JP4595556B2 - UV irradiation equipment - Google Patents

Description

  The present invention relates to an ultraviolet irradiation device including an excimer lamp. In particular, the present invention relates to an ultraviolet irradiation apparatus that measures the intensity of radiated light from an excimer lamp and confirms the lighting state of the excimer lamp based on the measurement result.

In the manufacturing process of a liquid crystal substrate or the like, the object to be processed is processed by causing active oxygen generated by dissociation of ozone generated by irradiating ultraviolet rays having a wavelength of 200 nm or less to oxygen to the substrate to be transported. ing. For example, a cleaning technique for removing organic substances adhering to the surface of a substrate has been put into practical use.
Conventionally, a low-pressure mercury lamp that emits vacuum ultraviolet rays having a wavelength of 185 nm is used as a lamp for performing such treatment.

  In recent years, instead of a low-pressure mercury lamp, it has a double-cylindrical structure in which a cylindrical outer tube is also coaxially arranged outside the cylindrical inner tube, and an outer electrode is arranged on the outer surface of the outer tube. An excimer lamp having a structure in which an inner electrode is disposed inside a tube and a space formed between the outer tube and the inner tube is used as a discharge space is used in the above-described processing (see Patent Document 1). In this excimer lamp, it is known that a vacuum ultraviolet ray having a peak at a wavelength of 172 nm is emitted by using, for example, xenon gas as a discharge gas for generating excimer discharge.

  On the other hand, the discharge vessel is not a double cylinder type, but the discharge vessel is formed of a single cylinder, an outer electrode is disposed on the outer surface of the cylinder, and the inner electrode is exposed and extends into the discharge space (single cylinder) An excimer lamp having a type is also disclosed (see Patent Document 2). This structure has an advantage that it is advantageous in terms of cost because it is easy to manufacture because there is no equivalent to the inner tube in the double cylindrical excimer lamp.

  When such an excimer lamp is lit in the air, the vacuum ultraviolet rays radiated from the excimer lamp react with oxygen in the air around the excimer lamp to generate ozone. Has a problem that the electrode is corroded by the generated ozone. Further, since the vacuum ultraviolet rays from the excimer lamp are absorbed by oxygen in the air, there is a problem that the substrate that is the object to be processed cannot be irradiated with the vacuum ultraviolet rays with high efficiency. For these reasons, when an excimer lamp is used, the excimer lamp is arranged in a housing having a window for taking out vacuum ultraviolet rays to constitute an ultraviolet irradiation device, and nitrogen gas or the like is not contained in the housing. Excimer lamps are lit in an inert atmosphere by introducing an active gas.

In such an ultraviolet irradiation device, since it is impossible to visually confirm whether or not the excimer lamp arranged in the housing is lit, a lighting confirmation means for confirming the lighting of the excimer lamp is provided. It is common.
Here, in order to confirm the lighting of the excimer lamp, as shown in FIG. 8, the ultraviolet light emitted from the lamp is converted into visible light by a phosphor, and the visible light is detected by a detecting means such as a photodiode. The use of a means for confirming the lighting state of an excimer lamp is disclosed (see Patent Document 3).

FIG. 8 is a cross-sectional view for explaining a conventional ultraviolet irradiation device.
In the ultraviolet irradiation device 700, a plurality of excimer lamps 80 are housed in a box-shaped housing 71. A light extraction window member 73 for extracting the vacuum ultraviolet light from the excimer lamp 80 to the outside is disposed in the opening 72 of the casing 71. A through hole 74 is formed in the upper surface of the casing 71 at a position above the excimer lamp 80, and a window member 75 for light detection that transmits visible light is disposed in the through hole 74.
A cooling block 90 for cooling the excimer lamp 80 is provided above the inside of the casing 71. A plurality of groove portions 91 for disposing excimer lamps are formed on the lower surface of the cooling block 90 so as to be spaced apart from each other, and an excimer lamp 80 is disposed for each groove portion 91. The cooling block 90 is provided with a light introduction hole 92 that passes through the cooling block 90 in the vertical direction and communicates with the groove portion 91 at a position directly below the light detection window member 75.
On the upper surface of the window member 75, a photodetector 77 including a light receiving portion 76 made of a silicon photodiode or the like is provided.
A phosphor layer 78 is provided on the outer surface of the excimer lamp 80 at a position immediately below the window member 75.

In such an ultraviolet irradiation device 700, the vacuum ultraviolet light emitted from the excimer lamp 80 is converted into visible light by the phosphor layer 78, and the visible light transmitted through the window member 75 is detected by the photodetector 77. Thus, the lighting of the excimer lamp 80 can be confirmed.
Japanese Patent No. 2854255 JP 2001-84966 A JP 2000-193799 A

  However, it has been found that it may not be possible to detect that the excimer lamp has been turned off even with the ultraviolet irradiation device as shown in FIG. The reason for this will be described below with reference to FIGS.

