JP2005197082A - Jet nozzle and light source device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jet nozzle capable of stably supplying a target matter in a laser beam irradiation area of a EUV light source by restraining clogging up of the nozzle with a foreign substance through prevention of its infiltration into a flow channel at a tip part of the nozzle and stabilizing spraying direction of the target matter. <P>SOLUTION: The jet nozzle is for spraying the target matter to be a target on which a laser beam is irradiated for generating extreme ultraviolet rays and is provided with a piping part 30 for supplying liquid or gas target matter, a flange part integrated with the piping part on a first face, and a nozzle tip part 10 spraying from a discharging port through the flow channel the target matter supplied from the piping part into an inflow port. By the inflow port set at a position protruded farther from the first face of the flange part, a protruded part with a flow channel is formed at the tip of the nozzle tip part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is a jet nozzle used in a light source device that generates extreme ultra violet (EUV) light, and is used for injecting a target material that is irradiated with a laser beam to generate EUV light. It relates to a jet nozzle. Furthermore, the present invention relates to a light source device using such a jet nozzle.

  With the miniaturization of semiconductor processes, the miniaturization of optical lithography is rapidly progressing, and in the next generation, fine processing of 100 to 70 nm and further fine processing of 50 nm or less are required. For example, in order to meet the demand for fine processing of 50 nm or less, development of an exposure apparatus that combines an EUV light source with a wavelength of about 13 nm and a reduced projection reflection optical system (cataoptric system) is expected.

  As the EUV light source, an LPP (laser produced plasma) light source using plasma generated by irradiating a target with a laser beam, a DPP (discharge produced plasma) light source using plasma generated by discharge, and orbital radiation light There are three types of SR (synchrotron radiation) light sources used. Among these, since the LPP light source can considerably increase the plasma density, extremely high brightness close to that of black body radiation can be obtained, and light emission only in a necessary wavelength band is possible by selecting a target material, which is almost isotropic. Because it is a point light source with a typical angular distribution, there is no structure such as an electrode around the light source, and it is possible to secure a very large collection solid angle of 2πsterad. It is considered to be a powerful light source for required EUV lithography.

  FIG. 11 shows a configuration of a conventional light source device. The nozzle 101 injects a target substance (hereinafter referred to as “target substance”) supplied from the target supply apparatus 102 downward. Plasma 105 is generated by irradiating the target with a laser beam formed by converging the laser beam generated from the driving laser 103 by the condenser lens 104. The EUV light emitted from the plasma 105 is condensed by the condensing mirror 106 and is transmitted as a light beam (for example, parallel light) 107 to the exposure machine.

  A jet nozzle for target injection used for an EUV light source such as the nozzle 101 generally has a flow path from the top to the bottom in order to stably supply a liquid or gaseous target material to the laser beam irradiation region. It is desirable to form.

  FIG. 12 is a cross-sectional view of a conventional jet nozzle. As shown in FIG. 12, a conventional nozzle 101 has a nozzle tip portion 110 and a piping portion 112, and is supported by a holder 113. The target material is supplied from the target supply device 102 shown in FIG. 11 to the piping unit 112 and is sent from the inlet of the nozzle tip 110 to the flow path formed in the nozzle tip 110. Injected from the discharge port. Here, the inner diameter of the flow path of the nozzle tip portion 110 is smaller than the inner diameter of the piping portion 112.

  Next, a case where a foreign substance is mixed in the target material will be described. FIG. 13 is a diagram for explaining a case where a foreign substance is mixed in the target material. As shown in FIG. 13, the foreign material flowing together with the target material is likely to gather near the inlet of the nozzle tip 110, and when the foreign material enters the flow path of the nozzle tip 110, clogging occurs. There is a problem that the injection direction of the target material becomes unstable. Furthermore, there is a problem that the target material cannot be ejected when a plurality of foreign matters or foreign matters larger than the inner diameter of the nozzle tip portion 110 block the inlet of the nozzle tip portion 110.

  In particular, the flow path of the nozzle tip 110 has a very small inner diameter of several μm to several hundreds of μm, so foreign matter of several μm to several tens of μm can cause clogging in the nozzle tip 110 and cause the target material to be clogged. There is a possibility that the injection direction becomes unstable or the target material cannot be injected. Note that the same problem occurs because the foreign matter may settle and block the inflow port even during the operation standby without injecting the target material.

