Near-field exposure apparatus and probe for generating near-field

Abstract

To provide a method and an apparatus for forming a semiconductor pattern with a resolution of 1 nanometer order using a conventional resist material and an inexpensive apparatus.SOLUTION: An exposure apparatus according to the present invention includes a focusing unit having at least one probe that is placed in contact or non-contact with an object to be exposed, a control unit that controls the focusing unit, and a light source unit, and the probe has a function of focusing an electromagnetic signal at its tip, and the probe is controlled by the control unit, and focuses the electromagnetic signal irradiated with from the light source unit in the vicinity of the object to be detected, thereby enabling exposure of the object.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method and an apparatus for converting an electromagnetic wave irradiated from a light source into near-field light and forming a pattern using the near-field light and / or second- or higher-harmonic waves including the second harmonic of the irradiated light. [Background technology]

[0002] In the semiconductor industry, extreme ultraviolet lithography is used to form patterns of 7 nanometers or less. Known technology uses extreme ultraviolet light with a wavelength of 13.5 nanometers as a light source. This technology requires large equipment and a dedicated mask, so there is a demand for equipment that is cheaper and can use conventional resist materials. For this reason, attempts are being made to develop pattern formation methods that apply near-field light. Patent document 1 and non-patent document 1 describe the near-field light pattern formation method. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3859991: Pattern formation method using near-field light and its device

[0004] [Non-Patent Document 1] International Journal of Extreme Manufacturing(USA),2021,Vol.3,Article No.:0320002,Sub-10 nm fabrication: methods and application Summary of the Invention [Problem to be solved by the invention]

[0005] Even with the techniques of Patent Document 1 and Non-Patent Document 1, it has not been possible to form a semiconductor pattern with a resolution on the order of 1 nanometer using conventional resist materials and inexpensive equipment.

[0006] The present invention has been made in view of the above, and its object is to provide a method and apparatus for forming a semiconductor pattern with a resolution on the order of 1 nanometer using conventional resist materials and inexpensive equipment. [Means for solving the problem]

[0007] (1) The present invention is a near-field exposure apparatus comprising a focusing unit having at least one probe placed in contact or non-contact with an exposure object, a control unit for controlling the focusing unit, and a light source unit, wherein the probe has a function of focusing an electromagnetic wave signal at its tip, and the probe is controlled by the control unit to focus the electromagnetic wave signal irradiated from the light source unit near the exposure object, thereby enabling exposure of the object.

[0008] (2) A probe that focuses the electromagnetic signal of (1) at its tip is characterized in that the electromagnetic signal irradiated from the light source is converted into a higher-order harmonic, including the second order, by a near field, and exposure is performed with the higher-order harmonic, including the second order, of the irradiated electromagnetic signal.

[0009] (3) In the exposure apparatus of (1) and (2), a probe having a function of focusing the electromagnetic wave at a tip portion is characterized in that a local evanescent wave is formed at the tip portion, and by moving the probe in the vertical and horizontal directions, one or more of the spot diameter and exposure time of the evanescent light acting on the exposure object can be controlled.

[0010] (4) In the exposure apparatus of (1), the probe having the function of concentrating the electromagnetic waves at a tip is characterized in that it has metal nanocrystal particles at the tip.

[0011] (5) It is desirable that the maximum dimension of the metal nanocrystal particle attached to the tip of the probe (4) is 0.5 nanometers (nm) or more and 500 nanometers or less.

[0012] (6) It is desirable that the metal crystal nanoparticles attached to the tip of the probe (4) are composed of at least one metal selected from palladium (Pd), platinum (Pt), gold (Au), silver (Ag), copper (Cu), nickel (Ni), zinc (Zn), and stainless steel, or an alloy.

[0013] (7) In the exposure apparatus of (1), the probe having the function of focusing the electromagnetic wave signal at a tip is configured to convert at least a portion of the electromagnetic wave signal into an electrical signal, transmit the electrical signal to an electrical signal detection unit, and identify the composition of the object to be exposed.

[0014] (8) In the exposure apparatus of (1), the probe having the function of focusing the electromagnetic wave signal at a tip is configured to scatter at least a portion of the electromagnetic wave signal and transmit it to an electromagnetic signal detection unit, thereby enabling the composition of the exposed object to be identified. Effect of the Invention

[0015] According to the present invention, in an exposure device, a probe having a function of concentrating the electromagnetic wave at its tip forms a local evanescent wave at its tip, and by moving the probe in the vertical and horizontal directions, the intensity of the evanescent wave at the probe tip is inversely proportional to the exponential function of the distance between the probe and the exposure target, making it possible to control one or more of the spot diameter and exposure time, and to perform exposure with a resolution of 1 nanometer. On the other hand, when a known exposure device is used, it is not possible to perform exposure with a resolution of 1 nanometer.

