JP2022553502A - Conductive material for discharge laser - Google Patents

Abstract

An excimer laser comprising a discharge chamber (12) and a conductive member (22) for conducting a current associated with a discharge in the discharge chamber of the laser, the conductive member being located at the ends (32, 34) of the conductive member. The conductive member includes at least one channel (26a-26d) configured to increase the current flow path relative to the current flow path in the central portion (34) of the conductive member, the conductive member connecting the laser to the voltage source (24). ) and to provide an interface between the voltage source and the discharge chamber of the laser. [Selection diagram] Figure 5

Description

Cross-reference to related applications
[0001] This application claims priority to U.S. Application No. 62/914,359, filed October 11, 2019, entitled CONDUCTIVE MEMBER FOR DISCHARGE LASER, which application is incorporated by reference in its entirety. incorporated herein by.

[0001] The present invention relates to conductive members, associated apparatus, systems and methods for conducting current associated with a discharge in a discharge chamber of a laser.

[0002] A lithographic apparatus is a machine constructed to apply a desired pattern onto a substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithographic apparatus maps, for example, a pattern (often referred to as a "design layout" or "design") in a patterning device (e.g. mask) onto a layer of radiation-sensitive material (resist) provided on a substrate (e.g. a wafer). can be projected onto

[0003] As the semiconductor manufacturing process continues to advance, the dimensions of circuit elements have continued to shrink, while the amount of functional elements, such as transistors, per device is commonly referred to as "Moore's Law." Following the trend, it has steadily increased over the decades. In an effort to keep up with Moore's Law, the semiconductor industry is pursuing technologies that enable the creation of smaller and smaller features. A lithographic apparatus can use electromagnetic radiation to project a pattern onto a substrate. The wavelength of this radiation determines the minimum feature size that can be patterned on the substrate. Lower wavelengths allow the fabrication of smaller features on the substrate. Typical wavelengths currently in use are 365 nm (i-line), 248 nm, 193 nm and 13.5 nm. Lithographic apparatus using deep ultraviolet (DUV) radiation may operate at wavelengths of 193 or 248 nm, while lithographic apparatus using extreme ultraviolet (EUV) radiation may operate at wavelengths in the range of 4 nm to 20 nm, such as 6.7 nm or 13 nm. It can operate at a wavelength of 0.5 nm.

[0004] Gas discharge lasers may be used to produce DUV radiation. In such lasers, a cathode and an anode are typically spaced apart within the chamber of the laser. When a discharge occurs between the cathode and anode, current can flow from the cathode to the anode. Current may cause erosion of the cathode and/or anode, and the erosion may not be uniform. Non-uniform erosion of the cathode and/or anode can lead to shortened life of the cathode and/or anode, and thus of the laser chamber.

[0005] According to one aspect of the invention, a conductive member is provided for conducting a current associated with a discharge in a discharge chamber of a laser, the conductive member connecting a portion of the conductive member with a current flow path to another of the conductive member. the conductive member to connect the laser to the voltage source and between the voltage source and the discharge chamber of the laser. is configured to provide an interface to By increasing the current flow path of one portion of the conductive member relative to another portion of the conductive member, the current density or uniformity of current conducted through the conductive member may be enhanced. It has been found that this in turn can lead to improved uniformity of the current profile in the discharge chamber. Improved uniformity of the current profile in the discharge chamber provides more uniform erosion of the cathode and anode, which can lead to longer cathode, anode, and/or laser discharge chamber life.

[0006] The conductive member may comprise a plurality of channels. Each of the channels can be associated with a portion of the conductive member. Each of the channels may be configured to increase the current flow path of an associated portion of the conductive member relative to the current flow path of another portion of the conductive member.

[0007] The conductive member may comprise a first end. The first end may comprise at least one of the channels.

[0008] The first end may comprise a first rounded edge. The first end may comprise at least two of the channels. At least two of the channels may extend longitudinally inward from the first rounded edge.

[0009] The conductive member may comprise a second end. The second end may comprise at least one of the channels.

[00010] The second end may comprise a second rounded edge. The second end may comprise at least two of the channels. At least two of the channels may extend longitudinally inward from the second rounded edge.

[00011] The conductive member may be configured to connect to a plurality of charge storage devices. The conductive member may be configured to connect to multiple conductive elements. The conductive member may be configured to conduct current from each charge storage device of the plurality of charge storage devices to respective conductive elements of the plurality of conductive elements.

[00012] The conductive member may comprise a plurality of first connection points. The conductive member may comprise a plurality of second connection points. Each first connection point of the plurality of first connection points may be configured to connect to one charge storage device of the plurality of charge storage devices. Each second connection point of the plurality of second connection points may be configured to connect to one conductive element of the plurality of conductive elements.

[00013] The plurality of first connection points may be arranged in a longitudinally extending configuration along the conductive member. The plurality of second connection points may be arranged in a longitudinally extending configuration along the conductive member.

[00014] The conductive member may be configured such that each of the channels is disposed between one first connection point and one second connection point.

[00015] The conductive member may further comprise an insulating portion. An insulator may be disposed in each channel.

[00016] The conductive member may be or comprise a conductive bar.

[00017] According to another aspect of the invention, there is provided a laser comprising a discharge chamber and a conductive member for conducting current associated with the discharge in the discharge chamber, the conductive member being a portion of the conductive member. at least one channel configured to increase the current flow path relative to the current flow path of another portion of the conductive member, the conductive member connecting the laser to and from the voltage source; and the discharge chamber of the laser.

[00018] A laser may comprise a plurality of charge storage devices. A laser may comprise a plurality of conductive elements. A plurality of charge storage devices and a plurality of conductive elements may be connected to the conductive member.

[00019] The conductive member may be configured to conduct current from each charge storage device of the plurality of charge storage devices to a respective conductive element of the plurality of conductive elements.

