Gas Supply Equipment

Abstract

To provide a gas supplying device capable of blowing a gas containing radicals at a higher concentration than before to an object.SOLUTION: There is provided a gas supplying device which comprises: a gas inflow port into which a raw material gas containing a raw material as a radical source flows; a gas flow path in which the raw material gas flowed from the gas inflow port flows; a light source emitting ultraviolet light to the light irradiation area in the gas flow path; a gas outflow port for allowing treated gas which is a raw material gas having been irradiated with ultraviolet light to flow to the outside; and a first heating part for raising the temperature of the raw material gas at a position on the gas inflow port side from the light irradiation area.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gas supply device, and more particularly to a gas supply device for processing an object by spraying a gas that has been irradiated with ultraviolet light onto the object. [Background technology]

[0002] Conventionally, a technique has been known for removing organic compounds adhering to the surface of an object, in which a gas is activated by irradiating the gas with vacuum ultraviolet light, and the activated gas is then sprayed onto the surface of the object (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-98357 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, according to intensive research by the present inventors, it has been found that a gas containing a high concentration of radicals cannot be sprayed onto an object with the structure described in Patent Document 1. The present inventors speculate that the reason for this is that, with the structure described in Patent Document 1, the light source for irradiating the gas with ultraviolet light to generate radicals is too far away from the location of the object onto which the gas containing radicals is sprayed, so that many of the radicals are deactivated before the gas reaches the object.

[0005] In view of the above problems, an object of the present invention is to provide a gas supplying device capable of spraying a gas containing radicals at a higher concentration than ever before onto a target object. [Means for solving the problem]

[0006] The gas supply device according to the present invention comprises: a gas inlet into which a source gas containing a source material serving as a radical source is introduced; a gas flow passage through which the raw material gas flows after being introduced from the gas inlet; a light source that emits ultraviolet light toward a light irradiation region in the gas flow passage; a gas outlet through which a treated gas, which is the raw material gas after being irradiated with the ultraviolet light, is discharged to the outside; The gas supply system further comprises a first heating section for increasing the temperature of the source gas at a position closer to the gas inlet than the light irradiation region.

[0007] In this specification, the term "radical" refers to a general term for chemical species (atoms, molecules) that have an unpaired electron. 3 P), hydroxyl radical (·OH), hydrogen radical (·H), NH 2 , NH, etc. Among these, the radical O( 3 When P) is planned, the source material is a material containing oxygen atoms, and the source gas can be, for example, a mixed gas containing oxygen or air.

[0008] Radicals are highly reactive and have an extremely short lifespan. More specifically, radicals disappear within a short period of time by bonding with other atoms or molecules in the gas surrounding the radicals. For this reason, the configuration of Patent Document 1 makes it difficult to irradiate a target object with a gas containing a high concentration of radicals.

[0009] For example, when the raw material serving as the radical source is a material containing oxygen atoms, oxygen radicals O( 3 P) easily combines with oxygen molecules to form ozone (O 3 ) O( 3 P) + O 2 → O 3 ...(1)

[0010] The gas supply device according to the present invention includes a first heating unit that heats up the temperature of the raw material gas at a position upstream of the light irradiation region in the gas flow direction. That is, the raw material gas in a heated state is supplied to the light irradiation region and irradiated with ultraviolet light. Once generated, the radicals are less likely to undergo a bonding reaction with other atoms or molecules the higher the temperature.

[0011] In addition, ozone (O 3 ) has a property of absorbing ultraviolet light slightly more easily than oxygen (O2). 3 By suppressing the amount of radicals produced, ultraviolet light can easily reach the gas flow passage, thereby increasing the efficiency of radical production.

[0012] That is, according to the above-mentioned configuration, the raw material gas is irradiated with ultraviolet light while the temperature thereof is elevated, so that radicals once generated are less likely to be deactivated. This makes it possible to discharge the processed gas containing radicals at a higher concentration than in the past to the outside.

[0013] Furthermore, some raw materials that are radical sources release radicals again when the products generated by the radicals bonding with atoms or molecules are decomposed. For example, when the raw material contains oxygen atoms, ozone (O 3 ) to obtain the oxygen radical O( 3 P) may be generated again. O 3 → O( 3 P) + O 2 ...(2)

[0014] The reaction in formula (2) above is the reverse reaction of formula (1) above, and produces ozone (O 3 This is likely to occur when the temperature of the gas containing the radicals is high. Therefore, according to the above configuration, depending on the source material serving as the radical source, the probability that radicals that have once bonded and disappeared will be generated again increases, and the radical concentration can be further increased.

