JP3134546B2 - Probe manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a probe. This probe is mainly used for a photon scanning tunneling microscope.

[0002]

2. Description of the Related Art In recent years, non-contact, non-destructive, high-resolution microscopes have become increasingly important in a wide range of fields such as biology and semiconductor device development. Conventional optical microscopes have excellent characteristics in terms of non-contact and non-destruction, but the range of use is limited due to the limitation of resolution due to the diffraction limit due to the principle of using an imaging optical system. Was. A photon scanning tunneling microscope has been developed to solve these problems.

A photon scanning tunneling microscope (or a near-field scanning microscope) has been developed to solve these problems. A measurement method using a photon scanning tunneling microscope will be described. First, illumination light is incident from the back surface of the sample so as to satisfy the condition of total reflection on the surface of the sample. The irradiation of the illumination light generates an electric field called an evanescent wave on the sample surface. The evanescent wave decays exponentially with the distance from the surface, and becomes 1 / e at a height of about the wavelength. A high vertical resolution can be obtained by detecting this evanescent wave with a probe that scans the sample surface in a non-contact manner. In addition, by providing an opening portion smaller than the wavelength of light in the probe and limiting the area in the surface where the evanescent wave is detected, a higher lateral resolution can be obtained as compared with a conventional optical microscope. The evanescent wave decays exponentially with the distance from the sample surface as described above. Therefore, in order to obtain high resolution, a minute opening at the tip of the probe is not necessarily required, and only the tip of the probe may be sharpened.

[0004] Regarding the vertical resolution, the S / S
N and the lateral resolution are determined by the effective small aperture diameter. Therefore, it is necessary to increase the aperture diameter in order to obtain a high vertical resolution, and to reduce the aperture diameter in order to obtain a high horizontal resolution, and there is a trade-off relationship between the vertical resolution and the horizontal resolution. It can be said that there is. The required vertical and horizontal resolution is
Since it differs depending on the sample to be measured, the sharp angle of the probe tip also needs to be changed for each sample to be measured. Therefore, when manufacturing a probe, it is important how a probe having a desired sharp angle can be manufactured with high reproducibility.

[0005] The probe is manufactured by using an optical fiber composed of a quartz core doped with cladding and germanium oxide as a starting material, cutting this into an appropriate length, and sharpening the tip. As a method of sharpening, mechanical polishing (Chiang Akebono, Naoyuki Tomita, Kenichi Nakagawa, Motoichi Otsu “Optical Scanning Tunneling Microscope (Photon STM)-Analysis and Design-”, IEICE Technical Report, IM-89-45 , P.1-9, (1987)
And melt drawing (E. Betzing, M. Isaacson, A. Lewis
“Collection mode near-field scanning opticalmicro-
scopy ”, Appl.Phys.Lett., 51, (25), p.2088-2090, (19
87)).

However, these methods have problems in that the sharp angle of the tip of the probe does not become too sharp, and that the processing accuracy is low. It has been proposed to sharpen by hydrofluoric acid etchant (chemical) etching in order to produce a probe for obtaining high lateral resolution.

[0007]

As a result of repeated studies, the present inventors have found that an optical fiber consisting of a quartz core and a clad to which 3-28 mol% of germanium oxide is added is referred to as "a 50% by weight hydrofluoric acid aqueous solution: 1 Volume, water: 1 volume and concentration
40 wt% ammonium fluoride aqueous solution: Y volume part (Y =
It has been proposed to manufacture a probe by etching with an etching solution consisting of 6 to 10) and changing the component ratio of the etching solution to sharpen the tip of the optical fiber (Japanese Patent Application No. 4-39755). According to the proposed manufacturing method, it is possible to control the sharp angle of the probe tip only by changing the component ratio of the etching solution without changing the concentration of germanium oxide added to the core. Has a radius of curvature of 5 nm or less and a sharp angle of 25 degrees or less. As shown in FIG. 2B, the shape of the probe tip manufactured using this manufacturing method is such that only the center of the etched probe tip is sharpened, a protrusion is formed, and a flat portion is formed around the protrusion. Although there is an end face, the shape of the tip of the probe used in the photon scanning tunneling microscope is ideally a shape having no end face as shown in FIG.

