JP2000081382A - Scanning probe, device using it, and semiconductor device and fine-structured element manufactured by device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately maintain the performance of a scanning probe used for evaluating and forming a fine-structured pattern of nanometer or less for a long time. SOLUTION: A wafer 65 that is coated with a resist 33 is placed on a stage 72, and also an ultraviolet-ray irradiation means 86 for washing a probe 62 for alignment where a film that causes photocatalysis reaction with ultraviolet rays is formed at a tip part surface and a probe 95 for exposure and provided. The scattered light of near-field light 68 being generated from irradiation light 74 being applied to an alignment mark 61 from an excitation light irradiation means 71 is guided to a detector 137 via a fiber 87 of the probe 62 for alignment. Exposure light generated by an exposure light source 91 is guided via fiber 92, and is leaked from the tip part of the probe 95 for exposure as near- field light 98.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning probe used for exposing or observing a fine pattern structure on the order of nanometers, for example, a microscope having a resolution of the order of molecular atoms and an exposure apparatus for manufacturing semiconductor devices. This is suitable for sequentially forming fine electronic circuit patterns formed on the object surface.

[0002]

2. Description of the Related Art Recently, STM (scanning tunneling microscope) and AFM have been used as microscopes having a resolution on the order of nanometers using a scanning probe that is scanned.
Atomic force microscopes and near-field light microscopes have attracted attention, and among them, near-field light microscopes that can evaluate physical properties of materials have attracted particular attention.

[0003] In fine processing, there are an optical stepper and an electron beam exposure apparatus. In an optical stepper, an auxiliary pattern, deformed illumination, and the like have been used to cover the diffraction limit of light as much as possible, and the exposure wavelength has been shortened. Wavelength 193nm from KrF excimer laser with wavelength 248nm
m ArF excimer lasers are candidates.

Further, electron beam exposure apparatuses have been improved to increase the current density in order to improve the throughput.

Further, in order to form such a fine pattern, high-precision positioning (alignment) is required. Conventionally, in a high-precision position detecting apparatus, an alignment mark is provided on an object, The optical image of
In general, a method of detecting the position of an object by detecting with a V camera, performing image processing (Japanese Patent Application No. Hei 1-198261).
Reference).

[0006]

However, a fine pattern that does not cause blurring of an optical image by the above-described conventional optical stepper has a limit of about half the wavelength, and it is impossible to expose a fine pattern on the order of nanometers. Met. Also, in an electron beam exposure apparatus, it was difficult to expose a fine pattern on the order of nanometers due to blur due to the Coulomb effect. Furthermore, for exposure on the order of nanometers,
Although it is necessary to position a pattern with an accuracy of nanometers or less and perform exposure, the conventional alignment method has insufficient accuracy, and it has been difficult to form a desired fine pattern at a desired position.

In the near-field light system such as the near-field light microscope and the near-field exposure device, a sample or an organic substance in the atmosphere adheres to a scanning probe, which is a means for irradiating a near-field light beam. There was a problem that performance deteriorated when used for a long time.

Therefore, the present invention provides a scanning probe capable of satisfactorily evaluating and forming a fine structure pattern of nanometers or less for a long period of time, and a scanning apparatus, an exposure apparatus, a near-field microscope, an alignment system, a scanning tunneling using the scanning probe. It is an object to provide a microscope and an atomic force microscope.

[0009]

According to the present invention, there is provided a scanning probe for scanning a surface of a sample, wherein a photocatalytic film covering at least a tip portion of the scanning probe is formed. .

In the scanning probe of the present invention configured as described above, a photocatalytic film covering at least the tip of the scanning probe is formed. For this reason,
By using a photocatalyst that reacts with ultraviolet light or the like having a cleaning effect, ultraviolet cleaning can be performed.

The photocatalytic film may have a property of causing a photocatalytic reaction with ultraviolet light, and the scanning probe of the present invention may have a metal film formed under the photocatalytic film.

The metal film is formed on the surface of the optical fiber,
The near-field light may be exuded from the distal end face of the optical fiber, or the metal film may be formed on the surface of the optical fiber and emit light in the near-field light generated by irradiating the sample with light. The scattered light generated by inserting the tip of the fiber may be guided to the optical fiber.

[0013] The scanning probe of the present invention comprises a trap irradiated from a trap light source for irradiating light for trapping fine particles in near-field light generated by irradiating a sample with light irradiated from a light source. By light
It may be made of fine particles that generate scattered light by being trapped and have a photocatalytic function.

The scanning device of the present invention has the scanning probe of the present invention, and the scanning probe of the present invention and scanning means for relatively scanning the surface of the sample, and irradiates the scanning probe with ultraviolet light. It may have a means.