[0015] The gas flow passage may be covered with a heat retaining member at least at a position between the first heating section and the light irradiation region.

[0016] According to the above-mentioned configuration, the source gas can be led to the light irradiation region while being maintained at a high temperature, thereby further improving the radical concentration contained in the processed gas.

[0017] The gas supply device may include a plurality of gas inlets through which a plurality of source gases having different gas temperatures are introduced.

[0018] The gas supply device may include a second heating section that heats the raw material gas or the processed gas flowing through the light irradiation region.

[0019] According to the above-mentioned configuration, the raw material gas or the processed gas flows through the light irradiation region while maintaining a high temperature, and is guided to the gas outlet side, thereby further increasing the concentration of radicals contained in the processed gas.

[0020] The ultraviolet light emitted from the light source may have a light intensity in a wavelength range of less than 230 nm. More preferably, the ultraviolet light emitted from the light source may have a main emission wavelength of less than 230 nm.

[0021] In this specification, the term "main emission wavelength" refers to the emission wavelength with the highest light intensity, or the wavelength λi in the wavelength range Z(λi) showing an integrated intensity of 40% or more of the total integrated intensity in the emission spectrum when a wavelength range Z(λ) of ±10 nm from a certain wavelength λ is defined on the emission spectrum. For example, in a light source that has an extremely narrow half-width and shows light intensity only at a specific wavelength, such as an excimer lamp filled with a specific luminous gas, the wavelength with the highest relative intensity (main peak wavelength) may usually be taken as the main emission wavelength.

[0022] The light source may be, for example, an excimer lamp that uses, as a light emitting gas, a gas containing at least one material belonging to the group consisting of Xe, Ar, Kr, ArBr, ArF, KrCl, and KrBr. For example, an excimer lamp that contains Xe as a light emitting gas has a main emission wavelength of ultraviolet light of 172 nm.

[0023] According to this configuration, by placing the object to be treated at a position 10 mm away from the gas outlet, the post-treatment gas containing a high concentration of radicals can be sprayed onto the object to be treated. Effect of the Invention

[0024] According to the gas supply device of the present invention, a gas (treated gas) containing radicals at a higher concentration than in the past can be caused to flow out from the gas outlet, and such gas can be sprayed against a target object. [Brief description of the drawings]

[0025] [Figure 1] FIG. 2 is a cross-sectional view illustrating a configuration example of a gas supply device. [Diagram 2] 2 is a schematic cross-sectional view of the gas supply device shown in FIG. 1, taken in a direction different from that in FIG. 1. [Diagram 3] 2 is another schematic cross-sectional view of the gas supply device shown in FIG. 1, taken in a direction different from that in FIG. [Figure 4] 1 is a graph showing an emission spectrum of an excimer lamp filled with a light-emitting gas containing Xe and an absorption spectrum of oxygen (O2) superimposed on each other. [Diagram 5] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 6] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 7] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 8] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 9]FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 10] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 11] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 12] 12 is a cross-sectional view showing a schematic configuration example of a light source provided in the gas supply device shown in FIG. [Figure 13] 12 is a cross-sectional view showing a schematic configuration example of a light source provided in the gas supply device shown in FIG. [Figure 14] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 15] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 16] FIG. 11 is a cross-sectional view illustrating another configuration example of a gas supply device. [Figure 17] FIG. 2 is a cross-sectional view showing a model structure of a gas supply device used in a simulation. [Figure 18] 13 is a graph showing a simulation result. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] An embodiment of a gas supply device according to the present invention will be described below. Note that the following drawings are merely schematic illustrations, and the dimensional ratios in the drawings do not necessarily match the actual dimensional ratios. Furthermore, the dimensional ratios may not match between the drawings.

