JP2021104498A - Gas supply device - Google Patents

Abstract

To provide a gas supply device which can blow gas containing radical with higher concentration than a conventional gas supply device to an object.SOLUTION: A gas supply device includes: a gas flow passage which allows raw material gas containing a raw material substance used as a radical source to flow; and a light source including which emits ultraviolet light toward the gas flow passage a shape along the gas flow passage. The gas flow passage includes: a gas inflow port to which the raw material gas flows; a gas outflow port which allows treated gas that is the raw material gas after having been irradiated with ultraviolet light to flow out to the outside; and a narrow part (a passing region positioned at the end on the gas outflow port side) which has a smaller flow channel cross-sectional area compared to a position closer to the gas inflow port than the end.SELECTED DRAWING: Figure 1

Description

The present invention relates to a gas supply device, and more particularly to a gas supply device for processing an object by blowing gas after being irradiated with ultraviolet light 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.

The gas supply device according to the present invention
A gas flow path through which a raw material gas containing a raw material that serves as a radical source flows,
It is provided with a light source including a light emitting surface having a shape along the gas passage, which emits ultraviolet light toward the gas passage.
The gas passage is
The gas inlet into which the raw material gas flows and
A gas outlet that allows the treated gas, which is the raw material gas after being irradiated with the ultraviolet light, to flow out to the outside,
It is characterized by including a narrow portion which is a passage region located at an end portion on the gas outlet side and whose flow path cross-sectional area is smaller than that at a position closer to the gas inlet portion than the end portion. ..

In the present specification, "radical" refers to a concept that collectively refers to chemical species (atoms, molecules) having unpaired electrons. As these example, O ⁽³ P), hydroxyl radical (· OH), hydrogen radicals _{(· H), · NH 2} , etc. · NH are exemplified. Of these, when O ( ³ P) is planned as a radical, the raw material is a substance containing an oxygen atom, and examples of the raw gas include a mixed gas containing oxygen and air.

According to the above configuration, the light emitting surface of the light source has a shape along the gas passage through which the raw material gas passes. Therefore, the raw material gas is continuously irradiated with ultraviolet light emitted from the light emitting surface of the light source while flowing through the gas passage toward the gas outlet. As a result, the raw material gas is irradiated with ultraviolet light until it reaches a location near the gas outlet, so that the raw material gas becomes a treated gas containing a high concentration of radicals derived from the raw material.

Further, according to the above configuration, the cross-sectional area of the flow path is smaller at the end of the gas passage on the gas outlet side than at the position closer to the gas inlet than the end (that is, on the upstream side). A narrow part is provided. Therefore, the treated gas containing a high concentration of radicals flows out from the gas outlet in a state where the flow velocity is increased at the time of passing through the narrow portion.

That is, according to the above configuration, the time from the irradiation of the raw material gas with ultraviolet light to the outflow of the raw material gas from the gas outlet as the treated gas is shortened, and the treated gas is discharged from the gas outlet. The time from the start of the outflow to the arrival at the object is also shortened. As a result, a gas containing a higher concentration of radicals (treated gas) can be sprayed onto the object.

Further, on the upstream side of the narrow portion, by making the flow path cross-sectional area larger than that of the narrow portion, the speed of the raw material gas flowing through the main space irradiated with ultraviolet light may be excessively increased. Avoided. As a result, a certain amount of time is secured for the raw material gas to be irradiated with ultraviolet light, so that the treated gas can contain a high concentration of radicals when it reaches the vicinity of the narrow portion.

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-mentioned apparatus for generating a post-treatment gas containing radicals by irradiating the raw material gas with ultraviolet light, ions are not generated, so that charged particles may be sprayed on the object together with the gas. Avoided.

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.

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

According to the above configuration, the effect of further increasing the flow velocity of the treated gas flowing out from the gas outlet is achieved.

At this time, the gas passage may have a shape in which the cross-sectional area of the flow path is continuously or intermittently reduced from the gas inlet to the gas outlet.

Further, with respect to the first direction from the gas inlet to the gas outlet, the narrow portion may be arranged on the gas outlet side of the light emitting surface.