  As a related technique, the following Patent Document 1 discloses a nozzle that is used together with an ultra-ultraviolet light source to generate a larger gas cluster distribution and increase the efficiency of the ultra-ultraviolet light. In this nozzle, three annular portions are formed as first to third portions, and in the first portion, the supplied gas that forms many clusters of fine atomic dimensions is expanded. Can reduce the gas temperature and the clusters formed. In the second part, the number of clusters emerging from the first part can be reduced by compressing the gas. In the third part, the size of the cluster coming out of the second part can be increased. However, this Patent Document 1 does not describe foreign matters mixed in a target gas.

Patent Document 2 below discloses a laser plasma extreme ultraviolet light source that generates larger droplets for a plasma target material. According to the nozzle of this laser plasma extreme ultraviolet light source, due to the pressure and flow rate of the liquid passing through the narrow throat and the shape of the nozzle, the liquid is instantaneously dispersed as it travels through the extended part of the nozzle. High density droplet spray can be formed. However, this Patent Document 2 does not describe the foreign matters mixed in the target liquid.
Japanese Patent Laid-Open No. 2001-313198 (pages 1, 3 and 2) JP 2002-174700 A (pages 1 and 3, FIG. 3)

  Therefore, in view of the above points, the present invention suppresses the clogging of the nozzle by the foreign matter by preventing the foreign matter from entering the flow path at the nozzle tip, stabilizes the injection direction of the target material, An object of the present invention is to provide a jet nozzle capable of stably supplying a substance to a laser beam irradiation region of an EUV light source. Another object of the present invention is to provide a light source device using such a jet nozzle.

  In order to solve the above-described problems, a jet nozzle according to the present invention is a jet nozzle that is used in a light source device and that jets a target material that is a target irradiated with a laser beam to generate extreme ultraviolet light, and is a liquid Alternatively, it has a pipe part for supplying a gaseous target material and a flange part integrated with the pipe part on the first surface, and discharges the target material supplied from the pipe part to the inlet through the flow path. A nozzle tip portion that injects from the outlet, and the inflow port is provided at a position protruding from the first surface of the flange portion, whereby a protrusion portion having a flow path is formed at the nozzle tip portion. .

  Here, the outer diameter of the protruding portion may be reduced as it protrudes from the first surface of the flange portion. Alternatively, in order to prevent the solid mixed in the target material from moving from the region between the projecting portion and the piping portion into the flow path of the projecting portion, the outer diameter of the projecting portion is the first of the flange portion. You may make it increase in the position of predetermined distance from a surface rather than the position in less than predetermined distance. In this case, the outer diameter of the protruding portion may be reduced as it protrudes from the first surface of the flange portion at a position equal to or greater than a predetermined distance from the first surface of the flange portion.

  In the above, in order to prevent the solid mixed in the target material from moving from the region between the protruding portion and the piping portion into the flow path of the protruding portion, the inner diameter of the piping portion is the flange portion of the nozzle tip portion. In the position of a predetermined distance from the first surface, the distance may be smaller than that at a position less than the predetermined distance. Moreover, you may make it form a discharge port in the position which does not protrude rather than the 2nd surface which opposes the 1st surface of a flange part. Furthermore, the flow path may be formed in a tapered shape by reducing the inner diameter of the flow path as it goes from the inlet to the outlet in at least a part of the nozzle tip.

  A light source device according to the present invention is a light source device that generates extreme ultraviolet light by irradiating a target with a laser beam, the target supplying a liquid or gaseous target material to any one of the jet nozzles and a pipe section. A supply unit, a laser unit that generates a plasma by irradiating a target material ejected from a nozzle tip, and a condensing optical system that collects and emits extreme ultraviolet light emitted from the plasma. It has.

  According to the present invention, in the jet nozzle, the inlet is provided at a position protruding from the first surface of the flange portion, and the protruding portion having the flow path is formed at the nozzle tip portion. Intrusion of foreign matter into the road can be prevented, and clogging due to foreign matter can be suppressed. As a result, it becomes possible to stabilize the jet direction of the target material and stably supply the target material to the laser beam irradiation region. Further, by using such a jet nozzle, it is possible to provide a light source device with a short down time by reducing the number of times of maintenance due to clogging due to foreign matters.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. The same constituent elements are denoted by the same reference numerals, and the description thereof is omitted.
FIG. 1 is a cross-sectional view of a jet nozzle according to a first embodiment of the present invention. As shown in FIG. 1, a nozzle tip portion 10 and a piping portion 30 are formed in this jet nozzle, and are supported by a holder 40. In the present application, the flat plate portion of the nozzle tip portion 10 supported by the holder 40 is referred to as a “flange portion”.