[0027] "structure" Fig. 1 is a cross-sectional view showing a schematic configuration example of a gas supply device of this embodiment. The gas supply device 1 shown in Fig. 1 includes a cylindrical housing 3, a light source 5 arranged in the housing 3, a gas inlet 11 into which a raw material gas G1 to be processed flows, a gas flow passage 10 through which the raw material gas G1 flows, and a heating unit 51 (corresponding to a "first heating unit"). The gas supply device 1 also includes a gas outlet 12 connected to the gas flow passage 10 and at an end opposite to the gas inlet 11 (an end on the side of a target object 40 to be described later). The heating unit 51 will be described later.

[0028] The gas supply device 1 irradiates the raw material gas G1 flowing through the gas flow passage 10 with ultraviolet light L1 emitted from the light source 5, causing a photochemical reaction in the raw material material that serves as a radical source contained in the raw material gas G1, and generates a processed gas G2 containing radicals, which is discharged (supplied) to the outside. In other words, the gas supply device 1 is an apparatus for generating and supplying the processed gas G2 containing radicals. In addition, in this specification, the "processed gas G2" refers to the raw material gas G1 after the ultraviolet irradiation process has been performed.

[0029] More specifically, a light irradiation region 5b is formed in the gas flow passage 10, where the ultraviolet light L1 emitted from the light source 5 is irradiated. When the raw material gas G1 passes through the light irradiation region 5b, a processed gas G2 containing radicals is generated from the raw material gas G1.

[0030] 1 also shows an object 40 placed at a position facing the gas outlet 12. The surface of the object 40 (object surface) is sprayed with a post-treatment gas G2 containing radicals, thereby subjecting the object 40 to surface treatment.

[0031] The source gas G1 is a gas containing a source material that serves as a radical source. As an example, O( 3 In the case where the radical generation is planned, the source material is a material containing oxygen atoms, and the source gas may be, for example, a mixed gas containing oxygen or air. The type of the source gas G1 introduced into the gas supply device 1 may be appropriately selected depending on the radical to be generated.

[0032] The light source 5 has a light emitting surface 5a that emits ultraviolet light L1 toward the gas flow passage 10. The light emitting surface 5a is formed along the shape of the gas flow passage 10, in other words, along the flow direction of the raw material gas G1 (or the processed gas G2).

[0033] In the gas supply device 1 shown in FIG. 1, the light source 5 has a shape extending in a direction d1 from the gas inlet 11 toward the gas outlet 12 as a longitudinal direction. In this embodiment, an excimer lamp is used as an example of the light source 5. An example of the structure in this case will be described with reference to FIG. 2. FIG. 2 is a schematic cross-sectional view of the gas supply device 1 shown in FIG. 1, where the light source 5 is arranged, cut along a plane formed by the directions d2 and d3. FIG. 1 is a schematic cross-sectional view of the gas supply device 1 cut along a plane formed by the directions d1 and d3.

[0034] 2, the light source 5 disposed inside the housing 3 has an arc tube 21 extending along the direction d1. More specifically, the arc tube 21 has an outer tube 21a having a cylindrical shape and located on the outside, and an inner tube 21b having a cylindrical shape and a smaller inner diameter than the outer tube 21a, which is disposed coaxially inside the outer tube 21a. Both arc tubes 21 (21a, 21b) are made of a dielectric material such as synthetic quartz glass.

[0035] A hollow cylindrical space is formed penetrating the inner pipe 21b along the pipe axial direction, and this cylindrical space constitutes the gas flow passage 10.

[0036] Both the outer tube 21a and the inner tube 21b are sealed at their ends in the direction d1 (not shown), and a light-emitting space having a circular shape when viewed from the direction d1 is formed between the outer tube 21a and the inner tube 21b. A light-emitting gas 23G that forms excimer molecules by discharge is enclosed in this light-emitting space.

[0037] The wavelength of the ultraviolet light L1 emitted from the light emitting tube 21 is determined by the material of the light emitting gas 23G. In other words, the material of the light emitting gas 23G is appropriately selected according to the wavelength desired to be obtained as the ultraviolet light L1. The light emitting gas 23G may 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 light emitting gas 23G is realized by these materials, the main emission wavelength of the ultraviolet light L1 is less than 230 nm.

[0038] The light source 5 illustrated in Fig. 2 has a first electrode 31 disposed on the outer wall surface of the outer tube 21a and a second electrode 32 disposed 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 line shape like the second electrode 32. These electrodes (31, 32) are connected to a power supply line (not shown).