[0010] As a result of observing a sample with a photon scanning tunneling microscope using a probe having a shape as shown in FIG. However, when the sample is slightly inclined relative to the sample surface, it is difficult to observe the details of the sample, resulting in a problem that the resolution is reduced. Further, when the sample is observed, there is a problem that the probe is significantly damaged and cannot be observed for a long time.

The present inventors have repeated observations using samples having various types and various shapes. As a result, when observing a sample having severe irregularities, the end surface is present around the protrusion at the tip of the probe. It was found that the probe tip could not approach the bottom of the sample, making it difficult to observe the details of the sample and lowering the resolution. Further, it has been found that the cause of the breakage of the probe and the inability to observe for a long time is that the end face around the protrusion at the tip of the probe collides with the sample.

Therefore, the inventors of the present invention have conducted the mechanical polishing shown in FIG.
A probe having an ideal probe tip as shown in FIG. However, when manufacturing by mechanical polishing, there are problems that the radius of curvature of the probe tip cannot be reduced, the sharp angle does not become acute, the reproducibility of the projection shape is poor, and the polished surface shape becomes rough. Was.

[0011]

Accordingly, the present inventors have conducted intensive studies and prepared an optical fiber in which the type, amount and position of the additive to the optical fiber as the raw material were varied in various ways. Etching was performed with an etching solution having various component ratios. As a result, by utilizing the fact that the etching rate by hydrofluoric acid changes depending on the composition of the optical fiber, a probe having an ideal probe tip (FIG. 2A) can be manufactured only by chemical etching without using other methods such as mechanical polishing. They have found what they can do and accomplished the present invention.

Therefore, the present invention firstly provides "3-28 mol%
A quartz core to which germanium oxide is added, a clad A which is located inside a boundary located at a radius of 0.3 to 0.6 when a radius of the optical fiber is 1, and a clad B which is located outside the boundary. 0.5 ~
The above-mentioned optical fiber to which 10 mol% of phosphorus oxide was added was treated with “a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water:
Ammonium fluoride aqueous solution of 1 volume part and concentration of 40% by weight: etching solution consisting of Y volume part (Y = 4 to 15) "
And a method of manufacturing a probe (claim 1).

Second, "" a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, an aqueous solution of ammonium fluoride having a concentration of 40% by weight: Y ₁ part by volume (Y ₁ = 1 to 3) A method for manufacturing a probe according to claim 1 (claim 2), wherein a pre-etching step of etching with an etching solution is added. Third, "3 ~
A quartz core doped with 28 mol% of germanium oxide;
Assuming that the radius of the optical fiber is 1, the radius is 0.3 to 0.1.
6 and a clad B outside the boundary and a clad B outside the boundary.
The above-mentioned optical fiber in which 5 to 30 mol% of boron oxide is added to the solution is referred to as "a 50% by weight aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, a 40% by weight aqueous solution of ammonium fluoride: Y part by volume Y = 10 to 15).

Fourthly, "a quartz core to which 3-28 mol% of germanium oxide is added, a clad A which is located inside a boundary located at a radius of 0.3-0.6 when a radius of the optical fiber is 1, and Cladding B on the outside
The optical fiber in which 5 to 15 mol% of boron oxide is added to the clad A is prepared as follows: "a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, and a concentration of 4 parts by weight.
0 wt% ammonium fluoride aqueous solution: Y volume part (Y =
A method for producing a probe (claim 4), characterized in that etching is performed with an etching solution comprising (1) to (4).

[0015] Fifth, "" 50% strength by weight aqueous solution of hydrofluoric acid: 1 part by volume of water: 1 part by volume concentration of 40 wt% ammonium fluoride aqueous solution: Y ₂ parts by volume (Y ₂ = between 1:10
In the step of etching with the "etchant comprising 5)",
A method of manufacturing a probe, characterized by adding the step of claim 4 as a pre-etching step (claim 5) ".

