JP2021106240A - Gas supply device and surface treatment method - Google Patents

Abstract

To provide a gas supply device that is able to blow a gas containing a radical to an object at a high concentration compared with a conventional one.SOLUTION: A gas supply device comprises: a first gas inflow port through which a first gas containing oxygen serving as a radical source is flowed in; a second gas inflow port through which a second gas lower in oxygen concentration than the first gas is flowed in; a first gas flow passage through which the first gas flowed in from the first gas inflow port flows; a light source that emits ultraviolet light toward an emission area in the first gas flow passage; a gas mixing portion in which the first gas and the second gas after passing through at least a part of the emission area are mixed; and a gas outflow port through which the mixed gas after being mixed in the gas mixing portion is flowed out.SELECTED DRAWING: Figure 1A

Description

The present invention relates to a gas supply device, and more particularly to a device that causes a photochemical reaction with a substance contained in a gas by irradiating the gas with ultraviolet light. The present invention also relates to a method for treating the surface of an object by spraying the gas after the photochemical reaction onto the object.

Conventionally, for the purpose of removing organic compounds adhering to the surface of an object, a technique of activating the gas by irradiating the gas with vacuum ultraviolet light and spraying the activated gas on the surface of the object. Is known (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2007-98357

However, according to the diligent research of the present inventors, it was found that the structure described in Patent Document 1 cannot blow a gas containing a high concentration of radicals onto the object. The reason for this is that, in the structure described in Patent Document 1, the present inventors have a light source for irradiating the gas with ultraviolet light to generate radicals, and an installation location of an object to which the gas containing radicals is blown. It is speculated that many of the radicals are deactivated before the gas reaches the object because they are too far apart.

In view of the above problems, an object of the present invention is to provide a gas supply device capable of blowing a gas containing radicals at a higher concentration than the conventional one onto an object. Another object of the present invention is to provide a method capable of treating the surface of an object with a gas containing radicals at a higher concentration than before.

The gas supply device according to the present invention
The first gas inlet, where the first gas containing oxygen, which is a radical source, flows in,
A second gas inlet, which is provided at a location different from the first gas inlet and into which a second gas having a lower oxygen concentration than the first gas flows in.
The first gas flow path through which the first gas flowing in from the first gas inflow port flows,
A light source that emits ultraviolet light toward the irradiation region in the first gas passage, and
A gas mixing section in which the first gas and the second gas are mixed after passing through at least a part of the irradiation region.
It is characterized by including a gas outlet that allows the mixed gas after being mixed in the gas mixing section to flow out to the outside.

In the present specification, "radical" refers to a concept that collectively refers to chemical species (atoms, molecules) having unpaired electrons, and an example of these is an oxygen radical such ^{as O (3 P).} In this case, examples of the first gas as a raw material for radicals include a mixed gas containing oxygen and air.

According to the above configuration, the first gas flowing through the first gas passage is irradiated with ultraviolet light to photodecompose radical raw materials in the gas to generate radicals, and becomes a gas containing radicals. Change. This gas is mixed with a second gas having a lower oxygen concentration than the first gas in a gas mixing portion located in front of the gas outlet. As the second gas _{, an inert gas such as N 2} , Ar, or Ne, a gas in which a plurality of types of inert gases are mixed, or a mixed gas in which the inert gas contains a low concentration of oxygen can be adopted. ..

^{By the way, O (3} P), which is one of the oxygen radicals, has extremely high activity _{and causes a reaction with surrounding oxygen (O 2} ) as shown in the following equation (1). When such a reaction occurs, the concentration of oxygen radicals contained in the gas decreases. The rate of this reaction is proportional to the concentration of _{O 2.}
O ( ³ P) + O ₂ → O ₃ ‥‥ (1)

On the other hand, as in the above configuration, the first gas containing radicals is mixed with the second gas having a low oxygen concentration at a position in front of the gas outlet, so that the concentration of _{O 2 contained in this mixed gas is high.} Is reduced. As a result, since the progress rate of the reaction in (1) above is suppressed, it is possible to blow the gas onto the object while suppressing the rate of decrease of oxygen radicals by letting the gas flow out from the gas outlet. Become.

Conventionally, an apparatus for generating a gas containing radicals using plasma is known, but in such a case, ions are inevitably generated, so that charged particles adhere to the object and the charged particles adhere to the object. It may change the physical properties of the object. However, according to the above device that generates a gas containing radicals by irradiating the raw material gas with ultraviolet light, ions are not generated, so that it is possible to prevent charged particles from being sprayed on the object together with the gas. NS.

The gas containing a high concentration of radicals flowing out from the gas outlet of the gas supply device can be used for purposes such as cleaning, reforming, and sterilizing an object.

In the gas mixing section, the first gas may be mixed with the second gas flowing in a direction substantially orthogonal to the flow path direction of the first gas.

As used herein, the term "substantially orthogonal" between the first direction and the second direction means that the angle formed by the two directions is within the range of 70 ° to 110 °.

With such a configuration, the first gas is sufficiently mixed with the second gas in the gas mixing section, and the effect of delaying the progress of the reaction defined by the above equation (1) is enhanced.

As one of the more specific configuration examples, a method can be adopted in which the flow direction of the second gas itself is set to a direction non-parallel to the flow direction of the first gas. As another configuration example, the flow direction of the second gas is substantially parallel to the flow direction of the first gas, and is located upstream of the gas mixing portion in the gas supply device. A windbreak wall where the second gas collides is provided at the position of, and the flow direction of the second gas after the collision with the windbreak wall is changed to a direction substantially orthogonal to the flow direction of the first gas. After that, a method of leading to the gas mixing section can be adopted.

The gas supply device includes a second gas passage through which the second gas flowing in from the second gas inflow port passes.
The second gas passage may be connected to the gas mixing portion at a position closer to the gas outlet side than the irradiation region.

In this case, the second gas passage may be arranged on the outside so as to sandwich or surround the first gas passage.

As a more specific embodiment
The gas supply device has a housing in which the light source is built-in.
The light source has a light emitting tube in which a hollow tubular space is formed through the tube axis direction, and a light emitting surface formed along the space on the tubular space side of the light emitting tube.
The first gas passage is formed in the tubular space surrounded by the light emitting surface.
The second gas passage may be formed in a region sandwiched between the outer wall of the arc tube and the inner wall of the housing.

For example, a double-tube type excimer lamp can be adopted as a light source, and a configuration in which the first gas passes through the inside of the inner tube and the second gas flows through the outside of the excimer lamp can be adopted. In this case, the arc tube of the excimer lamp is cooled by the second gas, and the luminous efficiency can be improved.

As another specific aspect,
The gas supply device has a housing in which the light source is built.
The housing is
A first wall body forming a first space in which the light source is arranged, and
It has a second wall body that is arranged outside the first wall body and forms a second space with the first wall body.
The light source has a light emitting tube formed along the tube axis direction and a light emitting surface formed along the outer surface of the light emitting tube.
The first gas passage is formed in a region sandwiched between the outer wall of the arc tube and the first wall body.
The second gas passage may be formed in a region sandwiched between the first wall body and the second wall body.

In the case of such a configuration, for example, as the light source, excimer lamps having various structures that emit ultraviolet light toward the outside of the arc tube can be adopted. Then, the first gas flows to the outside of the excimer lamp, and the second gas flows to the outside of the excimer lamp.

As another aspect, the first gas passage may be arranged outside so as to sandwich or surround the second gas passage.

The light source can adopt a structure exhibiting a long shape. In this case, the first gas may flow along the long direction of the light source, or may flow along the direction orthogonal to the long direction.

As an example of the former, the light source has a shape in which the direction parallel to the first direction from the first gas inlet to the gas outlet is the longitudinal direction.
Both the first gas and the second gas may reach the gas mixing portion after flowing in a direction parallel to the first direction.