  The target material is supplied from the target supply device to the piping unit 30 and is supplied from the inlet of the nozzle tip 10 to the flow path formed in the nozzle tip 10 and injected from the discharge port. Is done. Here, the inner diameter of the flow path of the nozzle tip portion 10 is smaller than the inner diameter of the piping portion 30.

  The target material is used to cool chips generated when each part of the jet nozzle is manufactured, metals and oxides peeled off from the target supply device by repeated temperature control with a large temperature difference, and the target material. The accompanying solidified material or the like is mixed as a solid foreign substance.

  The nozzle tip portion 10 of the jet nozzle according to the present embodiment has an inflow port protruding upstream from the first surface (upper surface) 10A of the flange portion, and the protruding portion having a flow path is formed in the nozzle tip portion 10. Is formed. Note that the inner diameter of the flow path is constant from the inlet to the outlet. Accordingly, the inlet is provided above the lowermost part of the pipe part 30, that is, upstream of the upper surface 10 </ b> A of the flange part in the flow path of the target material, and between the protruding part of the nozzle tip part 10 and the pipe part 30. Since a groove is formed in this area, foreign matter is likely to accumulate in the groove, and foreign matter is difficult to gather around the inlet.

  By making the nozzle tip 10 in such a shape, it is possible to prevent foreign matter from entering the flow path of the nozzle tip 10. As a result, nozzle clogging due to foreign matter can be suppressed, the target material injection direction can be stabilized, and the target material can be stably supplied to the laser beam irradiation region. Note that the target material can be more stably supplied to the laser beam irradiation region by further increasing the protrusion amount of the protrusion.

  Further, in the jet nozzle according to the present embodiment, maintenance of the nozzle and the like can be performed, but it is caused by clogging by foreign matter by preventing foreign matter from entering the flow path of the nozzle tip 10. The number of maintenance can be reduced, and a device with short downtime can be provided.

Next, a second embodiment of the present invention will be described.
FIG. 2 is a cross-sectional view of a jet nozzle according to the second embodiment of the present invention. As shown in FIG. 2, the nozzle tip portion 11 of the jet nozzle according to the present embodiment has an inflow port protruding upstream from the first surface (upper surface) 11A of the flange portion, and has a flow path. The part is formed at the nozzle tip 11. Furthermore, the protrusion is formed in a knife edge shape toward the upstream side. That is, the outer diameter of the protruding portion decreases as it protrudes from the upper surface 11A of the flange portion. About another structure and shape, it is the same as that of the jet nozzle shown in FIG.

  Accordingly, the inflow port is provided above the lowermost part of the pipe part 30 and a groove is formed in a region between the protruding part of the nozzle tip 11 and the pipe part 30, so that foreign matter accumulates in the groove. In addition, since the protruding portion has a knife edge shape toward the upstream side, it is further difficult for foreign matter to collect around the inlet.

  By making the nozzle tip 11 in such a shape, it is possible to further prevent foreign matter from entering the flow path of the nozzle tip 11. As a result, nozzle clogging due to foreign matter can be suppressed, the target material injection direction can be stabilized, and the target material can be stably supplied to the laser beam irradiation region.

Next, a third embodiment of the present invention will be described.
FIG. 3 is a cross-sectional view of a jet nozzle according to the third embodiment of the present invention. As shown in FIG. 3, the nozzle tip portion 12 of the jet nozzle according to the present embodiment has an inflow port protruding upstream from the first surface (upper surface) 12A of the flange portion, and has a flow path. The part is formed at the nozzle tip 12. Further, the burrs are formed by making the outer diameter of the upper part of the protruding part larger than the outer diameter of the lower part. That is, the outer diameter of the protrusion is increased at a predetermined distance from the upper surface 12A of the flange portion than at a position less than the predetermined distance. About another structure and shape, it is the same as that of the jet nozzle shown in FIG.

  Therefore, the inflow port is provided above the lowermost part of the pipe part 30 and a groove is formed in the region between the protruding part of the nozzle tip 12 and the pipe part 30, so that foreign matter accumulates in the groove. It is easy, and since the burrs are formed by making the outer diameter of the upper part of the protruding part larger than the outer diameter of the lower part, it prevents the foreign matter that has once settled from floating again and gathering around the inlet. .

