JP2000252563A - Laser oscillation device, aligner and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser oscillation device on which the diffusion of a plasma formed on a slot can be suppressed, and a uniform laser suppressing energy loss as much as possible can be emitted. SOLUTION: In this laser oscillation device, a plasma is grown by stimulating the laser gas in a laser tube by introducing electromagnetic wave from a wave guide 1 through a plurality of microscopic gaps 10 formed on the wall of the waveguide, and a laser beam is generated by resonating the light emitted from the plasma. A mesh shield 13 is provided in the laser tube so that the plasma stimulated on the microscopic gaps 10 is not diffused to outside the prescribed region. As the grown plasma can be suppressed to diffuse to outside the mesh shield 13, a plasma growing operation can be performed by utilyzing the introduced power to the maximum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser oscillation device for generating a laser beam by introducing an electromagnetic wave from a waveguide through a plurality of minute gaps formed in the waveguide wall into the laser tube. In particular, the present invention is suitably applied to a laser oscillation device using a microwave as an electromagnetic wave for exciting a laser gas, an exposure apparatus including the same, and a method of manufacturing a device.

[0002]

2. Description of the Related Art In recent years, so-called excimer lasers have attracted attention as the only high-power laser that oscillates in the ultraviolet region. In the electronics, chemical, and energy industries, specifically, metals, resins, and glasses are used. It is expected to be applied to processing of ceramics, semiconductors, etc., chemical reactions, and the like.

The functional principle of an excimer laser oscillation device will be described. First, Ar, K filled in the manifold
A laser gas such as r, Ne, F ₂ or the like is brought into an excited state by electron beam irradiation, electric discharge or the like. At this time, the excited F atoms combine with the inactive Kr and Ar atoms in the ground state to generate KrF ^* and ArF ^* , which are molecules existing only in the excited state. This molecule is called excimer. Excimers are unstable and immediately emit ultraviolet light and fall to the ground state. This is called bond-free transition or spontaneous emission. An excimer laser oscillation device that uses this excited molecule to amplify as light with the same phase in an optical resonator composed of a pair of reflectors and extract it as laser light It is.

[0004]

At the time of excimer laser emission, a microwave is mainly used as an excitation source of a laser gas as described above. The microwave is an electromagnetic wave having an oscillation frequency of several hundred MHz to several tens GHz. In this case, a microwave is introduced into the laser tube from the waveguide through a gap (slot) formed in the waveguide wall, thereby exciting the laser gas in the laser tube to a plasma state.

[0005] However, although plasma is generated in the vicinity of the microwave emission surface on the slot, the microwave can propagate in the plasma sheath formed on the slot, and as a result, the microwave is transmitted through the sheath region. As a result, the input power is dispersed in the short axis direction of the slot, and the input power is dispersed, so that the energy density required for excimer laser excitation cannot be satisfied. This is because, when the plasma is diffused into a wide space, the energy used for generating the plasma is dispersed, and it is difficult to realize an energy density sufficient to excite the excimer.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem. Although the present invention employs a slot array structure, it suppresses the diffusion of plasma generated on a slot,
It is an object of the present invention to provide a laser oscillating device that enables uniform laser emission with minimum energy loss, a high-performance exposure device equipped with the laser oscillating device, and a method for manufacturing a high-quality device using the exposure device. Aim.

[0007]

According to the laser oscillation device of the present invention, a laser gas in the laser tube is introduced by introducing an electromagnetic wave from the waveguide through a plurality of minute gaps formed in the waveguide wall. Excites to generate plasma,
A laser oscillation device that resonates light emitted from the plasma to generate laser light, wherein a shielding structure is provided in the laser tube so that the plasma excited on the minute gap does not diffuse outside a predetermined region. I have.

In one embodiment of the laser oscillation device of the present invention, the shielding structure is provided so as to prevent diffusion of the plasma in a direction perpendicular to a longitudinal direction of the minute gap.

In one embodiment of the laser oscillation device according to the present invention, the shielding structure comprises a metal wall disposed at a predetermined distance from the minute gap.

[0010] In one embodiment of the laser oscillation device of the present invention, the shielding structure is formed of a mesh-shaped plate.