As an example of the latter, the light source has a shape in which the direction orthogonal to the first direction from the first gas inlet to the gas outlet is the longitudinal direction.
Both the first gas and the second gas may reach the gas mixing portion after flowing in a direction parallel to the first direction.

Even in these cases, the second gas flows in a direction parallel to the first direction, and then the traveling direction is changed before reaching the gas mixing portion, and the direction is not parallel to the flow direction of the first gas. It does not matter if it is guided to the gas mixing section.

In the first gas passage, the passage region located on the gas mixing portion side may have a smaller flow path cross-sectional area than the passage region located on the gas inlet side.

According to the above configuration, after the first gas is irradiated with ultraviolet light, the flow velocity when flowing toward the gas mixing portion is increased, and the gas flows out from the gas outlet with this high flow velocity. As a result, the time from the irradiation of the first gas with ultraviolet light to the outflow from the gas outlet is shortened, and the time from the start of the outflow from the gas outlet to the arrival at the object is shortened. Time is also shortened. As a result, the time required for the reaction defined by the above equation (1) to occur before reaching the object is shortened, and a gas (mixed gas) containing a higher concentration of radicals than before can be sprayed on the object. can.

The gas mixing portion may have a shape in which the cross-sectional area of the flow path is continuously or intermittently reduced toward the gas outlet.

According to this configuration, the first gas after being mixed with the second gas flows out from the gas outlet with a high flow velocity, and therefore, it is defined by the above equation (1) before reaching the object. The time required for the reaction to occur is shortened, and a gas containing a higher concentration of radicals (mixed gas) can be sprayed onto the object.

The ultraviolet light emitted from the light source may have a main emission wavelength of less than 230 nm.

In the present specification, the “main emission wavelength” is 40% of the total integrated intensity in the emission spectrum when the wavelength range Z (λ) of ± 10 nm with respect to a certain wavelength λ is defined on the emission spectrum. It refers to the wavelength λi in the wavelength region Z (λi) showing the above integrated intensity. For example, in a light source having an extremely narrow half-value width and showing light intensity only at a specific wavelength, such as an excimer lamp in which a predetermined luminescent gas is sealed, the wavelength having the highest relative intensity (main peak) is usually used. Wavelength) may be used as the main emission wavelength.

The light source may be, for example, an excimer lamp that employs a gas containing at least one material belonging to the group consisting of Xe, Ar, Kr, ArBr, ArF, KrCl, and KrBr as the light emitting gas. For example, according to an excimer lamp containing Xe as a luminescent gas, the main emission wavelength of ultraviolet light is 172 nm.

According to this configuration, by installing the treatment target at a position 10 mm away from the gas outlet, the gas (mixed gas) containing a high concentration of radicals can be sprayed onto the treatment target. ..

Further, the present invention is a method for treating the surface of an object.
The step (a) of allowing the first gas containing oxygen, which is a radical source, to flow into the first gas passage, and
The step (b) of irradiating the first gas flowing through the first gas flow path with ultraviolet light from a light source, and
After the step (b), a step (c) of mixing the first gas with a second gas having a lower oxygen concentration than the first gas is added.
It is characterized by having a step (d) of spraying the mixed gas obtained in the step (c) onto the surface of the object.

In the above case, the step (c) may be performed at a position between the housing containing the light source and the object, or may be performed inside the housing.

According to the gas supply device of the present invention, a gas containing radicals (mixed gas) having a higher concentration than the conventional one can be discharged from the gas outlet, and the gas can be blown onto the object. ..

It is sectional drawing which shows typically the structural example of the 1st Embodiment of a gas supply apparatus. It is the drawing which omitted the illustration of the light source 5 from FIG. It is a schematic cross-sectional view when the gas supply device shown in FIG. 1A is cut from a direction different from that in FIG. 1A. FIG. 3 is another schematic cross-sectional view of the gas supply device shown in FIG. 1A. It is a graph which superposed the emission spectrum of the excimer lamp containing the luminescent gas containing Xe, and _{the absorption spectrum of oxygen (O 2).} It is sectional drawing which shows the simulation model structure of Example 1. FIG. It is a graph which shows the simulation result. It is a graph which shows the simulation result. It is a graph which shows the simulation result. It is a graph which shows the simulation result. It is sectional drawing which shows typically another configuration example of 1st Embodiment of a gas supply apparatus. It is sectional drawing which shows typically the structural example of the 2nd Embodiment of a gas supply apparatus. It is an enlarged view of the vicinity of the narrow portion 17 in FIG. It is sectional drawing which shows the simulation model structure of Example 2. FIG. It is a graph which shows the simulation result. It is a graph which shows the simulation result. It is a graph which shows the simulation result. It is sectional drawing which shows typically another configuration example of the 2nd Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of the 2nd Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of the 2nd Embodiment of a gas supply apparatus. It is a partial cross-sectional view which shows typically another configuration example of the 2nd Embodiment of a gas supply apparatus. It is a partial cross-sectional view which shows typically another configuration example of the 2nd Embodiment of a gas supply apparatus. It is a partial cross-sectional view which shows typically another configuration example of the 2nd Embodiment of a gas supply apparatus. It is sectional drawing which shows typically the structural example of the 3rd Embodiment of a gas supply apparatus. It is a schematic plan view of the light source provided in the 3rd Embodiment of a gas supply device. It is another schematic plan view of the light source provided in the 3rd Embodiment of a gas supply device. It is sectional drawing which shows typically the structural example of the 4th Embodiment of a gas supply apparatus. It is a schematic cross-sectional view when the structural example of the 4th Embodiment of a gas supply device is cut from the direction different from FIG. It is a graph which shows the simulation result. It is sectional drawing which shows typically the structural example of the 5th Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of 5th Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of 5th Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of 5th Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of 5th Embodiment of a gas supply apparatus. It is sectional drawing which shows typically the structural example of the 6th Embodiment of a gas supply apparatus. It is sectional drawing which shows typically the structural example of another embodiment of a gas supply apparatus.

[First Embodiment]
The first embodiment of the gas supply device according to the present invention will be described below.

"Construction"
FIG. 1A is a cross-sectional view schematically showing a configuration example of the gas supply device of the present embodiment. In the gas supply device 1 shown in FIG. 1A, a tubular housing 3, a light source 5 arranged in the housing 3, and a first gas flow into which a first gas G1 to cause a photochemical reaction flows. An inlet 11 and a first gas passage 8 through which the first gas G1 passes are provided.

Further, the gas supply device 1 includes a second gas inflow port 12 into which the second gas G2, which is a gas different from the first gas G1, flows in, and a second gas flow path 9 through which the second gas G2 passes. And a gas outlet 13 for flowing out the mixed gas G3, which is a mixture of the first gas G1 and the second gas G2, to the outside of the apparatus. The first gas G1 and the second gas G2 are mixed in the gas mixing unit 14.

The first gas G1 is a gas containing oxygen as a radical source. As an example, the first gas G1 is a mixed gas containing oxygen (for example, a mixed gas of oxygen and nitrogen) or air. The second gas G2 is a gas having a lower oxygen concentration than the first gas G1. As an example, the second gas G2 is _{an inert gas such as N 2} , Ar, or Ne, a gas in which a plurality of types of inert gases are mixed, or a mixed gas in which the inert gas contains a low concentration of oxygen.

The gas supply device 1 irradiates the first gas G1 flowing through the first gas passage 8 with ultraviolet light L1 emitted from the light source 5 and serves as a radical source contained in the first gas G1. Causes a photochemical reaction with the raw material. As a result, the first gas G1 is guided to the gas outlet 13 in a state of containing radicals, and is discharged from the gas outlet 13. As shown in FIG. 1A, an object 40 to be treated is placed on the outside of the gas supply device 1, and a gas containing radicals is sprayed on the surface of the object 40 to perform a predetermined treatment.

In the gas supply device 1 of the present embodiment, a second gas passage 9 through which the second gas G2 passes is provided outside the first gas passage 8 through which the first gas G1 passes. FIG. 1B is a drawing in which the light source 5 is not shown from FIG. 1A for convenience of explanation.