[00020] The plurality of conductive elements may be configured to induce current into the discharge chamber.

[00021] The conductive member may comprise a plurality of channels. Each of the channels can be associated with a portion of the conductive member. Each of the channels may be configured to increase the current flow path of an associated portion of the conductive member relative to the current flow path of another portion of the conductive member.

[00022] The discharge chamber may be configured to hold one or more gases. The one or more gases may comprise krypton, argon, and/or fluorine.

[00023] The features of the conductive member of the above aspects may also be applied to or provided in the conductive member of this aspect.

[00024] According to another aspect of the invention, a radiation source comprising a laser comprising a discharge chamber and a conducting member according to any of the above aspects for conducting a current associated with the discharge in the discharge chamber; and a lithographic apparatus. A lithography system is provided comprising:

[00025] According to another aspect of the invention, a method of operating a laser is provided, the laser having a laser discharge chamber and a conductive member for conducting current associated with the discharge in the discharge chamber. with at least one channel configured to increase the current flow path of one portion of the conductive member relative to the current flow path of another portion of the conductive member, connecting the laser to a voltage source; a conductive member providing an interface between the voltage source and the discharge chamber of the laser, the method forming a discharge in the discharge chamber such that a current associated with the discharge flows through the conductive member and into the discharge chamber. applying a voltage to the conductive member to cause the

[00026] A laser may comprise a plurality of charge storage devices. A laser may comprise a plurality of conductive elements. A plurality of charge storage devices and a plurality of conductive elements may be connected to the conductive member.

[00027] The conductive member may be configured to conduct current from each charge storage device of the plurality of charge storage devices to a respective conductive element of the plurality of conductive elements. A plurality of conductive elements may be configured to induce current into the discharge chamber.

[00028] Applying a voltage to the conductive member causes a current flow path from one of the plurality of charge storage devices of the portion of the conductive member to an associated one of the plurality of conductive elements to , a plurality of charge storage devices that are longer than the current path from one of the plurality of charge storage devices in another portion of the conductive member to an associated one of the plurality of conductive elements. Current may flow from the device to a plurality of conductive elements through the conductive member.

[00029] Applying a voltage to the conductive member may cause current to flow from the plurality of conductive elements into the discharge chamber.

[00030] Applying a voltage to the conductive member may comprise applying a negative potential to the conductive member.

[00031] The conductive member may comprise a plurality of channels. Each of the channels can be associated with a portion of the conductive member. Each of the channels may be configured to increase the current flow path of an associated portion of the conductive member relative to the current flow path of another portion of the conductive member.

[00032] The conductive member may further comprise an insulator disposed in each channel.

[00033] The features of the conductive member of the above aspects may also be applied to or provided in the conductive member of this aspect.

[00034] Various aspects and features of the invention described above or below can be combined with various other aspects and features of the invention, as will be readily apparent to those skilled in the art.

[00035] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings.

[00036] Figure 1 depicts a schematic overview of a lithographic system comprising a radiation source and a lithographic apparatus; [00037] Figure 2 depicts a cross-sectional view of a portion of a laser that may be used in the lithography system of Figure 1; [00038] Fig. 3 illustrates an exemplary embodiment of a conductive member for use with the laser of Fig. 2; [00038] Fig. 3 illustrates an exemplary embodiment of a conductive member for use with the laser of Fig. 2; [00039] FIG. 3B illustrates a plan view of the conductive member of FIG. 3A. [00040] Fig. 4B illustrates a first end of an embodiment of the conductive member of Fig. 4A. [00041] Fig. 3 illustrates a first end of another exemplary conductive member for use with the laser of Fig. 2; [00042] FIG. 3 depicts a partially exploded view of a laser chamber containing a portion of the laser of FIG. [00043] FIG. 6 illustrates a cross-sectional view of a portion of the laser of FIG. [00044] Figure 6 illustrates a portion of the laser of Figure 5; [00045] Fig. 5 depicts a flowchart outlining steps of a method of operating a laser.

[00046] Figure 1 schematically depicts a lithographic system comprising a source SO and a lithographic apparatus LA. The lithographic apparatus LA may support an illumination system (also called illuminator) IL configured to condition a radiation beam B (e.g. UV, DUV or EUV radiation), and a patterning device (e.g. mask) MA. holding a substrate (e.g. resist-coated wafer) W and a mask support (e.g. mask table) MT connected to a first positioner PM constructed in and configured to accurately position the patterning device MA according to certain parameters and a substrate support (e.g. wafer table) WT connected to a second positioner PW configured to position the substrate support accurately according to certain parameters, and the patterning device MA to the radiation beam B. a projection system (eg a refractive projection lens system) PS configured to project an imparted pattern onto a target portion C (eg comprising one or more dies) of a substrate W;

[00047] In operation, the illumination system IL receives a beam of radiation from the source SO, for example via the beam delivery system BD. The illumination system IL may comprise refractive, reflective, magnetic, electromagnetic, electrostatic and/or other types of optical components or their components for directing, shaping and/or controlling radiation. Various types of optical components can be included in any combination. The illuminator IL may be used to condition the beam of radiation B so that its cross section has a desired spatial and angular intensity distribution in the plane of the patterning device MA.

[00048] As used herein, the term "projection system" PS includes, for example, a refractive optical system, a refractive optical system, as appropriate for the exposure radiation used and/or other factors such as the use of immersion liquid and the use of a vacuum. Broadly defined to cover various types of projection systems including reflective optical systems, catadioptric optical systems, anamorphic optical systems, magneto-optical systems, electromagnetic-optical systems and/or electrostatic optical systems, or any combination thereof should be interpreted. Any use of the term "projection lens" herein may be considered synonymous with the more general term "projection system" PS.