[0016] Furthermore, according to the present invention, a probe having a function of focusing the electromagnetic wave signal at its tip detects at least a portion of the electromagnetic wave signal, making it possible to determine that the compound components directly below the probe are changed by exposure to light, and thus making it possible to judge the exposure conditions on the spot. [Brief description of the drawings]

[0017] [Figure 1] 1 is a diagram showing a configuration of a near-field exposure apparatus according to an embodiment of the present invention.

[0018] [Diagram 2] FIG. 2 is a diagram showing the configuration of a probe for a near-field exposure mirror apparatus according to one embodiment of the present invention, and shows one structure in which metal nanocrystal particles are provided at the tip of the probe.

[0019] [Diagram 3] FIG. 2 is a diagram showing the configuration of a probe for a near-field exposure mirror apparatus according to one embodiment of the present invention, showing one structure in which a plurality of metal nanocrystal particles are provided at the probe tip.

[0020] [Figure 4] FIG. 2 is a diagram showing the configuration of a near-field exposure apparatus according to one embodiment of the present invention, illustrating a structure in which a portion of the evanescent wave directly below the probe tip is scattered to the outside so that the scattered light can reach an external photodetector. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0022] [Near-field exposure device] FIG. 1 is a diagram showing the configuration of a near-field exposure apparatus according to an embodiment of the present invention, in which a probe 1 may be in contact with an exposure target 10 or may not be in contact with the exposure target 10. The apparatus is composed of at least a probe 1 for focusing light, a stage 2 for fixing the target 1, a light source 3 for irradiation, a focusing optical system 4, a light source control unit 5 for controlling the light source, and a probe fixing unit 6. If necessary, it is preferable that the apparatus is composed of a probe actuator 7 for moving the position of the probe 1, a control unit 8 for controlling the actuator, and a stage control unit 9 for changing the positions of the exposure target 10 and the substrate 11. In one embodiment of the present invention, an electromagnetic wave is irradiated from a light source 3 to the tip of the probe 1, and an evanescent wave is formed between the probe 1 and the exposure target 10. The intensity of the evanescent wave formed at the tip of the probe 1 attenuates exponentially as the distance from the tip of the probe 1 increases, and the spot diameter of the evanescent wave decreases. Therefore, by controlling the distance between the probe 1 and the exposure object, the intensity of the evanescent wave irradiated onto the exposure object can be controlled, and the spot diameter of the evanescent wave can also be controlled.By controlling the position of the probe 1 and / or the position of the stage 2, the exposure object can be exposed as designed.The spot diameter of the evanescent wave can be controlled with a resolution of 1 nanometer, and a 1 nanometer pattern can be engraved.

[0023] Since the evanescent wave has high brightness, it excites second and higher harmonics including the second order. According to one embodiment of the present invention, the probe 1 generates second and higher harmonics including the second order of the incident wave. Since the second and higher harmonics including the second order expose the exposure target and the incident wave does not affect the exposure target, it is possible to provide an irradiation method with less noise and to engrave a 1-nanometer pattern.

[0024] [probe] FIG. 2 is a diagram showing the configuration of a probe 1 constituting a near-field exposure apparatus according to one embodiment of the present invention, and the probe 1 has a metal nanocrystalline particle 101 at its tip.

[0025] FIG. 3 is a diagram showing the configuration of a probe 1 constituting a near-field exposure apparatus according to one embodiment of the present invention, and the probe 1 has a plurality of metallic nanocrystal particles 101, 102, 103, and 105 at its tip.

[0026] The material of the probe 1 is not limited. Metals, alloys, semiconductors, insulators, etc. can be used. Specifically, platinum (Pt), tungsten (W), gold (Au), silver (Ag), copper (Cu), zinc (Zn), nickel (Ni), titanium (Ti), platinum-iridium alloy (Pt-Ir), brass, cupro-nickel, stainless steel, silicon (Si), germanium (Ge), copper indium gallium selenide [Cu(InGa)Se↓2], diamond, graphite, etc. are preferably used. A local surface evanescent wave is excited around the tip of the probe made of the above materials, and the light intensity is enhanced by about 1000 times. By controlling the position of the probe 1 and / or the position of the stage 2, the exposure target can be exposed as designed. The spot diameter of the evanescent wave can be controlled with a resolution of 1 nanometer, and a pattern of 1 nanometer can be engraved.