As shown in FIG. 1B, the housing 3 included in the gas supply device 1 has a first wall body 3a forming a first space 15 inside and a first wall body 3a outside the first wall body 3a. It has a second wall body 3b that forms a second space 16 between them. As shown in FIGS. 1A and 1B, the light source 5 and the first gas passage 8 are located in the first space 15, and the second gas passage 9 is located in the second space 16. ing.

The light source 5 has a light emitting surface 5a that emits ultraviolet light L1 toward the first gas passage 8. In the present embodiment, the light emitting surface 5a is formed along the shape of the first gas flow path 8, that is, along the first direction d1 which is the flow direction of the first gas G1. That is, the first direction d1 is the direction from the first gas inflow port 11 to the gas outflow port 13.

In this embodiment, an excimer lamp is adopted as an example of the light source 5. An example of the structure in this case will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view of the gas supply device 1 shown in FIG. 1A when it is cut in a plane orthogonal to the first direction d1. On the other hand, FIG. 1A corresponds to a schematic cross-sectional view when the gas supply device 1 is cut in a plane parallel to the first direction d1.

As shown in FIG. 2, the light source 5 arranged inside the housing 3 has a light emitting tube 21 extending along the first direction d1. More specifically, the arc tube 21 has a cylindrical shape and is arranged coaxially with the outer tube 21a located on the outside and the outer tube 21a inside the outer tube 21a, and has a smaller inner diameter than the outer tube 21a. It has an inner tube 21b having a cylindrical shape. Each arc tube 21 (21a, 21b) is made of a dielectric such as synthetic quartz glass.

A hollow tubular space is formed through the inner pipe 21b along the pipe axis direction, and this tubular space constitutes the first gas passage passage 8.

Both the outer tube 21a and the inner tube 21b are sealed at the end portion related to the first direction d1 (not shown), and both have an annular shape when viewed from the first direction d1. A light emitting space is formed. In this light emitting space, a light emitting gas 23G that forms excimer molecules by electric discharge is enclosed.

The wavelength of the ultraviolet light L1 emitted from the arc tube 21 is determined by the material of the luminescent gas 23G. In other words, the material of the luminescent gas 23G is appropriately selected according to the wavelength desired to be obtained as the ultraviolet light L1. The luminescent gas 23G can be, for example, a gas containing at least one material belonging to the group consisting of Xe, Ar, Kr, ArBr, ArF, KrCl, and KrBr. When the luminescent gas 23G is realized by these materials, the main luminescent wavelength of the ultraviolet light L1 is less than 230 nm.

The light source 5 illustrated in FIG. 2 has a first electrode 31 arranged on the outer wall surface of the outer tube 21a and a second electrode 32 arranged on the inner wall surface of the inner tube 21b. As an example, the first electrode 31 has a film shape, and the second electrode 32 has a mesh shape or a line shape. The first electrode 31 may also have a mesh shape or a linear shape as in the second electrode 32. Feed lines (not shown) are connected to these electrodes (31, 32).

In the light source 5 composed of an excimer lamp, when a high-frequency AC voltage of, for example, about 50 kHz to 5 MHz is applied between the first electrode 31 and the second electrode 32 from a lighting power source (not shown) via a feeder line. The voltage is applied to the light emitting gas 23G via the light emitting tube 21. At this time, a discharge plasma is generated in the discharge space filled with the luminescent gas 23G, an atom of the luminescent gas 23G is excited to enter an excimer state, and when this atom shifts to the ground state, excimer emission is generated. When the above-mentioned gas containing xenon (Xe) is used as the luminescent gas 23G, this excimer luminescence becomes ultraviolet light L1 having a peak wavelength in the vicinity of 172 nm.

The inner tube 21b of the arc tube 21 is formed with a second electrode 32 having a mesh shape or a linear shape as described above. Therefore, there is a gap in the second electrode 32, and the ultraviolet light L1 irradiates the hollow tubular space formed inside the arc tube 21 through this gap, that is, toward the first gas flow path 8. Will be done.

That is, the light source 5 has a light emitting surface 5a (see FIG. 1A) formed by the inner surface of the inner tube 21b extending along the first direction d1.

As shown in FIG. 3, the first electrode 31 has a mesh shape or a line shape, and a reflective member 33 that reflects ultraviolet light L1 is provided between the first electrode 31 and the housing 3 (first wall body 3a). It may be prepared. More specifically, the reflection member 33 may be provided on the surface of the first wall body 3a on the light source 5 side. The reflective member 33 is made of a material that exhibits a high reflectance (for example, 80% or more) with respect to ultraviolet light L1, and for example, Al, Al alloy, stainless steel, silica, silica alumina, or the like can be used.

Further, when the first wall body 3a itself is made of a material (for example, stainless steel such as SUS) that exhibits reflectance to ultraviolet light L1, the surface of the first wall body 3a can be used as the reflecting member 33. can.

FIG. 4 is a graph in which the emission spectrum of the light source 5 configured by the excimer lamp in which the emission gas 23G containing Xe is enclosed and _{the absorption spectrum of oxygen (O 2} ) are superimposed and displayed. In FIG. 4, the horizontal axis represents the wavelength, the left vertical axis represents the relative value of the light intensity of the excimer lamp, and the right vertical axis represents the absorption coefficient of _{oxygen (O 2).}

When a gas containing Xe is used as the emission gas 23G of the excimer lamp, as shown in FIG. 4, the ultraviolet light L1 emitted from the light source 5 has a main emission wavelength of 172 nm and is within a range of about 160 nm or more and 190 nm or less. Has a band in.

When the first gas G1 is a gas _{containing oxygen (O 2} ), the ultraviolet light L1 having a wavelength λ emitted from the light source 5 is irradiated to the first gas G1 and absorbed by _{oxygen (O 2).} Then, the reactions of the following equations (2) and (3) proceed. In equation (2), O ( ¹ D) is an excited O atom and exhibits extremely high reactivity. O ( ³ P) is an O atom in the ground state. The reaction of equations (2) and (3) occurs depending on the wavelength component of the ultraviolet light L1.
O ₂ + hν (λ) → O ( ¹ D) + O ( ³ P) ‥‥ (2)
O ₂ + hν (λ) → O ( ³ P) + O ( ³ P) ‥‥ (3)

That is, when the first gas G1 is irradiated with ultraviolet light L1, ^{radicals such as O (1} D) and O ( ³ P) are generated and contained in the first gas G1. In particular, in the gas supply device 1 of the present embodiment, since the light emitting surface 5a of the light source 5 extends along the first direction d1, the first gas G1 is the first gas passage toward the gas outlet 13. Ultraviolet light L1 continues to be irradiated while passing through the inside of 8. As a result, photochemical reactions occur one after another with respect to the unreacted radical source contained in the first gas G1, and the first gas G1 proceeds to the gas mixing unit 14 in a state of containing a high concentration of radicals. ..

On the other hand, in the second gas passage 9 different from the first gas passage 8, the second gas G2 flowing in from the second gas inflow port 12 is sent in the first direction d1 in the same manner as the first gas G1. To flow to. The second gas G2 has a lower oxygen concentration than the first gas G1 and is preferably an inert gas. In the gas supply device 1 of the present embodiment, the second gas G2 is a part of the second wall body 3b of the housing 3 after flowing through the second gas passage 9 along the first direction d1. It collides with the inner wall surface 3b1. After that, the traveling direction of the second gas G2 is changed and the second gas G2 is guided to the gas mixing unit 14.

In the gas mixing unit 14, the first gas G1 containing radicals and the second gas G2 having an oxygen concentration lower than that of the first gas G1 are mixed. In the gas supply device 1 of the present embodiment, the first gas G1 traveling in the first direction d1 and the second gas G2 traveling in a direction substantially orthogonal to the first direction d1 are mixed with each other. 14 is mixed. The mixed gas G3, which is a mixture of the first gas G1 and the second gas G2, flows out from the gas outlet 13 toward the object 40.