[0039] 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 of the light source 5 constituted by an excimer lamp via a power supply (not shown), the voltage is applied to the light emitting gas 23G via the arc tube 21. At this time, a discharge plasma is generated in the discharge space in which the light emitting gas 23G is sealed, and the atoms of the light emitting gas 23G are excited to an excimer state, and excimer emission occurs when the atoms transition to the ground state. When the gas containing xenon (Xe) described above is used as the light emitting gas 23G, the excimer emission becomes ultraviolet light L1 having a peak wavelength in the vicinity of 172 nm.

[0040] As described above, the second electrode 32 having a mesh shape or a line shape is formed on the inner tube 21b of the arc tube 21. Therefore, a gap exists in the second electrode 32, and the ultraviolet light L1 is irradiated through this gap toward a hollow cylindrical space formed inside the arc tube 21, i.e., toward the light irradiation region 5b in the gas flow passage 10.

[0041] 3, the first electrode 31 may be formed in a mesh or line shape, and a reflective member 33 that reflects the 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 high reflectance (e.g., 80% or more) to the ultraviolet light L1, and may be, for example, Al, Al alloy, stainless steel, silica, silica alumina, etc. When the housing 3 itself is made of a material that exhibits reflectivity to the ultraviolet light L1 (e.g., stainless steel such as SUS), the surface of the housing 3 may be used as the reflective member 33.

[0042] In addition, in Figures 2 and 3, the shape of the light-emitting tube 21 when cut in a plane formed by directions d2 and d3 is shown to be circular, but it may also be rectangular or have some other shape.

[0043] FIG. 4 shows the emission spectrum of the light source 5, which is an excimer lamp filled with a light-emitting gas 23G containing Xe, and the emission spectrum of oxygen (O 2 4, the horizontal axis indicates the wavelength, the left vertical axis indicates the relative value of the light intensity of the excimer lamp, and the right vertical axis indicates the absorption spectrum of oxygen (O 2 ) is the absorption coefficient.

[0044] When a gas containing Xe is used as the light emitting 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 a band within the range of approximately 160 nm to 190 nm.

[0045] The source gas G1 is oxygen (O 2 When a gas containing oxygen (O 2 When O( 1 D) is an excited state of O atom and is extremely reactive. O( 3 P) is an O atom in the ground state. The reactions of (3) and (4) occur depending on the wavelength component of the ultraviolet light L1. O 2 + hν(λ) → O( 1 D) + O( 3 P) ...(3) O 2 + hν(λ) → O( 3 P) + O( 3 P) ...(4)

[0046] That is, when the source gas G1 is irradiated with ultraviolet light L1, O( 1 D) and O( 3 A processed gas G2 containing radicals such as radicals (radicals R, R, and P) is generated. Since the light emitting surface 5a of the light source 5 extends along the direction d1, the ultraviolet light L1 continues to be irradiated even while the processed gas G2 is flowing through the gas flow passage 10. Therefore, photochemical reactions occur one after another in the raw materials that are unreacted radical sources contained in the processed gas G2. As a result, the processed gas G2 is flowed toward the gas outlet 12 while still containing a high concentration of radicals.

[0047] In the above, the radicals to be contained in the post-processing gas G2 are O( 3 P, etc., and the raw material is oxygen (O 2 ), but if you want to generate a processed gas G2 containing other radicals, the material of the source gas G1 and the wavelength of the ultraviolet light L1 are selected depending on the radical source you want to include.

[0048] 1 includes a heating unit 51 on the gas inlet 11 side of the light irradiation area 5b, i.e., upstream of the light irradiation area 5b. The heating unit 51 may be a known heating means, such as a halogen lamp, a ceramic heater, or an electric heating wire.

[0049] The heating unit 51 heats the raw material gas G1 flowing in from the gas inlet 11. As a result, the raw material gas G1 is guided to the light irradiation region 5b in a heated state. That is, the raw material gas G1 is irradiated with ultraviolet light L1 at a high temperature. As an example, the raw material gas G1 is heated to a temperature of about 100°C or more and 300°C or less.