  By making the nozzle tip 12 in such a shape, it is possible to further prevent foreign matter from entering the flow path of the nozzle tip 12. As a result, nozzle clogging due to foreign matter can be suppressed, the target material injection direction can be stabilized, and the target material can be stably supplied to the laser beam irradiation region.

Next, a fourth embodiment of the present invention will be described.
FIG. 4 is a cross-sectional view of a jet nozzle according to the fourth embodiment of the present invention. As shown in FIG. 4, the nozzle tip portion 13 of the jet nozzle according to the present embodiment has an inflow port protruding upstream from the first surface (upper surface) 13 </ b> A of the flange portion, and has a flow path. The part is formed at the nozzle tip 13. Further, the burrs are formed by making the outer diameter once larger than the outer diameter of the lower part at the upper part of the projecting part, and the burrs are formed in a knife edge shape toward the upstream. That is, the outer diameter of the protrusion increases at a predetermined distance from the upper surface 13A of the flange than at a position less than the predetermined distance, and protrudes at a position greater than or equal to the predetermined distance from the upper surface 13A of the flange. The outer diameter of the portion becomes smaller as it protrudes from the upper surface 13A of the flange portion. About another structure and shape, it is the same as that of the jet nozzle shown in FIG.

  Therefore, the inflow port is provided above the lowermost part of the pipe part 30 and a groove is formed in a region between the protruding part of the nozzle tip part 13 and the pipe part 30, so that foreign matter accumulates in the groove. In addition, since the burrs are formed, the foreign matter that has once settled is prevented from floating again and collecting around the inlet. Furthermore, since the burrs are formed in a knife edge shape toward the upstream side, it is further difficult for foreign matter to collect around the inlet.

  By making the nozzle tip 13 in such a shape, it is possible to further prevent foreign matter from entering the flow path of the nozzle tip 13. As a result, nozzle clogging due to foreign matter can be suppressed, the target material injection direction can be stabilized, and the target material can be stably supplied to the laser beam irradiation region.

Next, a fifth embodiment of the present invention will be described.
FIG. 5 is a cross-sectional view of a jet nozzle according to the fifth embodiment of the present invention. As shown in FIG. 5, in the pipe portion 31 of the jet nozzle according to the present embodiment, a burrs are formed by reducing the inner diameter at the upstream position that is the same as the uppermost portion of the protruding portion of the nozzle tip 10. Has been. That is, the inner diameter of the pipe portion 31 is smaller at a predetermined distance from the upper surface 10A of the nozzle tip 10 than at a position less than the predetermined distance. About another structure and shape, it is the same as that of the jet nozzle shown in FIG.

  Accordingly, the inflow port is provided above the lowermost part of the pipe part 31 and a groove is formed in a region between the protruding part of the nozzle tip 10 and the pipe part 31. Therefore, foreign matter accumulates in the groove. It is easy, and since the burrs are formed by reducing the inner diameter of the pipe portion 31 at the upstream position that is about the same as the uppermost portion of the protruding portion of the nozzle tip portion 10, the foreign matter that has once settled rises again. To prevent it from gathering around the inlet.

  By making the piping part 31 into such a shape, it is possible to prevent foreign matters that have once settled from rising again and collecting around the inlet. As a result, nozzle clogging due to foreign matter can be suppressed, the target material injection direction can be stabilized, and the target material can be stably supplied to the laser beam irradiation region. In this embodiment, the shape of the nozzle tip is the same as the shape of the nozzle tip in the first embodiment, but is the same as the shape of the nozzle tip in the second to fourth embodiments. It is good also as a shape.

Next, a sixth embodiment of the present invention will be described.
FIG. 6 is a cross-sectional view of a jet nozzle according to the sixth embodiment of the present invention. As shown in FIG. 6, the nozzle tip portion 14 of the jet nozzle according to the present embodiment has an inflow port protruding upstream from the first surface (upper surface) 14 </ b> A of the flange portion, and has a flow path. The part is formed at the nozzle tip 14. On the other hand, the discharge port does not protrude further downstream than the second surface (lower surface) 14B of the flange portion. About another structure and shape, it is the same as that of the jet nozzle shown in FIG.