That is, according to the gas supply device 1 of the present embodiment, in the gas mixing section 14 located on the front side (upstream side) of the gas outlet 13, the first gas G1 containing oxygen radicals is the first gas. As a result of being mixed with the second gas G2 having an oxygen concentration lower than that of G1, the oxygen concentration contained in the gas decreases. As a result, the rate at which highly active oxygen radicals react with oxygen slows down, so that the mixed gas G3 in a state containing a large amount of radicals can be blown onto the object 40 from the gas outlet 13.

"inspection"
According to the gas supply device 1 of the present embodiment, the point that the gas discharged from the gas outlet 13 (mixed gas G3) contains a high concentration of radicals was verified by simulation.

FIG. 5 is a cross-sectional view schematically showing a model of the gas supply device used in this simulation.

The gas supply device 1 used in the simulation is a light source 5 having a light emitting surface 5a having a side shape of a tubular body having a length h1 of 50 mm in the first direction d1, and a region surrounded by the light emitting surface 5a. A first gas passage 8 formed in the above and a second gas passage 9 formed outside the first gas passage 8 were provided. The light source 5 was an Xe excimer lamp having a main peak wavelength of 172 nm.

The gas supply device 1 is located outside so as to surround the first gas inlet 11 having a diameter of 5 mm and the first gas inlet 11 connected to the first gas passage 8, and the second gas. It was provided with an annular second gas inflow port 12 having a diameter of 9 mm, which was connected to the flow path 9. Further, the gas supply device 1 is provided with a circular gas outlet 13 having a diameter of 5 mm at a position separated from the first gas inlet 11 and the second gas inlet 12 in the first direction d1.

More specifically, the gas outlet 13 is provided on the downstream side of the gas mixing section 14 where the first gas passage 8 and the second gas passage 9 are connected to each other, and is provided with the object 40. The separation distance v1 was set to 9 mm. Further, the second gas passage 9 was communicated with the first gas passage 8 at a position upstream of the gas outlet 13 by a distance v2. This distance v2 was set to 1 mm.

In the gas supply device 1 of the simulation model, the first gas inlet 11 and the second gas inlet 11 and the second gas inlet 11 and the second gas inlet 11 and the second gas inlet 11 and the second gas inlet 11 and the second gas inflow port 8 are irradiated with ultraviolet light L1 from the light source 5 at an illuminance of 50 mW / cm ^{2 on the light emitting surface 5a.} The concentration of radicals on the surface of the object 40 was measured when a predetermined flow rate of gas was flowed in from the gas inlet 12. More specifically, the calculation was performed under the following simulation conditions.

The first gas passage 8, the light source 5, and the second gas passage 9 all have an axisymmetric structure, and the light emitting surface 5a of the light source 5 surrounds the first gas passage 8. Is arranged, and the structure is such that the second gas passage 9 is arranged so as to surround the light source 5. The object 40 had a circular shape with a radius r1 (see FIG. 5) having a center arranged on the central axis of the first gas passage 8 and having a radius r1 (see FIG. 5).

(Example 1) The first gas G1 composed of a mixed gas of 80% nitrogen gas and 20% oxygen gas is introduced into the gas supply device 1 from the first gas inflow port 11 at a flow rate of 15 L / min, and at the same time. The second gas G2 composed of 100% nitrogen gas was introduced into the gas supply device 1 from the second gas inflow port 12 at a flow rate of 35 L / min.

(Reference Example 1) The first gas G1 composed of a mixed gas of 80% nitrogen gas and 20% oxygen gas was introduced into the gas supply device 1 from the first gas inflow port 11 at a flow rate of 15 L / min. However, as compared with the first embodiment, the second gas G2 is not introduced in the gas supply device 1.

For both Example 1 and Reference Example 1, in a region within a radius of 2.5 mm (φ5 mm) from the center of the surface of the object 40 arranged to face the gas outlet 13 of the gas supply device 1. The average concentration of ^{oxygen radical O (3} P) contained in the injected gas was calculated. In the case of the first embodiment, the "gas" here corresponds to a mixed gas G3 in which the first gas G1 and the second gas G2 after being irradiated with the ultraviolet light L1 are mixed. In the case of Reference Example 1, it corresponds to the first gas G1 after being irradiated with ultraviolet light L1.

(result)
The calculation result under the above simulation conditions is shown in FIG. 6A. ^{According to FIG. 6A, the average concentration of oxygen radical O (3} P) contained in the gas sprayed on the surface of the object 40 is increased four times or more in Example 1 as compared with Reference Example 1. It was confirmed that.

From this result, according to Example 1, the second gas G2 having a low oxygen concentration is mixed with the first gas G1 at a position in front of the gas outlet 13, so that the reaction speed according to the above-mentioned equation (1) is obtained. ^{It is considered that the decrease in the concentration of O (3} P) due to the reaction of the formula (1) can be suppressed by the time when the concentration decreases and reaches the surface of the object 40.

The result of performing the same simulation using the first gas G1 as a mixed gas of 99.5% nitrogen gas and 0.5% oxygen gas is shown in FIG. 6B. ^{According to FIG. 6B, the average concentration of oxygen radicals O (3} P) contained in the mixed gas G3 sprayed on the surface of the object 40 is 15 times or more (about 16 times) in Example 1 as compared with Reference Example 1. It was confirmed that the increase was large (up to double).

Next, in Example 1, the same simulation was performed by changing the flow rate ratio of the first gas G1 and the second gas G2. The results are shown in FIGS. 7A and 7B. FIG. 7A shows a flow rate of the first gas G1 of 15 L / min when the first gas G1 is a mixed gas of 80% nitrogen gas and 20% oxygen gas, as in Example 1 shown in FIG. 6A. It is a graph which shows the change of the average concentration ^{of oxygen radical O (3} P) on the surface of an object 40 when it fixed with and made the flow rate of the 2nd gas G2 different. FIG. 7B shows the flow rate of the first gas G1 when the first gas G1 is a mixed gas of 99.5% nitrogen gas and 0.5% oxygen gas, as in Example 1 shown in FIG. 6B. Is a graph showing the change in the average concentration ^{of oxygen radical O (3} P) on the surface of the object 40 when the flow rate of the second gas G2 is changed by fixing the gas at 15 L / min. In any of the drawings, for example, the flow rate ratio of the first gas G1 and the second gas G2 is 1: 3, which is indicated by the notation "G1: G2 = 1: 3". The same applies to other flow rate ratios.

According to FIGS. 7A and 7B, regardless of whether the oxygen concentration contained in the first gas G1 is 20% or 0.5%, as the flow rate of the second gas G2 is increased, the object 40 It can be seen that the average concentration of oxygen radical O ( ^{3 P) on the surface is increasing.} In particular, as shown in FIG. 7A, when the oxygen concentration contained in the first gas G1 is relatively higher than that in the case of FIG. 7B, the second gas G2 is mixed at a flow rate twice or more that of the first gas G1. ^{It was confirmed that the average concentration of oxygen radical O (3} P) on the surface of the object 40 can be greatly increased by allowing the mixture.

<< Another configuration example >>
Hereinafter, another configuration example of the present embodiment will be described.

<1> As described above with reference to FIGS. 2 and 3, the gas supply device 1 has been described as including a light source 5 having a circular shape when viewed from the first direction d1. However, the shape of the light source 5 is not limited to this. The same applies to the gas supply device 1 of the second embodiment described later.

For example, as shown in FIG. 8, the gas supply device 1 may include a light source 5 having a rectangular annular arc tube 21. In this case, the first gas passage 8 formed by the inside of the inner pipe 21b also has a rectangular shape when viewed from the first direction d1. Further, the second gas passage 9 formed on the outside of the first gas passage 8 exhibits a rectangular ring shape when viewed from the first direction d1.