[0027] The size of the metal nanocrystal particles for forming the evanescent light spot mentioned above is preferably such that the dimension of the longest part of the crystal is 0.5 nanometers or more and 500 nanometers or less. With this size, stronger evanescent waves can be formed around the periphery when light is irradiated to the edge of the nanometal crystal. This improves the efficiency of exposure. Also, even if multiple metal nanocrystals are formed near the tip of the probe 1, the evanescent waves around the metal nanocrystals that are far away from the exposure object do not reach the exposure object, so this does not interfere with exposure. Therefore, only the evanescent waves from the edge of the metal nanocrystal that is closest to the exposure object expose the exposure object.

[0028] [Probe tip light detection method] FIG4 is a diagram showing the configuration of a near-field exposure apparatus according to one embodiment of the present invention, and shows a structure in which a part of the evanescent wave just below the tip of the probe is scattered to the outside, and the scattered light can reach an external photodetector. Since the chemical composition of an exposure object exposed to the evanescent wave at the tip of the probe changes, the absorption spectrum of the evanescent wave at the tip of the probe 1 changes before and after exposure. By scattering a part of the evanescent wave just below the tip of the probe 1 to the outside and allowing the scattered light to reach an external photodetector, the spectral change of the exposure object can be detected.

[0029] A part of the evanescent light directly below the tip of the probe can be converted into an electrical signal by a probe equipped with a photoelectric conversion function (not shown).

[0030] The exposure apparatus, the manufacturing method and the use method of the probe, which are the embodiments of the present invention, are not limited to the above-mentioned embodiment, and can be variously modified and implemented within the scope of the technical concept of the present invention. Specific examples of the present embodiment are shown in the following examples. However, the present invention is not limited to these examples. EXAMPLES

[0031] (Test Example 1) Deposition of gold nanocrystal particles on the probe tip: A silicon (Si) atomic force microscope (AFM) probe was washed with ethanol for 2 minutes. The washed probe tip was immersed in a 0.76 mol / L ammonium fluoride (NH↓4F) solution for 120 seconds to hydrogen-terminate the silicon surface. The treated probe tip was immersed in the following gold electroless plating solution at a temperature of 25°C for 1 minute to deposit gold nanoparticle crystals of 10 nanometer size on the probe tip. Composition of gold electroless plating solution: 5 mmol / L sodium chloroaurate (NaAuCl↓4), 25 mmol / L ammonium chloride (NH↓4Cl), 25 mmol / L sodium thiosulfate (Na↓2S↓2O↓3), 75 mmol / L sodium sulfite (Na↓2SO↓3), 2 wt% hydrofluoric acid (HF).

[0032] (Test Example 2) Precipitation of palladium (Pd) nanocrystal particles on the probe tip: The use, cleaning, and surface hydrogen termination of a silicon probe were the same as in Test Example 1. The treated probe tip was immersed in the following palladium (Pd) electroless plating solution at 25°C for 2 minutes to precipitate palladium (Pd) nanoparticle crystals of 5 nanometer size on the probe tip. Composition of palladium (Pd) electroless plating solution: 0.25 mmol / L palladium chloride (PdCl↓2), 14 mmol / L hydrochloric acid (HCl), 280 mmol / L hydrofluoric acid (HF), and 760 mmol / L ammonium fluoride (NH↓4F).

[0033] (Test Example 3) Precipitation of palladium (Pd) / platinum (Pt) nanocrystalline particles on the probe tip: The process up to the precipitation of palladium (Pd) nanocrystalline particles was the same as in Example 2. The probe tip on which the palladium (Pd) nanocrystalline particles were precipitated was immersed in the platinum (Pt) electroless plating solution below at 60° C. for 1 minute to precipitate platinum (Pt) nanocrystalline particles of 30 nanometers in size. Composition of the platinum (Pt) electroless plating solution: 10 mmol / L chloroplatinic acid (H↓2PtCl↓6), 300 mmol / L ammonia (NH↓3), 40 mmol / L hydrazine (N↓2H↓4).

[0034] (Test Example 4) Precipitation of palladium (Pd) / silver (Ag) nanocrystalline particles on the probe tip: The precipitation of palladium (Pd) nanocrystalline particles was the same as in Example 2. The probe tip on which the palladium (Pd) nanocrystals were precipitated was immersed in the following silver (Ag) electroless plating solution at 25°C for 1 minute to precipitate silver (Ag) nanocrystalline particles of 25 nanometers in size. Composition of the silver (Ag) electroless plating solution: 0.5 mmol / L silver nitrate (AgNO↓3), 300 mmol / L ammonia (NH↓3), 40 mmol / L hydrazine (N↓2H↓4).