In one embodiment of the laser oscillation device according to the present invention, the shielding structure includes a plurality of nozzles having predetermined openings.

In one embodiment of the laser oscillation device of the present invention, the nozzle is a passage for the laser gas.

In one embodiment of the laser oscillation device of the present invention, the shielding structure is constituted by a magnetic field.

An exposure apparatus according to the present invention includes the laser oscillation device as a light source that emits illumination light, a first optical system for irradiating a reticle on which a predetermined pattern is formed with illumination light from the laser oscillation device, and the reticle. And a second optical system that irradiates the illumination surface with illumination light through the reticle, and projects a predetermined pattern of the reticle onto the illumination surface to perform exposure.

According to the method of manufacturing a device of the present invention, a step of applying a photosensitive material to a surface to be illuminated,
The method includes a step of performing a predetermined pattern exposure on the irradiated surface to which the photosensitive material is applied, and a step of developing the photosensitive material that has been subjected to the predetermined pattern exposure.

In one embodiment of the device manufacturing method of the present invention, the surface to be irradiated is a wafer surface, and a semiconductor element is formed on the wafer surface.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

(First Embodiment) First, a first embodiment will be described. In the present embodiment, an excimer laser oscillation device that emits a so-called excimer laser light is exemplified.
FIG. 1 is a schematic diagram illustrating a main configuration of an excimer laser oscillation device according to the present embodiment.

As shown in FIG. 1, the excimer laser oscillation device emits laser light by resonating light emitted by the excitation of the excimer laser gas, and excites the excimer laser gas in the laser tube 2 to form a plasma state. And a cooling vessel 7 having a cooling water inlet / outlet 9 for cooling the waveguide 1.

The excimer laser gas used as a raw material for generating the excimer laser light is one or more inert gases selected from Kr, Ar and Ne, or a mixture of the one or more inert gases and F ₂ gas. It is a mixed gas. Of these, gas types may be appropriately selected and combined depending on the wavelength to be used. For example, when it is desired to generate a laser beam having a wavelength of 248 nm, Kr / Ne / F ₂ is used. For a wavelength of 193 nm, Ar / Ne / F _{2 is used} . For a wavelength of 157 nm, Ne / F ₂ is used. do it.

The laser tube 2 is provided with a laser gas inlet / outlet 8 for introducing an excimer laser gas into the tube, and reflecting structures 5 and 6 at each end. Laser light is generated with the light phases aligned.

The waveguide 1 is a means for supplying microwaves to the laser gas in the gas supply path structure 11 and is shown in FIG.
A plurality of elongated slots 10 are formed in the middle upper surface. When a microwave having a frequency of several hundred MHz to several tens GHz is introduced from the upper part of the waveguide 1, the microwave is emitted from the slot 10 to the outside of the waveguide 1 while propagating in the waveguide 1. Is done. The emitted microwave is applied to the laser tube 2
Introduced into. Then, the excimer laser gas in the laser tube 1 is excited by the introduced microwave, and resonates to generate excimer laser light.

FIG. 2 shows a specific state of the waveguide 1. Here, FIG. 2A is a schematic perspective view of the waveguide 1, FIG.
(B) is a plan view thereof.

As shown in FIG. 2B, each slot 10
Are arranged in a row such that the longitudinal direction thereof coincides with the longitudinal direction of the waveguide 1. The slots 10 are arranged along the longitudinal direction of the waveguide 12, and each has a shape extending in the longitudinal direction of the waveguide 12.

FIG. 3A shows a cross section near the laser tube 2 of the waveguide 1 in the first embodiment. here,
FIG. 3A shows a cross section along a direction perpendicular to the longitudinal direction of the slot 10.

As described above, the laser gas in the laser tube 2 is excited by the microwave radiated from the slot 10, and the plasma 11 emits light.

In the first embodiment, the mesh shield 1 surrounds a predetermined area on the slot 10.
3 are provided. The mesh shield 13 is a shield made of a metal mesh, and plays a role of suppressing the diffusion of the microwaves emitted from the slots 10.

Although a laser gas flow path is provided on the slot 10, the use of a mesh shield allows the laser gas flowing in the laser tube 2 to pass through the mesh shield 13 and reach the slot 10. Is possible.