<2> In the above embodiment, the housing 3 included in the gas supply device 1 is described as having a first wall body 3a exhibiting a partition function between the second gas passage 9 and the light source 5. However, the second gas passage 9 may be formed on the outside of the arc tube 21 constituting the light source 5 without the first wall 3a. Also in this case, as described above with reference to FIG. 3, it is preferable to provide the reflecting member 33 that reflects the ultraviolet light L1 on the outer surface of the arc tube 21. As a result, the ultraviolet light L1 traveling to the second gas passage 9 side is returned to the first gas passage 8 side, and the irradiation dose of the ultraviolet light L1 irradiated to the first gas G1 is increased.

<3> In the above embodiment, it has been described that the traveling directions of the first gas G1 and the second gas G2 flowing into the gas mixing unit 14 are substantially orthogonal to each other, but the present invention is not limited to this. However, from the viewpoint of enhancing the effect of mixing the second gas G2 having a low oxygen concentration with the first gas G1 in the gas mixing unit 14, the relationship in which the traveling directions of the two are substantially orthogonal to each other, that is, the angle between the two is large. It is preferably 70 ° to 110 °, more preferably 80 ° to 100 °.

[Second Embodiment]
The second embodiment of the gas supply device according to the present invention will be described focusing on the parts different from the first embodiment.

"Construction"
FIG. 9 is a cross-sectional view schematically showing a configuration example of the gas supply device of the present embodiment. In this embodiment, as compared with the first embodiment, the first gas passage 8 flows on the gas mixing portion 14 side as compared with the position closer to the first gas inlet 11 (that is, on the upstream side). It has a flow region (hereinafter referred to as "narrow portion 17") having a small road cross-sectional area. FIG. 10 is an enlarged view of the vicinity of the narrow portion 17 in FIG.

Similar to the first embodiment, while the first gas G1 is flowing through the first gas passage 8, a photochemical reaction occurs due to irradiation with ultraviolet light L1, and the first gas G1 has a high radical content. It proceeds to the region where the narrow portion 17 is formed while being contained in the concentration.

The first gas G1 that has reached the narrow portion 17 has a high flow velocity when flowing through the narrow portion 17 having a small flow path cross-sectional area, and is discharged from the gas outlet 13 via the gas mixing portion 14.

That is, according to the above configuration, since the flow path cross-sectional area in the first gas passage 8 is large on the upstream side of the narrow portion 17, that is, on the first gas inflow port 11 side, the passage passes through the narrow portion 17. The first gas G1 flows through the first gas passage 8 at a flow velocity slower than the time point. Therefore, the time during which the ultraviolet light L1 from the light source 5 is irradiated to the first gas G1 is secured for a long time, and a sufficient amount of irradiation light is secured to generate radicals by the photochemical reaction.

After that, the first gas G1 is mixed with the second gas G2 while increasing the flow velocity when flowing through the narrow portion 17, and then discharged to the outside through the gas outlet 13. As a result, the time required to reach the surface of the object 40 is shortened, and the reduction of radicals due to the reaction of the above-mentioned equation (1) can be further suppressed.

In the gas supply device 1 shown in FIGS. 9 and 10, since the light emitting surface 5a of the light source 5 extends along the first direction d1, the first gas G1 is located near the narrow portion 17. The ultraviolet light L1 from the light source 5 is irradiated until it reaches the point. Therefore, the first gas G1 that has reached a portion near the narrow portion 17 is in a state of containing radicals at a high concentration.

Further, in the gas supply device 1 shown in FIGS. 9 and 10, the position of the end of the light emitting surface 5a of the light source 5 on the gas outlet 13 side (gas mixing portion 14 side) in the first direction d1 and the narrow portion 17 The positions of the ends on the side of the first gas inflow port 11 in the first direction d1 are substantially the same. That is, the light emitting surface 5a and the narrow portion 17 are continuously arranged with respect to the first direction d1. According to this configuration, the first gas G1 is irradiated with ultraviolet light L1 until just before the flow velocity of the first gas G1 increases, so that the concentration of radicals contained in the first gas G1 that has reached the narrow portion 17 is increased. It will be further enhanced.

"inspection"
According to the gas supply device 1 of the present embodiment, a simulation similar to that of the first embodiment is performed in that a higher concentration of radicals is contained in the gas (mixed gas G3) discharged from the gas outlet 13. Verified by.

FIG. 11 is a cross-sectional view schematically showing a model of the gas supply device used in this simulation, and corresponds to the second embodiment. The gas supply device 1 of the second embodiment is different from the gas supply device 1 of the first embodiment described above in the first embodiment in that it includes a narrow portion 17. That is, the first gas passage 8 includes a region where the inner diameter of the tubular body is uniform, and a narrow portion 17 whose inner diameter decreases as it approaches the gas mixing portion 14.

More details are as follows. The gas supply device 1 of the second embodiment includes a circular first gas inlet 11 having a diameter of 5 mm and a circular gas outlet 13 having a diameter of 2.5 mm. The end of the narrow portion 17 on the first gas inflow port 11 side showed the same circular shape with a diameter of 5 mm as the first gas inflow port 11. The end of the narrow portion 17 on the gas outlet 13 side showed the same circular shape with a diameter of 2.5 mm as the gas outlet 13.

The length h2 of the first gas passage 8 in the region on the first gas inflow port 11 side of the narrow portion 17 in the first direction d1 is 40 mm, and the length h2 of the region constituting the narrow portion 17 is the first direction d1. The length h3 according to the above was 10 mm. That is, in the gas supply device 1 of the second embodiment, the length of the first gas passage 8 in the first direction d1 was 50 mm, which is the same as that of the gas supply device 1 of the first embodiment.

In the gas mixing section 14, the end of the narrow portion 17 on the gas outlet 13 side is connected to the second gas passage 9 and the first gas G1 and the second gas G2 are connected to each other in the gas mixing section 14. The mixed gas G3 obtained by mixing was discharged from the gas outlet 13 having a circular shape having a diameter of 2.5 mm.

(Example 2) Similar to Example 1, the first gas G1 composed of a mixed gas of 80% nitrogen gas and 20% oxygen gas is carried out from the first gas inlet 11 at a flow rate of 15 L / min. In addition to being introduced into the gas supply device 1 in the embodiment, the second gas G2 made of 100% nitrogen gas was introduced into the gas supply device 1 from the second gas inflow port 12 at a flow rate of 35 L / min.

(Reference Example 2) Similar to Reference Example 1, the first gas G1 composed of a mixed gas of 80% nitrogen gas and 20% oxygen gas is supplied from the first gas inlet 11 at a flow rate of 15 L / min. Introduced in 1. However, as compared with Example 2, the second gas G2 is not introduced in the gas supply device 1.

For both the second embodiment and the second reference example, in a region within a radius of 2.5 mm (φ5 mm) from the center of the surface of the object 40 arranged to face the gas outlet 13 of the gas supply device 1. The average concentration of ^{oxygen radical O (3} P) contained in the injected gas was calculated. In the case of the second embodiment, the "gas" here corresponds to a mixed gas G3 in which the first gas G1 and the second gas G2 after being irradiated with the ultraviolet light L1 are mixed. In the case of Reference Example 2, it corresponds to the first gas G1 after being irradiated with ultraviolet light L1.

(result)
The calculation results under the above simulation conditions are shown in FIGS. 12A and 12B. FIG. 12A is a drawing graphed by relative values based on the value of the average concentration of oxygen radical O ( ^{3 P) in Comparative Example 2.} Further, FIG. 12B is a drawing graphed by a relative value based on the value of the average concentration ^{of the oxygen radical O (3} P) in Reference Example 1 shown in FIG. 6A. ^{According to FIG. 12A, in Example 2, the average concentration of oxygen radicals O (3} P) contained in the gas sprayed on the surface of the object 40 increased by 1,000 times or more more than in Reference Example 2. It was confirmed that Further, as shown in FIG. 12B, as compared with the result of Reference Example 1, according to Example 2, the average concentration of ^{oxygen radicals O (3 P) contained in the gas sprayed on the surface of the object 40 is 1.} It was confirmed that the increase was more than 500 times.