[0050] Radicals are highly reactive and have an extremely short lifespan. More specifically, radicals bond with other atoms or molecules in the gas surrounding the radicals, causing the radicals to disappear within a short period of time. For example, the O( 3 P) is easily eliminated according to formula (1) mentioned above in the section "Means for solving the Problems." Formula (1) is shown below again. O( 3 P) + O 2 → O 3 ...(1)

[0051] However, the higher the temperature, the slower the rate of the radical bonding reaction defined by the above formula (1) etc. Therefore, according to the gas supply device 1 of the present embodiment, the rate at which radicals generated while the source gas G1 passes through the light irradiation region 5b bond with surrounding atoms and molecules and disappear can be slowed down, so that the processed gas G2 containing a high concentration of radicals can be discharged from the gas outlet 12.

[0052] In addition, depending on the raw material that is the radical source, there are some that produce products by combining radicals with atoms or molecules, and then decompose again to release radicals. For example, ozone (O 3 ) is converted again into oxygen radical O( 3 P). Equation (2) is presented again below. O 3 → O( 3 P) + O 2 ...(2)

[0053] This formula (2) corresponds to the reverse reaction of the formula (1) above. In other words, the higher the temperature, the more likely this reaction will proceed. In other words, even if a radical is once generated and disappears by bonding with surrounding atoms or molecules, the probability of it re-radicalizing can be increased. As a result, depending on the raw material that serves as the radical source, the effect of further increasing the concentration of radicals contained in the processed gas G2 can be obtained.

[0054] As a secondary effect, the heated post-processing gas G2 is blown onto the target surface 40a, which is the surface of the object 40 to be processed, and therefore the temperature of the target surface 40a can be increased. Since the reaction rate of radicals on the target surface 40a increases as the temperature increases, a secondary effect of promoting the reaction rate on the target surface 40a can be expected by increasing the temperature of the post-processing gas G2.

[0055] The above will be described later with reference to examples.

[0056] <<Variation>> Various modifications are possible to the structure of the gas supply device 1. Examples of these configurations will be described below.

[0057] <1> Compared to the gas supply device 1 shown in FIG. 1, each of the gas supply devices 1 shown in FIGS. 5 to 9 has a different method for heating the source gas G1, but the rest is common to both.

[0058] 5 includes a pipe 52 connected to a housing 3, and a heating unit 51 is provided to cover a part of the outer periphery of the pipe 52. Preferably, a heat-insulating member 53 having a heat-insulating function is disposed around the wall of the pipe 52. This allows the pipe 52 to have a heat-insulating function. The material of the heat-insulating member 53 can be, for example, a material with high heat-insulating properties, such as rock wool or glass wool.

[0059] In order to ensure heat retention for the pipe 52, the pipe 52 may have a double pipe structure, and a member having low thermal conductivity such as an air layer or a vacuum layer may be interposed between the inside of the pipe 52 (the region through which the source gas G1 flows) and the outside of the pipe 52. In this case, an air layer or a vacuum layer serving as a heat retention member 53 is disposed around the inner pipe of the pipe 52, which is the region through which the source gas G1 flows.

[0060] In the case of the gas supply device 1 shown in Fig. 5, the raw material gas G1 flows in from a gas inlet 11 which is an opening at one end of a pipe 52. The internal space of the pipe 52 and the internal space of the housing 3 form a gas flow path 10. The raw material gas G1 is heated and heated by a heating unit 51 while passing through the pipe 52, and is guided to the light irradiation region 5b in the housing 3. By arranging a heat-retaining member 53 around the periphery of the wall of the pipe 52, the rate at which the temperature of the heated raw material gas G1 decreases before it reaches the light irradiation region 5b is suppressed.

[0061] Incidentally, a heating unit 51 may be provided in a pipe 52 as in the gas supply device 1 shown in FIG.

[0062] As shown in Fig. 7, when the heating unit 51 is a light source that emits light L2 for heating, the raw material gas G1 flowing through the pipe 52 may be heated by irradiating the light L2 from the heating unit 51 arranged outside the pipe 52. In this case, the raw material gas G1 may be indirectly heated by heating the pipe 52 itself. Also, as shown in Fig. 8, the raw material gas G1 flowing upstream of the light irradiation region 5b in the case 3 may be heated by irradiating the light L2 from the heating unit 51 arranged outside the case 3.