An exposure apparatus according to the present invention includes a light irradiating means for irradiating light to an alignment mark of an object on which an alignment mark for positioning is provided, and an exposure apparatus for generating exposure light for exposing the object to be exposed. A light generating means, and a light irradiating means, an exposure light generating means, and a scanning means for relatively scanning the surface of the sample. Having a scanning probe that oozes near-field light from the light source, or the exposure light generating unit guides scattered light generated in the near-field light to the optical fiber among the scanning probes of the present invention. Having a scanning probe as an exposure probe,
Alternatively, the light irradiation means has, as a positioning probe, a scanning probe that exudes near-field light from the distal end surface of the optical fiber among the scanning probes of the present invention, and the exposure light generating means has the scanning light of the present invention. Among the probes, a scanning probe for guiding scattered light generated in near-field light to an optical fiber is provided as an exposure probe.

In the exposure apparatus of the present invention, the exposure light may be ultraviolet light, the positioning probe and the exposure probe may have the same structure, and the scanning probe may be irradiated with ultraviolet light. It may have an ultraviolet irradiation means.

[0017] The near-field microscope of the present invention comprises: an excitation light irradiating means for generating near-field light by irradiating a sample with light;
In a near-field microscope having an observation unit for observing the surface of the sample and a scanning unit that relatively scans the observation unit and the surface of the sample, the observation unit is an optical fiber of the scanning probe of the present invention. It may have a scanning probe that oozes out near-field light from the tip surface or a scanning probe that uses fine particles, and may have an ultraviolet irradiation unit that irradiates the scanning probe with ultraviolet light.

An alignment system according to the present invention is an alignment system that performs positioning using an alignment mark, and includes the near-field microscope according to the present invention.

In the scanning tunneling microscope of the present invention, while maintaining the distance between the conductive sample and the probe such that the tunnel current flowing between the surface of the conductive sample and the probe becomes a constant value, In a scanning tunneling microscope having observation means for observing the surface of a conductive sample by scanning the surface of the sample, and scanning means for relatively scanning the surface of the conductive sample and the probe, the probe is The scanning probe of the present invention may be a scanning probe having a gold film and a photocatalyst film formed on the surface thereof, and may have an ultraviolet irradiation means for irradiating the scanning probe with ultraviolet light.

An atomic force microscope according to the present invention is an atomic force microscope having a contact probe that comes into contact with the surface of a sample and a scanning unit that relatively scans the probe with the surface of the sample. The scanning probe of the present invention may be a scanning probe having a gold film and a photocatalyst film formed on the surface thereof, and may have an ultraviolet irradiation means for irradiating the scanning probe with ultraviolet light.

The semiconductor device of the present invention is manufactured using the exposure apparatus of the present invention.

Further, the fine structure element of the present invention is manufactured using the exposure apparatus of the present invention.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In recent years, an alignment method using a confocal system has been proposed as a technique which exceeds the accuracy limit due to image blur hit by the wavelength limit of alignment light. In this confocal system, the illumination area with respect to the sample is a minute spot, and a minute aperture is also provided on the light receiving side to cut off the spread due to diffraction and receive light. This is to obtain a dimensional image.

A normal confocal system uses propagating light, but in order to see or create a finer structure, it clings to the vicinity of a near-field material and usually does not propagate, but a small object close to it. Is used to detect the scattered light generated by inserting.

FIG. 1 shows a principle diagram of exposure using near-field light by the near-field light exposure apparatus using this near-field.

This near-field light exposure apparatus uses near-field light 108 that does not propagate and spreads in the order of wavelength from a substance for exposure.

The near-field light exposure apparatus is provided so as to be drivable by an exposure light source 151 for generating exposure light, a stage driving system 113, a detection light source 117 for shear force control, a piezoelectric element 119, and a stage driving system 113. Stage 11
2 and the exposure probe 15 connected to the piezoelectric element 119
And 5.

The exposure light source 151, the stage drive system 113, the shear force control detection light source 117, and the piezoelectric element 119 are controlled by the overall control system 107.

With the above configuration, the exposure light emitted from the exposure light source 151 passes through the fiber 152 and
The near-field light 108 guided to the etched exposure probe 155, which is the tip of the exposure probe 155, and extruded from the nanometer-order minute opening at the tip of the exposure probe 155 is applied to the resist 133 on the wafer 105. The resist 133 is exposed by approaching in the order of nanometers. By controlling the intensity of the near-field light 108 while relatively moving the exposure probe 155 and the wafer 105, a desired pattern can be formed on the wafer 105.

When the exposure probe 155 is driven to the fine position with respect to the surface of the wafer 105 during the exposure, the exposure probe 15
5 is performed by the piezoelectric element 119 provided on the supporting portion. The piezoelectric element 119 can perform not only the scanning of the surface of the wafer 105 but also the minute vibration of the exposure probe 155 required for the shear force detection described below.

