Scan type probe microscope system and method for manufacturing the same

Abstract

To provide a device which identifies the types of chemical bonds with atomic-level spatial resolution of a material.SOLUTION: A scan type probe microscope device comprises: a detection unit which has at least one probe that is arranged in contact or non-contact with a detection object; and a control unit which controls the detection unit. The probe has a function that changes electromagnetic waves into electrical signals. The probe is controlled by the control unit, captures the electromagnetic waves in the vicinity of the target object and converts them into the electrical signals to highly accurately identify chemical bonds in the target object.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a probe for use in a scanning probe microscope system and a method for manufacturing the same. [Background technology]

[0002] Scanning probe microscopes have atomic-level resolution and are widely used as powerful analytical tools in the analytical field. For example, scanning tunneling microscopes and atomic force microscopes are widely used to observe atomic images and crystal lattice images. Scanning near-field microscopes can also map molecular species by measuring the spectrum of molecules beyond the diffraction limit of light. The spatial resolution of scanning near-field microscopes has achieved several nanometers. However, since the length of the chemical bond of a molecule is shorter than one nanometer, it is still impossible to obtain a scanning near-field microscope image of each chemical bond even with the techniques of Patent Document 1, Patent Document 2, Non-Patent Document 1, and Non-Patent Document 2. The reason for this is that the measurement principle of the current scanning near-field microscope uses reflection or scattering of light, and a detector for reflected or scattered light is installed outside, so the dynamic range of light detection is narrow. There is a problem with conventional scanning probe microscopes in which the light detector is installed at a location away from the scanning probe. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2014-033844 A1, Scanning probe microscope and measurement method using the same [Patent Document 2] Patent No. 6949673, Near-field scanning probe microscope, probe for scanning probe microscope, and sample observation method [Non-patent literature]

[0004] [Non-Patent Document 1] Nano Letters(USA), 2022, Vol. 22, No. 4, P1525-1533,Vibrational Properties in Highly Strained Hexagonal Boron Nitride Bubbles, [Non-Patent Document 2] Nature Communications(USA), 2022, Vol. 13, Article No.: 2586, On-chip nanophotonic topological rainbow Summary of the Invention [Problem to be solved by the invention]

[0005] Even with the above Patent Document 1, Patent Document 2, Non-Patent Document 1, and Non-Patent Document 2, it was not possible to accurately identify the chemical bonds between atoms that constitute a molecule at the order of one chemical bond.

[0006] The present invention has been made in view of the above, and an object of the present invention is to provide a scanning probe microscope apparatus capable of identifying chemical bonds in a detection target with high accuracy. [Means for solving the problem]

[0007] (1) The present invention provides a scanning probe microscope apparatus capable of identifying chemical bonds in a detection object with high accuracy, comprising a detection unit having at least one probe that is placed in contact or non-contact with the detection object, and a control unit that controls the detection unit, wherein the probe has a function of converting electromagnetic waves into electrical signals, and the probe is controlled by the control unit. The scanning probe microscope apparatus provides a scanning probe microscope apparatus capable of identifying chemical bonds in the object with high accuracy by capturing electromagnetic waves in the vicinity of the object and converting them into electrical signals.

[0008] (2) (1) is characterized in that the electromagnetic wave signal in the vicinity of the detection object is a higher-order harmonic including the second order and higher-order harmonic of the electromagnetic wave irradiated from the light source unit.

[0009] (3) In the scanning probe microscope of (1), the probe having the function of converting the electromagnetic wave into an electric signal is configured to include, from the outside, at least a tip portion of the probe, a conductor layer, a photoelectric conversion layer, and a conductor layer.

[0010] (4) It is desirable that the photoelectric conversion layer of (3) be composed of a PN junction of at least one P-type layer selected from silicon and germanium and at least one N-type layer selected from silicon and germanium.

[0011] (5) It is desirable that the photoelectric conversion layer of (3) be composed of a PN junction of at least one P-type layer selected from copper indium selenide [CuInSe2] and copper indium gallium selenide [Cu(InGa)Se2] and at least one N-type layer selected from cadmium sulfide (CdS), zinc sulfide (ZnS), and zinc oxide (ZnO).

[0012] (1) (2) (3) (4) (5) (6) In the scanning probe microscope of (1), the probe having the function of converting the electromagnetic wave into an electric signal is configured to include, from the outside, at least a tip portion of the probe, a conductive layer, a pyroelectric layer, and a conductive layer.