  Therefore, the inflow port is provided above the lowermost part of the pipe part 30 and a groove is formed in the region between the protruding part of the nozzle tip 14 and the pipe part 30, so that foreign matter accumulates in the groove. It is easy and it is difficult for foreign matter to gather around the inlet. Moreover, since the discharge port does not protrude downstream from the lower surface 14B of the flange portion, the flow path length of the nozzle tip can be shortened, thereby reducing the pressure loss of the target material in the flow path of the nozzle tip. By doing so, the fall of the jet flow velocity of the target material injected from a protrusion part can be suppressed.

  FIG. 7 is a diagram showing the pressure distribution of the target material when the jet nozzle shown in FIG. 6 is used. In FIG. 7, the pressure of the target material when the jet nozzle according to the present embodiment is used is shown by a solid line, and for comparison, the pressure of the target material when the jet nozzle according to the first embodiment is used. It is indicated by a broken line. Note that the inner diameter of the flow path of the nozzle tip 14 of the jet nozzle according to the present embodiment is equal to the inner diameter of the flow path of the nozzle tip 10 of the jet nozzle according to the first embodiment. Further, the roughness of the inner surface of the flow path of the nozzle tip portion 14 is equal to the roughness of the inner surface of the flow path of the nozzle tip portion 10 of the jet nozzle according to the first embodiment.

  As shown in FIG. 7, the target material flowing in the piping part 30 has a constant pressure, but at the inlet of the nozzle tip part 10 or 14 whose inner diameter is smaller than that of the piping part 30, Pressure loss occurs due to the generation of vortices. Furthermore, in the flow path of the nozzle tip 10 or 14, the target material moves downstream, and pressure loss occurs due to friction between the target material and the wall surface. Since the flow path length of the nozzle tip portion 14 of the jet nozzle according to this embodiment is shorter than the flow path length of the nozzle tip portion 10 of the jet nozzle according to the first embodiment, in this embodiment, the nozzle tip portion Since the pressure loss of the target material in the flow path of the target material can be made smaller than in the first embodiment, the pressure contributing to the injection of the target material can be made larger than in the first embodiment, It is possible to suppress a decrease in the jet flow rate of the target material injected from the outlet.

  By forming the nozzle tip portion 14 in such a shape, it is possible to prevent foreign matter from entering the flow path of the nozzle tip portion 14 without causing a decrease in the jet flow velocity due to the provision of the protruding portion. . As a result, nozzle clogging due to foreign matter can be suppressed, the target material injection direction can be stabilized, and the target material can be stably supplied to the laser beam irradiation region. In the present embodiment, the shape on the upstream side of the nozzle tip is described as being the same as the shape in the first embodiment, but may be the same as the shape in the second to fourth embodiments. Similarly to the embodiment, burrs may be formed in the piping portion.

Next, a seventh embodiment of the present invention will be described.
FIG. 8 is a cross-sectional view of a jet nozzle according to the seventh embodiment of the present invention. As shown in FIG. 8, the nozzle tip 15 of the jet nozzle according to the present embodiment has an inflow port protruding upstream from the first surface (upper surface) 15A of the flange portion, and has a flow path. The part is formed at the nozzle tip 15. Furthermore, in at least a part of the nozzle tip portion 15, a taper is formed by reducing the inner diameter of the flow path from the inlet to the outlet. Other configurations and shapes are the same as those shown in FIG.

  FIG. 9 is a diagram showing the pressure distribution of the target material when the jet nozzle shown in FIG. 8 is used. In FIG. 9, the pressure of the target material when the jet nozzle according to the present embodiment is used is indicated by a solid line, and for comparison, the pressure of the target material when the jet nozzle according to the first embodiment is used. It is indicated by a broken line. Note that the inner diameter of the discharge port of the nozzle tip portion 15 of the jet nozzle according to the present embodiment is equal to the inner diameter of the discharge port of the nozzle tip portion 10 of the jet nozzle according to the first embodiment. Further, the roughness of the inner surface of the flow path of the nozzle tip 15 and the roughness of the inner surface of the flow path of the nozzle tip 10 of the jet nozzle according to the first embodiment are equal.