Sixth, "a quartz core to which 3-28 mol% of germanium oxide is added, a cladding A which is located inside a boundary located at a radius of 0.3-0.6 when a radius of the optical fiber is 1, and Cladding B on the outside
The optical fiber in which 0.5 to 10 mol% of arsenic oxide is added to the cladding B is prepared as follows: "50 parts by weight of hydrofluoric acid aqueous solution: 1 part by volume, water: 1 part by volume, concentration of 4 parts by weight"
0 wt% ammonium fluoride aqueous solution: Y volume part (Y =
And a method of manufacturing a probe characterized by performing etching with an etching solution comprising (4) to (15)).

Seventhly, "From a 50% by weight aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, an aqueous solution of ammonium fluoride having a concentration of 40% by weight: Y ₁ part by volume (Y ₁ = 1 to 2) A method for manufacturing a probe according to claim 6 (claim 7), wherein a pre-etching step of etching with an "etching solution" is added. Eighth, "3-2
A quartz core to which 8 mol% of germanium oxide is added, and a radius of 0.3 to 0.6 when the radius of the optical fiber is 1.
The optical fiber is composed of a clad A which is located inside the boundary located at the boundary and a cladding B which is located outside the boundary, and wherein the cladding B is added with 1 to 5 mol% of silicon fluoride. 1 part by volume, water: 1 part by volume, an aqueous solution of ammonium fluoride having a concentration of 40% by weight: an etching solution consisting of Y parts by volume (Y = 4 to 15) ". 8) ”.

Ninth, "from a 50% by weight aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, an aqueous solution of ammonium fluoride having a concentration of 40% by weight: Y ₁ part by volume (Y ₁ = 1 to 3) A method of manufacturing a probe according to claim 8 (claim 9), wherein a pre-etching step of etching with an etching solution is added. Tenthly, there is provided a "probe manufacturing method according to claims 1 to 9, wherein the sharpness angle of the probe is changed by changing the component ratio of the etching solution (claim 10)".

Eleventh, "light irradiating means for irradiating the inspection area, probe for detecting an electric field generated in the area, scanning means for scanning the probe, position control means for the scanning means, detection detected by the probe 2. A photon scanning tunneling microscope comprising: detecting means for converting a converted electric field into an electric signal; and image display means for displaying an image based on information from the detecting means and position information from the position control means. 10. A photon scanning tunneling microscope (claim 11), which is a probe manufactured by the method described in (10) to (10).

[0020]

In general, glass can be etched with a hydrofluoric acid buffer solution, but the etching rate varies depending on the composition of the glass and the composition of the etching solution, so that the etching rate can be controlled using this. The optical fiber as a starting material used in the present invention has a triple structure (core (1), clad A (2), clad B (3)) (a in FIG. 1). The core (1) made of quartz contains 3 to 28% of germanium oxide and has a slightly higher refractive index.

A clad A (2) located at the outer periphery of the core (1) and adjacent to the core (1), and a clad B (3) located at the outer periphery of the clad A (2) and adjacent to the clad A (2). )
Are formed. Clad A (2) and Clad B
When the radius of the optical fiber is 1, the boundary of (3) is
The composition of each clad is changed so that it exists in the range of 30 to 60% in the radial direction from the center of the core (1).

As a substance to be added to the cladding A (2), 5 to 15 mol% of boron oxide can be mentioned. Materials added to the cladding B (3) include 0.5 to 10 mol% of phosphorus oxide, 5 to 30 mol% of boron oxide, and 0.5 to 10 mol%.
Arsenic oxide. When a substance is added to the cladding A (2), nothing is added to the cladding B (3), and the composition is only quartz as a raw material. Similarly, when a substance is added to the clad B (3), nothing is added to the clad A (2). In each case, the content of germanium oxide added to the quartz core (1) is 3 to 28 mol%.

In chemical etching, a 50% by weight hydrofluoric acid aqueous solution: 1 part by volume, water: 1 part by volume, and a concentration of 40%
Aqueous solution of ammonium fluoride in weight%: use an etching solution composed of Y capacity parts (change Y). The composition of this etchant is clad A (2) and clad B (3)
Is adjusted so that the etching rate is higher in the clad B (3) than in the clad A (2) due to the difference in the composition of the clad B (3).