[0063] In the embodiment shown in Figures 5 and 6, if the length of the housing 3 in the direction d1 upstream of the light irradiation region 5b is long, the heating section 51 may be arranged inside or outside the housing 3.

[0064] As shown in Fig. 9, raw material gases (G1a, G1b) may be flowed in from a plurality of systems via a pipe 52. Here, the raw material gas G1b is a gas having a higher temperature than the raw material gas G1a. The gas supply device 1 shown in Fig. 9 includes a gas inlet 11a through which the raw material gas G1a flows in and a gas inlet 11b through which the raw material gas G1b flows in, and a heating unit 51 is formed by a gas mixing region in the pipe 52 where the raw material gas G1a is mixed with the raw material gas G1b.

[0065] <2> In each of the above-described embodiments, the gas flow passage 10 may have a flow region (narrow portion) at the end portion on the gas outlet 12 side where the flow passage cross-sectional area is smaller than that at a position closer to the gas inlet 11 (i.e., the upstream side). For example, the gas supply device 1 shown in Fig. 10 has a narrow portion 13 at the end portion on the gas outlet 12 side where the flow passage cross-sectional area is continuously reduced.

[0066] As described above, the raw material gas G1 flowing through the gas flow passage 10 becomes the processed gas G2 containing radicals by being irradiated with the ultraviolet light L1 from the light source 5. When the processed gas G2 reaches the narrow portion 13, the flow rate of the processed gas G2 increases while flowing through the narrow portion 13, and the processed gas G2 advances toward the gas outlet 12, and is then discharged from the gas outlet 12 toward the target object 40.

[0067] As described above with reference to formula (3), oxygen radicals (O( 3 P)) is surrounded by oxygen gas (O 2 ) reacts with it to produce ozone (O 3 ) is produced. When this reaction occurs, O( 3 P) concentration decreases.

[0068] However, according to the above configuration, the flow rate of the processed gas G2 is increased when it is discharged from the gas outlet 12, so that the processed gas G2 can reach the surface (target surface 40a) of the target object 40 within the time in which the reaction of the above formula (3) does not proceed sufficiently. As a result, the processed gas G2 containing a high concentration of radicals can be sprayed onto the target surface 40a.

[0069] The configuration of the gas supply device 1 including the narrow portion 13 on the gas outlet port 12 side can also be appropriately applied to the following modified examples.

[0070] <3> In each of the above embodiments, the gas flow passage 10 is formed in the area surrounded by the light-emitting surface 5a. However, the gas flow passage 10 may be formed between the light-emitting surface 5a and the housing 3. For example, in the gas supply device 1 shown in FIG. 11, the light source 5 disposed in the housing 3 is disposed so that its light-emitting surface 5a is surrounded by the wall surface of the housing 3. That is, the raw material gas G1 flows through the gas flow passage 10 formed outside the light source 5, and the light irradiation area 5b is formed outside the light source 5. In this case, the first electrode 31 is formed in a mesh shape or a line shape so as not to hinder the ultraviolet light L1 from being emitted to the outside of the light-emitting tube 21.

[0071] In gas supply device 1 in an embodiment in which light irradiation region 5b is formed outside light source 5, light source 5 is not limited to an excimer lamp having a so-called "double tube structure" as exemplified in FIG. 2 and FIG.

[0072] For example, Fig. 12 is a schematic cross-sectional view of an excimer lamp having a so-called "single-tube structure" as the light source 5, cut along a plane defined by directions d2 and d3. The light source 5 shown in Fig. 12 has one arc tube 21, unlike the light source 5 shown in Figs. 2 and 3. The arc tube 21 is sealed (not shown) at its end in the longitudinal direction, i.e., in direction d1, and a light-emitting gas 23G is enclosed in the inner space. A second electrode 32 is disposed inside (inside) the arc tube 21, and a mesh-shaped or linear first electrode 31 is disposed on the outer wall surface of the arc tube 21.

[0073] As another example, Fig. 13 is a cross-sectional view, which is diagrammatically illustrated following Fig. 12, in the case where an excimer lamp having a so-called "flat tube structure" is used as the light source 5. The light source 5 shown in Fig. 13 has one arc tube 21 having a rectangular shape when viewed in the longitudinal direction, i.e., in the direction d1. A first electrode 31 is disposed on one outer surface of the arc tube 21, and a second electrode 32 is disposed 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, at least the electrode located on the gas passage 10 side has a mesh shape (mesh shape) or a line shape so as not to impede the emission of the ultraviolet light L1 to the outside of the arc tube 21.