  As shown in FIG. 9, the target material flowing in the pipe portion 30 has a constant pressure, but at the inlet of the nozzle tip portion 10 or 15, the inner diameter is suddenly smaller than that of the pipe portion 30. Pressure loss is caused by the vortex of the material. Further, in the flow path of the nozzle tip 10 or 15, the target material moves downstream, and pressure loss occurs due to friction between the target material and the wall surface. By providing a taper in the flow path on the inlet side of the nozzle tip 15 of the jet nozzle according to the present embodiment, it is difficult for the vortex of the target material to occur at the inlet, so in this embodiment, the nozzle tip Since the pressure loss of the target material at the inlet of the part can be made smaller than the pressure loss in the first embodiment, the pressure contributing to the injection of the target material can be made larger than the pressure in the first embodiment. It is possible to suppress a decrease in the jet flow velocity of the target material ejected from the discharge port. However, if the inner diameter of the inlet is increased in order to provide a taper in the flow path on the inlet side, the probability that foreign matter will enter the flow path at the nozzle tip increases, so the probability that foreign matter will enter will be greater than that of the prior art. It is necessary to provide a taper within a range that becomes smaller.

  By making the nozzle tip 15 in such a shape, it is possible to prevent foreign matter from entering the flow path of the nozzle tip 15 without causing a decrease in the jet flow velocity due to the provision of the protrusion. . As a result, nozzle clogging due to foreign matter can be suppressed, the target material injection direction can be stabilized, and the target material can be stably supplied to the laser beam irradiation region. In the present embodiment, the outer shape of the nozzle tip is described as being the same as the outer shape in the first embodiment, but may be the same as the outer shape in the second to fourth embodiments, or the fifth embodiment. Similarly, a burr may be formed in the piping portion. Further, similarly to the sixth embodiment, the discharge port may not be protruded downstream from the lower surface of the flange portion.

  Next, a light source device according to an embodiment of the present invention will be described. FIG. 10 shows a configuration of a light source device according to an embodiment of the present invention. The light source device can stably supply the target material to the laser beam irradiation region by suppressing the clogging of the nozzle due to foreign matter by ejecting the target material using the jet nozzle described above.

  As shown in FIG. 10, the light source device includes a driving laser 51 that generates a laser beam and an irradiation optical system that condenses the laser beam generated by the driving laser 51 as a laser unit. In the present embodiment, the irradiation optical system is configured by a condenser lens 52. As the condenser lens 52, a plano-convex lens or a cylindrical lens is used.

  Further, the light source device serves as a target supply unit, a target supply device 53 that supplies a target material that is irradiated with a laser beam, a jet nozzle 54 that injects a target material supplied from the target supply device 53, And a condensing optical system that condenses and emits EUV light emitted from the plasma.

  In the present embodiment, the jet nozzle 54 includes the nozzle tip portion 10, the piping portion 30, and the holder 40. Further, the condensing optical system is constituted by a condensing mirror 55. As the condensing mirror 55, a parabolic mirror, a spherical mirror, a spheroid concave mirror, or a spherical mirror having a plurality of curvatures can be used.

  In the present embodiment, EUV light has a wavelength of 5 nm to 50 nm. The laser unit generates plasma by irradiating the target supplied from the target supply unit with a laser beam, and the condensing mirror 55 collects and emits EUV light emitted from the plasma.

  The target can be used in the form of either a gas jet or a liquid jet. In the case of a gas jet, a substance that is in a gaseous state at room temperature (20 ° C.) corresponds to, for example, xenon (Xe), a mixture containing xenon as a main component, argon (Ar), or krypton (Kr). it can. In the case of a liquid jet, water obtained by liquefying the gas by cooling under pressure, or water or alcohol in a liquid state at room temperature can be used.

  When the target substance is in a gas state from the beginning, the gas may be supplied in a gas state by applying pressure to the gas and releasing it from the discharge port of the jet nozzle 54. Alternatively, this gas may be supplied as a jet (jet) of an aggregate (cluster ion) of charged atoms or molecules formed by aggregation of a plurality of atoms or molecules with positive ions or negative ions as nuclei. .

  In this embodiment, liquid xenon (Xe) is used as the target material. In that case, the generated EUV light has a wavelength of about 10 nm to about 15 nm. The target supply device 53 pressurizes and cools liquid xenon, thereby jetting liquid xenon downward from the discharge port of the jet nozzle 54. Therefore, the ejected liquid xenon flows vertically according to the opening shape of the discharge port, and forms a liquid xenon column (continuous flow) or droplet.

  The laser beam generated from the driving laser 51 is condensed by the condensing lens 52, becomes a laser beam having a substantially line-shaped cross section, passes through the hole formed in the condensing mirror 55. Irradiation toward liquid xenon pillars or droplets. Plasma 56 is generated at a position where the irradiated laser beam intersects the liquid xenon column or droplet.