[00049] The lithographic apparatus LA may be of a type in which at least part of the substrate may be covered with a liquid having a relatively high refractive index, such as water, so as to fill the space between the projection system PS and the substrate W. This is also called immersion lithography. Further information on immersion techniques is found in US Pat. No. 6,952,253, incorporated herein by reference.

[00050] The lithographic apparatus LA may be of a type having more than one substrate support WT (also called "dual stage"). In such a "multi-stage" machine substrate supports WT may be used in parallel and/or other substrates W on other substrate supports WT exposing patterns on other substrates W A step of preparing the substrate W for a subsequent exposure may be performed on the substrate W located on one of the substrate supports WT while it is in use for exposure.

[00051] In addition to the substrate support WT, the lithographic apparatus LA may comprise a measurement stage. A measurement stage is arranged to hold the sensor and/or the cleaning device. The sensors may be arranged to measure properties of the projection system PS or properties of the radiation beam B. FIG. The measurement stage may hold multiple sensors. The cleaning device may be arranged to clean a part of the lithographic apparatus, for example a part of the projection system PS or a part of the system providing immersion liquid. The measurement stage may move under the projection system PS when the substrate support WT is away from the projection system PS.

[00052] In operation, the beam of radiation B is incident on the patterning device, eg mask MA, held by the mask support MT and is patterned according to the pattern (design layout) present on patterning device MA. After passing through the mask MA, the radiation beam B passes through the projection system PS, which focuses the beam onto a target portion C of the substrate W. FIG. With the help of a second positioner PW and a position measuring system IF, the substrate support WT is e.g. can move accurately. Similarly, the patterning device MA may be accurately positioned with respect to the path of the radiation beam B using the first positioner PM and possibly another position sensor (not explicitly shown in FIG. 1). Patterning device MA and substrate W may be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2. Although the substrate alignment marks P1, P2 are shown occupying dedicated target portions, they may be located in spaces between target portions. When positioned between target portions C, substrate alignment marks P1, P2 are referred to as scribe-lane alignment marks.

[00053] FIG. 2 shows part of a laser 10 used in a lithographic system, such as the lithographic system shown in FIG. The laser 10 may be part of the source SO or may be provided with the source SO. Laser 10 may be provided in the form of a gas discharge laser, for example an excimer laser. Laser 10 includes discharge chamber 12 . Laser 10 includes a first electrode 14, which may be a cathode. Laser 10 includes a second electrode 16, which may be an anode. Cathode 14 and anode 16 are positioned within discharge chamber 12 . Cathode 14 and anode 16 are spaced apart and opposed to each other. Anode 16 may be positioned opposite cathode 14 on support member 16b. Support member 16b may be provided in the form of an anode support bar. Other configurations for positioning the first and second electrodes may be used in other embodiments.

[00054] The discharge chamber 12 may be configured to hold one or more gases 18, such as, for example, gas mixtures. Gas 18 may comprise noble gases, such as argon, krypton, or xenon, and reactive gases, such as fluorine or chlorine.

[00055] When a voltage is applied between the cathode 14 and the anode 16, a discharge can occur in the discharge region 20 between the cathode 14 and the anode 16. FIG. The discharge can ionize the gases 18 within the chamber 12, which can cause chemical reactions between the gases. For example, a gas mixture of argon and fluoride can chemically produce excited molecule argon fluoride, which exists only in an excited state and can decay rapidly. An excited molecule can release excess energy by emitting a photon, thereby returning to its ground state and dissociating into the original free atom. The photons created during the discharge may then be reflected by one or more optical components (not shown) within the chamber and then guided out of laser 10 as laser pulses. It will be appreciated that in other embodiments, other gas mixtures may be used, such as krypton and fluoride gas mixtures.

[00056] In some embodiments, the gas mixture 18 may be pre-ionized to create the required electron density prior to discharge. The laser may comprise a pre-ionization device 21, which may be configured to produce ultraviolet light for ionizing the gas mixture 18 prior to discharge.

[00057] The laser 10 may comprise a plurality of insulating parts or components 19; The insulating part or component 19 may comprise a ceramic material, for example aluminum oxide _{( Al2O3} or _AlO2 ). Alternatively, the insulating part or component 19 may comprise a plastic material, which may comprise a polymer or polymer compound, for example Teflon. Insulating parts or components 19 may be variously arranged within the discharge chamber, for example, to electrically insulate the cathode 14 and anode 16 from the rest of the discharge chamber 12 .

[00058] The laser 10 may include other components for supplying one or more of the gases, for circulating the gases within the discharge chamber, for adjusting the temperature within the discharge chamber, and/or for the like. It will be appreciated that the These are not shown in FIG. 2 for purposes of clarity.

[00059] The laser 10 comprises a conductive member 22 for conducting the current associated with the discharge in the discharge chamber 12. As shown in FIG. In other words, current can flow through the conductive member 22 when there is a discharge in the discharge chamber. Current may flow through conductive member 22 into discharge chamber 12 . For example, current may flow through conductive member 22 to cathode 14 and from cathode 14 to anode 16, as described below. Conductive member 22 is configured to connect laser 10 to voltage source 24 and to provide an interface between voltage source 24 and discharge chamber 12 of laser 10 . In other words, cathode 14 and/or anode 16 may be energized through conductive member 22 . Conductive members 22 may be provided in the form of conductive bars. Conductive member 22 may comprise a metal such as aluminum, for example. Conductive member 22 may include a coating. The coating may comprise a fluorine resistant material. As an example, the coating may comprise a transition metal such as nickel.