FIG. 9 shows a cross-sectional view in the longitudinal direction of an excimer lamp having a single cylindrical structure.
The excimer lamp 80 has a discharge vessel 81 made of one cylindrical body. The discharge vessel 81 is formed with sealing portions 83 (83a, 83b) in which metal foils 82 (82a, 82b) made of molybdenum are embedded at both ends. The inner electrode 84 has a coil portion 85 extending along the longitudinal direction of the discharge vessel 81 and straight portions 86 (86a, 86b) connected to both ends of the coil portion 85. The part 86 is connected. The other end of the metal foil 82 is connected to an external lead 87 (87a, 87b) protruding outward from the sealing portion 83. A power supply line 89 connected to the power supply device is connected to the external lead 87a, whereby power is supplied to the inner electrode 84 and the outer electrode 88, and an excimer discharge is formed by dielectric breakdown between both electrodes, and irradiation with vacuum ultraviolet rays is performed. Is done.

  However, when the excimer lamp shown in FIG. 9 is lit for a long time, the material constituting the inner electrode is sputtered by ion or electron collision and scattered in the discharge space, so that a part of the inner electrode is thinned and thinned. The part may be disconnected due to the temperature increasing with increasing current density. In this case, in a place electrically disconnected from the power supply line, the power supply is interrupted and the light is not turned on. In particular, the inner electrode on the power supply side has higher current density than the non-power supply side, and the temperature tends to rise, so it is easy to sputter. There is a high probability of breakage.

  However, as shown in FIG. 10, the excimer lamp 80 has a region (indicated by Y in FIG. 10) where the inner electrode 84 is electrically connected to the power feeding device when the inner electrode 84 is disconnected at a portion indicated by A. In the region), the lighting is still continued, but in the region where the inner electrode 84 is electrically disconnected from the power feeding device (the X region in FIG. 10), the lighting is not performed. In this case, if a photodetector is disposed at a position corresponding to the Y region, the phosphor layer is radiated from the Y region by the photodetector 77 even though the X region is not lit. Since the visible light converted by 78 is detected, the operator who handles the ultraviolet irradiation device misunderstands that the excimer lamp is lit normally, and cannot reliably detect the non-lighting in the X region. The problem arises.

  In view of the above, an object of the present invention is to provide an ultraviolet irradiation device that can reliably detect whether the excimer lamp is turned on or off in the ultraviolet irradiation device including the excimer lamp.

An ultraviolet irradiation device of the present invention is composed of a dielectric material that transmits ultraviolet light at least partially, a discharge vessel in which a discharge gas is filled in a discharge space, and a dielectric material that constitutes the discharge vessel. An ultraviolet irradiation device comprising: an excimer lamp having a pair of electrodes that are interposed and opposed; and a power feeding device that is electrically connected to each of the pair of electrodes and feeds power to the excimer lamp. , At least one of the electrodes is electrically connected to one end thereof, and in the effective light emitting region, the region closer to the other end of the electrode than one end of the electrode to which the power feeding device is connected A light guide that emits light emitted from the excimer lamp incident from one end and that is emitted from the other end, a light receiver that receives light emitted from the light guide, and measurement of the light receiver. Based on results Characterized in that it includes a lighting detection means for detecting the lighting state of the excimer lamp.
Furthermore, the ultraviolet irradiation device of the present invention is composed of a dielectric material that transmits ultraviolet light at least partially, a discharge vessel filled with a discharge gas in the discharge space therein, and a dielectric that constitutes the discharge vessel An ultraviolet irradiation device comprising: an excimer lamp having a pair of electrodes opposed to each other with a material interposed therebetween; and a power feeding device electrically connected to each of the pair of electrodes to feed power to the excimer lamp. The apparatus emits light from the excimer lamp incident from one end, which is electrically connected to both ends of at least one of the electrodes and arranged corresponding to a region near the center of the effective light emitting region. A light guide that emits the emitted light from the other end, a light receiving unit that receives the light emitted from the light guide, and a lighting detection that detects the lighting state of the excimer lamp based on the measurement result of the light receiving unit Ultraviolet irradiation apparatus characterized by and a stage.

  Furthermore, in the ultraviolet irradiation device of the present invention, any one of the electrodes is disposed in a discharge space in the discharge vessel, and an outer surface of a portion that discharges between at least the other electrode of the one electrode is , At least one end is covered with an inner tube made of a dielectric material open in the discharge space.