In this case, the light emitting surface and the narrow portion may be continuously arranged in the first direction.

According to the above configuration, since the gas can be irradiated with ultraviolet light until just before the flow velocity of the gas increases, the concentration of radicals contained in the treated gas that has reached the narrow portion is further increased. Then, the treated gas containing radicals in such a high concentration flows out from the gas outlet to the outside in a state where the flow velocity is increased by passing through the narrow portion.

The gas passage may have a first reflecting portion that reflects the ultraviolet light on the inner surface of the region forming the narrow portion.

Depending on the size of the gas passage and the shape of the narrow portion, a part of the ultraviolet light emitted from the light emitting surface may travel toward the inner surface of the region forming the narrow portion. According to the above configuration, the ultraviolet light that has reached the inner surface is reflected, and this reflected light can also be applied to the raw material gas (treated gas), so that the concentration of radicals contained in the treated gas is further improved. The effect of making it is expected.

With respect to the first direction from the gas inlet to the gas outlet, the end of the narrow portion on the gas inlet side is closer to the gas inlet than the end of the light emitting surface on the gas outlet side. It does not matter if they are arranged at close positions.

In this case, the raw material gas (treated gas) passing through the narrow portion can also be irradiated with the ultraviolet light emitted from the light emitting surface. However, if the narrow portion provided for the purpose of increasing the flow velocity of the treated gas is arranged near the gas inflow port, the flow velocity of the raw material gas to be irradiated with ultraviolet light will be accelerated, and the irradiation time will be sufficient. It may not be possible to secure it. From this point of view, the narrow portion is arranged in a region within 30% from the gas outlet side of the length in the gas flow path in the first direction from the gas inlet to the gas outlet. Is preferable, and a region having a length of 20% or less is more preferable, and a region having a length of 10% or less is particularly preferable.

The light source has an arc tube having a hollow tubular space formed inside along the tube axis direction.
The light emitting surface is formed along the side surface of the light emitting tube on the tubular space side.
The gas passage may be formed in the tubular space surrounded by the light emitting surface.

In the above configuration, the second reflecting portion that reflects the ultraviolet light may be provided on the side surface of the arc tube on the side opposite to the tubular space.

According to this configuration, of the ultraviolet light generated in the arc tube, the light traveling on the side opposite to the light emitting surface can be returned to the light emitting surface side, that is, the gas passage side, so that the raw material gas is irradiated. It is possible to increase the amount of ultraviolet light.

The gas supply device has a plurality of the light sources.
A plurality of the light emitting surfaces included in the plurality of light sources may be arranged so as to face each other so as to sandwich the gas passage.

Further, the gas supply device has a tubular housing and has a tubular housing.
The light source is arranged inside the housing and
The gas passage may be formed in a space sandwiched between the light source and the inner surface of the housing.

The light source may have a shape whose longitudinal direction is parallel to the first direction from the gas inlet to the gas outlet.

Further, the gas supply device has a plurality of the light sources, and the gas supply device has a plurality of the light sources.
The plurality of the light sources may have a shape in which the direction orthogonal to the first direction from the gas inlet to the gas outlet is the longitudinal direction, and may be arranged along the first direction.

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 the gas supply device of the present invention, a gas containing radicals (treated 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. Become.

It is sectional drawing which shows typically the structural example of the 1st Embodiment of a gas supply apparatus. It is a schematic cross-sectional view when the gas supply device shown in FIG. 1 is cut from a direction different from that of FIG. It is another schematic sectional view of the gas supply device shown in FIG. 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 typically another configuration example of 1st Embodiment of a gas supply apparatus. 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 another configuration example of 1st Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of the 1st Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of the 1st Embodiment of a gas supply apparatus. It is sectional drawing which shows typically another configuration example of 1st Embodiment of a gas supply apparatus. It is sectional drawing which shows the simulation model structure of Reference Example 1. FIG. 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 schematic cross-sectional view when the structure of the 2nd Embodiment of a gas supply device is cut in the plane orthogonal to the 1st direction. It is a schematic plan view of the light source provided in the 2nd Embodiment of a gas supply device. It is another schematic plan view of the light source provided in 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 the structural example of the 3rd Embodiment of a gas supply apparatus. It is a schematic cross-sectional view when the gas supply device shown in FIG. 15 is cut from a direction different from that of FIG. It is sectional drawing which shows typically another configuration example of the 3rd Embodiment of a gas supply apparatus. It is sectional drawing which shows typically the structural example of the 4th Embodiment of a gas supply apparatus. It is a perspective view which shows typically the structural example of the 4th Embodiment of a gas supply apparatus.