[00060] FIGS. 3A and 3B illustrate an exemplary embodiment of a conductive member 22 for use with a laser, such as laser 10 shown in FIG. Conductive member 22 includes at least one channel 26 configured to increase the current flow path of first portion 28 of conductive member 22 relative to the current flow path of second portion 30 of conductive member 22 . Channel 26 may alternatively or additionally be configured to increase the current flow path of third portion 32 of conductive member 22 relative to the current flow path of second portion 30 of conductive member 22 . In other words, the channels 26a cause the current to follow a longer path in the first portion 28 of the conducting member 22 than in the second portion 30 of the conducting member 22. can be configured to This may result in improved current density or current uniformity in the conductive member 22 . It has been found that this in turn can lead to improved uniformity of the current profile in the discharge chamber 12 . The term “current profile” can be considered to encompass current and/or current density along cathode 14 and/or anode 16, eg, along the length of cathode 14 and/or anode 16. FIG. Improved uniformity of the current profile in the discharge chamber can provide more uniform erosion of the cathode and anode, which can lead to longer cathode, anode, and/or laser discharge chamber life.

[00061] The conductive member 22 comprises a plurality of channels 26a-26d, four of which are shown in Figures 3A and 3B. It will be appreciated, however, that the number of channels may be selected based on the desired or required current profile in the discharge chamber 12 and/or the desired or required current density in the conductive member 22. . It will also be appreciated that in other embodiments the conductive member may comprise more or less than four channels.

[00062] Each of the channels 26a-26d may be associated with the first portion 28 or the third portion 32 of the conductive member 22. As shown in FIG. Each of channels 26 a - 26 d is configured to increase the current flow path of the associated portion of conductive member 22 relative to the current flow path of the other portion of conductive member, second portion 30 . . In the embodiment shown in FIGS. 3A and 3B, two channels 26a, 26b are associated with first portion 28 of conductive member 22. In the embodiment shown in FIGS. Each of the two channels 26 a , 26 b may be configured to increase the current flow path of the first portion 28 of the conductive member 22 as compared to the current flow path of the second portion 30 of the conductive member 22 . Two additional channels 26 c , 26 d may be associated with the third portion 32 of the conductive member 22 . Again, each of the two additional channels 26c, 26d is configured to increase the current flow path in the third portion 32 of the conductive member 22 as compared to the current flow path in the second portion 30 of the conductive member 22. obtain. The first, second and third portions 28, 30, 32 are indicated by dashed lines in FIGS. 3A and 3B.

[00063] Conductive member 22 may be configured such that two channels 26a, 26b extend parallel to each other and/or two further channels 26c, 26d extend parallel to each other, as shown in Figures 3A and 3B. can be configured as Each of the two channels 26 a , 26 b and/or each of the further two channels 26 c , 26 d may be arranged to extend along the axis or longitudinal direction A of the conductive member 22 .

[00064] Parameters such as the dimensions and configuration of channels 26a, 26b and two further channels 26c, 26d are selected based on the current profile required in discharge chamber 12 or the current density required in conductive member 22. can be The parameters may include the length L and width W of each channel 26a, 26b and each further channel 26c, 26d, as indicated in Figure 3A. The length of each channel 26a, 26b and/or each further channel 26c, 26d can range from about 3 to 20 cm in some embodiments, although other dimensions are used in other embodiments. can be The width of each channel 26a, 26b and/or each further channel 26c, 26d may be in the range of about 0.5 to 1.3 cm in some embodiments, while in other embodiments other Dimensions can be used. Each of the channels 26a-26d may all have the same dimensional parameters, or may be different.

[00065] The conductive member 22 may comprise a first end 34. As shown in FIG. First portion 28 of conductive member 22 may define or be part of first end 34 of conductive member 22 . In this embodiment, first end 34 includes two channels 26a, 26b. It will be appreciated that in other embodiments the first end may comprise less or more than two channels. First end 34 may comprise a first rounded edge 34a. Conductive member 22 may be configured such that two channels 26a, 26b extend longitudinally inwardly from first rounded edge 34a.

[00066] The conductive member 22 may comprise a second end 36. As shown in FIG. Third portion 32 of conductive member 22 may define or be part of second end 36 of conductive member 22 . In this embodiment the second end 36 comprises two further channels 26c, 26d. It will be appreciated that in other embodiments the second end may comprise more or less than two additional channels. The second end 36 may comprise a second first rounded edge 36a. Conductive member 22 may be configured such that two additional channels 26c, 26d extend longitudinally inwardly from second rounded edge 36a. One or all of the channels 26a-26d may extend longitudinally inwardly from the first and second rounded edges 34a, 36a. Conductive member 22 is configured such that first and second rounded edges 34a, 36a are positioned opposite each other.

[00067] Without the channels 26a-26d, increased current may flow at the first and/or second ends 34, 36 relative to the current flowing in the remainder of the conductive member 22, eg, during use. Experiments show that. Stated another way, in use, the current density at the first and/or second ends 34, 36 will be higher than the current density at the remainder of the conductive member 22. FIG. By providing channels 26a, 26b as part of first end 34 and/or additional channels 26c, 26d as part of second end 36 of conducting member 22, the first and/or second The current density or current flowing through the two ends 34, 36 can be reduced. This may result in improved current density or uniformity of current flowing through conductive member 22 . This in turn can result in more uniform erosion of the cathode and/or anode, which can lead to longer cathode, anode and/or discharge chamber life.

[00068] Figure 3A shows an exemplary conductive member 22 that may be used with a discharge chamber 12 holding an argon fluoride gas mixture, but may also be used in conjunction with other gas mixtures. Conductive member 22 may be configured to conduct current associated with the discharge in discharge chamber 12, as described above. One or more dimensions of conductive member 22 may be selected based on the current profile that may be required or desired in discharge chamber 12 . Additionally or alternatively, the dimensions of conductive member 22 may be selected to minimize or reduce the inductance of conductive member 22, for example, when current flows through conductive member 22 in use. It will be appreciated that the dimensions may alternatively or additionally be selected based on one or more dimensions of the discharge chamber 12 and/or other portions of the laser 10 . In this embodiment, conductive member 22 may have a thickness T in the range of 20 to 50 mm, such as about 30 mm, although other thicknesses may be used in other embodiments. Conductive member 22 also includes two recesses 35a having a thickness less than thickness T. FIG. Conductive member 22 may have a length L1 and width W1 selected in relation to the dimensions of the discharge laser, and these may vary in various embodiments.