  According to the ultraviolet irradiation device of the present invention, one end provided corresponding to a region closer to the other end of the electrode than one end of the one electrode connected to the power feeding device in the effective light emitting region of the excimer lamp. A light guide unit that emits light emitted from the other end of the light guide unit, a light receiving unit that receives light emitted from the other end of the light guide unit, and a lighting detection unit connected to the light receiving unit. This ensures that the excimer lamp will not be turned on regardless of where the inner electrode breaks in any part of the effective light-emitting area that extends from the starting point on the power supply device side to the part corresponding to directly below the light guide. can do.

  In addition, by providing a power supply control mechanism that controls the power supply of the lighting power to the excimer lamp and a transport control mechanism that controls the operation of the transport mechanism, when the inner electrode is disconnected, the excimer lamp can be quickly turned on. While stopping the power supply, the conveyance of the substrate can be stopped. Thereby, unnecessary power supply of the lighting power to the excimer lamp is not continued, and there is no fear that the substrate cleaning process becomes incomplete.

[First Embodiment]
FIG. 1 shows a cross-sectional view of a first ultraviolet irradiation device of the present invention. FIG. 1A is a cross-sectional view of the ultraviolet irradiation device cut along a plane orthogonal to the tube axis of the excimer lamp. FIG. 1B is a cross-sectional view of the ultraviolet irradiation apparatus shown in FIG. 1A cut along the plane of the excimer lamp along a plane including the line MM ′.

In the ultraviolet irradiation apparatus 100, four excimer lamps 1 having a single cylindrical structure are housed in a box-shaped housing 11, and face a substrate 36 that is a target object disposed on a transport mechanism 35. Has been placed.
A light extraction window member 13 made of, for example, quartz glass for extracting vacuum ultraviolet light from the excimer lamp to the outside is disposed in the opening 12 of the housing 11. A through hole 14 is formed on the upper surface of the housing 11 at a position above the excimer lamp 1. The casing 11 is provided with an inflow hole 15 for introducing an inert gas into the casing on one side surface, and a discharge hole 16 for discharging the inert gas on the other side surface. The inside of the housing 11 is filled with an inert gas such as nitrogen, for example.

  A cooling block 20 in which a flow path (not shown) for circulating a cooling fluid for cooling the excimer lamp 1 is formed in the upper part of the housing 11. On the lower surface of the cooling block 20, four groove portions 201 each having a semicircular cross section having a diameter larger than the outer diameter of the excimer lamp 1 are formed apart from each other in a direction perpendicular to the paper surface, and along each of these groove portions 201. An excimer lamp 1 is arranged.

The excimer lamp 1 is composed of a tubular discharge vessel 2 as a whole, and a straight tube portion 21 filled with a discharge gas, and sealing portions 22 (22a, 22b) that hermetically seal the straight tube portion 21 at both ends thereof. Is formed. The discharge vessel 2 is made of, for example, synthetic quartz glass as a material that transmits vacuum ultraviolet light well.
Inside the discharge vessel 2, the inner electrode 3 is arranged so as to extend substantially at the center of the discharge vessel 2, and the outer electrode 4 is arranged in close contact with the outer surface of the discharge vessel 2. The inner electrode 3 is made of, for example, a tungsten wire, and includes a coil portion 31 formed in a coil shape, and linear portions 32 (32 a and 32 b) connected to both ends of the coil portion 31. The inner electrode 3 is bonded to the metal foil 5 (5a, 5b) at the sealing portions 22a, 22b, respectively, and the external lead 6 (6a, 6b) is further bonded to the metal foil 5.
An inner tube 7 made of a dielectric material is provided around the inner electrode 3 so as to cover the inner electrode 3, and the inner electrode 3 is inserted into the inner tube 7. The inner tube 7 is made of, for example, synthetic quartz glass and is covered outside of a portion that discharges at least between the inner electrode 3 and the outer electrode 4, and the end of the inner tube 7 is the end of the outer electrode 4. It extends beyond. The inner tube 7 is open at both ends in the discharge space and does not exist at both ends of the coil portion 31. Therefore, the inner electrode 3 is directly exposed to the discharge gas without being covered by the inner tube 7 at both ends of the coil portion 31 and a part of the linear portion 32. The inner tube 7 is fixed to the inside of the discharge vessel 2 by a ring-shaped support member 8 (8a, 8b) that is fitted to the inner tube 7 and fixed to the inner tube 7 by welding or adhesion.
The outer electrode 4 is a cylindrical mesh structure in which metal wires are formed in a net shape, and is arranged so as to cover the outer surface of the discharge vessel 2. For this reason, the vacuum ultraviolet light from the discharge vessel 2 is emitted through the mesh of the outer electrode 4. Note that the outer electrode 4 having a structure in which one metal wire is knitted seamlessly is advantageous in that the adhesion to the discharge vessel is increased.
In the discharge space formed inside the straight tube portion 21, excimer molecules are formed by discharge through a dielectric material, and as a discharge gas for emitting vacuum ultraviolet light from the excimer molecules, for example, xenon gas, A mixed gas of argon and chlorine is enclosed.
A power feeding device 17 is connected to the external lead 6 a and the outer electrode 4 by a power feeding line 18. As a result, the inner electrode 3 is electrically connected to the power feeding device 17 only at one end 321a through the metal foil 5a and the external lead 6a. Lighting power is supplied from the power supply device 17 to the inner electrode 3 and the outer electrode 4, and a discharge is generated between both electrodes through the discharge vessel 2 and the inner tube 7 that are dielectric materials, and excimer emission is generated in the discharge gas. Arise.