From the above simulation results, according to the gas supply device 1 of the second embodiment, the gas flow is caused by providing the narrow portion 17 on the gas outlet 13 side (gas mixing portion 14 side) of the first gas passage 8. As a result of increasing the flow velocity of the mixed gas G3 flowing out from the outlet 13, ^{the ratio of oxygen radicals (O (3} P)) contained in the mixed gas G3 reaching the surface of the object 40 before being deactivated is increased. It is thought that it was. Further, as in the first embodiment, the second gas G2 having a low oxygen concentration is mixed with the first gas G1 in the gas mixing section 14 located in front of the gas outlet 13, thereby causing the above-mentioned (1). It is considered that the decrease in the concentration of ^{O (3} P) due to the reaction in the formula (1) can be suppressed by the time when the reaction speed according to the formula decreases and the surface of the object 40 is reached.

Next, in Example 2, the same simulation was performed by changing the flow rate ratio of the first gas G1 and the second gas G2. The result is shown in FIG. FIG. 13 shows that, as in Example 2 shown in FIG. 12, when the first gas G1 is a mixed gas of 80% nitrogen gas and 20% oxygen gas, the flow rate of the first gas G1 is 15 L / min. It is a graph which shows the change of the average concentration ^{of oxygen radical O (3} P) on the surface of an object 40 when it fixed with and made the flow rate of the 2nd gas G2 different.

According to FIG. 13, according to the gas supply device 1 of the present embodiment, as in the first embodiment, the oxygen radical O ( ³ P) on the surface of the object 40 increases as the flow rate of the second gas G2 increases. It can be seen that the average concentration of) is increasing.

<< Another configuration example >>
Hereinafter, another configuration example of the present embodiment will be described.

<1> As shown in FIG. 14, a reflecting surface 17a showing reflectivity to ultraviolet light L1 may be provided at a position related to the inner surface of the narrow portion 17.

Similar to the gas supply device 1 shown in FIG. 9, the gas supply device 1 shown in FIG. 14 has a light emitting surface 5a formed along the first direction d1. Since the ultraviolet light L1 emitted from the light emitting surface 5a travels toward the first gas passage 8 side with a predetermined divergence angle, a part of ultraviolet light is emitted from the light emitting surface 5a at a position close to the narrow portion 17. It is assumed that the light L1 travels toward the narrow portion 17. In such a case, by forming the reflecting surface 17a on the inner surface of the narrow portion 17 as shown in FIG. 14, the ultraviolet light L1 reflected by the reflecting surface 17a can be returned to the upstream side of the narrow portion 17. .. As a result, the amount of ultraviolet light L1 irradiated to the first gas G1 increases, so that the effect of further increasing the concentration of radicals contained in the mixed gas G3 can be obtained.

The reflecting surface 17a is realized by forming a film (layer) made of a material highly reflective to ultraviolet light L1 such as silica particles and silica alumina particles on the inner surface of the narrow portion 17, for example. Further, when the housing 3 itself is made of a material such as stainless steel (SUS) that exhibits a certain ratio of reflectance to ultraviolet light L1, the housing 3 itself at the position where the narrow portion 17 is formed ( It may be assumed that the reflecting surface 17a is realized by the first wall body 3a).

<2> As shown in FIG. 15, the light emitting surface 5a may extend to the region forming the narrow portion 17. In the gas supply device 1 shown in FIG. 15, by widening the shape of the light source 5 at a position close to the gas outlet 13, the first gas passage is performed at a position close to the gas outlet 13 (a position close to the gas mixing portion 14). A narrow portion 17 having a small flow path cross-sectional area of the flow path 8 is formed.

In the case of such a configuration, since the flow velocity of the first gas G1 flowing through the narrow portion 17 is increased, the irradiation light amount of the ultraviolet light L1 is lower than that on the upstream side of the narrow portion 17. However, at a position upstream of the narrow portion 17, the first gas G1 has already been irradiated with ultraviolet light L1 having an irradiation light amount required for generating radicals, and therefore, when it reaches the narrow portion 17, it reaches the narrow portion 17. It contains a lot of radicals. Compared with the structure shown in FIG. 9, the structure shown in FIG. 15 further adds radicals to the gas flowing through the narrow portion 17 by irradiating the gas passing through the narrow portion 17 with ultraviolet light L1 even though the amount of irradiation light is small. It has the effect of being able to be produced, and the radical generation ability is not lower than that of the structure shown in FIG.

From the same viewpoint, as in the gas supply device 1 shown in FIG. 16, a translucent member 17b exhibiting transparency to the ultraviolet light L1 is arranged on the light emitting surface 5a at a position close to the gas outlet 13. The narrow portion 17 may be formed by the region surrounded by the translucent member 17b. In this case, the translucent member 17b has a hollow tubular shape penetrating with respect to the first direction d1, and the opening area of this tubular body is closer to the gas outlet 13 side than the first gas inlet 11 side (gas mixing portion 14). The side) is smaller. Even in this case, the first gas G1 passing through the narrow portion 17 formed by the inside of the translucent member 17b is discharged to the outside through the gas mixing portion 14 and the gas outlet 13 while increasing the flow velocity during flow. Will be done. Further, even when passing through the narrow portion 17, the ultraviolet light L1 emitted from the light emitting surface 5a passes through the light transmitting member 17b and is irradiated to the first gas G1. Therefore, the structure shown in FIG. As in the case of, the effect is that more radicals can be generated as compared with the structure shown in FIG.

Such a translucent member 17b is made of, for example, a material such as quartz or magnesium fluoride. In such a case, the light transmitting member 17b may be welded to the light emitting tube 21 constituting the light source 5, or may be physically fitted and attached.

<3> In the gas supply device 1 shown in FIG. 9, the narrow portion 17 has a shape in which the cross-sectional area of the flow path continuously decreases as it approaches the gas outlet 13 (gas mixing portion 14). However, as long as the narrow portion 17 has a shape in the first gas flow path 8 whose channel cross-sectional area is smaller than the position on the upstream side (first gas inflow port 11 side) of the narrow portion 17. In, the shape is arbitrary. This point is the same in the gas supply device 1 shown in FIGS. 14 to 16.

For example, as shown in FIG. 17A, the gas supply device 1 may have a shape in which the cross-sectional area of the flow path is substantially constant in the narrow portion 17. Further, as shown in FIG. 17B, the gas supply device 1 may have a shape in which the cross-sectional area of the flow path is intermittently reduced in the narrow portion 17.

Further, as in the gas supply device 1 shown in FIG. 17C, the gas mixing unit 14 may have a shape in which the cross-sectional area of the flow path is intermittently reduced as it approaches the gas outlet 13. 17A to 17C are enlarged cross-sectional views of the vicinity of the gas outlet 13 in the gas supply device 1.

[Third Embodiment]
The third embodiment of the gas supply device according to the present invention will be described focusing on the parts different from the first embodiment.

"Construction"
FIG. 18 is a schematic cross-sectional view of the gas supply device 1 of the present embodiment cut along a plane orthogonal to the first direction d1, following FIG. The schematic cross-sectional view of the gas supply device 1 when cut in a plane parallel to the first direction d1 is the same as that in FIG. 1A.

In the first embodiment, it is assumed that the first gas passage 8 is formed inside the arc tube 21 constituting the light source 5. On the other hand, in the present embodiment, a plurality of light sources 5 (51, 52) are arranged apart from each other, and a first gas passage 8 is formed in a region sandwiched between the light sources 5 (51, 52). That is, the light emitting surfaces 5a included in the plurality of light sources 5 (51, 52) are arranged so as to face each other so as to sandwich the first gas passage path 8.

Since the other points are common to the first embodiment, the description is omitted from the viewpoint of avoiding duplication.

<< Another configuration example >>
Hereinafter, another configuration example of the present embodiment will be described.