[00069] Although FIG. 3B shows an exemplary conductive member 22 as may be used with a discharge chamber 12 containing a gas mixture such as a krypton fluoride gas mixture, the exemplary conductive member 22 of FIG. It can also be used in connection with gas mixtures. The conductive member 22 shown in FIG. 3B is similar to that shown in FIG. 3A. However, it can be seen that the conductive member 22 shown in FIG. 3B is thinner than the conductive member 22 shown in FIG. 3A. In this embodiment, conductive member 22 may have a thickness in the range of 2 to 5 mm, such as about 3 mm, although other thicknesses may be used in other embodiments. The length L1 and width W1 of the conductive member 22 shown in FIG. 3B are selected in relation to the dimensions of the discharge laser, which may vary in various embodiments.

[00070] FIG. 4A depicts a plan view of the exemplary conductive member 22 shown in FIG. 3A. However, it will be appreciated that the features described below may also apply to the conductive member 22 shown in FIG. 3B. Conductive member 22 is configured to connect to voltage source 24 . Conductive member 22 may be configured to accommodate a portion of the connection arrangement for connecting the voltage source to the laser (not shown in FIG. 4A). Conductive member 22 may include two recesses 35a. The two recesses 35a can be thought of as recessing downward into the plane of FIG. 4A. Two recesses 35a are more clearly visible in FIG. 3A. In some embodiments, recess 35a may be configured to accommodate at least a portion of the connection arrangement. The two recesses 35 a are arranged in the center or central portion 37 of the conductive member 22 . A central portion 37 of conducting member 22 may be part of or provided in second portion 30 of conducting member 22 . Each of the recesses 35a may be arranged to extend along an axial or longitudinal direction A. As shown in FIG. The width W2 of the central or central portion 37 may be greater than the width W1 of the remainder of the conductive member 22 (shown in FIG. 3A). Center or central portion 37 may be configured to allow a seal to be formed between conductive member 22 and another portion of laser 10 .

[00071] Conductive member 22 may be configured to connect to a plurality of charge storage devices and a plurality of conductive elements. For example, each charge storage device may be provided in the form of a capacitor as shown in FIG. However, it will be appreciated that other devices for storing charge may be used. Each conductive element may be provided with the value of a feedthrough element, although other conductive elements may be used in other embodiments. Conductive member 22 may be configured to direct current from each capacitor to a respective feedthrough.

[00072] Referring to FIG. 4A, the conductive member 22 may comprise a plurality of first connection points 38. In FIG. Each first connection point 38 may be configured to connect to a charge storage device, such as a capacitor. Each first connection point 38 may be provided in the form of a hole. A first connection point 38 is positioned along the axis or longitudinal direction A of the conductive member 22 . The first connection point 38 may be located near the outer edge or perimeter of the conductive member 22 . The first connection points 38 may be arranged on opposite sides of the conductive member 22 in two rows 38a, 38b. Some of the first connection points 38 may be located in recesses 35a, as shown in FIG. 4A.

[00073] The conductive member 22 may comprise a plurality of second connection points 40. As shown in FIG. Each second connection point 40 may be configured to connect to a feedthrough element. Each first connection point 38 is provided in the form of a further hole. The second connection points 40 may be arranged linearly along the axis or longitudinal direction A of the conductive member 22, although other arrangements may be used in other embodiments. The second connection point 40 may be arranged between the two rows 38a, 38b of the first connection points 38. As shown in FIG. Each second connection point 40 may be associated with a pair of first connection points 38 . Each second connection point 40 may be disposed between an associated pair of first connection points 38 .

[00074] Figure 4B shows the first end 34 of the conductive member shown in Figure 4A. Conductive member 22 may be configured such that each channel 26a, 26b extends between a first connection point 38 and a second connection point 40, the second connection point 40 having an associated first connection. Current can flow from point 38 . 4A, each channel 26a, 26b extends generally between two first connection points 38 and two second connection points 40. In the exemplary embodiment shown in FIG. When conductive member 22 is connected to a capacitor and feedthrough element in use, conductive member 22 may conduct current from one or a pair of capacitors to the associated feedthrough element. The current flow paths of the first and second portions 28, 30 of the conductive member are indicated by arrows in FIG. 4B. As shown in FIG. 4B, the current flow path in the first portion 28 of the conductive member 22 is longer than the current flow path in the second portion 30 . In other words, the channels 26a, 26b provide a longer path for current flow in the first portion 28 of the conductive member 22 than in the second portion 30 of the conductive member 22. can be configured to allow This can lead to improved uniformity of the current flowing through or the current density in the conductive member 22 . This in turn can result in a more uniform current or current density along the cathode 14 and/or anode 14, which can lead to more uniform erosion of the cathode and anode. This can lead to increased cathode, anode, and/or discharge chamber life.