According to the ultraviolet irradiation device 100 of the form shown in FIG. 1, the cooling block 20 corresponds to a position directly below the through hole 14 of the housing 11 and is effective against the excimer lamp 1 (with the inner electrode 3 and One of the ends 321a of the inner electrode 3 is a region where excimer discharge is formed by facing the outer electrode 4 and is indicated by a Z line connecting the start point 41 and the end point 42 in FIG. Corresponding to the region closer to the other end 321b of the inner electrode 3 (the region indicated by the X-ray connecting the end point 42 and the intermediate point 43 in FIG. 1B), it penetrates the cooling block 20 in the vertical direction. Thus, a light guide unit 202 that communicates with the groove 201 and emits light emitted from the excimer lamp incident from one end from the other end is formed. Above the housing 11, in order to receive the light emitted from the other end of the light guide unit 202, the same number of light receiving units 25 as the excimer lamp 1 are connected to each light incident surface 251 at the other end of the light guide unit 202. It is placed facing each other.
In this way, the non-lighting of the excimer lamp is reliably detected regardless of the portion of the effective light emitting region that extends from the starting point 41 to the portion corresponding to the position immediately below the light guide 202. be able to. In particular, when the light guide unit 202 is provided in the vicinity of the end point 42 in the region indicated by the X-ray, the non-lighting of the excimer lamp is reliably detected no matter where the inner electrode 3 is disconnected in the region indicated by the Z-ray. This is preferable because it can be performed.

  The light receiving unit 25 has photosensitivity to the emitted light from the excimer lamp, and has a function of outputting a voltage signal by photoelectric conversion based on the received light. Specifically, there are phosphors and photoelectric elements that convert phosphor light into voltage signals. The photoelectric element is composed of, for example, a silicon photodiode, a gallium / phosphorus photodiode, or the like.

The light receiving unit 25 includes a lighting detection unit 30 including a calculation unit 26 that performs calculation processing based on the measurement result of the light receiving unit 25 and a display unit 27 that is connected to the calculation unit 26 and displays whether the lamp is turned on or off. It is connected.
Specifically, the calculation unit 26 performs a comparison calculation process on the set reference voltage and the voltage signal from the light receiving unit 25, and outputs a signal indicating lamp lighting or non-lighting to the display unit 27. That is, when the voltage signal is lower than the reference voltage, the calculation unit 26 outputs a signal indicating that the excimer lamp 1 is not lit (hereinafter also referred to as “non-lighting signal”), and the voltage signal is the reference. When the voltage is higher than the voltage, a signal indicating that the excimer lamp 1 is lit (hereinafter also referred to as “lighting signal”) is output.

  The lighting signal or the non-lighting signal output from the arithmetic element 26 is input to the display unit 27. The display unit 27 is configured by a display element such as a liquid crystal, for example, and notifies the user of the lighting state of the excimer lamp 1 according to the lighting signal or the non-lighting signal output from the arithmetic element 26.

A power supply control mechanism 28 that controls the power supplied to the excimer lamp 1 and a transport control mechanism 29 that controls the operation of the transport mechanism 35 are connected to the arithmetic unit 26 based on the non-lighting signal output from the arithmetic unit 26. Yes.
The power supply control mechanism 28 outputs a signal for stopping the supply of the lighting power to the excimer lamp 1 to the power supply device 17 in response to the non-lighting signal from the calculation unit 26. In response to this, the power supply device 17 stops the supply of lighting power to the excimer lamp 1. The transport control mechanism 29 outputs a signal for stopping the transport of the substrate 36 to the transport mechanism 35 in response to the non-lighting signal input from the calculation unit 26. In response to this, the transport mechanism 35 stops the transport of the substrate 36.