The distance between the exposure probe 155 and the wafer 105 is controlled by a shear force detection system including a shear force control detection light source 117 and a position detector 118.

The shear force detection means that when the exposure probe 155, which has been vibrated minutely by the piezoelectric element 119, approaches the wafer 105, the atomic force between the exposure probe 155 and the wafer 105 causes the exposure probe 155 to move. This is to detect a shift amount of the resonance frequency caused by suppressing the minute vibration. The shift amount is detected by irradiating the exposure probe 155 with detection light 135 from the shear force control detection light source 117 and detecting the light passing through both ends of the exposure probe 155 with the position detector 118.

An embodiment of the present invention described below uses this near-field technique, and an embodiment of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 2 shows a main configuration diagram of a near-field exposure apparatus of the present embodiment.

The near-field exposure apparatus of this embodiment includes a stage drive system 73, an alignment measurement system 140, and an exposure system 1
41, and ultraviolet irradiation means 86, which are controlled by the overall control system 67a.

The stage drive system 73 includes an overall control system 67a.
The stage 72 is driven in response to a control command from the CPU. A wafer 65 coated with the resist 33 is placed on the stage 72, and an ultraviolet irradiation unit 86 that irradiates the alignment probe 62 and the exposure probe 95 with ultraviolet light is provided. Further, an alignment mark 61 is formed on the wafer 65.

The alignment measuring system 140 includes the piezoelectric element 7
9a, an alignment probe 62 for scanning the surface of the resist 33, a detector 137 for detecting light guided through the fiber 87, a shear force control detection light source 77a and a position detector 78a used for shear force detection. And an excitation light irradiating means 71 for irradiating the alignment mark 61 on the wafer 65 mounted on the stage 72 with light.

As shown in FIG. 3, the tip of the alignment probe 62 is such that a fiber 27 having a small opening 30 at its end is coated with gold 28 and a photocatalyst 29.

After the tip of the fiber 27 is sharpened by etching, the periphery of the alignment probe 62 is covered with gold 28, and then the tip is about 10 nm.
The micro-aperture 30 is formed by peeling the gold 28 only in the region of, and is further formed by covering the outside with TiO _{2 as the} photocatalyst 29.

At the time of alignment before exposure, when a substance is irradiated with light, a minute object is brought close to a polarization field that spreads in the range of the wavelength order near the surface of the substance, thereby causing scattered light to generate optical information of the object. By obtaining the distribution,
A position detection system having a resolution on the order of molecules is configured, and positioning is performed based on the alignment signal.

Since the resolution of the alignment system using the near-field light 68 is determined by the size of the opening of the alignment probe 62 irrespective of the alignment wavelength, it is necessary to construct an optical system that can be resolved to a wavelength much smaller than the wavelength. Is possible. Such a fine alignment system on the order of nanometers is equipped with a pre-alignment system for performing rough positioning before performing operations within the measurement range, so that practical alignment with sub-nanometer alignment accuracy is possible. An exposure apparatus can be provided.

An ultraviolet irradiation means 86 is arranged on a stage 72 on which the wafer 65 is placed. After the alignment and exposure are completed, the stage 72 is moved and the ultraviolet irradiation means 8 is moved.
The configuration is such that the alignment probe 62 comes directly above the reference numeral 6.

FIG. 4A shows a pre-alignment mark 81 and an alignment mark 61 used at the time of alignment.
FIG. 4B shows an enlarged view of the alignment mark 61, respectively.

As shown in FIG. 4A, a cross mark having a width of 2 μm is a pre-alignment mark 81 in a square area of 20 μm square having an outer peripheral portion having a width of 2 μm, and an area where the cross mark intersects. The alignment mark 61 is formed by arranging a 100 nm dot pattern in a cross shape at the center of the mark.

The pre-alignment mark 81 is used for rough positioning before near-field light alignment is performed. In near-field light alignment, a dot pattern at the center of the same mark is used.

On the wafer 65, the alignment marks 6
Although a plurality of 1s are formed, the alignment mark 61 having the pre-alignment mark 81 is provided at only two positions, and the others are all alignment marks 61 formed of a dot pattern.

Next, the alignment by the alignment measurement system 140 will be described.

The irradiation light 74 irradiated from the light irradiation means 71
Is near-field light 6 that is diffracted, scattered, or absorbed by the alignment mark 61 and partly clings to the vicinity of the substance.
It becomes 8. By inserting the alignment probe 62 into this region, a new field is formed by the interaction between the alignment probe 62 and the near-field light 68, and scattered light (not shown) generated by being scattered in accordance with the change.
Is guided into the fiber 87. The scattered light is guided to the detector 137 via the fiber 87, and is output by the detector 137 as an image signal to the image processing system 67b of the overall control system 67a, where the image is processed.