Each embodiment of the gas supply device according to the present invention will be described with reference to the drawings as appropriate. In addition, each of the following drawings is schematically shown, and the dimensional ratio on the drawing and the actual dimensional ratio do not always match. Moreover, the dimensional ratios do not always match between the drawings.

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

"Construction"
FIG. 1 is a cross-sectional view schematically showing a configuration example of the gas supply device of the present embodiment. The gas supply device 1 shown in FIG. 1 includes a tubular housing 3, a light source 5 arranged in the housing 3, and a gas passage 10 through which the raw material gas G1 to be processed passes.

The gas supply device 1 irradiates the raw material gas G1 flowing through the gas flow path 10 with ultraviolet light L1 emitted from the light source 5, and the raw material substance as a radical source contained in the raw material gas G1. To cause a photochemical reaction, a treated gas G2 containing radicals is generated and discharged (supplied) to the outside. That is, the gas supply device 1 is a device for generating and supplying the treated gas G2 containing radicals. Further, in the present specification, the “post-treatment gas G2” refers to the raw material gas G1 after the ultraviolet irradiation treatment is executed.

Here, the raw material gas G1 is a gas containing a raw material that serves as a radical source. As an example, when O ( ³ P) is planned as a radical, the raw material is a substance containing an oxygen atom, and the raw material gas includes, for example, a mixed gas containing oxygen or air. The type of the raw material gas G1 introduced into the gas supply device 1 may be appropriately selected according to the radicals to be generated.

The gas flow path 10 includes a gas inlet 11 into which the raw material gas G1 flows in, and a gas outlet 12 outflowing the treated gas G2 containing radicals generated by irradiation with ultraviolet light L1. Further, in the present embodiment, the gas flow path 10 provided in the gas supply device 1 is located at the end on the gas outlet 12 side, as compared with a position closer to the gas inlet 11 (that is, on the upstream side). It has a flow region (hereinafter referred to as "narrow portion 13") having a small flow path cross-sectional area.

The light source 5 has a light emitting surface 5a that emits ultraviolet light L1 toward the gas flow path 10. The light emitting surface 5a is formed along the shape of the gas flow path 10, that is, along the first direction d1 which is the flow direction of the raw material gas G1 (or the treated gas G2). That is, this first direction d1 is a direction from the gas inflow port 11 toward the gas outflow port 12.

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. 1 when it is cut in a plane orthogonal to the first direction d1. On the other hand, FIG. 1 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 gas passage passage 10.

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 is irradiated toward the hollow tubular space formed inside the arc tube 21 through this gap, that is, the gas flow path 10. ..

That is, the light source 5 has a light emitting surface 5a (see FIG. 1) 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 may have a mesh shape or a line shape, and a reflecting member 33 that reflects ultraviolet light L1 may be provided between the first electrode 31 and the housing 3. 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, and the like can be used. The reflective member 33 corresponds to the "second reflective portion".

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

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 a gas containing oxygen (O 2} ) is adopted as the raw material gas G1, when the ultraviolet light L1 of the wavelength λ emitted from the light source 5 is irradiated _{and absorbed by the oxygen (O 2} ), the following (1) The reactions of Eq. And Eq. (2) proceed. In equation (1), 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 (1) and (2) occurs depending on the wavelength component of the ultraviolet light L1.
O ₂ + hν (λ) → O ( ¹ D) + O ( ³ P) ‥‥ (1)
O ₂ + hν (λ) → O ( ³ P) + O ( ³ P) ‥‥ (2)

That is, when the raw material gas G1 is irradiated with ultraviolet light L1, the treated gas G2 containing radicals such as ^{O (1} D) and O ( ^{3 P) is generated.} Since the light emitting surface 5a of the light source 5 extends along the first direction d1, the ultraviolet light L1 is continuously irradiated even while the treated gas G2 is flowing through the gas flow path 10. Therefore, a photochemical reaction occurs one after another with respect to the raw material which is an unreacted radical source contained in the treated gas G2. As a result, the treated gas G2 proceeds to the region where the narrow portion 13 is formed while containing a high concentration of radicals.