An example of the specification of the ultraviolet irradiation device of the present invention is as follows.
When the width of the substrate is 2000 mm, the casing 11 is 600 mm in length, 3000 mm in width, and 300 mm in height.
In the effective light emitting region Z, one end of the light guide unit 202 is arranged at a position where the distance from the end point 42 is about 150 mm.
The discharge vessel 2 is made of synthetic quartz glass, has a total length (including a sealing portion) of 2100 mm, and an outer diameter of 26 mm. The inner electrode 3 is configured by winding a wire made of tungsten having a wire diameter of 0.5 mm, and the length of the coil portion 31 is 2050 mm. The coil part 31 has an outer diameter of 13.5 mm and a pitch of 5 mm. The inner tube 7 is made of synthetic quartz glass and has a total length of 2030 mm, an outer diameter of 16 mm, and an inner diameter of 14 mm. Xenon gas is sealed inside the discharge vessel 2 at a pressure of 20 kPa. The rated power is 800W.

According to the first ultraviolet irradiation device 100 of the present invention as described above, the other of the inner electrode 3 than the one end 321a of the inner electrode 3 connected to the power feeding device 17 in the effective light emitting region Z of the excimer lamp 1. The light guide unit 202 that emits light emitted from the excimer lamp incident from one end, which is provided corresponding to the region X near the end 321b, and the light emitted from the other end of the light guide unit 202 are received. Since the light receiving unit 25 and the lighting detection unit 30 connected to the light receiving unit 25 are provided, any of the effective light emitting regions in the region from the start point 41 to the portion corresponding directly below the light guide unit 202 is selected. Even if the inner electrode 3 is disconnected at a portion, the non-lighting of the excimer lamp can be reliably detected.
Specifically, the light emitted from the excimer lamp is emitted from the other end of the light guide unit 202 to the light receiving unit 25, and the light receiving element 25 outputs a voltage signal corresponding to the light intensity to the arithmetic element 26. Then, a lighting signal or a non-lighting signal is output to the display element 27 by comparing the reference voltage value and the voltage signal by the arithmetic element 26, and the operator turns on the excimer lamp by looking at the display element 27. The state can be confirmed.

  Moreover, according to the first ultraviolet irradiation device 100 of the present invention, the power supply control mechanism 28 that controls the power supply of the lighting power to the excimer lamp 1 and the transport control mechanism 29 that controls the operation of the transport mechanism 35 are provided. Thus, when the inner electrode 3 is disconnected, the supply of lighting power to the excimer lamp 1 can be stopped promptly and the conveyance of the substrate 36 can be stopped. Thereby, unnecessary power supply of the lighting power to the excimer lamp is not continued, and there is no fear that the substrate cleaning process becomes incomplete.

Furthermore, the excimer lamp 1 of the form shown in FIG. 1 has the following advantages.
(1) Since the inner electrode 7 in the discharge space is also covered with the inner tube 7 made of a dielectric material, the discharge between the outer electrode 4 and the outer electrode 4 becomes stable, and a uniform state can be maintained. The occurrence of undesired arc discharge is prevented, excimer light generation efficiency is high, and the inner electrode 3 is not burned out.
(2) Since the inner tube 7 has a structure in which the end thereof is opened in the discharge space, the thermal expansion in the longitudinal direction is freely constrained without any restriction. Compared to the joined structure, the problem of damage or breakage of the discharge vessel is reduced.
(3) The discharge gas in the inner tube 7 circulates in the discharge space through the open end to suppress the temperature rise of the inner electrode 3 and prevent its wear and the temperature of the discharge gas is averaged. Therefore, the temperature rise is suppressed, and the decrease in light output can be prevented.
(4) Since the inner electrode 3 has elasticity, even if the inner electrode 3 is thermally expanded, it absorbs the thermal expansion, thereby sealing the discharge vessel 2 made of quartz glass having a different thermal expansion coefficient. Damage to the discharge vessel 2 can be prevented without affecting the stoppers 22a and 22b.