In this embodiment, the excitation light irradiation means 7
The wavelength of the irradiation light 74 from 1 was 1550 nm. This is because the thickness of the resist 33 is about 0.5 μm, and irradiation with a wavelength longer than the thickness of the resist 33 is performed so that the near-field region from the alignment mark 61 under the resist 33 spreads to near the surface of the resist 33. The light 74 is used. Detection light 7 from shear force control detection light source 77a
Semiconductor laser light having a wavelength of 630 nm was used as the wavelength 5a.

In the near-field light detection, a filter that transmits only the wavelength of the near-field light 68 (not shown) is used to reduce noise in the near-field signal. Near-field light 68
Is determined by the size of the minute aperture 30 of the alignment probe 62. In the present embodiment, the opening diameter of the minute opening 30 is about 10 nm, but the positional accuracy obtained by this is 1 nm.

After the alignment is completed using the predetermined alignment mark 61 in this manner, near-field light exposure is performed.

As shown in FIG. 2, the exposure system 141 includes an exposure light source 91 for generating exposure light, an exposure probe 95 for emitting near-field light, and an exposure light source 91 from the exposure light source 91.
, A shear force detecting piezoelectric element 79b, and a shear force control detection light source 7.
7b and a position detector 78b for detecting the detection light 75b.

A KrF excimer laser is used as the exposure light source 91, and the wavelength of the exposure light is 248 nm. The minimum line width to be exposed is approximately the size of the opening, and is 10 nm. The exposure light emitted from the exposure light source 91
The resist 33 is exposed to the near-field light 98 which is guided to the exposure probe 95 through the small opening at the tip of the exposure probe 95, and exposes the resist 33. A desired pattern can be formed on the wafer 65 by controlling the intensity of the near-field light 98 while relatively moving the exposure probe 95 and the wafer 65. One exposure area is 10 μm
Is the corner. Adjustment of the relative height between the exposure probe 95 and the wafer 65 at that time is performed by the same shear force detection as that of the alignment system, that is, the same as in the first embodiment.

When the exposure is completed, the stage 72 is driven by the stage drive system 73, and alignment is performed using the alignment mark 61 of the exposure area to be exposed next, and then exposure is performed.

The structure of the exposure probe 95 of the exposure system is the same as that of the alignment probe 62, and the shear force detection method is the same as that of the alignment measurement system 140, so that the description is omitted.

As described above, while repeating the exposure sequentially,
The entire wafer 65 is exposed. The arrangement of the exposure area 88 and the alignment mark 61 is schematically shown in FIG. The large cross mark in the square at the left end serves both as a pre-alignment and near-field light alignment mark, and each square area in a matrix is one exposure area 88. Each exposure area 8
Alignment marks 61 are arranged at the corners of 8,
An alignment mark arrangement area 89 is formed.

As described above, after the alignment and exposure are completed, the alignment probe 62 is moved to the position of the ultraviolet irradiation means 86 by driving the stage 72, and the alignment probe 62 is cleaned by irradiating the ultraviolet light. Do.

After the alignment is completed, the alignment probe 62 is irradiated with ultraviolet rays, and the opening is cleaned by a photocatalytic reaction.

By irradiating this ultraviolet ray to the alignment probe 62 at a predetermined timing, the photocatalytic reaction is promoted.

The exposure probe 95 does not need to separately irradiate ultraviolet rays because the ultraviolet rays are radiated to the opening made of the photocatalyst at the time of exposure. However, when the exposure is not performed for a while, the ultraviolet irradiation may be performed by the same operation as the alignment probe 62 so as to appropriately promote the photocatalytic reaction.

As described above, the alignment probe 62
And the exposure probe 95 is always in a good state,
The performance of the near-field exposure apparatus of the present embodiment is also maintained for a long time.

Next, the exposure sequence of this embodiment is shown in FIG.
And a flowchart shown in FIG.

First, the wafer 65 is mounted on the stage 72 (Step 301).

Next, it is determined whether or not the alignment probe 62 needs to be cleaned by irradiating ultraviolet rays (step 302). If necessary, cleaning is performed by irradiating ultraviolet rays by the ultraviolet irradiating means 86 (step 302). Step 303).

Also, it is determined whether or not the exposure probe 95 needs to be cleaned by irradiating ultraviolet rays (step 304). If necessary, cleaning is performed by irradiating ultraviolet rays by the ultraviolet irradiating means 86. (Step 305).