[00075] FIG. 4C illustrates first end 34 of another exemplary embodiment of conductive member 22. FIG. The conductive member shown in FIG. 4C is similar to conductive member 22 described above. In this embodiment, the conductive member 22 has an insulating portion 42 . At least a portion of insulation 42 may be disposed in each of the two channels 26a, 26b. Insulation 42 may be configured to prevent current from flowing across each channel 26a, 26b or between two channels 26a, 26b. The isolation 42 may be configured based on the parameters of each channel 26a, 26b and/or the distance D between the two channels 26a, 26b. In this embodiment, the insulating portion 42 has a U shape. It will be appreciated that in other embodiments the insulation may have different shapes, for example depending on the parameters of each channel and/or the distance between the two channels. In other embodiments, the insulation may include two separate prongs 42a that are not joined to form a single piece. The insulating portion 42 may comprise two prongs 42a and/or a portion 42b connecting the two prongs 42a. The length L3 and/or width W3 of each prong 42a may be selected based on the length L and/or width W of each channel 26a, 26b. Stated another way, the length L3 and/or width W3 of each prong 42a may be selected to generally correspond to the length L and/or width W of each channel 26a, 26b. The insulating portion 42 may be positioned on the conductive member 22 such that, for example, each of the prongs 42a is positioned in each of the two channels 26a, 26b. With each prong 42a of insulating portion 42 positioned in each of the two channels 26a, 26b, portion 42b may cover portion 34b of first rounded edge 34a. A portion 34b of the first rounded edge 34a may extend between the two channels 26a, 26b.

[00076] The insulating portion may be formed of an insulating material. For example, the insulating material may comprise plastic material. The plastic material may comprise a polymer or polymer compound, for example Teflon. Alternatively, the insulating material may comprise a ceramic material such as aluminum oxide _{( Al2O3} or _AlO2 ). Insulation 42 may be placed in each channel 26a, 26b as described above to prevent the formation of an electrical arc or arcing between each channel 26a, 26b and/or between two channels 26a, 26b. It will be appreciated that the conductive member 22 may comprise additional insulation. Further insulation may comprise any of the features of insulation 42 . A further insulation may be arranged in each further channel 26c, 26d. Conductive member 22 may include insulation disposed in one or more of channels 26a-26d. One or all of channels 26a-26d may include insulation disposed therein.

[00077] FIG. 5 is a cutaway view illustrating an exemplary embodiment of laser 10. As shown in FIG. Laser 10 comprises a portion of the laser shown in FIG. Thus, the features described above with respect to FIG. 2 may also apply to the laser 10 shown in FIG.

[00078] FIG. 5 shows the exterior 12a of the discharge chamber 12 shown in FIG. The sheath 12a of the discharge chamber 12 may be provided in the form of a recess on the exterior of the discharge chamber 12. FIG. As noted above, laser 10 includes conductive member 22 . The conductive member 22 is configured to be attached to the exterior portion 12a of the discharge chamber. The conductive member 22 shown in FIG. 5 is identical to the conductive member 22 shown in FIGS. 4A and 4B. Thus, the features described above with respect to FIGS. 4A and 4B may also apply to the conductive member 22 shown in FIG.

[00079] Laser 10 includes a plurality of charge storage devices 44, which are provided in the form of a plurality of capacitors. Each capacitor 44 may have a capacitance in the range of 200 to 800 pF, although other capacitances may be used in other embodiments. The placement of capacitor 44 may correspond to the placement of first connection point 38 of conductive member 22 . In other words, the capacitor 44 may be arranged along the axis or longitudinal direction B of the laser 10 . The capacitors 44 can be arranged in two rows 44a, 44b on both sides of the exterior part 12a of the discharge chamber 12. As shown in FIG. Capacitor 44 may be connected to conductive member 22 using a plurality of conductive fasteners 46a, such as screws, pins, bolts, or the like. One of them is shown in FIG. Each fastener 46 a may be inserted into the first connection point to connect the capacitor to the conductive member 22 .

[00080] Laser 10 includes a plurality of conductive elements 48, which are provided in the form of a plurality of feedthrough elements. The placement of feedthrough element 48 may correspond to the placement of second connection point 40 on conductive member 22 . In other words, the feedthrough elements 48 may be arranged linearly along the axis or longitudinal direction B of the laser 10 as shown in FIG. Other arrangements may be used in other embodiments. A feedthrough element 48 may be placed between two rows 44a, 44b of capacitors 44. As shown in FIG. Feedthrough element 48 may be connected to conductive member 22 using a plurality of additional conductive fasteners 46b, such as screws, pins, bolts, or the like. One of them is shown in FIG. Each additional fastener 46b may be inserted into the second connection point to connect the feedthrough element 48 to the conductive member 22, although other fastening means may be used.

[00081] In some embodiments, the laser 10 may comprise an optional connecting member 45. As shown in FIG. Connection members 45 may be provided in the form of connection plates or interconnect plates. Connection plate 45 may be configured to be flexible. For example, connecting plate 45 may have a thickness of less than 1 mm, although other thicknesses are used in other embodiments. Connection plate 45 may comprise a conductive material. The electrically conductive material may comprise a metal or metal alloy, such as copper or brass. A connection plate 45 may be positioned between the conductive member 22 and the capacitor 44 and feedthrough element 48 . The connection plate 45 may have the same or similar shape and configuration as the conductive member 22, including the channels. 5, two channels 45a and 45b corresponding to the two channels of conductive member 22 are visible. It will be appreciated that the number of channels in connecting plate 45 may correspond to the number of channels in conductive member 22 . A connection plate 45 may be arranged to ensure contact between the conductive member 22 and the capacitor 44 and feedthrough element 48 . Connection plate 45 may include a plurality of further holes 45 a to allow, for example, capacitors 44 and feedthrough elements 48 to be connected to conductive member 22 through connection plate 45 .