FIG. 3B shows an example in which a metal wall 15 is further provided on the mesh shield 13 shown in FIG. Since the laser gas does not flow upward to the slot 10, the provision of the metal wall 15 makes it possible to more reliably confine the microwave.

The energy of the microwave is 1 / e while the microwave travels through the skin depth δ in the plasma in the cutoff mode.
² (≒ 0.135) reduction. Therefore, when the plasma blocks the microwave, the area where the effective plasma can be excited is the space of about 3δ at the emission end when the propagation in the sheath area can be neglected, and the plasma exists in other areas. If so, the existing plasma is a plasma due to diffusion.

Therefore, by confining the plasma in a space of δ to 3δ from the emission end, a state in which the plasma is excited in the entire space can be realized. In the example shown in FIG. 3, the mesh shield 13 is moved from the discharge end of the slot 10 to δ to 3δ.
By setting the distance of the mesh shield 13
Plasma can be excited in the entire region of the inside.

Also, when microwaves diffuse in the sheath region, the energy supply density to the plasma is reduced. As a countermeasure to prevent this, it is effective to confine the plasma with a mesh shield 13 or the like. It is.

At this time, if the cutoff wavelength of the basic structure of the shield is λc and the wavelength of the microwave leaking through the sheath region is λ, the penetration length δs into the shield is

[0034]

(Equation 1)

Is given by At this time, the ratio p between the energy of the microwave incident on the shield and the energy of the microwave leaking to the outside of the shield is defined as d, where d is the thickness of the shield.

[0036]

(Equation 2)

Is as follows. Therefore, the basic structure of the shield λc
Is determined, and when the emissivity p of the shield is determined, the minimum value of d required for the emissivity can be calculated, and therefore, the lower limit of the required shield thickness can be calculated. Conveniently, 1/4 of the wavelength in the waveguide
The shielding effect can be obtained by adopting a diameter of the order.

For example, when the leakage of electromagnetic wave energy to the outside is set to 1% or less using a mesh having a shield thickness of 1 mm, the required maximum penetration length into the shield is as follows:
0.43 mm. Assuming that the basic unit of the mesh is a rectangle and the peripheral length is a, λc = 2a. At this time, a must be 1.4 mm or less.

The structure of the present embodiment is the same as that of the slot 10
Of plasma generated by microwaves emitted from
In particular, it is possible to prevent diffusion of the microwave propagating through the sheath. Therefore, it is possible to generate plasma inside the mesh shield 13.

The plasma diffused into the mesh shield 13 acts as the inner axis of the coaxial waveguide, and as a result, the part where the plasma is diffused (the diffusion length of the plasma) operates as a coaxial waveguide, and thus the The waves are in TEM mode and propagate easily.

The propagation at this time still occurs in the sheath region, and the penetration length into the plasma is not negligible with respect to the sheath thickness. The loss due to the propagation is large, so that the propagation is attenuated at a smaller distance. This can be problematic when confining.

That is, the microwave propagates the diffusion length of the plasma in addition to the microwave cutoff length δs of the shield. From these, it is necessary to set the shield length to be longer than the cutoff length of the microwave alone + the diffusion length of the plasma.

Assuming that the surface area of the shield to be confined is S, the aperture ratio is α, the operating pressure is P, and the structure factor is k, the conductance C of gas passing through the shield (easiness of gas flow)
Is a viscous fluid,

[0044]

(Equation 3)

When the operating pressure and the shield structure are determined, the upper limit of the shield thickness can be calculated.

Since the shield length and the conductance necessary for blocking the microwave are in an inverse relationship with respect to α and d, respective optimum values can be defined from both.

The material of the shield is desirably a material having a lower resistivity in order to reduce microwave loss. In addition, a material having a low thermal resistance is desirable because the temperature is high because it is in contact with the plasma. Further, the material surface may be subjected to a fluorine passivation treatment, or the material surface may be covered with a fluorine compound.

As described above, according to the first embodiment of the present invention, by providing the mesh shield 13 so as to cover the slot 10, the plasma is diffused from the slot 10 to the side via the sheath. Can be suppressed. Further, by using the mesh shield 13, it is possible to avoid a concentration of an electric field in the plasma and realize a more uniform discharge.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 4 (b)
FIG. 7 is a perspective view showing a shielding structure for confining a plasma excited on a slot 10 in a predetermined region in the second embodiment. Note that the overall configuration of the excimer laser oscillation device according to the second embodiment is the same as that of the first embodiment, and a description thereof will be omitted. Further, in the drawings describing the second embodiment, the same reference numerals are given to substantially the same components as those in the first embodiment, and description thereof is omitted.