[0013] (6) (7) (8) (9) (10) (7) It is desirable that the pyroelectric layer of (6) is composed of at least one layer selected from lead zirconate titanate (PZT), lead titanate (PbTiO3), barium titanate (BaTiO3), and L-alanine-doped deuterated triglycine sulfate (DLaTGS).

[0014] (8) In the scanning probe microscope of (1), the probe having the function of converting the electromagnetic wave into an electric signal is configured to include, from the outside, at least a tip portion of the probe, a conductive layer, a photoconductor layer, and a conductive layer.

[0015] (9) It is desirable that the photoconductor layer (8) is composed of at least one layer selected from cadmium sulfide (CdS), cadmium selenide (CdSe), zinc sulfide (ZnS), zinc oxide (ZnO), lead sulfide (PbS), cadmium mercury telluride (CdHgTe), and selenium (Se).

[0016] (10) In the scanning probe microscope of (8), the probe having the function of converting the electromagnetic wave into an electric signal is configured such that the photoconductor layer includes a quantum well structure.

[0017] (11) In the scanning probe microscope of (8), the probe having the function of converting the electromagnetic wave into an electric signal is configured such that the photoconductor layer includes a quantum dot structure.

[0018] (12) In the scanning probe microscope of (8), the probe capable of converting the electromagnetic wave into an electric signal is configured such that the photoconductor layer includes a type II superlattice structure. Effect of the Invention

[0019] According to the present invention, it is possible to provide a detection device capable of detecting at least one piece of information regarding the shape of a detection target, absorption of electromagnetic waves, and emission of electromagnetic waves with high accuracy.

[0020] Furthermore, while known scanning probe microscopes observe the surface of a sample by measuring the atomic force or the current flowing between the probe and the sample, the electromagnetic wave detection device of the present invention can detect at least one of the shape of the detection target, the absorption of electromagnetic waves, and the emission of electromagnetic waves with high accuracy.

[0021] Furthermore, according to the present invention, if the measurement is performed while controlling the position of the probe, it is not necessary to utilize the scattering of electromagnetic waves, and therefore at least one of the behaviors of the shape of the minute area to be detected, the absorption of electromagnetic waves, and the emission of electromagnetic waves can be detected with high accuracy. Therefore, molecular bonds can be distinguished from one another. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram showing a configuration of a scanning probe microscope apparatus according to an embodiment of the present invention.

[0023] [Diagram 2] FIG. 1 is a diagram showing the configuration of a probe for a scanning probe microscope apparatus according to one embodiment of the present invention, showing a structure in which the tip portion includes, from the outside, a conductor layer, a photoelectric conversion layer, and another conductor layer.

[0024] [Diagram 3] FIG. 2 is a diagram showing the configuration of a probe for a scanning probe microscope apparatus according to one embodiment of the present invention, showing a structure in which the tip portion includes, from the outside, a conductive layer, a pyroelectric layer, and a conductive layer.

[0025] [Figure 4] FIG. 1 is a diagram showing the configuration of a probe for a scanning probe microscope apparatus according to one embodiment of the present invention, showing a structure in which the tip portion includes, from the outside, a conductive layer, a photoconductor layer, and a conductive layer.

[0026] [Diagram 5] FIG. 1 is a diagram showing the configuration of a probe for a scanning probe microscope apparatus according to one embodiment of the present invention, in which the tip portion is configured to include, from the outside, a conductive layer, a photoconductor layer, and a conductive layer, and the photoconductor layer is configured to include a quantum well structure.

[0027] [Figure 6] FIG. 1 is a diagram showing the configuration of a probe for a scanning probe microscope apparatus according to one embodiment of the present invention, in which the tip portion is configured to include, from the outside, a conductive layer, a photoconductor layer, and a conductive layer, and the photoconductor layer is configured to include a quantum dot structure.

[0028] [Figure 7]FIG. 1 is a diagram showing the configuration of a probe for a scanning probe microscope apparatus according to one embodiment of the present invention, in which the tip portion is configured to include, from the outside, a conductive layer, a photoconductor layer, and a conductive layer, and the photoconductor layer is configured to include a type II superlattice structure.