[00082] Laser 10 may comprise a connection arrangement 47 for connecting a voltage source (not shown in FIG. 5) to laser 10, eg, conductive member 22. FIG. The connection arrangement 47 comprises at least two connection elements 47a. Each connecting element 47 may comprise a conductive material, such as metal. Each connecting element 47 a may be positioned in a respective recess 35 a of conductive member 22 . Connecting element 47a may be secured to conductive member 22 by another plurality of fasteners 47b, such as screws, pins, bolts, or the like. The connection arrangement 47 may comprise at least two further connection elements 47c. Two further connecting elements 47c may each be provided in the form of an elastic and/or flexible element such as a spring or coil spring or the like. Each further connecting element 47c can be arranged in a recess 47d of each connecting element 47a. Connecting element 47a and further connecting element 47c may comprise a conductive material. Conductive materials may comprise metals or metal alloys, such as tin, brass, copper, or the like. The connection arrangement 47 may comprise at least two sealing elements 47e, eg two gaskets. Each sealing element 47e may be arranged to surround a connecting element 47a and/or a further connecting element 47c. Expressed another way, each sealing element 47e can be arranged between the conductive member 22 and the connecting element 47a and/or the further connecting element 47c. A connection arrangement 47 may be provided to ensure contact between the voltage source and the conductive member 22 . It will be appreciated that any of a variety of other means for connecting the voltage source to the conductive member may be used in other embodiments.

[00083] FIG. 6 shows a cross-sectional view of a portion of laser 10 along a portion of line B in FIG. Cathode 14 and anode 16 of laser 10 may be configured to extend along the axis or longitudinal direction of laser 10 . Anode 16 is attached to support member 16b by a plurality of fastening elements 16c, which may be provided in the form of screws, pins, bolts, or the like. Feedthrough elements 48, three of which are shown in FIG. For example, feedthrough element 48 may be connected to cathode 14 of laser 10 . Each feedthrough element 48 may be arranged to extend into the discharge chamber 12 from the exterior portion 12 a of the discharge chamber 12 . This may allow voltage to be applied to cathode 14 through conductive member 22 and feedthrough element 48, as described below. Each of feedthrough elements 48 may be configured to seal at least a portion of discharge chamber 12 , for example to prevent escape of gas 18 from the interior of discharge chamber 12 . Each feedthrough element 48 may comprise fluorine resistant material. The fluorine resistant material may comprise metal alloys such as brass, for example.

[00084] FIG. 7 shows a portion of the laser 10 shown in FIG. As noted above, electrical discharge between cathode 14 and anode 16 may cause current to flow through one or more portions of laser 10 . The current flow paths are indicated by arrows in FIG.

[00085] As mentioned above, the voltage source 24 may be connected to the conductive member 22. As shown in FIG. In use, a voltage may be applied to the conductive member 22 to cause a discharge in the discharge chamber such that the current associated with the discharge flows through the conductive member 22 and into the discharge chamber 12 . The voltage applied to conductive member 22 may be in the range of 500 to 1500V.

Conductive member 22 may be connected to capacitor 44 and feedthrough element 48 . When a voltage is applied to conductive member 22, each capacitor 44 may be charged. Charging each capacitor 44 may result in an increased voltage between cathode 14 and anode 16 . This voltage may be applied to cathode 14 via feedthrough element 48 . For example, a negative potential may be applied to conductive member 22, resulting in feedthrough element 48 and cathode 14 being negatively charged. A negative potential applied to conductive member 22 may also cause at least a portion of each capacitor 44 to be negatively charged. This in turn can create an electric field between cathode 14 and grounded anode 16 . It will be appreciated that in other embodiments a positive potential may be applied to the anode. The electric field can ionize the gas mixture 18 between cathode a 14 and anode 16 . When gas mixture 18 is sufficiently ionized, gas breakdown can occur and a discharge can occur in discharge region 20 of discharge chamber 12 . This can result in a voltage V _CP drop across each of capacitors 44 and a voltage drop across cathode 14 and anode 16 . Current may flow from capacitor 44 to feedthrough element 48 through conductive member 22 . Current may flow from the feedthrough element 48 into the discharge chamber 12 , eg, to the cathode 14 and across the discharge region 20 to the anode 16 . As noted above, by configuring conductive member 22 to include at least one channel, current density or current uniformity in conductive member 22 may be improved. This in turn may result in improved uniformity of current or current density along cathode 14 and/or anode 16, eg, along the length of cathode 14 and/or anode 16. FIG. This improved current or current density uniformity can result in more uniform erosion of the cathode and anode, which can lead to longer cathode, anode, and/or laser discharge chamber life. Current may flow away from anode 16 to ground (not shown) using, for example, current return element 54 . Current return element 54 may be configured to ground anode 16 .

[00087] Figure 8 is a flowchart outlining the steps of a method of operating a laser, such as laser 10 described above. At step 105, the method comprises providing a discharge laser having a conductive member 22 as described above, and a voltage source.

[00088] In step 110, the method comprises applying a voltage to the conductive member with a voltage source. A voltage is applied to induce an electrical discharge within the discharge chamber of the laser to operate the laser and produce a laser beam as described above.

[00089] In step 115, the voltage applied to the conductive member causes current to flow from the laser's charge storage device, eg, capacitor 44, to the laser's conductive element, eg, feedthrough element 48, through the conductive member.

[00090] In step 120, the voltage applied to the conductive member causes current to flow from the feedthrough element 48 into the discharge chamber. For example, current may flow from the conductive element to the first electrode of the laser, eg cathode 14 . Current may flow from a laser first electrode to a laser second electrode, eg, anode 16 , across, eg, discharge region 20 .

[00091] Applying the voltage may comprise charging a charge storage device, such as a capacitor 44, and/or a conductive element. For example, as described above, a negative potential can be applied to the conductive member. As a result, the conductive member, the conductive element and at least a portion of each charge storage device can be negatively charged. This in turn can result in the first electrode of the laser, eg the cathode, being negatively charged.

[00092] The method may comprise pre-ionizing the gas mixture in the discharge chamber of the laser, for example prior to the discharge.

[00093] It will be appreciated that the features described above, for example in connection with Figure 7, may be applied to, or be part of, a method.

[00094] By forming channels in the conductive member as described above, uneven erosion of the cathode and/or anode may be reduced or prevented. Since the conductive member may be connected to the discharge chamber at the sheath, there is no fluorine exposure when the conductive member is removed from the discharge chamber sheath and/or when the conductive member is (re)attached to the discharge chamber sheath. Will. Also, as noted above, the formation of channels may have no or reduced impact on one or more structural or thermal properties of the conductive member.