In the above description, the case where the radical to be contained in the treated gas G2 is ^{an oxygen radical such as O (3} P) and the raw material is oxygen (O ₂ ) is described. When it is desired to generate the treated gas G2 containing radicals, the material of the raw material gas G1 and the wavelength of the ultraviolet light L1 are selected according to the radical source to be contained.

As described above, the narrow portion 13 has a shape in which the cross-sectional area of the flow path is smaller than the position on the upstream side of the narrow portion 13 in the gas flow path 10. In the gas supply device 1 shown in FIG. 1, the narrow portion 13 has a shape in which the cross-sectional area of the flow path continuously decreases as it approaches the gas outlet 12.

The treated gas G2 that has reached the narrow portion 13 travels toward the gas outlet 12 while increasing the flow velocity when flowing through the narrow portion 13, and then is discharged from the gas outlet 12.

That is, according to the above configuration, since the flow path cross-sectional area in the gas passage 10 is large on the upstream side of the narrow portion 13, that is, on the gas inflow port 11 side, it is later than the time when it passes through the narrow portion 13. The raw material gas G1 flows through the gas flow path 10 at a flow velocity. Therefore, the time for irradiating the raw material gas G1 with the ultraviolet light L1 from the light source 5 for a long time is secured, and a sufficient amount of irradiation light for generating radicals by the photochemical reaction is secured.

Further, since the light emitting surface 5a of the light source 5 extends along the first direction d1, the light source gas G1 (or the treated gas G2) reaches a portion near the narrow portion 13 from the light source 5. Ultraviolet light L1 is irradiated. Therefore, the treated gas G2 that has reached a portion near the narrow portion 13 is in a state of containing radicals at a high concentration. After that, the treated gas G2 is discharged to the outside through the gas outlet 12 while increasing the flow velocity when flowing through the narrow portion 13. As a result, the gas supply device 1 can discharge the treated gas G2 in a state of containing radicals in a high concentration.

The gas supply device 1 shown in FIG. 1 has a position related to the first direction d1 of the end portion of the light emitting surface 5a of the light source 5 on the gas outlet 12 side and an end portion of the narrow portion 13 on the gas inlet 11 side. The positions related to the first direction d1 are almost the same. That is, the light emitting surface 5a and the narrow portion 13 are continuously arranged with respect to the first direction d1. According to this configuration, since the gas is irradiated with ultraviolet light L1 until just before the flow velocity of the gas increases, the concentration of radicals contained in the treated gas G2 that has reached the narrow portion 13 is further increased.

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

<1> As shown in FIG. 5, a reflecting surface 13a showing reflectivity to ultraviolet light L1 may be provided at a position related to the inner surface of the narrow portion 13. The reflecting surface 13a corresponds to the "first reflecting portion".

Similar to the gas supply device 1 shown in FIG. 1, the gas supply device 1 shown in FIG. 5 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 gas passage 10 side with a predetermined divergence angle, a part of the ultraviolet light L1 is emitted from the light emitting surface 5a at a position close to the narrow portion 13. Is expected to progress toward the narrow portion 13. In such a case, by forming the reflecting surface 13a on the inner surface of the narrow portion 13 as shown in FIG. 5, the ultraviolet light L1 reflected by the reflecting surface 13a can be returned to the upstream side of the narrow portion 13. .. As a result, the amount of ultraviolet light L1 irradiated to the raw material gas G1 (and the treated gas G2) is increased, so that the effect of further increasing the concentration of radicals contained in the treated gas G2 can be obtained.