[0035] (Test Example 5) Precipitation of palladium (Pd) / copper (Cu) nanocrystalline particles on the probe tip: The precipitation of palladium (Pd) nanocrystalline particles was the same as in Example 2. The probe tip on which the palladium (Pd) nanocrystals were precipitated was immersed in the following copper (Cu) electroless plating solution at 25°C for 1 minute to precipitate copper (Cu) nanocrystalline particles of 20 nanometers in size. Composition of the copper (Cu) electroless plating solution: 0.5 mmol / L copper sulfate (CuSO↓4), 300 mmol / L EDTA (EDTA), 400 mmol / L thioglycolic acid.

[0036] (Test Example 6) Precipitation of palladium (Pd) / nickel (Ni) nanocrystalline particles on the probe tip: The precipitation of palladium (Pd) nanocrystalline particles was the same as in Example 2. The probe tip on which the palladium (Pd) nanocrystalline particles were precipitated was immersed in the following nickel (Ni) electroless plating solution at 60°C for 1 minute to precipitate nickel (Ni) nanocrystalline particles of 20 nanometers in size. Composition of nickel (Ni) electroless plating solution: 0.5 mmol / L nickel sulfate (NiSO4), 300 mmol / L EDTA (EDTA), 400 mmol / L sodium hypophosphite (NaH2PO2).

[0037] All of the above-mentioned probes having nanocrystal particles precipitated at their tips were effective in forming evanescent waves at the tips of the probes, and could be used in the exposure apparatus of the present invention. [Industrial Applicability]

[0038] The near-field exposure apparatus and probe of the present invention can be used in the exposure process of the semiconductor industry.The near-field exposure apparatus of the present invention is inexpensive, and can use conventional visible light or near-infrared light sources and conventional photoresist materials, and can expose and draw patterns with a line width / space resolution of 1 nanometer.

[0039] 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]

[0040] 1 Probe 2 Stage 3 light source 4. Light collecting optical system 5 Light source control system 6 Probe fixing part 7 Probe actuator 8 Probe control section 9 Stage Control Unit 10 Exposure object 11 Substrate 15 Scattered light 17 Light detection section 18 Spectral Calculation Section 101 Metal nanocrystal particles at the tip of the probe 102 Metal nanocrystal particles attached to positions other than the probe tip 103 Metal nanocrystal particles attached to positions other than the probe tip 105 Metal nanocrystal particles attached to the probe tip and other positions

Claims

1. A near-field exposure apparatus comprising: a focusing unit having at least one probe arranged in contact or non-contact with an exposure object; a control unit for controlling the focusing unit; and a light source unit, wherein the probe has a function of focusing an electromagnetic wave signal at its tip, and the probe is controlled by the control unit and focuses the electromagnetic wave signal irradiated from the light source unit near the exposure object, enabling exposure of the object.

2. The probe for focusing an electromagnetic wave signal at a tip of claim 1 is characterized in that the electromagnetic wave signal irradiated from the light source unit is converted into a higher-order harmonic of second order or higher, including the second order, by a near field, and exposure is performed with the higher-order harmonic of the irradiated electromagnetic signal, including the second order or higher.

3. In the exposure apparatus of claims 1 and 2, the probe having the function of concentrating the electromagnetic wave at its tip forms a local evanescent wave at the tip, and by moving the probe in the vertical and horizontal directions, it is possible to control one or more of the spot diameter and exposure time of the evanescent wave acting on the exposure object.

4. 2. The exposure apparatus according to claim 1, wherein the probe having the function of concentrating the electromagnetic wave at a tip portion has metal nanocrystal particles at the tip portion.

5. It is preferable that the maximum dimension of the metal nanocrystal particle provided at the tip of the probe of claim 4 is 0.5 nanometers (nm) or more and 500 nanometers or less.

6. It is desirable that the metal crystal nanoparticles attached to the tip of the probe of claim 4 are composed of at least one metal selected from palladium (Pd), platinum (Pt), gold (Au), silver (Ag), copper (Cu), nickel (Ni), zinc (Zn), and stainless steel, and an alloy.

7. In the exposure apparatus of claim 1, the probe having the function of concentrating the electromagnetic wave signal at a tip is configured to convert at least a portion of the electromagnetic wave signal into an electrical signal, transmit it to an electrical signal detection unit, and identify the composition of the object to be exposed.

8. In the exposure apparatus according to claim 1, the probe having the function of concentrating the electromagnetic wave signal at a tip is configured to scatter at least a part of the electromagnetic wave signal and transmit it to an electromagnetic signal detection unit, thereby enabling the composition of the exposure object to be identified.

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