[0029] [Figure 8] FIG. 1 shows the configuration of a scanning probe microscope apparatus according to an embodiment of the present invention, and shows a structure for storing at least a probe 100, a sample holder 500, and a detection target 600 in a chamber so that at least one of the temperature, atmosphere, and degree of vacuum can be controlled.

[0030] [Figure 9] FIG. 1 is a diagram showing the configuration of a scanning probe microscope apparatus according to an embodiment of the present invention, and is a diagram showing a structure for irradiating an electromagnetic wave from the back side of a sample holder.

[0031] [Figure 10] FIG. 1 is a diagram showing the configuration of a scanning probe microscope apparatus according to an embodiment of the present invention, and is a diagram showing a structure in which a thin film of metal nanoparticles is placed on the surface of a sample holder. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0033] [Scanning Probe Microscope] FIG. 1 is a diagram showing the configuration of a scanning probe microscope according to an embodiment of the present invention, in which a probe 100 may be in contact with a detection target 600 or may not be in contact with the detection target 600. The device is composed of at least a detection probe 100, an irradiation light source 200, a control unit 300 for controlling the position of the probe, a detection unit 400 for detecting an electric signal obtained by converting an electromagnetic wave into an electric signal by the probe, a sample holder 500 for holding the detection target, and the detection target 600. In one embodiment of the present invention, an electromagnetic wave is irradiated from the light source 200 between the probe 100 and the sample holder 500, and an evanescent wave is formed between the probe 100 and the sample holder 500. The tip of the probe 100 converts the formed evanescent wave into an electric signal, and the detection unit 400 detects the electric signal. The detection target 600 placed in the evanescent wave absorbs an electromagnetic wave of a specific wavelength, the intensity of the evanescent wave is weakened, and the evanescent wave received by the probe is weakened, so the electric signal detected by the detection unit 400 is also weakened. By sweeping the wavelength of the electromagnetic wave, the electromagnetic absorption spectrum of the target substance can be detected at the level of a single chemical bond.

[0034] The electromagnetic wave converted by the probe 100 may be a second or higher harmonic of the electromagnetic wave irradiated from the irradiation light source 200. Since the evanescent wave has high brightness, it is easy to excite second or higher harmonics. According to the present invention, the probe converts the second or higher harmonics of the incident wave into an electrical signal, and therefore the conversion can be performed without being affected by the incident wave, resulting in a high signal-to-noise ratio.

[0035] Another embodiment of the present invention is the same as the above up to the point where an evanescent wave is formed between the probe 100 and the sample holder 500 in Fig. 1, but after the detection target 600 absorbs an electromagnetic wave of a specific wavelength, it emits an electromagnetic wave of a different wavelength from the absorbed electromagnetic wave. The electromagnetic wave emitted by the probe 100 is converted into an electric signal, and the detection unit 400 detects the electric signal. With this embodiment, the electromagnetic wave emission can be detected at the level of a single chemical bond.

[0036] The wavelength of the electromagnetic wave absorbed by the detection target 600 may be the second or higher harmonic of the incident wave.

[0037] [probe] FIG. 2 illustrates one embodiment of the probe 100 of the present invention. It shows a cross section of the probe 100. The probe 100 is composed of a conductive layer 110, a photoelectric conversion layer 120, and a conductive layer 130 from the outside. The photoelectric conversion layer 120 converts electromagnetic waves near the probe into an electric signal and transmits it to the detection unit 400. The photoelectric conversion layer 120 can be composed of a semiconductor PN junction. The material of the semiconductor is not limited. Examples include simple substances such as silicon (Si) and germanium (Ge), and compound semiconductors such as CuInSe2, Cu(InGa)Se2, ZnSe, GaAs, GaN, InP, InGaAlP, InGaN, CdS, ZnSe, ZnS, SiC, and SiGe.

[0038] Of the materials constituting the photoelectric conversion layer 120, it is preferable that it is composed of at least one P-type layer selected from silicon (Si) and germanium (Ge) and at least one N-type PN junction selected from silicon (Si) and germanium (Ge).

[0039] In particular, it is desirable that the material constituting the photoelectric conversion layer 120 is composed of a PN junction of at least one P-type layer selected from copper indium selenide [CuInSe2] and copper indium gallium selenide [Cu(InGa)Se2] and at least one N-type layer selected from cadmium sulfide (CdS), zinc sulfide (ZnS), and zinc oxide (ZnO).