The reflecting surface 13a 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 13, 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 13 is formed is used. It does not matter if the reflective surface 13 is realized.

<2> As shown in FIG. 6, the light emitting surface 5a may extend to the region forming the narrow portion 13. In the gas supply device 1 shown in FIG. 6, by widening the shape of the light source 5 at a position close to the gas outlet 12, the cross-sectional area of the gas passage 10 is small at a position close to the gas outlet 12. The narrow portion 13 is formed.

In the case of such a configuration, since the flow velocity of the gas (raw material gas G1, treated gas G2) flowing through the narrow portion 13 is increased, the irradiation of ultraviolet light L1 is compared with that on the upstream side of the narrow portion 13. The amount of light is low. However, at a position upstream of the narrow portion 13, the raw material gas G1 has already been irradiated with the ultraviolet light L1 of the irradiation light amount required to generate radicals, and therefore, when the narrow portion 13 is reached, the radicals are reached. It is changed to the treated gas G2 containing a large amount of. Compared with the structure shown in FIG. 1, the structure shown in FIG. 6 further adds radicals to the gas flowing through the narrow portion 13 by irradiating the gas passing through the narrow portion 13 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. 7, a translucent member 9 exhibiting transparency to the ultraviolet light L1 is arranged on the light emitting surface 5a at a position close to the gas outlet 12. The narrow portion 13 may be formed by the region surrounded by the translucent member 9. In this case, the translucent member 9 has a hollow tubular shape penetrating with respect to the first direction d1, and the opening area of the tubular body is smaller on the gas outlet 12 side than on the gas inlet 11 side. Also in this case, the treated gas G2 passing through the narrow portion 13 formed by the inside of the translucent member 9 is discharged to the outside through the gas outlet 12 while increasing the flow velocity at the time of passage. Further, when passing through the narrow portion 13, the ultraviolet light L1 emitted from the light emitting surface 5a passes through the translucent member 9 and is irradiated to the gas (raw material gas G1, processed gas G2). Therefore, as in the case of the structure shown in FIG. 6, an effect that additional radicals can be generated can be obtained as compared with the structure shown in FIG.

Such a translucent member 9 is made of, for example, a material such as quartz or magnesium fluoride. In such a case, the light transmitting member 9 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. 1, the narrow portion 13 has a shape in which the cross-sectional area of the flow path continuously decreases as it approaches the gas outlet 12. However, the narrow portion 13 has a shape as long as the narrow portion 13 has a shape in which the cross-sectional area of the flow path is smaller than the position on the upstream side (gas inflow port 11 side) of the narrow portion 13 in the gas flow path 10. Is optional. This point is the same in the gas supply device 1 shown in FIGS. 5 to 7.

For example, as shown in FIG. 8A, 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 13. Further, as shown in FIG. 8B, 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 13. 8A and 8B are enlarged cross-sectional views of the vicinity of the gas outlet 12 in the gas supply device 1.

<4> As described above with reference to FIG. 2 or FIG. 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.

For example, as shown in FIG. 9, the gas supply device 1 may include a light source 5 having a rectangular annular arc tube 21. In this case, the gas passage 10 formed by the inside of the inner pipe 21b also has a rectangular shape when viewed from the first direction d1.

"inspection"
According to the gas supply device 1, the point that the treated gas G2 discharged from the gas outlet 12 contains a high concentration of radicals was verified by using a simulation.

10A and 10B are cross-sectional views schematically showing a model of the gas supply device used in this simulation. The gas supply device 100 shown in FIG. 10A corresponds to Reference Example 1, and the gas supply device 1 shown in FIG. 10B corresponds to Example 1.

(Reference example 1)
The gas supply device 100 of Reference Example 1 is provided in a light source 5 having a light emitting surface 5a having a side surface 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. It was provided with a gas flow path 10. The gas passage 10 includes a circular gas inlet 11 having a diameter of 5 mm and a circular gas outlet 12 having a diameter of 5 mm.

