 disposed between the first beam splitter 290 and the CMOS sensor 260.

The first lens 210, the first light source 220, the first laser power sensor 240, the first position sensor 250, the first mirror 280, the first beam splitter 290 is the upper OPU ( Optical pick-up) can be configured.

In addition, the optical axis of the laser emitted from the first light source 220 and passing through the first lens 210 is changed in position (one degree of freedom) with respect to the X-axis relative to the sample substrate by the first driving element. The roll or pitch movement (2 degrees of freedom) may be controlled by the third driving element.

Referring to FIG. 3, the Raman spectrometer 300 includes a second light source 320 that irradiates a Raman laser capable of causing Raman scattering to the second lens 310, and a Raman radiated from the second light source 320. The second laser power sensor 330 that detects the intensity of the laser, the second position sensor 340 that measures the position of the Raman laser reflected from one end of the AFM probe 230, generated at one end of the AFM probe 230 A long pass filter (350) passing through a Raman signal amplification (SERS, Surface Enhanced Raman Spectrometer) and a Raman spectrometer (360) measuring a laser Raman spectrum of the Raman signal amplification passing through the long pass filter are further included. can do.

In the Raman spectrometer unit 300 having the above configuration, the Raman laser emitted from the second light source 320 is reflected by the second mirror 370 and directed toward the second beam splitter 380. The Raman laser reflected from the second beam splitter 380 passes through the second lens 310 and is scanned onto one end of the AFM probe 230. In this case, a part of the Raman laser may pass through the second beam splitter 380 and be transmitted to the second laser power sensor 330. Thereafter, the Raman laser reflected from one end of the AFM probe 230 passes through the second lens 310, and a part of the Raman laser is reflected from the second beam splitter 380 and transmitted to the second position sensor 340. In addition, a part of the reflected Raman laser passes through the long pass filter 350 disposed between the second beam splitter 380 and the third mirror 390 and is reflected by the third mirror 390 and then It is transmitted to the spectrometer 360. In this case, the reflected Raman laser may be a Raman signal amplification (SERS, Surface Enhanced Raman Spectrometer).

The second lens 310, the second light source 320, the second laser power sensor 330, the second position sensor 340, the second mirror 370, and the second beam splitter 380 are OPU ( Optical pick-up) can be configured.

In addition, the optical axis of the Raman laser emitted from the second light source 320 and passing through the second lens 310 is changed in position (one degree of freedom) with respect to the Y-axis relative to the sample substrate by the second driving element. The roll or pitch movement (2 degrees of freedom) may be controlled by the fourth driving element.

That is, referring to FIG. 4, an X-axis and a Y-axis may be formed on a two-dimensional plane parallel to the plane of the sample substrate 100, and the first lens 210 of the optical microscope unit 200 is the X The position relative to the axis can be controlled. In addition, it is possible to control the movement of the roll or pitch at the same time. In addition, the position of the second lens 310 of the Raman spectrometer unit 300 with respect to the Y-axis may be controlled, and a movement of a roll or a pitch may be controlled at the same time.

The optical axis aligner of the Raman-atomic force microscope including the configurations described above may generate a nano-Raman phenomenon at one end of the AFM probe. That is, the Raman emitted from the second light source is accurately irradiated with the laser irradiated from the first light source through the first lens of the upper OPU, and the optical axes of the first lens and the second lens are accurately aligned. The laser can be accurately irradiated to one end of the AFM probe. At this time, the position, roll, or pitch of the first lens with respect to the X axis is controlled using a step motor and a voice coil motor, and the position of the second lens with respect to the Y axis, a roll, or By controlling the pitch using a step motor and a voice coil motor, it is possible to quickly and accurately align the optical axes of the two lenses.

Referring to FIG. 5, a method of controlling an optical axis aligner of a Raman-atomic force microscope (AFM) according to an embodiment is provided with respect to the X axis of the first lens disposed on the upper side of the sample substrate. Controlling the position, roll, or pitch (S100), controlling the position, roll, or pitch of the second lens disposed on the lower side of the sample substrate with respect to the Y axis ( S200) and aligning the optical axes of the first lens and the second lens in a line (S300).

In this case, the step of controlling the position, roll, or pitch of the first lens with respect to the X-axis (S100) is a step of moving the position of the first lens with respect to the X-axis using a stepper motor ( S110) and controlling the movement of the roll or pitch of the first lens using the voice coil motor (S120).

In addition, the step of controlling the position, roll, or pitch of the second lens with respect to the Y axis (S200) is a step of moving the position of the second lens with respect to the Y axis using a step motor (S210). ) And controlling the movement of the roll or pitch of the second lens using a voice coil motor (S220).

In the step S300 of aligning the optical axes of the first lens and the second lens in a line (S300), a Raman laser passing through the second lens may be irradiated to one end of the AFM probe positioned under the first lens.

Through the optical axis aligner of the Raman-atomic force microscope and a method of controlling the same, the upper OPU (Optical pick-up) and the lower OPU optical axis are accurately adjusted to accurately irradiate the Raman light source at the bottom of the AFM probe. Can match.