As shown in FIG. 4, a nozzle shield 14 is formed in the laser tube 2 on the slot 10 formed in the waveguide 1. Here, FIG. 4A is a plan view showing the nozzle shield 14 from above the slot 10, and FIG.
(B) is a perspective view showing a nozzle shield.

As shown in FIGS. 4A and 4B, the nozzle shield 14 is composed of a plurality of cylindrical nozzles 14a, and each of the nozzles 14a is a passage for a laser gas. Arrow A shown in FIG. 4B indicates the flow of the laser gas. The laser gas flows in each nozzle 14a in a direction perpendicular to the longitudinal direction of the slot 10, and is excited by the microwave radiated from the slot 10.

The nozzle shield 14 utilizes the property that microwaves cannot pass through openings smaller than a predetermined size. That is, by arranging a plurality of nozzles 14a whose apertures are set to a predetermined size with respect to the frequency of the emitted microwave, the microwave can be spatially radiated similarly to the metal wall or the mesh shield described in the first embodiment. It is possible to confine it.

Here, since the nozzle shield 14 is arranged along the flow of the laser gas, it does not hinder the flow of the laser gas. Therefore, even when performing ultra-high-speed gas replacement, resistance is hardly generated in the laser gas flow, and generation of pressure loss can be suppressed.

According to the second embodiment, confinement of plasma and confinement of microwaves can be performed more effectively than in the case where a mesh shield is used. This is because, when a mesh shield is used, microwaves can be confined alone, but if plasma diffuses and enters the mesh structure, the effect of confinement may be limited.

FIG. 5A is a schematic diagram showing a cross section along the direction of the gas flow shown in FIG. The nozzle shield 14 can suppress the diffusion of microwaves and plasma to the side of the slot 10, and can confine the excited plasma in a predetermined range on the slot 10.

FIG. 5B shows an example in which a metal wall 15 is provided on the slot 10 for the purpose of preventing microwaves and plasma from diffusing above the slot 10. Metal wall 1
5, the diffusion of microwaves and plasma not only to the side of the slot 10 but also to the upper side can be suppressed, so that the plasma can be confined within a predetermined distance from the opening end of the slot 10.

The specific configuration of the nozzle shield 14 will be described. For example, using a nozzle having a length of 20 mm, the leakage of electromagnetic waves to the outside is set to 1% or less. The maximum required penetration length into the shield at this time is 8.7 mm.

Assuming that the basic unit of the mesh is a rectangle and the length of its long side is a, λc = 2a. At this time, a is 3
Must be 0 mm or less. Therefore, a relatively wide margin of 25 mm or less can be set between the nozzles.

For example, if the nozzle wall interval is set to 20 mm, the leakage of electromagnetic waves to the outside can be kept at 1% or less even if the plasma diffuses by about 4.5 mm. In addition, the present structure has an advantage that a larger conductance can be obtained, and is more effective when flowing a high-speed gas.

Assuming that the conductance of a mesh having a basic structure of 1 mm square and 1 mm thick and the conductance of a nozzle having a basic structure of 20 mm × 2 mm and a length of 20 mm, (assuming that both the mesh and the thickness of the nozzle wall are 1 mm, The aperture ratios of both are 25% and 91%, respectively, and when they have the same cross-sectional area, the conductance of the nozzle is the thickness (length) field 2
It is 3.3 times higher than 0 times. That is, by adopting the nozzle structure, a structure in which gas can flow much more easily can be obtained. In addition to this, turbulence often occurs in an actual gas flow, and it is desirable to increase the interval between structures as much as possible in order to avoid the turbulence.

As described above, in the second embodiment, the nozzle shield 14 is formed by arranging a plurality of nozzles 14a each having an opening through which microwaves cannot pass. The laser gas can be confined in a predetermined area, and by flowing the laser gas into each nozzle 14a, no resistance is generated in the gas flow despite the provision of the shield structure. This can minimize the occurrence of pressure loss.