(Example 1)
Similar to the gas supply device 100 of Reference Example 1, the gas supply device 1 of the first embodiment is a light source 5 having a light emitting surface 5a having a side surface shape of a tubular body having a length h1 of 50 mm in the first direction d1. And the gas flow path 10 was provided in the region surrounded by the light emitting surface 5a. However, the gas passage 10 includes a region where the inner diameter of the tubular body is uniform, and a narrow portion 13 whose inner diameter decreases as it approaches the gas outlet 12.

The gas passage 10 includes a circular gas inlet 11 having a diameter of 5 mm and a circular gas outlet 12 having a diameter of 2.5 mm. Further, in the gas flow path 10, the length h2 related to the first direction d1 of the region closer to the gas inflow port 11 than the narrow portion 13 is 40 mm, and the length h2 is in the first direction d1 of the region constituting the narrow portion 13. The length h3 was 10 mm. That is, in the gas supply device 1 of the first embodiment, the length h1 of the entire gas passage 10 in the first direction d1 was 50 mm, which is the same as that of the reference example 1.

The light source 5 included in the gas supply device 1 corresponding to the first embodiment and the gas supply device 100 corresponding to the reference example 1 was an Xe excimer lamp having a main peak wavelength of 172 nm.

(result)
With respect to the models of Reference Example 1 and Example 1, a predetermined flow rate from the gas inlet 11 while irradiating the gas flow path 10 with ultraviolet light L1 ^{from the light source 5 at an illuminance of 50 mW / cm 2 on the light emitting surface 5a.} The raw material gas G1 of the above was introduced. Then, in each model, it is assumed that the object 40 to which the treated gas G2 is sprayed is installed at a position where the separation distance v1 from the gas outlet 12 in the first direction d1 is 10 mm (FIGS. 10A and 10B). (See), the concentration of radicals on the surface of this object 40 was measured.

More specifically, the calculation was performed under the following simulation conditions.
The object 40 had a circular shape with a radius r1 of 20 mm, the center of which was arranged on the central axis of the gas flow path 10.
The raw material gas G1 was a mixed gas of 99.5% nitrogen gas and 0.5% oxygen gas, and was introduced into the gas supply device (100, 1) from the gas inlet 11 at a flow rate of 30 L / min. ..
-For both the gas supply device 100 of Reference Example 1 and the gas supply device 1 of Example 1, a radius of 2.5 mm from the center of the surface of the object 40 arranged to face the gas outlet 12 of each device. The average concentration of ^{oxygen radical O (3} P) contained in the treated gas G2 injected into the region within the range of (φ5 mm) was calculated.

The calculation result is shown in FIG. According to FIG. 11, in Example 1, the average concentration of ^{oxygen radicals O (3} P) contained in the treated gas G2 sprayed on the surface of the object 40 is significantly higher than that in Reference Example 1. Was confirmed.

The model of Example 1 shown in FIG. 10B has a narrow portion 13 in order to share the length h1 of the gas flow path 10 in the first direction d1 with the model of Reference Example 1 shown in FIG. 10A. The light emitting surface 5a formed in the constituent region shows a bent shape. Therefore, in the model of Example 1 shown in FIG. 10B, the area of the entire light emitting surface 5a is slightly reduced as compared with the model of Reference Example 1 shown in FIG. 10A (Example 1: 785 mm ² , Reference Example). 1: 747 mm ² ). However, as shown in FIG. 11, the average concentration of ^{oxygen radical O (3 P) in Example 1 is significantly higher than that in Reference Example 1.}

From the above simulation results, the gas supply device 1 of the first embodiment provides the narrow portion 13 on the gas outlet 12 side of the gas flow path 10, so that the treated gas G2 flowing out from the gas outlet 12 ^{As a result of increasing the flow velocity, it is considered that the ratio of oxygen radicals (O (3} P)) contained in the treated gas G2 reaching the surface of the object 40 before being inactivated is increased.