In addition, it is possible to manufacture an optical axis aligner of a Raman-atomic force microscope capable of precisely controlling the optical axis so that the AFM probe and the position of the Raman light source are matched at low cost.

As described above, in the embodiment, the embodiment has been described by specific items such as specific components and the limited embodiment and drawings, but this is provided to help overall understanding. In addition, the present invention is not limited to the above-described embodiments, and various modifications and variations are possible from these descriptions by those of ordinary skill in the field to which the present invention pertains. Therefore, the spirit of the present invention is limited to the above-described embodiments and should not be defined, and all things that have equivalent or equivalent modifications to the claims as well as the claims to be described later belong to the scope of the inventive concept.

10: Raman-atomic force microscope optical axis aligner
100: sample substrate
200: optical microscope unit
210: first lens
220: first light source
230: AFM probe
240: first laser power sensor
250: first position sensor
260: CMOS sensor
270: third lens
280: first mirror
290: first beam splitter
300: Raman spectrometer unit
310: second lens
320: second light source
330: second laser power sensor
340: second position sensor
350: long pass filter
360: Raman spectrometer
370: second mirror
380: second beam splitter
390: third mirror

Claims (10)

In the optical axis aligner of a Raman-atomic force microscope (RAMAN-ATOMIC FORCE MICROSCOPE, AFM),
An optical microscope unit disposed on the upper side of the sample substrate; And
A Raman spectrometer unit disposed under the sample substrate;
Including,
The optical microscope unit includes a first lens disposed above the sample, and the Raman spectrometer unit includes a second lens disposed below the sample,
The optical microscope unit,
A first driving element capable of moving the position of the first lens with respect to the X axis;
A third driving element controlling a movement of a roll or a pitch of the first lens;
A first light source for irradiating a laser to the first lens; And
An AFM probe for scanning the sample with a laser passing through the first lens;
Including,
The Raman spectrometer unit,
A second driving element capable of moving the position of the second lens with respect to the Y axis;
A fourth driving element controlling a movement of a roll or a pitch of the second lens; And
A second light source for irradiating a Raman laser capable of generating Raman scattering toward the second lens;
Including,
Optical axes of the first lens and the second lens are aligned by driving elements, and a Raman laser emitted from the second light source is irradiated to one end of the AFM probe
Optical axis aligner in Raman-atomic force microscope.
delete delete The method of claim 1,
Each of the first driving element and the second driving element is a step motor,
The third driving element and the fourth driving element are voice coil motors, respectively, the optical axis aligner of the Raman-atomic force microscope.
The method of claim 4,
The optical microscope unit,
A first laser power sensor detecting the intensity of the laser;
A first position sensor measuring a position of a laser reflected from the AFM probe; And
A CMOS sensor that converts the laser reflected from the AFM probe into an electrical signal;
Further comprising, Raman-Atomic force microscope optical axis aligner.
The method of claim 5,
The Raman spectrometer unit,
A second laser power sensor detecting the intensity of the Raman laser irradiated from the second light source;
A second position sensor for measuring a position of a Raman laser reflected from one end of the AFM probe after the Raman laser passes through the second lens and is scanned at one end of the AFM probe;
A long pass filter for passing Raman signal amplification (SERS) generated at one end of the AFM probe; And
A Raman spectrometer measuring a laser Raman spectrum of a Raman signal amplification passing through the long pass filter;
Further comprising, Raman-Atomic force microscope optical axis aligner.
delete In the method of controlling an optical axis aligner of a Raman-atomic force microscope (AFM),
Controlling a position, a roll, or a pitch of the first lens disposed on the upper side of the sample substrate with respect to the X axis;
Controlling a position, a roll, or a pitch with respect to the Y-axis of the second lens disposed under the sample substrate; And
Aligning optical axes of the first lens and the second lens in a line;
Including,
The optical axis aligner,
A first driving element capable of moving the position of the first lens with respect to the X axis;
A third driving element for controlling a movement of a roll or a pitch of the first lens;
A first light source irradiating a laser to the first lens;
An AFM probe for scanning a sample with a laser passing through the first lens;
A second driving element capable of moving the position of the second lens with respect to the Y axis;
A fourth driving element controlling a movement of a roll or a pitch of the second lens; And
A second light source for irradiating a Raman laser capable of generating Raman scattering toward the second lens;
Including,
The step of aligning the optical axes of the first lens and the second lens in a line includes irradiating a Raman laser passing through the second lens to one end of an AFM probe positioned under the first lens,
Way.
The method of claim 8,
The step of controlling the position, roll, or pitch of the first lens with respect to the X-axis,
Moving a position of the first lens with respect to the X axis using a step motor that is the first driving element; And
Controlling a movement of a roll or a pitch of the first lens using a voice coil motor that is the third driving element;
Including,
Controlling the position, roll, or pitch of the second lens with respect to the Y axis,
Moving the position of the second lens with respect to the Y axis using a step motor that is the second driving element; And
Controlling a movement of a roll or a pitch of the second lens using a voice coil motor that is the fourth driving element;
Including, the method.
delete

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