(Third Embodiment) Next, a third embodiment will be described with reference to the drawings. FIG. 6 is a schematic diagram showing the configuration of the magnetic field shield according to the third embodiment. FIGS. 7 and 8 are schematic diagrams showing a cross section along a direction perpendicular to the longitudinal direction of the slot 10. is there. Note that the overall configuration of the excimer laser oscillation device according to the third embodiment is also the same as that of the first embodiment, and a description thereof will be omitted. Further, in the drawings describing the third embodiment, the same reference numerals are given to substantially the same components as those in the first embodiment, and description thereof is omitted.

In the third embodiment, the slot 10
A magnetic field is used to confine the plasma excited above in a predetermined range. The magnetic field may be formed by using a solenoid as shown in FIG. 6A, or by arranging a normal magnet as shown in FIG. 6B.

FIG. 6A shows that the solenoid 1 is used for forming a magnetic field.
6 shows an example using. The arrangement of the solenoid 16 is as follows.
As shown in FIG. 6A, the solenoid 16 is arranged so that the extending direction of the solenoid 16 is the same as the laser oscillation direction. That is, the longitudinal direction of the waveguide 1 and the slot 10 shown in FIG. 2 is the same as the direction in which the solenoid 15 extends.

The magnetic field strength is determined so that the Larmor period of electrons in the magnetic field is shorter than the collision period of electrons and atoms in the plasma (magnetic field plasma conditions). The Larmor angular velocity of an electron is represented by the magnetic flux density B, the electron mass m, and the elementary charge e.

[0066]

(Equation 4)

The collision angular velocity between an electron and an atom is represented by the following equation: atomic density n, atomic radius r, electron temperature T, and Boltzmann coefficient k
As

[0068]

(Equation 5)

From these equations, considering the operating pressure of the excimer laser and the like, the magnetic flux density needs to be about 1 T or more.

When a strong magnetic field is applied by the solenoid 16, the electrons of the plasma precess along the formed magnetic flux. Since the magnetic flux is formed in the same direction as the laser oscillation direction, the electrons of the plasma are less likely to diffuse in the direction perpendicular to the laser oscillation direction, and confinement of the plasma can be realized. The magnet 17 shown in FIG.
A similar effect can be obtained even when a magnetic field is formed by using.

FIG. 7A is a schematic sectional view showing the arrangement of the solenoid 16 or the magnet 17 around the slot 10. In order to confine the plasma on the slot 10, it is desirable to provide magnets 17 at, for example, four positions so as to surround the slot 10. Thus, the generated plasma can be confined on the slot 10.

FIG. 7B shows an example in which a metal wall 15 is provided above the slot 10. The diffusion of the plasma above the slot 10 can be suppressed by the metal wall 15, and the diffusion of the plasma in the lateral direction from the slot 10 can be suppressed by the solenoid 16 or the magnet 17.

FIG. 8 shows a configuration in which a nozzle shield 14 is further added to the configuration shown in FIG. According to this configuration, it is possible to suppress the plasma from diffusing in the lateral direction of the slot 10 due to the synergistic effect of the solenoid 16 or the magnet 17 and the nozzle shield 14. As described above, in the third embodiment, it is desirable to use the shielding structure according to the first embodiment or the second embodiment together in order to compensate for the effect of confining microwaves.

As described above, according to the third embodiment, by forming a magnetic flux in the same direction as the laser oscillation direction, it is possible to prevent the plasma electrons from diffusing in the direction perpendicular to the laser oscillation direction. Thus, plasma confinement on the slot 10 can be realized.

(Fourth Embodiment) Hereinafter, a fourth embodiment will be described. In the fourth embodiment, an exposure apparatus (stepper) having the excimer laser oscillation device described in the first embodiment as a laser light source is exemplified. FIG.
FIG. 2 is a schematic diagram showing a main configuration of the stepper.

The stepper includes an optical system 1 for irradiating a reticle 101 on which a desired pattern is drawn with illumination light.
11, a projection optical system 112 for projecting illumination light through the reticle 101 to reduce and project the pattern of the reticle 101 onto the surface of the wafer 102, a wafer chuck 113 on which the wafer 102 is mounted and fixed, and a wafer It has a wafer stage 114 to which the chuck 113 is fixed. As the reticle, not only a transmission reticle (reticle 101) as shown in the figure but also a reflection reticle can be applied.