[0040] FIG. 3 illustrates one embodiment of the probe 100 of the present invention. It shows a cross section of the probe 100. The probe 100 is composed of a conductive layer 110, a pyroelectric layer 125, and a conductive layer 130 from the outside. The pyroelectric layer 125 converts electromagnetic waves in the vicinity of the probe into an electric signal and transmits it to the detection unit 400. The material of the pyroelectric layer is not limited. Examples include lead zirconate titanate (PZT), lead titanate (PbTiO3), barium titanate (BaTiO3), L-alanine doped deuterated triglycine sulfate (DLaTGS), cobalt phthalocyanine, lithium tantalate, polyvinyl fluoride, GaN, tourmaline, etc.

[0041] In particular, it is desirable that the material constituting the pyroelectric layer 125 is at least one material selected from lead zirconate titanate (PZT), lead titanate (PbTiO3), barium titanate (BaTiO3), and L-alanine-doped deuterated triglycine sulfate (DLaTGS).

[0042] FIG. 4 illustrates one embodiment of the probe 100 of the present invention. It shows a cross section of the probe 100. The probe 100 is composed of a conductive layer 110, a photoconductor layer 126, and a conductive layer 130 from the outside. The photoconductor layer 126 converts electromagnetic waves near the probe into an electric signal and transmits it to the detection unit 400. The material constituting the photoconductor is not limited. Examples include compounds such as cadmium sulfide (CdS), cadmium selenide (CdSe), zinc sulfide (ZnS), zinc oxide (ZnO), lead sulfide (PbS), and cadmium mercury tellurium (CdHgTe), simple elements such as selenium (Se), sulfur (S), tellurium (Te), phosphorus (P), arsenic (As), boron (B), silicon (Si), germanium (Ge), and tin (Sn), and doped semiconductors such as lithium-doped germanium.

[0043] In particular, it is desirable that the material constituting the photoconductor layer 126 be at least one material selected from cadmium sulfide (CdS), cadmium selenide (CdSe), zinc sulfide (ZnS), zinc oxide (ZnO), lead sulfide (PbS), cadmium mercury telluride (CdHgTe), selenium (Se), and lithium-doped germanium.

[0044] 5 illustrates one embodiment of a probe 100 of the present invention. It shows a cross section of the probe 100. From the outside, the probe 100 includes a conductive layer 110, a photoconductor layer, and a conductive layer 130, and the photoconductor layer includes a quantum well structure 127.

[0045] 6 illustrates one embodiment of a probe 100 of the present invention. It shows a cross section of the probe 100. From the outside, the probe 100 includes a conductive layer 110, a photoconductor layer, and a conductive layer 130, and the photoconductor layer includes a quantum dot structure 128.

[0046] 7 illustrates one embodiment of a probe 100 of the present invention. It shows a cross section of the probe 100. From the outside, the probe 100 includes a conductive layer 110, a photoconductor layer, and a conductive layer 130, and the photoconductor layer includes a type II superlattice structure 129.

[0047] 8 is a diagram showing the configuration of a scanning probe microscope according to one embodiment of the present invention, explaining a chamber 700 capable of controlling at least one of the temperature, atmosphere, and vacuum. At least the probe 100, the sample holder 500, and the detection target 600 are housed in the chamber 700, and at least one of the temperature, atmosphere, and vacuum level can be controlled. According to this embodiment, at least one of the detection requirements of the probe and the state of the detection target can be maintained in an optimal state, thereby improving detection sensitivity.

[0048] 9 shows one embodiment of a measurement example of the present invention. Electromagnetic waves may be irradiated from the back side of the sample holder 500. The shape of the sample holder is not particularly limited. Typical shapes include a trapezoid, triangular prism, semi-cylinder, and hemisphere. According to this embodiment, the influence of the incident electromagnetic waves can be eliminated by irradiating from the back side, and the detection unit 400 can perform detection with higher accuracy.