[0074] In the light source 5 shown in FIG. 12 and FIG. 13, the shape when cut along a plane formed by the direction d2 and the direction d3 is not limited to a circle or a rectangle, and various shapes may be adopted.

[0075] <4> The gas supply device 1 may include a plurality of light sources 5. For example, the gas supply device 1 shown in Fig. 14 includes four light sources 5 having light-emitting surfaces 5a extending along the direction d1, and a light irradiation region 5b is formed in a region sandwiched between the light sources 5. In addition, a heating unit 51 is provided inside the housing 3, upstream of the light irradiation region 5b. Other elements are the same as those in the above-mentioned embodiment, and therefore description thereof will be omitted.

[0076] 1 may be realized by forming the light irradiation region 5b in the region sandwiched between the plurality of light sources 5. The same applies to the other embodiments.

[0077] <5> In each of the above embodiments, the light source 5 included in the gas supply device 1 has been described as having the light-emitting surface 5a extending in the direction d1 from the gas inlet 11 toward the gas outlet 12 as the longitudinal direction. However, the present invention is not limited to such a structure.

[0078] For example, the light source 5 of the gas supply device 1 shown in FIG. 15 has a shape extending in the direction d2 as a longitudinal direction. The gas inlet 11 is configured as an opening extending in the direction d2 on the surface of the housing 3 opposite to the target 40. The raw material gas G1 flowing in from the gas inlet 11, which is opened and extended in the direction d2, travels in the directions d1 and d3, is irradiated with ultraviolet light L1, and then is discharged from the gas outlet 12. The gas outlet 12 is configured as an opening extending in the direction d2 on the surface of the housing 3 facing the target 40. As in each of the above embodiments, the gas supply device 1 includes a heating unit 51 at a position upstream of the light irradiation region 5b irradiated with ultraviolet light L1 from the light source 5.

[0079] Even in this configuration, the source gas G1 is introduced to the light irradiation region 5b in a high temperature state, so that the processed gas G2 containing radicals at a high concentration can be discharged from the gas outlet 12.

[0080] In each of the above-described embodiments, the light source 5 may be shaped to extend in the direction d2 as the longitudinal direction, and the gas inlet 11 and the gas outlet 12 may each be configured as an opening extending in the direction d2.

[0081] <6> In each of the above-described embodiments, a heating section (corresponding to a "second heating section") for heating the raw gas G1 or the treated gas G2 flowing through the light irradiation region 5b may be provided in addition to the heating section 51. For example, the gas supply device 1 shown in FIG. 16 has a heating section 55 made of a fuel rod or the like installed in a region of the gas flow passage 10 corresponding to the location where the light irradiation region 5b is formed. This allows the temperature of the treated gas G2 immediately before it flows out of the gas outlet 12 to be further increased, so that the treated gas G2 can contain a high concentration of radicals.

[0082] <7> The gas supply device 1 may be realized by mutually applying the configurations of the above-described embodiments.

[0083] "verification" The fact that the gas supply device 1 causes the treated gas G2 discharged from the gas outlet 12 to contain a high concentration of radicals was verified by simulation.

[0084] 17 is a cross-sectional view showing a model of a gas supply device used in the simulation. The gas supply device model 100 includes a light source 5 having a light-emitting surface 5a having a side shape of a cylinder having a length h1 of 50 mm in the direction d1, and a gas flow passage 10 in an area surrounded by the light-emitting surface 5a. The gas flow 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. The light source 5 is a Xe excimer lamp having a main peak wavelength of 172 nm.

[0085] The target object 40 had a circular shape with a radius r1 of 20 mm, and was placed so that its center was located on the central axis of the gas flow passage 10. The raw material gas G1 was a mixed gas of 99.5% nitrogen gas and 0.5% oxygen gas, and the humidity was 0%. The raw material gas G1 was introduced into the gas supply device model 100 from the gas inlet 11 at a flow rate of 30 L / min.