When oxygen gas (O ₂ ) is present, the oxygen radical (O ( ³ P)) reacts with the oxygen gas (O 2) to generate _{ozone (O 3} ) according to the equation (3). If such a reaction occurs, the concentration of O ⁽³ P) decreases.
O ( ³ P) + O ₂ → O ₃ ‥‥ (3)

In the case of the gas supply device 100 of Reference Example 1, the reaction of the above (3) is likely to occur before the treated gas G2 flowing out from the gas outlet 12 reaches the surface of the object 40. a result, the concentration of O ⁽³ P) contained in the processed blown to the surface of the object 40 the gas G2 is assumed that was lower than in example 1.

From the above simulation results, even in the case of the structure shown in each of FIGS. 1 and 5 to 8B described above, the gas supply device 1 also contains a high concentration of radicals in the treated gas G2. It can be seen that the object 40 is sprayed in the state of being.

[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. 12 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 of FIG.

In the first embodiment, it is assumed that the gas passage 10 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 gas passage 10 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 gas flow path 10.

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 gas passage 10 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. 13A 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. 13A 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. 13B is a cross-sectional view schematically illustrated according to FIG. 13A 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 gas flow path 10 side have a mesh shape (mesh shape) so as not to prevent the ultraviolet light L1 from being emitted to the outside of the arc tube 21. ) Or has a linear shape.

Also in the light source 5 shown in FIGS. 13A and 13B, 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> As shown in FIG. 14, the gas supply device 1 includes a plurality of light sources 5 arranged so as to face each other with a gas flow path 10 interposed therebetween, and a light emitting surface 5a included in each light source 5 is provided. By arranging the gas flow path 10 with an inclination with respect to the first direction d1, the flow path cross-sectional area of the gas flow path 10 may be configured to be reduced as it approaches the gas outlet 12. ..

<3> 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. ..

[Third Embodiment]
The third 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. 15 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. 16 is a schematic cross-sectional view of the gas supply device 1 shown in FIG. 15 when the gas supply device 1 is cut in a plane orthogonal to the first direction d1.

In the first embodiment and the second embodiment, the gas passage 10 is formed in the region surrounded by the light emitting surface 5a. On the other hand, the present embodiment is different in that the gas passage 10 is formed between the light emitting surface 5a and the inner side surface 3a of the housing 3.

That is, as shown in FIG. 15, the light source 5 arranged in the housing 3 is arranged so that the light emitting surface 5a is surrounded by the inner side surface 3a of the housing 3. That is, the raw material gas G1 passes through the gas flow path 10 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 second 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> As in the gas supply device 1 shown in FIG. 17, another light source 5 may be arranged on the inner side surface 3a side of the housing 3 with respect to the gas supply device 1 shown in FIG. In this case, the gas passage 10 is formed by the regions sandwiched between the light emitting surfaces 5a of the facing light sources 5.

[Fourth Embodiment]
The third 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. 18 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. 19 is a schematic cross-sectional view of the gas supply device 1 shown in FIG.

In each of the above embodiments, the light source 5 has been described as having a light emitting surface 5a extending along the first direction d1. On the other hand, the gas supply device 1 of the present embodiment has a plurality of light sources 5 arranged along the first direction d1, and each light source 5 has a second direction orthogonal to the first direction d1. It has a light emitting surface 5a extending along d2. That is, each light source 5 has a shape in which the second direction is the longitudinal direction.

More specifically, the gas supply device 1 shown in FIGS. 18 and 19 faces the light sources 5 (51, 52, 53) arranged along the first direction d1 and the light emitting surface 5a of these light sources 5. It is equipped with a light source 5 (54, 55, 56) arranged so as to. The light emitting surface 5a of each light source 5 extends in the second direction d2.

Since the other points are common to the first embodiment, the description is omitted from the viewpoint of avoiding duplication. Even in such a case, the light emitting surfaces 5a composed of the plurality of light sources 5 are arranged along the first direction d1 which is the direction in which the raw material gas G1 flows, and the gas flow path 10 is the gas outlet. A narrow portion 13 having a small flow path cross-sectional area is formed in the vicinity of 12. Therefore, as in the first embodiment, the treated gas G2 can be discharged from the gas outlet 12 in a state containing a high concentration of radicals.