<1> In the first embodiment, the first gas passage 8 is formed in the hollow region of the light source 5 having a tubular shape. Therefore, it is assumed that the light source 5 includes a light emitting tube 21 having a double tube structure. However, the shape of the light source 5 is not limited in the configuration in which the gas supply device 1 includes a plurality of light sources 5 as in the present embodiment.

For example, FIG. 19A is a schematic cross-sectional view when an excimer lamp exhibiting a so-called "single tube structure" is adopted as the light source 5 and cut in a plane orthogonal to the first direction d1. The light source 5 shown in FIG. 19A has one arc tube 21 unlike the light source 5 shown in FIG. The arc tube 21 is sealed at the end portion related to the longitudinal direction, that is, the first direction d1 (not shown), and the luminescent gas 23G is sealed in the inner space. A second electrode 32 is arranged inside (inside) the arc tube 21, and a mesh-shaped or linear first electrode 31 is arranged on the outer wall surface of the arc tube 21.

As another example, FIG. 19B is a cross-sectional view schematically illustrated according to FIG. 19A when an excimer lamp exhibiting a so-called "flat tube structure" is adopted as the light source 5. The light source 5 shown in FIG. 13B has one arc tube 21 that has a rectangular shape when viewed from the longitudinal direction, that is, the first direction d1. A first electrode 31 is arranged on one outer surface of the arc tube 21, and a second electrode 32 is arranged on the outer surface of the arc tube 21 at a position facing the first electrode 31. Of the first electrode 31 and the second electrode 32, the electrodes located at least on the first gas passage 8 side have a mesh shape (so as not to prevent the ultraviolet light L1 from being emitted to the outside of the arc tube 21). It has a mesh shape) or a linear shape.

Also in the light source 5 shown in FIGS. 19A and 19B, the shape when cut in a plane orthogonal to the first direction d1 is not limited to a circle or a rectangle, and various shapes can be adopted.

<2> In the present embodiment, the light source 5 included in the gas supply device 1 is not limited to the excimer lamp. That is, the light source 5 may be a surface light source that emits ultraviolet light L1 and extends along the first direction d1, and may be configured by, for example, a surface light source in which ultraviolet LED elements are arranged in the surface direction. ..

<3> In the present embodiment as well, the first gas flow path 8 may include the narrow portion 17 as in the second embodiment.

[Fourth Embodiment]
The fourth embodiment of the gas supply device according to the present invention will be described focusing on the parts different from each of the above embodiments.

"Construction"
FIG. 20 is a schematic cross-sectional view of the gas supply device 1 of the present embodiment cut along a plane parallel to the first direction d1, following FIG. Further, FIG. 21 is a schematic cross-sectional view of the gas supply device 1 shown in FIG. 20 when the gas supply device 1 is cut in a plane orthogonal to the first direction d1.

In each of the above embodiments, the first gas passage 8 is formed in the region surrounded by the light emitting surface 5a. On the other hand, the present embodiment is different in that the first gas passage 8 is formed between the light emitting surface 5a and the wall body (first wall body 3a) constituting the housing 3. A second gas passage 9 through which the second gas G2 passes is provided outside the first gas passage 8, that is, between the first wall 3a and the second wall 3b. The points are common to each of the above-described embodiments.

That is, as shown in FIG. 21, the light source 5 arranged in the housing 3 is arranged so that the light emitting surface 5a is surrounded by the first wall body 3a which is the inner side surface of the housing 3. The first gas G1 passes through the first gas passage 8 formed outside the light source 5. In this case, the first electrode 31 has a mesh shape or a linear shape so as not to prevent the ultraviolet light L1 from being emitted to the outside of the arc tube 21.

Since the other points are common to the first embodiment, the description is omitted from the viewpoint of avoiding duplication.

<< Another configuration example >>
Hereinafter, another configuration example of the present embodiment will be described.

<1> Also in the present embodiment, as in the third embodiment, the light source 5 is not limited to the excimer lamp having a double tube structure, and may be an excimer lamp having a single tube structure or a flat tube structure. It may be composed of a plurality of arranged ultraviolet LED elements.

<2> In the present embodiment as well, the first gas flow path 8 may include the narrow portion 17 as in the second embodiment.

<3> In the present embodiment, the light source 5 may also have a light emitting surface 5a that emits ultraviolet light L1 formed at an end portion on the gas outlet 13 side. In this case, the ultraviolet light L1 is also irradiated to the first gas G1 existing in the gas mixing unit 14. In FIG. 22, in the light source 5, when the light emitting surface 5a was also formed at the end on the gas outlet 13 side (Example 3), the light emitting surface 5a was not formed at the end on the gas outlet 13 side. It is a simulation result comparing the average concentration ^{of O (3} P) on the surface of the object 40 in the case (Example 4) and the case where other conditions are shared. According to FIG. 22, the effect of improving the average concentration of more O ⁽³ P) than Example 4 towards the third embodiment is confirmed.

The simulation result shown in FIG. 22 was calculated under the following simulation conditions.
The first gas G1 was composed of a mixed gas of 99.5% nitrogen gas and 0.5% oxygen gas, and the flow rate was 15 L / min.
-The second gas G2 was composed of nitrogen gas and had a flow rate of 15 L / min.
The light source 5 was composed of a Xe excimer lamp having a diameter of 5 mm and a length of 50 mm in the first direction d1, and the illuminance on the light emitting surface 5a was 50 mW / cm ² .
The first gas passage 8 had an annular tubular body with a diameter of 10 mm located outside the light source 5, and had a length of 52.5 mm in the first direction d1.
The second gas passage 9 had an annular tubular body with a diameter of 14 mm located outside the first gas passage 8, and had a length of 55 mm in the first direction d1.
The gas outlet 13 has a circular shape with a diameter of 5 mm, and is smaller than the flow path cross-sectional area of the first gas flow path 8.
The distance between the end of the light source 5 in the first direction d1 and the gas outlet 13 was 5 mm.
The distance between the gas outlet 13 and the object 40 was 5 mm.

[Fifth Embodiment]
The fifth embodiment of the gas supply device according to the present invention will be described focusing on the parts different from each of the above-described embodiments.

"Construction"
FIG. 23 is a cross-sectional view schematically showing a configuration example of the gas supply device of the present embodiment. This embodiment is different from the first embodiment in that the longitudinal direction of the light source 5 is non-parallel to the gas flow path direction.

That is, the light source 5 has a long shape extending along the second direction d2 orthogonal to the first direction d1, and has a light emitting surface 5a extending along the second direction d2. .. The first gas inflow port 11 and the second gas inflow port 12 also extend along the second direction d2.

The first gas G1 flows in the direction of the first direction d1 from the first gas inflow port 11 formed so as to extend along the second direction d2, and the first gas G1 flows through the first gas passage. By irradiating the ultraviolet light L1 from the light emitting surface 5a while passing through the inside of 8, it becomes a gas containing radicals. Further, the second gas G2 flows in the direction of the first direction d1 from the second gas inflow port 12 formed so as to extend along the second direction d2, and the radical is discharged at the position on the gas outlet 13 side. It is mixed with the containing first gas G1 (gas mixing unit 14) and discharged as a mixed gas G3 from the gas outlet 13 toward the object 40.

Since the other points are common to the first embodiment, the description is omitted from the viewpoint of avoiding duplication.

FIG. 23 shows a case where the light source 5 has a rectangular shape when viewed from the second direction d2, and can be realized by an excimer lamp having a flat tube structure with the axial direction d2 in the second direction. Further, as shown in FIG. 24, the light source 5 may have a circular shape when viewed from the second direction d2. In this case, the light source 5 can be an excimer lamp having a double-tube structure or a single-tube structure with the axial direction d2 in the second direction.

As another example, as shown in FIGS. 25 and 26, a plurality of long light sources 5 having the second direction d2 as the longitudinal direction may be arranged in the first direction d1.