In the chemical etching, Y in the etching solution is used.
(Amount of ammonium fluoride aqueous solution having a concentration of 40% by weight) may be repeated twice. The reason for repeating the etching in this way is that the etching rate of the core (1) is
This is because, since germanium oxide is added, the etching rate is the slowest and the center of the probe end face is sharpened, but the sharpness is insufficient. Sufficient sharpness can be obtained by repeating the etching.

Further, by adjusting the component ratio of the etching solution in the etching in the second stage, it is possible to control the size of the sharpened angle after the sharpening.

[0026]

Embodiment 1 An optical fiber used in the present embodiment comprises a quartz core and a clad. The clad is clad A (2)
And the cladding B (3), and the boundary between the cladding A (2) and the cladding B (3) is 50% radially from the center of the core when the radius of the optical fiber is 1. 5 mol% of phosphorus oxide is added to (3). The core (1) contains germanium oxide at a concentration of 23 mol%.
Added. The optical fiber (1) is cut perpendicularly to the optical axis by cracking (FIG. 3A).

As an etching solution, a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, and a concentration of 40% by weight
Ammonium fluoride aqueous solution: 2 parts by volume (hereinafter referred to as etching solution A) and a 50% by weight hydrofluoric acid aqueous solution: 1
A volume part, water: one volume part, an aqueous solution of ammonium fluoride having a concentration of 40% by weight: 10 volume parts (hereinafter referred to as an etching solution B) are prepared. These were mixed in a Teflon beaker to prepare various etching solutions. This is put into the etching solution A up to a position 1 mm from the tip of the optical fiber, immersed for 50 to 60 minutes without stirring, and allowed to stand.

At the tip of the optical fiber, the center of the end face becomes sharp and the periphery thereof becomes tapered (FIG. 3B). However, in this state, the probe at the tip of the probe is insufficient in point such as a sharp angle. Therefore, the probe in this state is brought into contact with the etching solution B only at the end face, immersed for 120 minutes without stirring, and allowed to stand. As a result, FIG.
A probe having a probe tip having the following shape and a sharp angle of about 25 degrees was obtained.

[0029]

Embodiment 2 When the radius of the optical fiber is 1 at the boundary between the clad A (2) and the clad B (3), the clad B is positioned 50% radially from the center of the core.
20 mol% of boron oxide is added to (3). Germanium oxide is added to the core (1) at a concentration of 23 mol%. The optical fiber is cut perpendicular to the optical axis by cracking.

As an etching solution, a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, a concentration of 40% by weight
Ammonium fluoride aqueous solution: Prepare 15 parts by volume. The above-mentioned optical fiber is placed in an etching solution up to a position 1 mm from the tip, and immersed for 100 to 120 minutes without stirring to perform etching. At the tip of the optical fiber, the center of the end face is sharpened and the periphery is tapered. As a result, a probe having a tip angle of about 20 degrees was obtained.

[0031]

Embodiment 3 When the boundary between the clad A (2) and the clad B (3) is assumed to be 1 in the radius of the optical fiber, the clad A is positioned 50% radially from the center of the core.
(2) 10 mol% of boron oxide is added. Germanium oxide at a concentration of 23 mol% is added to the core (1). The optical fiber is cut perpendicular to the optical axis by cracking.

As an etching solution, a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, a concentration of 40% by weight
Ammonium fluoride aqueous solution: 2 parts by volume are prepared.
(Hereinafter referred to as etching solution A) and a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, and a concentration of 40% by weight
Ammonium fluoride aqueous solution: 10 parts by volume (hereinafter referred to as etching solution B) is prepared.

The above-mentioned optical fiber is placed in an etching solution A up to a position 1 mm from the tip, and immersed for 50 to 60 minutes without stirring to perform etching. At the tip of the optical fiber, the center of the end face becomes sharp and the periphery thereof becomes tapered. However, in this state, the probe at the tip of the probe is insufficient in point such as a sharp angle. Therefore, the probe in this state is brought into contact with the etching solution B only at the end face, immersed for 120 minutes without stirring, and allowed to stand.

As a result, it was possible to obtain a probe having a tip angle of about 25 degrees.