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

Even when the gas passage 10 is formed between the light emitting surface 5a and the inner side surface 3a of the housing 3, as in the gas supply device 1 of the third embodiment shown in FIG. Similar to the embodiment, it is possible to adopt a configuration in which a plurality of light sources 5 having a light emitting surface 5a extending in the second direction d2 are arranged along the first direction d1.

In this embodiment, the number of light sources 5 is arbitrary. Further, as the light source 5, various excimer lamps having a double tube structure, a single tube structure, a flat tube structure, and a plurality of ultraviolet LED elements arranged in the plane direction can be adopted.

1: Gas supply device 3: Housing 3a: Inner surface of the housing 5: Light source 5a: Light emitting surface 9: Transmissive member 10: Gas passage 11: Gas inlet 12: Gas outlet 13: Narrow portion 13a: Reflective surface 21: Light emitting tube 21a: Outer tube 21b: Inner tube 23G: Luminous gas 31: First electrode 32: Second electrode 33: Reflecting member 40: Object 51, 52, 53, 54, 55, 56: Light source 100 : Reference example gas supply device G1: Raw material gas G2: Treated gas L1: Ultraviolet light d1: First direction d2: Second direction

Claims (15)

A gas flow path through which a raw material gas containing a raw material that serves as a radical source flows,
It is provided with a light source including a light emitting surface having a shape along the gas passage, which emits ultraviolet light toward the gas passage.
The gas passage is
The gas inlet into which the raw material gas flows and
A gas outlet that allows the treated gas, which is the raw material gas after being irradiated with the ultraviolet light, to flow out to the outside,
It is characterized by including a narrow portion which is a passage region located at an end portion on the gas outlet side and whose flow path cross-sectional area is smaller than that at a position closer to the gas inlet portion than the end portion. , Gas supply device. The gas supply device according to claim 1, wherein the narrow portion has a shape in which the cross-sectional area of the flow path is continuously or intermittently reduced as it approaches the gas outlet. The second aspect of the present invention is characterized in that the gas passage has a shape in which the cross-sectional area of the flow passage is continuously or intermittently reduced from the gas inlet to the gas outlet. The gas supply device described. The first or second aspect of the present invention, wherein the narrow portion is arranged on the gas outlet side of the light emitting surface with respect to the first direction from the gas inlet to the gas outlet. Gas supply device. The gas supply device according to claim 4, wherein the light emitting surface and the narrow portion are continuously arranged in the first direction. The gas supply device according to claim 4 or 5, wherein the gas passage has a first reflection portion that reflects the ultraviolet light on the inner surface of the region forming the narrow portion. With respect to the first direction from the gas inlet to the gas outlet, the end of the narrow portion on the gas inlet side is closer to the gas inlet than the end of the light emitting surface on the gas outlet side. The gas supply device according to claim 1 or 2, wherein the gas supply device is arranged at a close position. The light source has an arc tube having a hollow tubular space formed inside along the tube axis direction.
The light emitting surface is formed along the side surface of the light emitting tube on the tubular space side.
The gas supply device according to any one of claims 1 to 7, wherein the gas passage is formed in the tubular space surrounded by the light emitting surface. The gas supply device according to claim 8, further comprising a second reflecting portion that reflects the ultraviolet light on a side surface of the arc tube opposite to the tubular space. It has multiple light sources and
The gas supply according to any one of claims 1 to 7, wherein a plurality of light emitting surfaces included in the plurality of light sources are arranged so as to face each other so as to sandwich the gas passage. Device. It has a tubular housing and
The light source is arranged inside the housing and
The gas supply device according to any one of claims 1 to 7, wherein the gas passage is formed in a space sandwiched between the light source and the inner side surface of the housing. The gas supply device according to claim 10 or 11, wherein the light source has a shape whose longitudinal direction is parallel to the first direction from the gas inlet to the gas outlet. It has multiple light sources and
The plurality of light sources have a shape whose longitudinal direction is orthogonal to the first direction from the gas inlet to the gas outlet, and are arranged along the first direction. The gas supply device according to claim 10 or 11. The gas supply device according to any one of claims 1 to 13, 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 14, wherein the raw material is a substance containing an oxygen atom.

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