Next, the irradiation light 74 irradiated from the excitation light irradiation means 71 irradiates the pre-alignment mark 81 shown in FIGS. 4 and 5 into the near-field light 68 generated by the alignment probe 62. Insert This allows
A new field is formed by the interaction between the alignment probe 62 and the near-field light 68, and scattered light (not shown) generated by being scattered due to the change is guided into the fiber 87 to perform pre-alignment. (Step 30)
6).

After the completion of the pre-alignment, the stage 72 is moved by the stage drive system 73 so that the exposure probe 95 comes to the exposure area 88 shown in FIG. 5 (step 307).

Next, using the alignment mark 61,
The alignment is performed by the alignment probe 62 (step 308).

After the completion of the alignment, the exposure probe 95
Near-field light 98 that exudes from the minute aperture at the tip of
The resist 33 applied to the surface of the wafer 65 is exposed (Step 310).

The exposure using the near-field light is performed as described above.

The opening of the exposure probe 95 used this time is about 10 nm, and the minimum line width is 10 nm. However, by further reducing the opening, exposure with a minimum line width on the order of 1 nm is possible.

By irradiating the alignment probe 62 with ultraviolet rays appropriately in parallel with the sequence, a decrease in throughput can be avoided.

The ultraviolet irradiation means 26 is provided with a stage 72
It is not necessary to arrange it above, and it may be arranged separately near the probe.

(Second Embodiment) FIG. 7 shows a main configuration diagram of a near-field microscope using the near-field optical probe 2 of the present embodiment.

The near-field microscope of this embodiment comprises a stage driving system 13, an excitation light irradiating means 11, a shear force control detecting light source 17, a piezoelectric element 19, and an ultraviolet irradiating means 2.
6 and an overall control system 7a having an image processing system 7b for processing a signal from the detector 57, which detects the detection light 35, and a stage drive system 13. The stage 12 includes the stage 12 having the ultraviolet irradiation means 26 and the near-field light probe 2 connected to the detector 57.

With the above configuration, the sample evaluation area 1 on the sample 5 placed on the stage 12 is
A near-field optical image is detected by a near-field optical system including a near-field optical probe 1, a near-field optical probe 2, and a detector 57.

As described above, the near-field microscope according to the present embodiment has basically the same configuration as the alignment measurement system 140 according to the first embodiment. , And the sample evaluation region 1 on the sample 5 is different.

Therefore, the description of the structure of the near-field optical probe 2, the method of observing the sample evaluation region 1, the shear force detection, and the cleaning of the near-field optical probe 2 by irradiating ultraviolet rays will be omitted.

In this embodiment, the excitation light irradiating means 1
The wavelength of the irradiation light 34 from 1 is 1550 nm, and the wavelength of the detection light 35 from the shear force control detection light source 17 is 63 nm.
A semiconductor laser light of 0 nm was used.

The resolution of the near-field light 8 as an image is determined by the size of the minute aperture 30 of the near-field light probe 2. In the present embodiment, the opening diameter of the minute opening 30 is about 1
0 nm, but if it is made even smaller, the number n
m can be obtained.

Next, an operation sequence of the near-field light microscope according to the present embodiment will be described with reference to FIGS.

First, the sample 5 is set on the stage 12 (Step 311).

Next, the stage 12 is moved to the stage drive system 1 so that the near-field probe 2 comes to the sample evaluation area 1 of the sample 5.
3 (Step 312).

Then, the near-field probe 2 is inserted into the near-field light 8 generated by irradiating the sample evaluation area 1 with the irradiation light 34 irradiated from the excitation light irradiation means 11. Thereby, a new field is formed by the interaction between the near-field probe 2 and the near-field light 8, and scattered light (not shown) generated by being scattered due to the change is guided into the fiber 27. Performs near-field image measurement (step 313).

After the measurement of the near-field image, the near-field probe 2
It is determined whether or not it is necessary to clean the substrate by irradiating ultraviolet rays (step 314). If necessary, the substrate is cleaned by irradiating ultraviolet rays with the ultraviolet irradiation means 26 (step 315).

As described above, the measurement of the near-field image is performed.

The near-field microscope of the present embodiment also employs a method similar to that of the first embodiment, that is, the sample 5 attached to the near-field optical probe 2 and the organic matter from the atmosphere are cleaned by ultraviolet rays from the ultraviolet irradiation means 26. Since the near-field optical probe 2 is always in a good state, the performance of the near-field microscope of the present embodiment is maintained for a long period of time.

(Third Embodiment) Next, a description will be given of a position detection apparatus using near-field light in an alignment system, which is a third embodiment of the present invention.

FIG. 9 is a principle diagram of a position detecting device using near-field light in an alignment system. The position detecting device includes a stage driving system 213 for driving a stage 212, an excitation light irradiating unit 211, and a probe 202 for detecting a near-field optical image, which are controlled by an overall control unit 207 having an image data processing system. And the condenser lens 20
3 and a near-field optical system 210 composed of a detector 204
It is composed of The wafer 205 on which the alignment mark 201 is formed is placed on the stage 212.