[0035]

Embodiment 4 When the radius of the optical fiber is set to 1 at the boundary between the clad A (2) and the clad B (3), the clad A (2) is positioned 50% radially from the center of the core.
Has 5 mol% of arsenic oxide added thereto. Germanium oxide is added to the core (1) at a concentration of 23 mol%. The optical fiber is cut perpendicular to the optical axis by cracking.

As an etchant, a 50% by weight aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, a concentration of 40% by weight
Ammonium fluoride aqueous solution: 2 parts by volume are prepared.
(Hereinafter referred to as etching solution A) and a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, and a concentration of 40% by weight
Ammonium fluoride aqueous solution: 10 parts by volume (hereinafter referred to as etching solution B) is prepared.

The above-mentioned optical fiber is put into an etching solution A up to a position 1 mm from the tip, and immersed for 50 to 60 minutes without stirring to perform etching. At the tip of the optical fiber, the center of the end face becomes sharp and the periphery thereof becomes tapered. However, in this state, the probe at the tip of the probe is insufficient in point such as a sharp angle. Therefore, the probe in this state is brought into contact with the etching solution B only at the end face, immersed for 120 minutes without stirring, and allowed to stand.

As a result, a probe having a tip angle of about 25 degrees was obtained. Further, if the manufacturing method of the present invention is applied, the control of the focal length in manufacturing the microlens at the tip of the optical fiber becomes easy. Further, the processing of the tip of the optical fiber having an arbitrary curvature becomes easy.

[0039]

According to the present invention, a probe having an ideal shape as shown in FIG. 2A can be manufactured with good reproducibility only by chemical etching (without using another method such as mechanical polishing). it can. Therefore, the resolution when observing a sample with severe irregularities is increased. In addition, since the probe does not collide with the sample, long-term observation is possible.

[Brief description of the drawings]

1A is a vertical cross-sectional view of an optical fiber according to the present invention cut perpendicularly to an optical axis, and FIG. 1B is a cross-sectional view of the probe tip after etching parallel to the optical axis. It is sectional drawing.

2A is a cross-sectional view of a probe for a photon scanning tunneling microscope having an ideal shape, and FIG. 2B is a cross-sectional view of a conventional probe.

FIG. 3 is a schematic diagram showing a change in the shape of a probe tip accompanying an etching process according to one embodiment of the present invention.

[Explanation of symbols]

 1 ... core 2 ... clad A 3 ... clad B

Continuation of the front page (56) References JP-A-6-3595 (JP, A) JP-A-6-117840 (JP, A) JP-A-6-74899 (JP, A) JP-A-3-91710 (JP) , A) Shudong Jiang, His ao Ohsawa, Kazunobu Yamada, Togar Pang aribuan, Motoichi O htsu, Kensaku Imai, and Atsushi Ikai, "Nanometric Scale B iosample Observati on Using a Photon Scannig Tunneling Microscope", Japane se Journal of Appl ied Physics Vol. 31, Part 1, No. 7, p. 2282-2287 Togar Pangaribua n, Kazunobu Yamada, Shudong Jiang, Hisa o Ohsawa and Motoi chi Ohtsu, "Reprodu cible Fabrication Technique of Nanom etric Tip Diameter Fiber Probe for P hoton Scanning Tun neling Microscop e", Japanese Journa l of Applied Physics, 1992, Vol. 31, Part 2, No. 9A, p. L1302-L1304 (58) Fields investigated (Int. Cl. ⁷ , DB name) G01N 13/10-13/24 G12B 21/06 H01J 37/28 G01B 11/30 JICST file (JOIS)

Claims (11)