More specifically, the gas supply device 1 shown in FIG. 25 includes light sources 5 (51, 52, 53) arranged along the first direction d1, and all of these light emitting surfaces 5a are in the second direction d2. It is postponed. A first gas passage 8 is formed outside the light source 5.

Further, the gas supply device 1 shown in FIG. 26 has three light sources 5 arranged along the first direction d1 and three other light sources 5 arranged so as to face the light emitting surface 5a of these light sources 5. A light source 5 is provided, and the light emitting surface 5a of each light source 5 extends in the second direction d2. A first gas passage 8 is formed at a position sandwiched between the light emitting surfaces 5a facing each other.

<< Another configuration example >>
Hereinafter, another configuration example of the present embodiment will be described.

<1> As shown in FIG. 27, the second gas G2 may be introduced at a position on the gas outlet 13 side in the first gas passage 8. In this case, the gas mixing section 14 is formed in the first gas passage 8 at a position close to the gas outlet 13. Further, a part of the first gas passage 8 also serves as the second gas passage 9.

In the case of the example shown in FIG. 27, the second gas inlet 12 is provided so that the first gas G1 does not leak out of the apparatus from the second gas inlet 12 into which the second gas G2 is introduced. It may be connected to the gas supply source of the second gas G2 via a check valve (not shown).

<2> In the present embodiment as well, the first gas flow path 8 may include the narrow portion 17 as in the second embodiment.

[Sixth Embodiment]
The sixth embodiment of the gas supply device according to the present invention will be described focusing on the parts different from each of the above embodiments.

As shown in FIG. 28, the gas supply device 1 of the present embodiment is provided with a gas mixing unit 14 in which the first gas G1 and the second gas G2 are mixed between the gas outlet 13 and the object 40. Has been done. More specifically, the second gas G2 is supplied from the gas supply source 50 capable of supplying the second gas G2 to the gas outlet 13 and the object 40 via the second gas inlet 12. .. The first gas G1 containing a large amount of radicals flows out from the gas outlet 13 by being irradiated with ultraviolet light L1. As a result, the mixed gas G3, which is a mixture of the first gas G1 and the second gas G2 having a lower oxygen concentration than the first gas G1, is sprayed on the surface of the object 40.

Also in such an embodiment, it is possible to blow a gas containing a high concentration of radicals onto the surface of the object 40.

In addition, in this embodiment, as for the shape of the light source 5 and the first gas flow path 8, the above-described configuration can be appropriately adopted in each embodiment.

[Another Embodiment]
<1> As shown in FIG. 29, in an embodiment in which ultraviolet light L1 is emitted outward from the light source 5, a part of the region is used as the first gas passage 8 and the other region is used as the second gas flow. It may be the road 9. In such a case, the light source 5 may not be provided with the light emitting surface 5a on the second gas passage 9 side. Further, as another aspect, the light source 5 may have a reflection member 33 (see FIG. 3) for reflecting the ultraviolet light L1 on the first gas passage 8 side.

Even in such a case, the structure of the gas supply device 1 of each of the above-described embodiments can be appropriately applied.

<2> For example, in the gas supply device 1 of the first embodiment, the first gas passage 8 is set to the outside of the light source 5 by emitting ultraviolet light L1 toward the outside of the arc tube 21. The second gas passage 9 may be inside the light source 5. In other words, the first gas passage 8 through which the first gas G1 passes is arranged outside so as to surround or sandwich the second gas passage 9 through which the second gas G2 passes. It does not matter if it is present. The same applies to other embodiments.

<3> In addition, in each of the above-described embodiments, the gas supply device 1 may be realized by applying mutual configurations.

1: Gas supply device 3: Housing 3a: First wall body 3b: Second wall body 3b 1: Inner wall surface 5: Light source 5a: Light emitting surface 8: First gas flow path 9: Second gas flow path 11: 1st gas inflow port 12: 2nd gas inflow port 13: Gas outflow port 14: Gas mixing part 15: 1st space 16: 2nd space 17: Narrow part 17a: Reflective surface 17b: Translucent member 21: Light emitting tube 21a : Outer tube 21b: Inner tube 23G: Luminous gas 31: First electrode 32: Second electrode 33: Reflective member 40: Object 50: Gas supply source G1: First gas G2: Second gas G3: Mixed gas L1: Ultraviolet light d1: First direction d2: Second direction

Claims (14)

The first gas inlet, where the first gas containing oxygen, which is a radical source, flows in,
A second gas inlet, which is provided at a location different from the first gas inlet and into which a second gas having a lower oxygen concentration than the first gas flows in.
The first gas flow path through which the first gas flowing in from the first gas inflow port flows,
A light source that emits ultraviolet light toward the irradiation region in the first gas passage, and
A gas mixing section in which the first gas and the second gas are mixed after passing through at least a part of the irradiation region.
A gas supply device including a gas outlet that allows the mixed gas after being mixed in the gas mixing section to flow out to the outside. The first aspect of the invention, wherein the first gas is mixed with the second gas flowing in a direction substantially orthogonal to the flow path direction of the first gas. Gas supply device. A second gas flow path through which the second gas flowing in from the second gas inflow port flows is provided.
The gas supply device according to claim 1 or 2, wherein the second gas passage is connected to the gas mixing portion at a position closer to the gas outlet side than the irradiation region. The gas supply device according to claim 3, wherein the second gas passage is arranged outside so as to sandwich or surround the first gas passage. It has a housing with a built-in light source.
The light source has a light emitting tube in which a hollow tubular space is formed through the tube axis direction, and a light emitting surface formed along the space on the tubular space side of the light emitting tube.
The first gas passage is formed in the tubular space surrounded by the light emitting surface.
The gas supply device according to claim 4, wherein the second gas passage is formed in a region sandwiched between an outer wall of the arc tube and an inner wall of the housing. It has a housing in which the light source is built.
The housing is
A first wall body forming a first space in which the light source is arranged, and
It has a second wall body that is arranged outside the first wall body and forms a second space with the first wall body.
The light source has a light emitting tube formed along the tube axis direction and a light emitting surface formed along the outer surface of the light emitting tube.
The first gas passage is formed in a region sandwiched between the outer wall of the arc tube and the first wall body.
The gas supply device according to claim 4, wherein the second gas passage is formed in a region sandwiched between the first wall body and the second wall body. The gas supply device according to claim 3, wherein the first gas passage is arranged outside so as to sandwich or surround the second gas passage. The light source has a shape in which the direction parallel to the first direction from the first gas inlet to the gas outlet is the longitudinal direction.
The first gas and the second gas both flow in a direction parallel to the first direction and then reach the gas mixing portion, according to any one of claims 1 to 7. Gas supply device. The light source has a shape in which the direction orthogonal to the first direction from the first gas inlet to the gas outlet is the longitudinal direction.
The first gas and the second gas both flow in a direction parallel to the first direction and then reach the gas mixing portion, according to any one of claims 1 to 4. Gas supply device. The first gas passage is characterized in that the passage region located on the gas mixing portion side has a smaller flow path cross-sectional area than the passage region located on the gas inlet side. The gas supply device according to any one of 1 to 9. Any one of claims 1 to 9, wherein the gas mixing portion has a shape in which the cross-sectional area of the flow path is continuously or intermittently reduced toward the gas outlet. The gas supply device described in. The gas supply device according to any one of claims 1 to 11, wherein the ultraviolet light emitted from the light source has a main emission wavelength of less than 230 nm. The gas supply device according to any one of claims 1 to 12, wherein the second gas is an inert gas. It is a surface treatment method for an object.
The step (a) of allowing the first gas containing oxygen, which is a radical source, to flow into the first gas passage, and
The step (b) of irradiating the first gas flowing through the first gas flow path with ultraviolet light from a light source, and
After the step (b), a step (c) of mixing the first gas with a second gas having a lower oxygen concentration than the first gas is added.
A surface treatment method comprising a step (d) of spraying the mixed gas obtained in the step (c) onto the surface of the object.

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