[0049] A thin film 510 of metal nanoparticles may be placed on the surface of the sample holder 500. FIG. 10 shows an example of the metal nanoparticle layer. There is no particular limitation on the metal composition of the metal nanoparticles. Common examples include gold, platinum, silver, copper, nickel, manganese, iron, zinc, and alloys thereof. There is no particular limitation on the thickness of the thin film 510. In general, it is desirable for the thickness to be in the range of 5 nanometers or more and 1000 nanometers or less. According to this embodiment, the evanescent wave is further enhanced by the metal nanoparticles, and the detection accuracy of the probe can be improved. [Industrial Applicability]

[0050] The scanning probe microscope apparatus and probe of the present invention can be used in the high-precision analytical equipment industry and in high-precision material analysis work.The scanning probe microscope apparatus of the present invention can be used to identify the type of compound, the three-dimensional structure of a compound, and the chirality of a compound, and can be applied as a new inspection method in the chemical industry, pharmaceutical industry, and inspection industry.

[0051] The present invention is not limited to the above-described embodiment, and any modifications and improvements that can achieve the object of the present invention are included in the present invention. [Explanation of symbols]

[0052] 10. Scanning Probe Microscope Device 100 Probes 110 Conductive layer 120 Photoelectric conversion layer 125 Pyroelectric layer 126 Photoconductor Layer 127 Quantum well structure photoconductor layer 128 Quantum dot structure photoconductor layer 129 type two-superlattice structure photoconductor layer 130 Conductive layer 200 light source 300 Control section 400 Detector 500 Sample holder 510 Thin Film of Metal Nanoparticles 600 detection targets 700 Chamber

Claims

1. A scanning probe microscope device comprising: a detection unit having at least one probe that is placed in contact or non-contact with an object to be detected; a control unit that controls the detection unit; a light source unit; and a signal detection unit, wherein the probe has a function of converting an electromagnetic wave signal into an electrical signal, and the probe is controlled by the control unit, and is characterized in that the object to be detected can be identified by capturing changed electromagnetic waves in the vicinity of the object to be detected, converting the electromagnetic wave signal irradiated from the light source unit into an electrical signal, and transferring it to the signal detection unit.

2. The electromagnetic wave signal in the vicinity of the detection object according to claim 1 is characterized in that it is a higher harmonic of the electromagnetic wave irradiated from the light source unit, the higher harmonic including the second harmonic.

3. In the scanning probe microscope according to claim 1, the probe having the function of converting the electromagnetic wave into an electric signal comprises, from the outside, at least a tip portion of a conductor layer, a photoelectric conversion layer and another conductor layer.

4. The photoelectric conversion layer of claim 3 is preferably composed of a PN junction of at least one P-type layer selected from silicon (Si) and germanium (Ge) and at least one N-type layer selected from silicon (Si) and germanium (Ge).

5. The photoelectric conversion layer of claim 3 is made of copper indium selenide [CuInSe ２ ], copper indium gallium selenide [Cu(InGa)Se ２ and at least one N-type layer selected from cadmium sulfide (CdS), zinc sulfide (ZnS), and zinc oxide (ZnO).

6. In the scanning probe microscope according to claim 1, the probe having the function of converting the electromagnetic wave into an electric signal comprises, from the outside, at least a tip portion of a conductive layer, a pyroelectric layer and another conductive layer.

7. The pyroelectric layer of claim 6 is made of lead zirconate titanate (PZT), lead titanate (PbTiO ３ ), barium titanate (BaTiO ３ ), L-alanine-doped deuterated triglycine sulfate (DLaTGS).

8. In the scanning probe microscope according to claim 1, the probe having the function of converting the electromagnetic wave into an electric signal comprises, from the outside, at least a tip portion of a conductive layer, a photoconductor layer and a conductive layer.

9. It is desirable that the photoconductor layer of claim 8 is composed of at least one layer selected from cadmium sulfide (CdS), cadmium selenide (CdSe), zinc sulfide (ZnS), zinc oxide (ZnO), lead sulfide (PbS), cadmium mercury tellurium (CdHgTe), selenium (Se), and lithium-doped germanium.

10. In the scanning probe microscope according to claim 8, the probe having the function of converting the electromagnetic wave into an electric signal is configured such that the photoconductor layer includes a quantum well structure.

11. In the scanning probe microscope according to claim 8, the probe having the function of converting the electromagnetic wave into an electric signal is configured such that the photoconductor layer includes a quantum dot structure.

12. In the scanning probe microscope according to claim 8, the probe having the function of converting the electromagnetic wave into an electric signal is configured such that the photoconductor layer includes a type II superlattice structure.

Images