  The first ultraviolet irradiation device of the present invention is not limited to the embodiment shown in FIG. 1, and various modifications can be made. Hereinafter, another embodiment of the first ultraviolet irradiation device of the present invention will be described with reference to FIGS. 2 to 4 are cross-sectional views of the ultraviolet irradiation device cut along a plane including the tube axis of the excimer lamp, and the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

The ultraviolet irradiation device 200 shown in FIG. 2 is provided with a light guide unit 202 that penetrates the cooling block 20 in an oblique direction, and the light receiving unit 25 is in a state where the light incident surface 251 faces the other end of the light guide unit 202. Except for the point placed on the housing 11, the other configuration is the same as the ultraviolet irradiation device shown in FIG.
The light guide unit 202 is incident from one opening end provided corresponding to the region X closer to the other end 321b of the inner electrode 3 than the one end 321a of the inner electrode 3 in the effective light emitting region Z in the excimer lamp 1. The light emitted from the excimer lamp is emitted from the other opening end provided corresponding to the region Y on the side close to the one end 321a of the inner electrode 3 in the effective light emitting region in the excimer lamp 1.
According to such an ultraviolet irradiation device 200, based on the measurement result obtained by the light receiving unit 25 receiving the light emitted from the other end of the light guide unit 202, the same calculation as the ultraviolet irradiation device shown in FIG. By performing the processing, it is possible to detect the lighting state of the excimer lamp 1 and to control the power supply to the excimer lamp and the conveyance of the substrate.

The ultraviolet irradiation device 300 shown in FIG. 3 does not have a cooling block, is provided with a light guide unit 202 made of a cylindrical light guide, and the light receiving unit 25 has its light incident surface 251 at the other end of the light guide unit 202. 1 is the same as that of the ultraviolet irradiation device shown in FIG. 1 except that it is placed on the housing 11 in a state of facing each other.
The light guide unit 202 is an excimer lamp incident from one end disposed corresponding to a region X closer to the other end 321b of the inner electrode 3 than the one end 321a of the inner electrode 3 in the effective light emitting region Z of the excimer lamp 1. The emitted light is emitted from the other end arranged outside the effective light emitting region in the excimer lamp 1.
According to such an ultraviolet irradiation device 300, based on the measurement result obtained by the light receiving unit 25 receiving the light emitted from the other end of the light guide unit 202, the same calculation as that of the ultraviolet irradiation device shown in FIG. By performing the processing, it is possible to detect the lighting state of the excimer lamp 1 and to control the power supply to the excimer lamp and the conveyance of the substrate. Furthermore, by disposing the light receiving unit 25 outside the effective light emitting region Z, the temperature rise of the light receiving unit can be suppressed, and the light receiving unit 25 can be detected with high accuracy or the life of the light receiving unit is extended.

The ultraviolet irradiation device 400 shown in FIG. 4 is made of, for example, quartz fiber. One end of the ultraviolet irradiation device 400 is inserted into a through hole 45 provided through the cooling block 20 in the vertical direction, and the other end is a light incident surface of the light receiving unit 25. The other configuration is the same as that of the ultraviolet irradiation device shown in FIG. 1 except that the light guide unit 202 connected to 251 and the light receiving unit 25 placed above the housing 11 are provided.
The light guide unit 202 radiates from an excimer lamp incident from one end arranged corresponding to the region X closer to the other end 321b of the inner electrode 3 than the one end 321a of the inner electrode 3 in the effective light emitting region of the excimer lamp 1. The emitted light is emitted from the other end.
According to such an ultraviolet irradiation device 400, the same light as that of the ultraviolet irradiation device shown in FIG. 1 is obtained based on the measurement result obtained by the light receiving unit 25 receiving the light emitted from the other end of the light guide unit 202. By performing the arithmetic processing, it is possible to detect the lighting state of the excimer lamp 1 and to control the power supply to the excimer lamp and the conveyance of the substrate. Furthermore, by disposing the light receiving unit 25 outside the effective light emitting region Z, the temperature rise of the light receiving unit can be suppressed, and the light receiving unit 25 can be detected with high accuracy or the life of the light receiving unit is extended.

[Second Embodiment]
FIG. 5 shows a cross-sectional view of the second ultraviolet irradiation apparatus of the present invention cut along a plane including the tube axis of the excimer lamp. The same reference numerals as those in FIG. 1 denote the same or corresponding parts. The ultraviolet irradiating device 500 is the same as the ultraviolet irradiating device shown in FIG. 1 except that the excimer lamp 50 having a double tube structure is used.
The excimer lamp 50 includes a cylindrical outer tube 51 made of a dielectric material such as quartz glass, and a cylindrical inner tube 52 made of a dielectric material such as quartz glass and having an outer diameter smaller than the inner diameter of the outer tube 51. And a discharge vessel 55 having a double-tube structure comprising side wall portions 53 and 54 hermetically closing both ends of a cylindrical space formed by the outer tube 51 and the inner tube 52. A cylindrical discharge space S formed by the above is filled with, for example, xenon gas as a discharge gas.
The outer tube 51 forming the discharge vessel 55 is in close contact with an outer electrode 56 made of an aluminum film formed by, for example, vapor deposition or screen printing so as to have a mesh-like opening on the outer peripheral surface thereof. A plate-like inner electrode 57 made of, for example, aluminum is provided in close contact with the inner peripheral surface, and the power feeding device 17 is connected to the outer electrode 56 and the inner electrode 57.