The difference between the near-field detection optical system 210 and the ordinary optical microscope is that a probe 202 which is a small scatterer exists on the alignment mark 201. As in the conventional optical system, the excitation light 206 emitted from the excitation light irradiation means 211 is diffracted, scattered, or absorbed by the alignment mark 201. The probe 202 interacts with this diffraction field 208 to form a new field. In this way, the scattered light 209 due to the changed field is transmitted to the lens 2.
03, and is detected by the detector 204. Therefore, the lens 203 only collects the light scattered from the probe 202 and does not need an imaging function. The resolution is different from the ordinary optical system, and is determined by the size of the probe 202 and its distance from the alignment mark 201, and does not depend on the image performance of the lens 203. This near-field optical system 2
The image data obtained in step 10 is analyzed by the image processing system of the overall control device 207, and the position of the alignment mark 201 is obtained to detect the position of the wafer 205.

After the wafer 205 is positioned by the method using the near-field light beam as described above, the wafer 205 is exposed by the near-field light beam, whereby a fine pattern on the order of nanometers is formed on the wafer 205.

Next, FIG. 10 shows a near-field detection optical system 410 according to this embodiment. This embodiment corresponds to the alignment measurement system 140 of the first embodiment.

The near-field detecting optical system 410 according to the present embodiment comprises:
An optical trapping optical system 430 for controlling the position of the fine particle probe 402, a detector 404, and excitation light irradiating means 411 for irradiating the irradiation light 406 are provided. 423, an optical trap light source 422, a second lens 421, a half mirror 420, and a first lens 403.

In this embodiment, fine particles are used as probes, and this fine particle probe 402 is used as an alignment mark 6 in the same manner as the alignment probe 62 of the first embodiment.
By placing it in the near-field light 408 from 1, the scattered light 409 due to the changed field is detected by the detector 404 through the first lens 403.

Nd: YAG as the light trap light source 422
A laser (1.06 μm: 100 mW) was used. Optical trap beam 424 emitted from optical trap light source 422
Are condensed by the second lens 424, and the half mirror 4
At 20, the light is reflected in the direction of the first lens 403,
Is irradiated on the fine particle probe 402 through the lens 403. As the fine particle probe 402, titanium oxide 20
A sphere with a diameter of nm was used.

This titanium oxide has a photocatalytic function, and the organic substances adhering to the surface receive ultraviolet rays from the ultraviolet irradiation means 426 as appropriate when not aligned, and are decomposed.

The fine particles to be optically trapped are not limited to titanium oxide, but may be any as long as they exhibit a photocatalytic reaction. Further, fine particles whose surface is coated with a photocatalyst may be used.

FIG. 11 shows the light trapping light beam 424 and the direction A of the force acting on the fine particle probe 402.

The condensed light trap light beam 424 is scattered by the fine particle probe 402 and
2 itself is attracted to the beam focus position 431 which is the center of the beam electric field distribution, moves in the direction of arrow A, and stabilizes at the particle stable position 402a (Laser Research Vol. 24, No. 1)
No. 1, pages 1139 to 1147, 1996).

The beam focus position 431 coincides with
When the position of the beam waist is adjusted by a focus position adjusting means (not shown) so that the position of the beam waist is slightly below the center of the fine particle probe 402, the fine particle probe 402 is slightly pressed on the surface of the alignment mark 401.
As a result, the distance between the surfaces of the particle probe 402 and the alignment mark 401 can be kept at zero. Using the fine particle probe 402 whose position is controlled in this way, the image of the alignment mark 401 is obtained with a precision of the order of nanometers by performing a scan at an angle of view of 100 nm by the focus position control means.

Prior to setting the wafer 405 at a roughly predetermined position, the fine particle probe 402 waits slightly above the position where the wafer 405 is set by the focus position control means so that the fine particle probe 402 The apparatus is configured to avoid interference with the wafer 405.

Although the first to third embodiments have been described with respect to the near-field probe, the cleaning of the probe with a photocatalyst is not limited to this. A probe is provided at the tip of an STM (scanning tunneling microscope) or AFM (atomic force microscope) probe, and the probe is washed by appropriately irradiating ultraviolet rays from an ultraviolet irradiation unit provided separately. Can be.

The near-field microscopes of the second and third embodiments are the same as those of the alignment measurement system 1 described in the first embodiment.
Since the basic configuration is the same as that of the sample 40, the present invention is not limited to only observation of the sample, but can be applied as an alignment system for positioning.