[0086] In Examples 1 to 3, the temperature of the raw material gas G1 introduced into the gas inlet 11 was set to 100°C, 150°C, and 200°C, respectively. In Comparative Example 1, the temperature of the raw material gas G1 introduced into the gas inlet 11 was set to room temperature (27°C). In the gas supply device model 100 shown in FIG. 17, the light emitting surface 5a, i.e., the light irradiation region 5b, is disposed immediately adjacent to the gas inlet 11 in the direction d1. Therefore, in order to simulate a state in which the raw material gas G1 is at a high temperature when it is introduced into the light irradiation region 5b, a case in which the raw material gas G1 having a high temperature in advance is introduced into the gas inlet 11 was set as Examples 1 to 3, respectively.

[0087] In other words, the high-temperature raw material gas G1 assumed in Examples 1 to 3 corresponds to the raw material gas G1 immediately before passing through the heating section 51 and being introduced into the light irradiation region 5b in the gas supply device 1 described above with reference to FIG.

[0088] The illuminance on the light-emitting surface 5a is 50 mW / cm 2 While irradiating the light irradiation region 5b in the gas flow passage 10 with ultraviolet light L1 from the light source 5, the source gas G1 set to each temperature (100°C, 150°C, 200°C, 27°C) was made to flow in from the gas inlet 11 at the above flow rate. Then, in both Example 1 and Comparative Example 1, oxygen radicals O( 3 The mean concentration of β-p-total ... was calculated.

[0089] The calculation results are shown in FIG. 18. According to FIG. 18, in any of the cases of Examples 1 to 3, the oxygen radicals O( 3 It was confirmed that the average concentration of oxygen radicals O(P) in the post-processing gas G2 increased by more than three times. In particular, according to Examples 2 and 3, which were set at 150° C. or higher, the average concentration of oxygen radicals O(P) in the post-processing gas G2 increased by more than three times compared to Comparative Example 1. 3 It was confirmed that the average concentration of radicals (P) in the processed gas G2 could be increased by more than four times. This shows that the concentration of radicals in the processed gas G2 can be increased by increasing the temperature of the raw material gas G1 at a position upstream of the light irradiation region 5b. [Explanation of symbols]

[0090] 1: Gas supply equipment 3: Housing 5:Light source 5a: Light emitting surface 5b: Light irradiation area 10: Gas flow passage 11: Gas inlet 11a: Gas inlet 11b: Gas inlet 12: Gas outlet 13: Narrow part 21: Arc tube 21a:Outer tube 21b: Inner tube 23G: Luminous gas 31:First electrode 32:Second electrode 33: Reflective material 40: Object 40a: Target surface 51: Heating section (first heating section) 52: Piping 53: Thermal insulation material 55: Heating section (second heating section) 100: Gas supply equipment model G1: Raw gas G1a: Source gas G1b: Raw material gas G2: Processed gas L1: Ultraviolet light

Claims

1. a gas inlet into which a source gas containing a source material serving as a radical source is introduced; a gas flow passage through which the raw material gas flows after being introduced from the gas inlet; a light source that emits ultraviolet light toward a light irradiation region in the gas flow passage; a first heating unit configured to increase a temperature of the source gas at a position closer to the gas inlet than the light irradiation region; a gas outlet for discharging a treated gas, which is the raw material gas that has been heated by the first heating section and irradiated with the ultraviolet light, to the outside of the gas flow passage; 2. A gas supply device comprising: a gas outlet arranged to face an object to be treated when the post-treatment gas is sprayed onto the object to be treated.

2. 2 . The gas supply device according to claim 1 , wherein the gas flow passage is covered with a heat retaining member at least at a position between the first heating section and the light irradiation area.

3. 3. The gas supply device according to claim 1, further comprising a plurality of the gas inlet ports through which a plurality of the source gases having different gas temperatures are introduced.

4. 4. The gas supply device according to claim 1, further comprising a second heating section for heating the raw material gas or the treated gas flowing through the light irradiation region.

5. 5. The gas supply device according to claim 1, wherein the ultraviolet light emitted from the light source exhibits a light intensity in a wavelength range of less than 230 nm.

6. 6. The gas supply device according to claim 1, wherein the ultraviolet light emitted from the light source has a main emission wavelength of less than 230 nm.

7. 7. The gas supply device according to claim 1, wherein the source material is a material containing oxygen atoms.

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