According to the second ultraviolet irradiation device of the present invention, in the effective light emission region Z of the excimer lamp 50, the region closer to the other end 561b of the outer electrode 56 than the one end 561a of the outer electrode 56 connected to the power feeding device 17. A light guide unit 202 that is provided corresponding to X and emits light emitted from an excimer lamp incident from one end from the other end; and a light receiving unit 25 that receives light emitted from the other end of the light guide unit 202; By including the lighting detection means 30 connected to the light receiving unit 25, for example, due to the difference in thermal expansion coefficient between the outer electrode 56 and the outer tube 51, the effective light emitting region Z in the excimer lamp 1 is Even if a part of the outer electrode 56 is peeled off at any part of the region from the starting point 41 to the portion corresponding to the position immediately below the light guide unit 202, the non-lighting of the excimer lamp 50 can be reliably detected. Can. In particular, since the current density on the power supply side increases, the temperature tends to rise, so there is a high probability of fusing and peeling, so that the non-lighting of the excimer lamp can be reliably detected by adopting the configuration of the present invention. Can do.
In addition, since the power supply control mechanism 28 that controls the power supply of the lighting power to the excimer lamp 50 and the transport control mechanism 29 that controls the operation of the transport mechanism 35 are provided, when a part of the outer electrode 56 is peeled off, In addition, the supply of lighting power to the excimer lamp 1 can be stopped and the conveyance of the substrate 36 can be stopped. Thereby, unnecessary power supply of the lighting power to the excimer lamp is not continued, and there is no fear that the cleaning process of the substrate 36 becomes incomplete.

[Third Embodiment]
FIG. 6 shows a cross-sectional view of the third ultraviolet irradiation apparatus of the present invention cut along a plane including the tube axis of the excimer lamp. The same reference numerals as those in FIG. 1 denote the same or corresponding parts.
In the ultraviolet irradiation device 600, both the external leads 6 a and 6 b and the outer electrode 4 are connected to the power supply device 17 by a power supply line 18. A light guide portion 202 that penetrates the cooling block 20 in the vertical direction is formed corresponding to a region in the effective light emitting region Z in the vicinity of the central portion (a region indicated by a V line in FIG. 7 described later). The light receiving unit 25 is placed on the housing 11 with the light incident surface 251 facing the end. The “region near the center” is a position where the light receiving unit 25 can observe the center of the excimer lamp. Except for these points, the configuration is the same as that of the ultraviolet irradiation device shown in FIG.

The effects of the third ultraviolet irradiation device of the present invention will be described below.
When the inner electrode 3 is cut only at one location, there is no particular problem because the both ends of the inner electrode are electrically connected to the power supply device, so that the lighting continues on both sides of the disconnected location. However, as shown in FIG. 7, when the inner electrode 3 is cut at two points (disconnection points 44 and 45 in FIG. 7), the region indicated by the U line connecting the start point 41 and the disconnection point 44 and the disconnection point 45 Although the lighting continues in the area indicated by the W line connecting the end point 42, the area indicated by the V line connecting the disconnection point 44 and the disconnection point 45 is not lighted by being electrically disconnected from the power feeding device. When the disconnection point 44 is disconnected first, the length of the inner electrode becomes U <V + W, the current value flowing through the power supply unit on the b side is larger than the power supply unit on the a side, and the next disconnection is b from the central portion. Disconnect at the disconnection point 45 on the side. According to the third ultraviolet irradiation device, even when the inner electrode 3 is disconnected at two places as described above, the light guide unit 202 corresponds to the region indicated by the V line near the center of the effective light emitting region Z. Therefore, the non-lighting of the excimer lamp can be reliably detected by the voltage signal based on the light received by the light receiving unit 25 via the light guide unit 202.

  In addition, the excimer lamp 1 is provided promptly when the inner electrode 3 is disconnected by providing a power supply control mechanism for controlling the power supply of the lighting power to the excimer lamp 1 and a transport control mechanism for controlling the operation of the transport mechanism. It is possible to stop the feeding of the lighting power to the substrate and stop the conveyance of the substrate. Thereby, unnecessary power supply of the lighting power to the excimer lamp is not continued, and there is no fear that the substrate cleaning process becomes incomplete.