Next, an embodiment of a method of manufacturing a semiconductor device using the above-described exposure apparatus will be described. FIG. 12 shows a manufacturing flow of a semiconductor device (a semiconductor chip such as an IC or an LSI, or a liquid crystal panel or a CCD). In step 501 (circuit design), a circuit of a semiconductor device is designed. In step 502 (mask fabrication), a mask on which the designed circuit pattern is formed is fabricated.

In step 503 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 504 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. Next Step 50
5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 504, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation).

In step 506 (inspection), step 50
Inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in Step 5 are performed. Through these steps, a semiconductor device is completed, and this is subjected to step 7 (shipment).

FIG. 13 shows a detailed flow of the wafer process. Step 511 (oxidation) oxidizes the wafer's surface. Step 512 (CVD) forms an insulating film on the wafer surface.

In step 513 (electrode formation), electrodes are formed on the wafer by vapor deposition. Step 514 (ion implantation) implants ions into the wafer. Step 5
In step 15 (resist processing), a photosensitive agent is applied to the wafer.
In step 516 (exposure), the circuit pattern of the mask is printed and exposed on the wafer by the exposure apparatus described above.

In step 517 (development), the exposed wafer is developed. In step 518 (etching), portions other than the developed resist image are removed. Step 519
In (resist removal), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the manufacturing method of the present embodiment, it is possible to easily manufacture a highly integrated semiconductor device which has conventionally been difficult to manufacture.

The exposure apparatus shown in the first embodiment is not limited to the manufacture of semiconductor devices, but can be applied to the manufacture of fine structure elements.

[0112]

According to the present invention, since a photocatalyst film covering at least the tip portion of the scanning probe is formed, the use of a photocatalyst that reacts with ultraviolet light having a cleaning effect to clean the ultraviolet rays can be performed. It can be carried out. As a result, the scanning probe can always be maintained in a good condition, so it can be used as a probe for exposure or alignment with near-field light, or as a probe for a scanning tunneling microscope or an atomic force microscope. Can be evaluated and formed favorably for a long period of time.

Further, mass production of such fine processing on the order of nanometers has become possible, and it has become possible to produce a microstructure element exhibiting a function with a nanometer structure.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of near-field light exposure according to the present invention.

FIG. 2 is a main configuration diagram of the near-field exposure apparatus according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of a tip portion of a near-field probe.

FIG. 4 is a diagram showing a pre-alignment mark and an alignment mark.

FIG. 5 is a diagram showing an exposure area and an alignment mark arrangement area.

FIG. 6 is a diagram illustrating an exposure sequence performed by the near-field exposure apparatus according to the first embodiment.

FIG. 7 is a main configuration diagram of a near-field microscope according to a second embodiment of the present invention.

FIG. 8 is a diagram illustrating an operation sequence of the near-field microscope according to the second embodiment.

FIG. 9 is a diagram illustrating the principle of position detection using a microprobe according to the present invention.

FIG. 10 is a main configuration diagram of a near-field detection optical system according to a third embodiment of the present invention.

FIG. 11 is a diagram for explaining the force acting on the particle probe.

FIG. 12 is a flowchart showing a device manufacturing process.

FIG. 13 is a flowchart showing detailed steps of the wafer process shown in FIG.

[Explanation of symbols]

1 Sample evaluation area 2 Near field probe 5 Sample 7a, 67a, 107, 207 Overall control system 7b, 67b Image processing system 8, 68, 98, 108, 408 Near field light 11, 71, 117, 211, 411 Excitation light irradiation Means 12, 72, 112, 212 Stage 13, 73, 113, 213 Stage drive system 17, 77a, 77b, 117 Shear force control detection light source 18, 78a, 78b, 118 Position detector 19, 79a, 79b, 119 Piezoelectric Elements 26, 86, 426 Ultraviolet irradiation means 27, 87, 92, 152 Fiber 28 Gold 29 Photocatalyst 30 Micro aperture 33, 133 Resist 34, 74, 206, 406 Irradiation light 35, 75a, 75b, 135 Detection light 57, 137, 204, 404 Detector 61, 201, 401 Alignment mark 6 Alignment probe 95, 155 Exposure probe 65, 105, 205, 405 Wafer 81 Pre-alignment mark 88 Exposure area 89 Alignment mark arrangement area 91, 151 Exposure light source 140 Alignment measurement system 141 Exposure system 202, 402 Fine particle probe 203 Lens 208 Diffraction field 209, 409 Scattered light 210, 410 Near-field detection optical system 402a Particle stable position 403 First lens 420 Half mirror 421 Second lens 422 Optical trap light source 423 Optical trap light source control means 424 Optical trap light flux 430 Optical trap optical System 431 Beam focus position