The optical system 111 includes an excimer laser oscillation device 121 according to the first embodiment, which is a light source that emits high-brightness excimer laser light as illumination light, and an illumination light from the excimer laser oscillation device 121 having a desired light beam shape. Beam shape converting means 122, an optical integrator 123 in which a plurality of cylindrical lenses and minute lenses are arranged two-dimensionally, and a switch (not shown) which can be switched to an arbitrary aperture. A diaphragm member 124 disposed near the position of the formed secondary light source, a condenser lens 125 for condensing illumination light passing through the diaphragm member 124,
A blind 127 constituted by a plurality of variable blades and arranged on a conjugate plane of the reticle 101 to arbitrarily determine an illumination range on the surface of the reticle 101;
An imaging lens 128 for projecting the illumination light determined in the predetermined shape on the surface of the reticle 101;
And a folding mirror 129 that reflects the illumination light from the reticle 101 toward the reticle 101.

The operation of reducing and projecting the pattern of the reticle 101 onto the surface of the wafer 102 using the stepper configured as described above will be described.

First, the illumination light emitted from the light source 121 is converted into a predetermined shape by the beam shape conversion means 122 and then directed to the optical integrator 123. At this time, a plurality of secondary light sources are formed near the exit surface. Illumination light from the secondary light source is condensed by the condenser lens 125 via the aperture member 124 and is
After being determined to have a predetermined shape, the light is reflected by the bending mirror 129 via the imaging lens 128 and enters the reticle 101. Subsequently, the light passes through the pattern of the reticle 101 and enters the projection optical system 122. Then, the projection optical system 122
, The pattern is reduced to a predetermined size, projected onto the surface of the wafer 102, and exposed.

According to the stepper of this embodiment, since the excimer laser oscillation device of the first embodiment is used as a laser light source, high-output and uniform excimer laser light can be emitted for a relatively long time. Can be quickly and accurately performed.

Next, an example of a method for manufacturing a semiconductor device (semiconductor device) using the projection exposure apparatus described with reference to FIG. 10 will be described.

FIG. 10 shows a semiconductor device (IC or LSI)
2 shows a flow of a manufacturing process of a semiconductor chip such as a liquid crystal panel or a CCD. First, in step 1 (circuit design), a circuit of a semiconductor device is designed. Step 2 is a process for making a mask on the basis of the circuit pattern design. On the other hand, in step 3 (wafer manufacturing), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is referred to as a pre-process, and actual circuits are formed on the wafer by photolithography using the mask and wafer prepared as described above. The next step 5 (assembly) is called a post-process, and step 4
This is a process of forming a semiconductor chip using the wafer produced by the above, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). In step 6 (inspection), 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 shipped (step 7).

FIG. 11 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. In step 12 (CVD), a conductive film or an insulating film is formed on the wafer surface by using a gas phase reaction. Step 1
In 3 (PVD), a conductive film or an insulating film is formed on a wafer by sputtering or vapor deposition. Step 14 (ion implantation) implants ions into the wafer. Step 15
In (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the projection exposure apparatus described above to expose the circuit pattern of the mask onto the wafer by printing. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), the unnecessary resist after etching is removed.
By repeating these steps, multiple circuit patterns are formed on the wafer.

By using this manufacturing method, a highly integrated semiconductor device, which has conventionally been difficult to manufacture, can be manufactured easily and reliably with a high yield.

[0085]

According to the present invention, it is possible to prevent the plasma from diffusing out of the predetermined range from above each slot. Accordingly, it is an object of the present invention to provide a laser oscillation device which enables uniform laser emission with minimum energy loss, a high-performance exposure device equipped with the laser oscillation device, and a method for manufacturing a high-quality device using the exposure device. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a main configuration of an excimer laser oscillation device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a specific state of a waveguide of the excimer laser oscillation device according to the first embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a shielding structure in the laser oscillation device according to the first embodiment of the present invention.

FIG. 4 is a schematic sectional view showing a shielding structure in the laser oscillation device according to the first embodiment of the present invention.