  The EUV light emitted from the plasma 56 is condensed by a condensing mirror 55 constituting a condensing optical system, becomes a light beam (for example, parallel light) 57, and is supplied to an exposure machine. It is desirable that the optical axis of the condensing optical system intersects with the approximate center of the plasma 56. As mirror coating of the inner surface (condenser mirror) of the condenser mirror 55, Mo / Si or Mo / Sr is used when generating EUV light with a wavelength of 13 nm, and Mo when generating EUV light with a wavelength of 11 nm. When / Be or Mo / Sr is used, the light collection efficiency can be improved.

  The present invention can be used for a jet nozzle for injecting a target substance in a light source device that generates EUV light. Furthermore, the present invention can also be used in a light source device using such a jet nozzle.

It is sectional drawing of the jet nozzle which concerns on the 1st Embodiment of this invention. It is sectional drawing of the jet nozzle which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the jet nozzle which concerns on the 3rd Embodiment of this invention. It is sectional drawing of the jet nozzle which concerns on the 4th Embodiment of this invention. It is sectional drawing of the jet nozzle which concerns on the 5th Embodiment of this invention. It is sectional drawing of the jet nozzle which concerns on the 6th Embodiment of this invention. It is a figure which shows the pressure distribution of the target material at the time of using the jet nozzle shown in FIG. It is sectional drawing of the jet nozzle which concerns on the 7th Embodiment of this invention. It is a figure which shows the pressure distribution of the target material at the time of using the jet nozzle shown in FIG. It is a figure which shows the structure of the light source device which concerns on one Embodiment of this invention. It is a figure which shows the structure of the conventional light source device. It is sectional drawing of the conventional jet nozzle. It is a figure for demonstrating the case where the foreign material is mixed in the target material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10-15 ... Nozzle tip part, 30, 31 ... Pipe part, 40 ... Holder, 51 ... Driving laser, 52 ... Condensing lens, 53 ... Target supply apparatus, 54 ... Jet nozzle, 55 ... Condensing mirror, 56 ... Plasma, 57 ... luminous flux

Claims (8)

A jet nozzle that is used in a light source device and injects a target material that is a target irradiated with a laser beam to generate extreme ultraviolet light,
A pipe for supplying a liquid or gaseous target material;
A nozzle tip having a flange part integrated with the pipe part on the first surface, and jetting a target material supplied from the pipe part to the inflow port from the discharge port through the flow path;
A jet nozzle in which a projecting portion having a flow path is formed at the nozzle tip by providing the inlet at a position projecting from the first surface of the flange portion.   The jet nozzle according to claim 1, wherein an outer diameter of the protruding portion is reduced as it protrudes from the first surface of the flange portion.   In order to prevent the solid mixed in the target material from moving from the region between the protruding portion and the piping portion into the flow path of the protruding portion, the outer diameter of the protruding portion is The jet nozzle according to claim 1, wherein the jet nozzle is increased at a predetermined distance from the first surface than at a position less than the predetermined distance.   4. The jet nozzle according to claim 3, wherein an outer diameter of the protruding portion becomes smaller as it protrudes from the first surface of the flange portion at a position of a predetermined distance or more from the first surface of the flange portion.   In order to prevent solids mixed in the target material from moving from the region between the protruding portion and the piping portion into the flow path of the protruding portion, the inner diameter of the piping portion is set at the tip of the nozzle. The jet nozzle according to any one of claims 1 to 4, wherein the jet nozzle is reduced at a predetermined distance from the first surface of the flange portion than at a position less than the predetermined distance.   The jet nozzle according to any one of claims 1 to 5, wherein the discharge port is formed at a position that does not protrude from a second surface facing the first surface of the flange portion.   The flow path is formed in a taper shape by reducing the inner diameter of the flow path in at least a part of the nozzle tip from the inflow port toward the discharge port. The jet nozzle according to item. A light source device that generates extreme ultraviolet light by irradiating a target with a laser beam,
The jet nozzle according to any one of claims 1 to 7,
A target supply unit for supplying a liquid or gaseous target material to the piping unit;
A laser unit for generating plasma by irradiating a target material ejected from the nozzle tip with a laser beam;
A condensing optical system that condenses and emits extreme ultraviolet light emitted from the plasma;
A light source device comprising:

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