(57) [Claims] 1. A quartz core to which 3-28 mol% of germanium oxide is added, a cladding A inside a boundary located at a radius of 0.3-0.6 when an optical fiber has a radius of 1, and a cladding A outside the boundary. The optical fiber, which is composed of a clad B corresponding to the above, and in which 0.5 to 10 mol% of phosphorus oxide is added to the clad B, has a concentration of 50% by weight.
Aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, aqueous solution of ammonium fluoride having a concentration of 40% by weight: Y part by volume (Y = 4 to
15) A method for producing a probe, characterized by performing etching with an etching solution comprising (15). 2. Etching comprising a 50% by weight aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, an aqueous solution of ammonium fluoride at a concentration of 40% by weight: Y ₁ part by volume (Y ₁ = 1 to 3). 2. The method for manufacturing a probe according to claim 1, further comprising a preliminary etching step of etching with a "liquid". 3. A quartz core to which 3 to 28 mol% of germanium oxide is added, a clad A which is located inside a boundary located at a radius of 0.3 to 0.6 when an optical fiber has a radius of 1, and a cladding A which is located outside the boundary. The optical fiber, comprising a clad B having a concentration of 50% by weight, an aqueous solution of hydrofluoric acid having a concentration of 50% by weight, a volume of water being 1 part by volume, and a concentration of 40% by weight. Ammonium fluoride aqueous solution: Y volume part (Y = 10
15) A method for producing a probe, characterized by performing etching with an etching solution comprising (15). 4. A quartz core to which 3 to 28 mol% of germanium oxide is added, a clad A which is located inside a boundary located at a radius of 0.3 to 0.6 when an optical fiber has a radius of 1, and a cladding A which is located outside the boundary. The optical fiber, which is composed of a clad B and has a clad A to which 5 to 15 mol% of boron oxide is added, has a concentration of 50% by weight.
Aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, aqueous solution of ammonium fluoride having a concentration of 40% by weight: Y part by volume (Y = 1 to
A method for producing a probe, characterized in that the etching is performed with an etching solution comprising (4). 5. An etching process comprising: a 50% by weight aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, an aqueous solution of ammonium fluoride at a concentration of 40% by weight: Y ₂ parts by volume (Y ₂ = 10 to 15). A method for manufacturing a probe, characterized by adding the step of claim 4 as a preliminary etching step to the step of etching with a "liquid". 6. A quartz core to which 3-28 mol% of germanium oxide is added, a clad A which is located inside a boundary located at a radius of 0.3-0.6 when a radius of the optical fiber is 1, and a clad A which is located outside the boundary. The optical fiber, comprising a clad B having a concentration of 50% by weight, wherein the clad B is added with 0.5 to 10 mol% of arsenic oxide.
Aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, aqueous solution of ammonium fluoride having a concentration of 40% by weight: Y part by volume (Y = 4 to
15) A method for producing a probe, characterized by performing etching with an etching solution comprising (15). 7. Etching consisting of a 50% by weight aqueous solution of hydrofluoric acid: 1 part by volume, water: 1 part by volume, an aqueous solution of ammonium fluoride at a concentration of 40% by weight: Y ₁ part by volume (Y ₁ = 1 to 2). 7. The method for manufacturing a probe according to claim 6, further comprising a preliminary etching step of etching with a "liquid". 8. A quartz core to which 3-28 mol% of germanium oxide is added, a clad A which is located inside a boundary located at a radius of 0.3-0.6 when a radius of the optical fiber is 1, and a cladding A which is located outside the boundary. The optical fiber having a cladding B corresponding to 1 to 5 mol% silicon fluoride added to the cladding B is referred to as "a hydrofluoric acid aqueous solution having a concentration of 50% by weight: 1 part by volume, water: 1 part by volume, and a concentration of 40% by weight." Ammonium fluoride aqueous solution: Y volume part (Y = 4-1)
5) A method for producing a probe, characterized by etching with an etching solution comprising 5). 9. Etching consisting of ₁ part by volume of a 50% by weight aqueous solution of hydrofluoric acid, 1 part by volume of water, and an aqueous solution of ammonium fluoride having a concentration of 40% by weight: Y ₁ part by volume (Y ₁ = 1 to 3). 9. The method for manufacturing a probe according to claim 8, further comprising a preliminary etching step of etching with a "liquid". 10. The method for manufacturing a probe according to claim 1, wherein a sharp angle of the probe is changed by changing a component ratio of the etching solution. 11. A light irradiation means for irradiating an inspection area, a probe for detecting an electric field generated in the area, a scanning means for scanning the probe, a position control means for the scanning means,
In a photon scanning tunneling microscope, comprising: a detection unit that converts an electric field detected by the probe into an electric signal, an image display unit that displays an image based on information from the detection unit and position information from the position control unit, A photon scanning tunneling microscope, wherein the probe is a probe manufactured by the method according to claim 1.