The first to third ultraviolet irradiation devices as described above have a structure in which a window member is fitted into the opening of the housing. However, the present invention is not limited to this, and a structure without using a window member can also be adopted.
The first to third ultraviolet irradiation devices have a structure having a cooling block in the housing. However, the present invention is not limited to this, and a structure having no cooling block can be adopted. The formed through hole functions as a light guide.
Further, in the above embodiment, an excimer lamp having a structure in which the outer periphery of the inner electrode is covered with an inner tube made of a dielectric material has been described. However, the present invention is not necessarily limited to this, and a single cylindrical structure without an inner tube. It is also possible to construct an ultraviolet irradiation device using an excimer lamp.

In addition, as in a conventional ultraviolet irradiation device, a vacuum ultraviolet light emitted from the excimer lamp is converted into visible light by a phosphor layer provided on the outer surface of the excimer lamp, and a voltage signal corresponding to the intensity of the visible light is converted. Based on the above, it is also possible to detect the lighting state of the excimer lamp. Alternatively, the light receiving unit that detects the light from the lamp may be a light receiving element that can directly detect vacuum ultraviolet light without using a phosphor. Also, a xenon excimer lamp can detect ultraviolet light, visible light, and infrared light emitted from the lamp.
Of course, in excimer lamps that emit 222 nm light mixed with krypton and chlorine that emit light other than vacuum ultraviolet light, excimer lamps that emit 308 nm light mixed with xenon and chlorine, etc. Can be reliably detected.

Sectional drawing of the 1st ultraviolet irradiation device of this invention is shown. Sectional drawing of the other form which concerns on the 1st ultraviolet irradiation device of this invention is shown. Sectional drawing of the other form which concerns on the 1st ultraviolet irradiation device of this invention is shown. Sectional drawing of the other form which concerns on the 1st ultraviolet irradiation device of this invention is shown. Sectional drawing of the 2nd ultraviolet irradiation device of this invention is shown. Sectional drawing of the 3rd ultraviolet irradiation device of this invention is shown. Sectional drawing for demonstrating the effect of the 3rd ultraviolet irradiation device of this invention is shown. Sectional drawing of the conventional ultraviolet irradiation device is shown. Sectional drawing containing the tube axis | shaft of the excimer lamp of the conventional single cylinder type structure is shown. It is sectional drawing for demonstrating the problem in the conventional ultraviolet irradiation device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Excimer lamp 2 Discharge vessel 3 Inner electrode 4 Outer electrode 5 Metal foil 6 External lead 7 Inner tube 8 Support member 11 Housing 12 Opening 13 Window member 14 Through hole 15 Inlet hole 16 Outlet hole 17 Feeder device 18 Feeder line 20 Cooling block 21 Straight tube portion 22 Sealing portion 25 Light receiving portion 26 Calculation portion 27 Display portion 28 Power supply control mechanism 29 Transfer control mechanism 31 Coil portion 32 Straight line portion 35 Transfer mechanism 36 Substrate 50 Excimer lamp 51 Outer tube 52 Inner tube 53 Side wall portion 54 Side wall Part 55 discharge vessel 56 outer electrode 57 inner electrode 100 ultraviolet irradiation device 201 groove part 202 light guide part

Claims (2)

A discharge vessel made of a dielectric material and filled with a discharge gas in its internal discharge space, and a pair of inner sides arranged in the discharge vessel facing each other with the dielectric material constituting the discharge vessel interposed An excimer lamp having an electrode and an outer electrode disposed outside the discharge vessel ;
A power feeding device that is electrically connected to each of the pair of electrodes and feeds power to the excimer lamp, a light guide unit disposed in an effective light emission region of the excimer lamp, and a light receiving unit that receives light emitted from the light guide unit A lighting detection means for detecting a lighting state of the excimer lamp based on a measurement result of the light receiving unit,
An ultraviolet irradiation device comprising:
The inner electrode is connected to the power feeding device at one end;
The ultraviolet light irradiation device, wherein the light guide portion is disposed corresponding to a region near the other end of the inner electrode. A discharge vessel made of a dielectric material, in which a discharge gas is filled in a discharge space therein, and a pair of electrodes arranged outside the discharge vessel facing each other with the dielectric material constituting the discharge vessel interposed An excimer lamp having
A power supply device that is electrically connected to each of the pair of electrodes and supplies power to the excimer lamp, a light guide unit disposed in an effective light emission region of the excimer lamp, and a light receiving unit that receives light emitted from the light guide unit A lighting detection means for detecting a lighting state of the excimer lamp based on a measurement result of the light receiving unit,
An ultraviolet irradiation device comprising:
The pair of electrodes are both connected to the power feeding device at one end,
The ultraviolet light irradiating device, wherein the light guide portion is disposed corresponding to a region near the other end of the pair of electrodes.

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