FIG. 5 is a schematic sectional view illustrating a shielding structure in a laser oscillation device according to a second embodiment of the present invention.

FIG. 6 is a schematic diagram showing a shielding structure in a laser oscillation device according to a third embodiment of the present invention.

FIG. 7 is a schematic sectional view showing a shielding structure in a laser oscillation device according to a third embodiment of the present invention.

FIG. 8 is a schematic sectional view showing a shielding structure in a laser oscillation device according to a third embodiment of the present invention.

FIG. 9 is a schematic view showing a stepper according to a fourth embodiment of the present invention.

FIG. 10 is a flowchart of a semiconductor device manufacturing process using a stepper according to a fourth embodiment of the present invention.

FIG. 11 is a flowchart showing the wafer process in FIG. 10 in detail;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Waveguide 2 Laser tube 5, 6 Reflection structure 7 Cooling container 8 Laser gas inlet / outlet 9 Cooling water inlet / outlet 10 Slot 11 Plasma 13 Mesh shield 14 Nozzle shield 14a Nozzle shield 15 Metal wall 16 Solenoid 17 Magnet 101 Reticle 102 Wafer 111 Optical system 112 Projection optical system 113 Wafer chuck 114 Wafer stage 121 Excimer laser oscillation device 122 Beam shape conversion means 123 Optical integrator 124 Aperture member 125 Condenser lens 127 Blind 128 Imaging lens 129 Folding mirror

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) H01S 3/225 H01S 3/223 E (72) Inventor Masaki Hirayama 52 Shosen Aihara, Wakabayashi-ku, Sendai City, Miyagi Prefecture No. 103 (72) Inventor Toshinobu Shinohara 2-2-4-44-303, Odawara, Miyagino-ku, Sendai-shi, Miyagi Prefecture (72) Inventor Nobuyoshi Tanaka 3- 30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Nobumasa Suzuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Dai Osawa 3-30-2, Shimomaruko 3-chome, Ota-ku, Tokyo F-term (reference) 2H097 BA02 BA06 CA13 JA03 LA10 5F046 AA07 BA04 CA04 5F071 AA06 DD08 EE04 JJ05 JJ10 5F072 AA06 JJ02 JJ05 KK06 MM08 PP05

Claims (10)

[Claims] An electromagnetic wave is introduced into a laser tube from a waveguide through a plurality of minute gaps formed in the waveguide wall to excite a laser gas in the laser tube to generate plasma, and to generate plasma from the plasma. A laser oscillation device that resonates emitted light to generate laser light, wherein a shielding structure is provided in the laser tube so that the plasma excited on the minute gap does not diffuse outside a predetermined region. Laser oscillation device. 2. The apparatus according to claim 1, wherein the shielding structure is provided so as to prevent diffusion of the plasma in a direction perpendicular to a longitudinal direction of the minute gap.
3. The laser oscillation device according to claim 1. 3. The laser oscillation device according to claim 1, wherein the shielding structure is formed of a metal wall disposed at a predetermined distance from the minute gap. 4. The laser oscillation device according to claim 1, wherein the shielding structure is formed of a mesh-shaped plate. 5. The laser oscillation device according to claim 1, wherein the shielding structure includes a plurality of nozzles having a predetermined opening. 6. The laser oscillation device according to claim 5, wherein the nozzle is a passage for the laser gas. 7. The laser oscillation device according to claim 1, wherein the shielding structure is constituted by a magnetic field. 8. A light source for emitting illumination light.
The laser oscillation device according to any one of the above, a first optical system that irradiates a reticle on which a predetermined pattern is formed with illumination light from the laser oscillation device, and illuminating light that has passed through the reticle is applied to a surface to be irradiated. Second to irradiate
An exposure apparatus, comprising: an optical system, wherein a predetermined pattern of the reticle is projected onto the surface to be irradiated to perform exposure. 9. A step of applying a photosensitive material to a surface to be irradiated, and a step of exposing a predetermined pattern to the surface to be irradiated with the photosensitive material using the exposure apparatus according to claim 8. Developing the photosensitive material to which the predetermined pattern has been exposed. 10. The device manufacturing method according to claim 9, wherein the irradiated surface is a wafer surface, and a semiconductor element is formed on the wafer surface.