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) G03F 9/00 G03F 9/00 H H01L 21/66 H01L 21/66 CF term (Reference) 2F063 AA03 AA43 BA30 DA01 DA05 EA16 EB23 FA07 NA04 2F069 AA03 AA60 BB15 CC07 GG04 GG06 GG07 GG45 HH30 JJ07 LL03 4M106 AA01 BA04 CA70 DH01 DH32 DH37 DH39 DJ03 DJ32

Claims (23)

[Claims] 1. A scanning probe for scanning a surface of a sample, wherein a photocatalytic film covering at least a tip portion of the scanning probe is formed. 2. The scanning probe according to claim 1, wherein the photocatalytic film has a property of causing a photocatalytic reaction with ultraviolet light. 3. The scanning probe according to claim 1, wherein a metal film is formed below the photocatalyst film. 4. The scanning probe according to claim 3, wherein the metal film is formed on a surface of the optical fiber, and causes near-field light to ooze out from a tip surface of the optical fiber. 5. The scattered light generated by inserting the tip of the optical fiber into near-field light generated by irradiating the sample with light, the metal film being formed on a surface of an optical fiber. 4. The scanning probe according to claim 3, wherein light is guided to the optical fiber. 6. A near-field light generated by irradiating a sample with light emitted from a light source and trapped by trap light emitted from a trap light source for irradiating light for trapping fine particles. A scanning probe comprising: the fine particles having a photocatalytic function by generating scattered light. 7. A scanning apparatus comprising: the scanning probe according to claim 1; and a scanning unit that relatively scans the scanning probe and the surface of the sample. 8. The scanning device according to claim 7, further comprising an ultraviolet irradiation means for irradiating the scanning probe with ultraviolet light. 9. A light irradiating means for irradiating light to the alignment mark of an exposure object provided with an alignment mark for positioning, and an exposure light generation for generating the exposure light for exposing the exposure object An exposure apparatus comprising: a scanning unit that relatively scans the surface of the sample with the light irradiation unit, the exposure light generation unit, and the light irradiation unit. An exposure apparatus having a probe. 10. A light irradiating means for irradiating light to the alignment mark of an exposure object provided with an alignment mark for positioning, and an exposure light generator for generating the exposure light for exposing the exposure object An exposure apparatus comprising: a light irradiation unit, an exposure light generation unit, and a scanning unit that relatively scans a surface of the sample. The exposure light generation unit exposes the scanning probe according to claim 5. An exposure apparatus characterized by having an exposure probe. 11. A light irradiating means for irradiating light to the alignment mark of an object to be exposed provided with an alignment mark for positioning, and an exposure light generator for generating the exposure light for exposing the object to be exposed An exposure apparatus comprising: a scanning unit that relatively scans the surface of the sample with the light irradiation unit, the exposure light generation unit, and the light irradiation unit for positioning the scanning probe according to claim 4. An exposure apparatus, comprising: a probe; and the exposure light generating unit having the scanning probe according to claim 5 as an exposure probe. 12. The exposure apparatus according to claim 9, wherein the exposure light is ultraviolet light. 13. The positioning probe and the exposure probe have the same structure.
3. The exposure apparatus according to claim 1. 14. The exposure apparatus according to claim 9, further comprising an ultraviolet irradiation means for irradiating the scanning probe with ultraviolet light. 15. An excitation light irradiating means for irradiating a sample with light to generate near-field light; an observation means for observing the surface of the sample; A near-field microscope comprising: a scanning unit configured to scan the scanning probe according to claim 4, wherein the observation unit includes the scanning probe according to claim 4. 16. The near-field microscope according to claim 15, further comprising an ultraviolet irradiation means for irradiating the scanning probe with ultraviolet light. 17. An alignment system for performing positioning using an alignment mark, comprising the near-field microscope according to claim 15 or 16. 18. The surface of the conductive sample while maintaining a distance between the conductive sample and the probe such that a tunnel current flowing between the surface of the conductive sample and the probe is constant. A scanning tunneling microscope having observation means for observing the surface of the conductive sample by scanning the surface of the conductive sample, and scanning means for relatively scanning the surface of the conductive sample and the probe. A scanning tunneling microscope, which is the scanning probe according to any one of claims 1 to 3. 19. The scanning tunneling microscope according to claim 18, further comprising an ultraviolet irradiation means for irradiating the scanning probe with ultraviolet light. 20. An atomic force microscope having a contact probe that contacts a surface of a sample and a scanning unit that relatively scans the surface of the sample and the probe, wherein the contact probe is one of claims 1 to 3. An atomic force microscope characterized by being the scanning probe according to any one of the above. 21. The atomic force microscope according to claim 20, further comprising an ultraviolet irradiation means for irradiating the scanning probe with ultraviolet light. 22. A semiconductor device manufactured by using the exposure apparatus according to claim 9. Description: 23. A microstructure element manufactured using the exposure apparatus according to claim 9. Description: