JP2011003463A - Excimer irradiating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excimer irradiating device capable of efficiently, uniformly and stably irradiating a flat irradiated body with an excimer laser beam, and capable of selectively irradiating any one of excimer laser beams having several kinds of wavelength by exchanging discharge gas to be used.SOLUTION: A discharge container 2 includes: a casing-like body 21 including a flow-in opening 211 and a flow-out opening 212 on side surfaces thereof and opened in any one of two surfaces crossing the thickness direction thereof; and a flat lid body 22 to be joined with the open surface. Since the lid body 22 is formed into a flat shape easy to be machined, the lid body 22 can be structured from a fluoride having high permeability relative to the excimer laser beam in a wide wavelength region. Discharge gas for generating the excimer laser beam having a wavelength corresponding to the detail of processing can be selectively supplied from a discharge gas supply device 9 into the discharge container 2 via the flow-in opening 211 of the body 21. The excimer laser beam generated inside the discharge container 2 is uniformly irradiated from the whole surface of the flat lid body 22.

Description

  The present invention relates to an excimer irradiation apparatus that is used for film formation, dry cleaning, surface activation treatment, soft ashing, or the like in semiconductor manufacturing, and irradiates ultraviolet rays (excimer light) by high frequency discharge.

  Excimer as a light source of excimer light used for dry cleaning, surface activation treatment and soft ashing in the field of semiconductor manufacturing technology, ozone generation, water and air pollution purification and ultrapure water production in the field of environmental technology An excimer irradiation apparatus provided with a lamp is used.

  The excimer lamp irradiates an object to be treated with ultraviolet rays having a single wavelength such as 126 nm, 146 nm, 172 nm, 193 nm, 222 nm, or 308 nm (hereinafter referred to as “excimer light”) according to the type of discharge gas.

  Conventional excimer irradiation apparatuses generally include a tube-shaped excimer lamp (tube-type excimer lamp) (see, for example, Patent Document 1 or 2). The tube-type excimer lamp is composed of a mainly cylindrical discharge vessel made of quartz, an external electrode disposed on the outside thereof, and a quartz tube for protecting the external electrode. Furthermore, the space between the discharge vessel and the quartz tube is purged with nitrogen gas.

JP 2001-185089 A JP 2002-343306 A

  However, the conventional tube-type excimer lamp irradiates excimer light from the entire outer periphery of the cylindrical discharge vessel. For this reason, the distance from the outer peripheral surface of the cylindrical discharge vessel to the planar irradiated object changes according to the curvature of the outer peripheral surface, and is generated by an excimer lamp with respect to a flat irradiated object such as a silicon wafer. Only a part of the excimer light is irradiated and the processing efficiency is low. In addition, excimer light has low permeability in the atmosphere, and oxygen in the air that is about 8 mm or more away from the outer peripheral surface of the discharge vessel cannot be sufficiently changed to ozone, excited oxygen atoms, OH radicals, or O radicals. . Therefore, for example, when the irradiated object is a wafer on which a film is formed, some organic compounds that are sufficiently close to the outer peripheral surface are decomposed, but as the distance from the outer peripheral surface becomes longer, the organic compounds are It cannot be decomposed sufficiently.

  In addition, in the discharge vessel made of quartz, the wavelength of highly transmissive excimer light is limited, and the usage application is limited. For example, excimer light having a wavelength of 172 nm or less has low transmittance with respect to synthetic quartz, which is a material of the discharge vessel, and cannot irradiate the irradiated object with sufficient photon energy. For this reason, in the conventional excimer irradiation apparatus, the processable object and process content which can be processed are limited, and there also exists a problem which cannot respond to the process object itself and the change of the process content with respect to a process object.

  An object of the present invention is to irradiate excimer light efficiently and uniformly on a planar irradiated object, and excimer light of a plurality of types of wavelengths by exchanging discharge gas used. An object of the present invention is to provide an excimer irradiation apparatus capable of selectively irradiating any one of them.

  The excimer irradiation apparatus according to the present invention includes a discharge vessel, a window-side electrode layer, a back-side electrode layer, a power supply unit, and a discharge gas supply unit. The discharge vessel includes a main body and a lid. The main body includes a discharge gas inlet and an outlet and is a casing having one of two parallel planes orthogonal to the thickness direction as an open surface. The lid body has a flat plate shape made of a material that transmits excimer light, and is joined to the main body so as to cover the open surface of the main body. The window-side electrode layer is, for example, a mesh electrode that is attached to the outer surface of the lid and transmits excimer light. The back-side electrode layer is disposed on the outer surface of the back surface facing the open surface of the main body. The power supply means applies a high frequency voltage between the window side electrode layer and the back side electrode layer. The discharge gas supply means supplies the discharge gas into the discharge vessel from the inlet of the main body.

  In this configuration, when a high frequency voltage is applied between the window-side electrode layer and the back-side electrode layer from the power supply means while supplying the discharge gas into the discharge container by the discharge gas supply means, the discharge gas in the discharge container Generates excimer light of a wavelength corresponding to the type. Excimer light generated in the discharge vessel is uniformly distributed over the entire surface of the flat lid disposed on one of two parallel planes orthogonal to the thickness direction of the discharge vessel toward the irradiated object. The light passes through the window-side electrode layer disposed outside the lid, and is irradiated on the irradiated object.

  Since the lid of the discharge vessel has a flat plate shape, it is not necessary to consider workability as a material, and the material can be selected exclusively considering only the excimer light transmittance. The discharge vessel is opened to the outside through an inlet and an outlet, and a discharge gas corresponding to the required excimer wavelength can be selectively supplied into the discharge vessel. Accordingly, the lid is made of a material having high transparency for excimer light of each wavelength in a wide range, and any one of a plurality of types of discharge gases having different wavelengths of generated excimer light is selectively supplied into the discharge vessel. Thus, excimer light of a plurality of types of wavelengths is selectively irradiated.

  In this configuration, it is preferable to use a fluoride such as magnesium fluoride, lithium fluoride, or calcium fluoride as a material for the lid of the discharge vessel. These fluorides are not suitable for cutting or the like, but can be easily formed into a flat plate shape, have high light transmittance over a relatively wide band in the ultraviolet region, and can be applied to many kinds of discharge gases.

  In addition, it is preferable that at least the back surface of the main body of the discharge vessel facing the open surface has light shielding properties, or the back surface side electrode has light shielding properties. Excimer light can be prevented from being emitted from the back to the outside, and the object can be efficiently irradiated with excimer light via the lid.

  Further, an electrode side window member that is disposed in close contact with the outer surface of the window side electrode layer and transmits excimer light, and an irradiated body side that is disposed with a predetermined gap outside the electrode side window member and transmits excimer light. When the window member is provided, it is preferable that a filter that transmits excimer light is provided outside the irradiated object side window member in an oxygen-free state between the outer surface of the irradiated object side window member and detachable. It is possible to prevent the irradiated object side window member from being soiled by dust generated on the surface of the irradiated object irradiated with the excimer light. In addition, excimer light irradiation efficiency to the irradiated object can be recovered by exchanging the filter. Note that the oxygen-free state includes a vacuum state and a state replaced with an inert gas.

  In this case, it is preferable to provide an inert gas supply means for circulating an inert gas in the gap between the electrode side window member and the irradiated object side window member. The heat generated in the discharge vessel when excimer light is generated is taken away by the inert gas flowing through the gap, and the discharge vessel can be cooled.

  In addition, it is preferable to include a sensor that detects a fluorescence state of a surface other than the window surface in the discharge vessel, and a control unit that detects an irradiation state of the excimer light according to a detection signal of the sensor. The generation state of excimer light in the discharge vessel can be easily confirmed. In this case, the control unit may control the output of the power supply unit according to the detection signal of the sensor.

  Furthermore, the temperature of the discharge vessel can be controlled more accurately by disposing the fluid cooling means outside the back electrode layer.

  According to the present invention, it is possible to irradiate excimer light efficiently and uniformly on a planar object to be irradiated, and excimer light having a plurality of types of wavelengths can be obtained by exchanging discharge gas used. Either can be selectively irradiated.

It is sectional drawing of the excimer irradiation apparatus which concerns on embodiment of this invention. It is sectional drawing of the discharge vessel with which the excimer irradiation apparatus is equipped. It is an expanded sectional view of the principal part of the same excimer irradiation apparatus. It is an expanded sectional view of the principal part of the excimer irradiation apparatus which concerns on another embodiment of this invention.

  As shown in FIG. 1, an excimer irradiation apparatus 1 according to an embodiment of the present invention irradiates excimer light, which is ultraviolet light, on an irradiated object that is conveyed in a horizontal direction in a lower chamber (not shown). For this reason, the excimer irradiation apparatus 1 includes a discharge vessel 2, a window side electrode layer 3, a back side electrode layer 4, a power supply device 5, an electrode side window member 6, an irradiated object side window member 7, a filter 8, and a discharge gas supply device 9. , An inert gas supply device 10, a frame 20, a cover 30, a sensor 40, a control unit 50, and a display 60. The discharge vessel 2 includes a main body 21 and a lid body 22.

  As shown in FIG. 2, the main body 21 is a housing in which one of two surfaces orthogonal to the thickness direction is an open surface 21A, and an inflow port 211 and an outflow port 212 are formed on the side surfaces. Yes. For this reason, the main body 21 is made of a dielectric material such as quartz or synthetic quartz having a thickness of about 1 to 8 mm in consideration of workability. The discharge gas supply device 9 is connected to the inflow port 211. The outflow port 212 is provided with a pressure adjusting device 213. The pressure adjusting device 213 changes the opening state of the outlet 212 to adjust the pressure inside the discharge vessel 2 to a pressure suitable for excimer light irradiation (for example, usually about 1 to 110 KPa). The arrangement positions and the number of the inlets 211 and outlets 212 on the side surface of the main body 21 are determined according to the flow state of the discharge gas.

  The lid 22 has a flat plate shape made of a material that transmits excimer light, and is joined to the main body so as to cover the open surface 21 </ b> A of the main body 21. Since the lid 22 has a flat plate shape, it is not necessary to consider workability as a material, and considering only excimer light transmittance, for example, fluoride such as magnesium fluoride, lithium fluoride, calcium fluoride, etc. The material is a monster. These fluorides are not suitable for cutting or the like, but can be easily formed into a flat plate shape, and have high light transmittance over a relatively wide band in the ultraviolet region.

  The discharge vessel 2 is opened to the outside through the inlet 211 and the outlet 212 of the main body 21. For this reason, airtightness is not required for the joint portion between the main body 21 and the lid body 22. The discharge vessel 2 can be formed to have a length and width of 3 to 50 cm and a height of about 1 to 2 cm, for example.

  As shown in FIG. 3, the window-side electrode layer 3 is attached to the outer surface of the lid body 22. The window-side electrode layer 3 is formed in a mesh shape using stainless steel, aluminum, aluminum alloy, copper, copper oxide, or an alloy thereof as a material. The window-side electrode layer 3 is not limited to a mesh shape, but needs to have openings uniformly over the entire surface of the lid 22. The excimer light transmitted through the lid 22 passes through the opening of the window-side electrode layer 3 and travels toward the irradiated body.

  As shown in FIG. 3, the back-side electrode layer 4 is attached to the outer surface of the back surface 21 </ b> B of the main body 21 (the surface opposite to the open surface 21 </ b> A among the two surfaces perpendicular to the thickness direction of the main body 21). Is done. The back-side electrode layer 4 is composed of a mesh electrode 42 made of stainless steel, aluminum, an aluminum alloy, copper, copper oxide, or an alloy thereof, and a plate electrode 43 of an aluminum thin plate disposed on the upper side. The plate electrode 43 is a light shielding member of the present invention that shields the back surface (upper surface) side of the discharge vessel 2 and reflects excimer light generated in the discharge vessel 2 toward the front surface (lower surface) side of the discharge vessel 2. The back side electrode layer 4 is uniformly arranged on the entire surface of the back side 21 </ b> B so that excimer light is uniformly discharged at each part in the discharge vessel 2 and the irradiation distribution on the lid 22 is uniform.

  The upper surface of the back electrode layer 4 is covered with a back member 41. The back member 41 presses and fixes the discharge vessel 2 toward the frame 20. As shown in FIG. 1, a through-hole 4 </ b> A is formed in the back side electrode layer 4. The back member 41 has a plate shape made of quartz or synthetic quartz. Part of the excimer light generated in the discharge vessel 2 passes through the through hole 4A and is guided to the back member 41. The back member 41 fluoresces by excimer light leaking from the through hole 4A.

  In the case where the back electrode 4 is composed of only the mesh electrode 42, the back member 41 can be composed of a light shielding material and can be used as the light shielding member of the present invention. In this case, a through hole is formed at a position facing the through hole 4 </ b> A of the back member 41.

  As shown in FIG. 4, by forming the back-side electrode layer 4 in a plate shape, it is possible to prevent the excimer light traveling toward the back surface 21 </ b> B from leaking outside the discharge vessel 2 without providing a separate back surface member 41. . In this case, the back side electrode layer 4 corresponds to the light shielding member of the present invention. Further, when the back surface 21B has light shielding properties, the back electrode layer 4 does not necessarily have a plate shape.

  The power supply device 5 shown in FIG. 1 applies a high frequency voltage between the window side electrode layer 3 and the back side electrode layer 4. By applying a high frequency voltage between the window-side electrode layer 3 and the back-side electrode layer 4, the discharge gas 11 generates excimer light in the discharge vessel 2.

  As shown in FIG. 1, the electrode-side window member 6 is disposed with the entire upper surface in close contact with the window-side electrode layer 3. The electrode side window member 6 is formed in a plate shape using, for example, magnesium fluoride or calcium fluoride excellent in light transmittance.

  The irradiated object-side window member 7 is fitted into the opening 20 </ b> A of the frame 20 from above and is mounted via a packing 62. The irradiated object side window member 7 is formed in a plate shape using, for example, magnesium fluoride or calcium fluoride excellent in light transmittance. A support body 61 made of a tubular body having a rectangular cross section is placed on the periphery of the upper surface of the irradiated object side window member 7. The electrode side window member 6 is placed on the upper surface of the support 61. A gap 12 is formed above the irradiated object side window member 7 by the support 61 and the bottom surface of the electrode side window member 6.

  On the upper surface of the frame 20, a plurality of support columns 63 are attached to the outer edge portion of the opening 20A. A screw hole is formed in the column 63 from the upper surface toward the inside. A fixing screw 65 penetrating the back member 41 vertically is screwed into the screw hole. A spring 64 is fitted on the upper portion of the screw portion of the fixing screw 65. The spring 64 presses the back member 41 downward by being compressed between the head of the fixing screw 65 and the back member 41. Due to the pressing force of the spring 64, the irradiated object-side window member 7, the support 61, the electrode-side window member 6, the window-side electrode layer 3, the discharge vessel 2, the back-side electrode layer 4 and the back-side member 41 are placed on the frame 20 from below. They are stacked and fixed in order.

  The filter 8 is formed in a thin plate shape using magnesium fluoride, calcium fluoride, or the like excellent in light transmittance as a material. The filter 8 is detachably disposed, for example, with the entire surface in close contact with the bottom surface of the irradiated object side window member 7 via a fixing screw. The dust generated on the surface of the irradiated body adheres to the filter 8 and does not adhere to the irradiated body-side member and the electrode-side window member 6. By exchanging or cleaning only the filter 8, the excimer light irradiation efficiency due to the adhesion of dust can be recovered, and the running cost of the excimer irradiation apparatus 1 can be reduced.

  In an environment in which the space between the excimer irradiation apparatus 1 and the chamber disposed therebelow is maintained in an oxygen-free state such as a vacuum state or a state where it is replaced with an inert gas, a filter 8 is provided on the upper surface of the chamber. Can be installed. When the filter 8 is attached to the upper surface of the chamber, it is not necessary to fix the filter 8 to the upper surface of the chamber via a fixing member, and the filter 8 can be replaced simply by removing the excimer irradiation device 1 from above the chamber. 8 can be simplified. If the bottom surface of the irradiated object side window member 7 is not soiled according to the processing content, the filter 8 can be omitted.

  The discharge gas supply device 9 is a discharge gas supply means of the present invention, and supplies discharge gas into the discharge vessel 2 from an inlet 211 formed in the main body 21 of the discharge vessel 2. The discharge gas supplied into the discharge vessel 2 from the discharge gas supply device 9 is selectively changed according to the wavelength of excimer light required for processing the object to be processed. It should be noted that the inflow port 211 and the outflow port 212 are connected to the discharge gas supply device 9, and the discharge gas supply device 9 supplies the discharge gas so that the discharge vessel 2 has a pressure suitable for the generation of excimer light. The pressure adjusting device 213 can be omitted by changing the amount.

  Since the lid 22 has a flat plate shape, it is not necessary to consider workability as a material, and the material can be selected exclusively considering only the excimer light transmittance. The discharge vessel 2 is opened to the outside through an inlet 211 and an outlet 212, and a discharge gas corresponding to the required wavelength of excimer light can be selectively supplied into the discharge vessel 2.

  Therefore, by selecting a material having high excimer light transmittance over a wide range of wavelengths as the material of the lid 22, any one of a plurality of types of discharge gases having different wavelengths of excimer light generated can be selectively used. It is possible to selectively irradiate excimer light having a plurality of types of wavelengths supplied into the discharge vessel 2.

  The inert gas supply device 10 is an inert gas supply means of the present invention, and introduces an inert gas such as nitrogen gas as an example through a duct 9 </ b> A arranged on the entire outer periphery of the support 61. . Holes are formed in the horizontal direction at predetermined intervals on the inner surface of the duct 9A and the inner and outer surfaces of the support 61. The inert gas discharged from the hole of the duct 9 </ b> A is introduced into the gap 12 through the inside of the support 61. The gap 12 is purged with an inert gas and air is excluded. Further, while the excimer irradiation apparatus 1 irradiates the object to be irradiated with excimer light, the inert gas is circulated in the gap 12 by continuing the supply of the inert gas to the gap 12 by the gas supply apparatus 10. The discharge vessel 2 is cooled via the electrode side window member 6.

  In addition, it is preferable to provide a support means for supporting the irradiated object side window member 7 with respect to the electrode side window member 6 along the normal direction of the lid 22 so as to be displaceable. The width of the gap 12 in the normal direction of the lid 22 can be adjusted, and the temperature can be controlled by adjusting the flow rate of the inert gas in the gap 12.

  The discharge vessel 2, the window-side electrode layer 3, the back-side electrode layer 4, the power supply device 5, the electrode-side window member 6, and the back member 41 are arranged in a state of being placed on the upper surface of the frame 20 and covered with the cover 30. Yes. The cover 30 has a window 30A and a hole 30B formed on the upper surface. The window portion 30A is disposed at a position facing the through hole 4A. When the main body 2 is formed of a material having translucency, a part of the excimer light generated in the discharge vessel 2 may be exposed upward via the through hole 4A. The hole 30B is formed at a position facing the through hole 41B. A wiring tube 70 is inserted into the hole 30B. The lower end portion of the wiring pipe 70 penetrates the through hole 41B. In the wiring tube 70, a power supply line that connects the power supply device 5 to the window-side electrode layer 3 and the back-side electrode layer 4 is inserted.

  The sensor 40 is disposed outside the window 30 </ b> A of the cover 30. The sensor 40 receives the fluorescence of the excimer light leaked from the through-hole 4 </ b> A in the back member 41 through the window portion 30 </ b> A and outputs a detection signal having a level corresponding to the amount of received light to the control unit 50. When the side surface of the discharge vessel 2 is not covered, the sensor 40 may be arranged to face the side surface of the discharge vessel 2.

  The control unit 50 controls the lighting state of the display device 60 based on the detection signal output from the sensor 40. The control unit 50 turns on the display 60 when a detection signal of a predetermined level or less is input from the sensor 40. By visually confirming the lighting state of the display device 60, it can be confirmed whether or not excimer light is irradiated from the excimer irradiation device 1 to the irradiated object.

  Further, the control unit 50 controls the output of the power supply device 5 based on the level of the detection signal. The control unit 50 outputs control data corresponding to the level of the detection signal to the power supply device 5. For example, the control unit 40 compares the level of the detection signal with a reference level, and outputs control data so as to raise or lower the high-frequency voltage of the drive circuit according to the comparison result. The output power supply device 5 applies a high-frequency voltage having a frequency according to the control data between the window-side electrode layer 3 and the back-side electrode layer 4. The output of the power supply device 5 can be feedback-controlled based on the state of excimer light generation in the discharge vessel 2, and excimer light having a light amount suitable for processing on the irradiated object can be stably irradiated.

  Note that the lighting control of the display device 60 and the output control of the power supply device 5 by the control unit 50 are not necessarily essential, and either one or both of them can be omitted.

  By applying a high frequency voltage between the window-side electrode layer 3 and the back-side electrode layer 4 from the power supply device 5, silent discharge occurs in the discharge vessel 2, and uniform and sufficient excimer light is emitted from the lid 22. . The power supply device 5 applies a high frequency voltage at a frequency of 1 MHz to 20 MHz, for example. Thereby, luminous efficiency and thermal efficiency can be improved, and power consumption can be reduced. A more preferable frequency of the high-frequency voltage is 1 MHz to 4 MHz. The high frequency voltage at this time is preferably 1 to 20 kV. When the high-frequency voltage is less than 1 kV, uniform and sufficient discharge does not occur between the external electrode 6 and the back-side electrode layer 4, and sufficient excimer light cannot be uniformly irradiated from the lid 22.

  On the other hand, when the high frequency voltage exceeds 20 kV, the excimer irradiation amount is saturated, and sufficient light emission efficiency cannot be obtained with respect to the input power, and the power consumption increases, resulting in poor efficiency. The high frequency voltage has different lamp capacitances at the start of discharge and discharge. For this reason, for example, the power supply device 5 is provided with a function of switching between the applied frequency at the start of discharge and the applied frequency at the time of discharge, and the output of the power supply device 5 is boosted by a transformer so that the window-side electrode layer 3 and the back-side electrode layer 4 You may make it apply in between.

  The excimer irradiation apparatus 1 can uniformly irradiate excimer light from the large-sized cover 22. Therefore, it is possible to irradiate the irradiated object with a large amount of excimer light at a time. Further, excimer light is uniformly irradiated from the entire surface of the lid 22. For this reason, by making the interval between the lid 22 and the irradiated body constant, it is possible to efficiently irradiate the irradiated body with excimer light having a uniform intensity, and the irradiated body has an excimer light with little attenuation. Is irradiated over a large area, and surface modification treatment and organic compound decomposition treatment are efficiently performed.

  The description of the above-described embodiment is an example in all respects and should be considered as not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

1-Excimer irradiation device 2-Discharge vessel 3-Window side electrode layer 4-Back side electrode layer 5-Power supply device (power supply means)
6-electrode side window member 7-irradiated object side window member 8-filter 9-discharge gas supply device (discharge gas supply means)
10-Inert gas supply device (inert gas supply means)
21-main body 22-lid body 211-inlet 212-outlet

Claims (10)

A main body having an inflow port and an outflow port for discharge gas and having one surface of two parallel planes orthogonal to the thickness direction as an open surface;
A flat body made of a material that transmits excimer light, and a lid joined to the main body so as to cover the open surface of the main body,
A window-side electrode layer disposed on the outer surface of the open surface and transmitting excimer light;
A back-side electrode layer disposed on the outer surface of the back surface facing the window surface in the discharge vessel;
Power supply means for applying a high-frequency voltage between the window-side electrode layer and the back-side electrode layer;
A discharge gas supply means for supplying a discharge gas from the inlet;
Excimer irradiation device with   The excimer irradiation apparatus according to claim 1, wherein the lid is made of fluoride.   The excimer irradiation apparatus according to claim 1, wherein a back surface of the main body facing the open surface has a light shielding property.   The excimer irradiation apparatus of Claim 1 or 2 which has arrange | positioned the light-shielding member in the whole surface of the outer surface of the back facing the said open surface in the said main body. An electrode-side window member that is disposed in close contact with the outer surface of the window-side electrode layer and transmits excimer light;
An irradiated-object-side window member that is disposed outside the electrode-side window member with a predetermined gap and transmits excimer light;
An inert gas supply means for circulating an inert gas in the gap;
The excimer irradiation apparatus according to any one of claims 1 to 4, further comprising:   The excimer irradiation apparatus according to claim 5, wherein a filter that transmits ultraviolet rays is detachably provided outside the irradiation object side window member so as to be in an oxygen-free state between the filter and the outer surface of the irradiation object side window member.   The excimer irradiation apparatus according to any one of claims 1 to 6, wherein the window-side electrode layer is a mesh electrode having a plurality of openings along a surface direction of the window surface.   The sensor according to claim 1, further comprising: a sensor that detects a fluorescence state of a surface other than the window surface in the discharge vessel; and a control unit that detects an irradiation state of the ultraviolet ray according to a detection signal of the sensor. Excimer irradiation apparatus described in 1.   The excimer irradiation apparatus according to claim 8, wherein the control unit controls an output of the power supply unit according to a detection signal of the sensor.   The excimer irradiation apparatus according to claim 1, wherein a fluid cooling means is disposed outside the back electrode layer.

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