[00095] The term "channel" may be considered to encompass an elongated depression or an elongated hollow space or portion.

[00096] It will be appreciated that the terms "current flow path" and "current flow path" can be used interchangeably.

[00097] It will be appreciated that references to a plurality of features may be used interchangeably with references to those features in the singular, such as "at least one" and/or "each." For example, feature singular forms such as "at least one" or "each" may be used interchangeably.

[00098] In this document, the terms "radiation" and "beam" refer to ultraviolet (e.g., wavelengths of 365 nm, 248 nm, 193 nm, 157 nm or 126 nm) and EUV (extreme ultraviolet radiation, e.g., about 5-100 nm). It is used to encompass all types of electromagnetic radiation, including those with a range of wavelengths.

[00099] The terms "reticle," "mask," or "patterning device," as used herein, provide an incoming radiation beam with a patterned cross section corresponding to the pattern to be produced on a target portion of a substrate. can be broadly interpreted to refer to a general purpose patterning device that can be used for The term "light valve" can also be used in this context. Besides classical masks (transmissive or reflective masks, binary masks, phase shift masks, hybrid masks, etc.), other examples of such patterning devices include programmable mirror arrays and programmable LCD arrays.

[000100] Although the text makes particular reference to the use of the lithographic apparatus in the manufacture of ICs, it should be understood that the lithographic apparatus described herein have other applications as well. Other possible applications are the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, flat panel displays, liquid crystal displays (LCDs), thin film magnetic heads, and the like.

[000101] Although specific reference is made herein to embodiments of the invention in relation to a lithographic apparatus, embodiments of the invention may also be used in other apparatuses or systems. Embodiments of the present invention may form part of a mask inspection apparatus, metrology apparatus, or any apparatus that measures or processes objects such as wafers (or other substrates) or masks (or other patterning devices). . These apparatuses are sometimes commonly referred to as lithography tools. Such lithography tools can use vacuum or ambient (non-vacuum) conditions.

[000102] Although the above refers specifically to the use of embodiments of the invention in connection with optical lithography, the invention may be used in other applications, such as imprint lithography, for example, and the context permits. It will be appreciated that insofar it is not limited to optical lithography.

[000103] Other aspects of the invention are described in the following numbered clauses.
1. A conductive member for conducting current associated with a discharge in a discharge chamber of a laser, comprising:
At least one channel configured to increase a current flow path of a portion of the conductive member relative to a current flow path of another portion of the conductive member, the conductive member connecting the laser to a voltage source. a conductive member configured to provide an interface between the voltage source and the discharge chamber of the laser.
2. The conductive member of clause 1, wherein the conductive member comprises a plurality of channels.
3. Each of the channels is associated with a portion of the conductive member and configured to increase the current flow path of the associated portion of the conductive member relative to the current flow path of another portion of the conductive member. the conductive member of clause 2.
4. 4. The conductive member of any of clauses 1-3, wherein the conductive member comprises a first end, the first end comprising at least one of the channels.
5. The first end has a first rounded edge and the first end has at least two of the channels extending longitudinally inwardly from the first rounded edge. , the conductive member of clause 4.
6. 6. The conducting member of any of clauses 4 or 5, wherein the conducting member comprises a second end, the second end comprising at least one of the channels.
7. The second end has a second rounded edge and the second end has at least two of the channels extending longitudinally inwardly from the second rounded edge. , the conductive member of clause 6.
8. 8. The conductive member of any of clauses 1-7, wherein the conductive member is configured to connect to a plurality of charge storage devices and a plurality of conductive elements.
9. 9. The conductive member of clause 8, wherein the conductive member is configured to conduct current from each charge storage device of the plurality of charge storage devices to a respective conductive element of the plurality of conductive elements.
10. The conductive member has a plurality of first connection points and a plurality of second connection points, each first connection point of the plurality of first connection points being one charge storage device of the plurality of charge storage devices. wherein each second connection point of the plurality of second connection points is configured to connect to one conductive element of the plurality of conductive elements .
11. 11. The conductive member of clause 10, wherein the plurality of first connection points and/or the plurality of second connection points are arranged in a configuration that each extends longitudinally along the conductive member.
12. 12. The conductive member of clause 10 or 11, wherein the conductive member is configured such that each channel is disposed between one first connection point and one second connection point.
13. 13. The conductive member of any of clauses 1-12, further comprising insulation disposed in each channel.
14. 14. The conducting member of any of clauses 1-13, wherein the conducting member comprises a conducting bar.
15. a discharge chamber;
a conductive member for conducting current associated with the discharge in the discharge chamber;
wherein the conductive member comprises:
At least one channel configured to increase a current flow path of a portion of the conductive member relative to a current flow path of another portion of the conductive member, the conductive member connecting the laser to a voltage source. and to provide an interface between a voltage source and a discharge chamber of the laser.
16. 16. The laser of clause 15, wherein the laser comprises a plurality of charge storage devices and a plurality of conductive elements, the plurality of charge storage devices and the plurality of conductive elements being connected to the conductive member.
17. 17. The laser of clause 16, wherein the conductive member is configured to conduct current from each charge storage device of the plurality of charge storage devices to respective conductive elements of the plurality of conductive elements.
18. 18. The laser of clause 16 or 17, wherein the plurality of conductive elements are configured to induce current into the discharge chamber.
19. The conductive member has a plurality of channels, each of which is associated with a portion of the conductive member and directs current flow through an associated portion of the conductive member to flow through another portion of the conductive member. 19. The laser of any one of clauses 15-18, configured to increase compared to the path.
20. 20. The laser of any one of clauses 15-19, wherein the discharge chamber is configured to hold one or more gases, the one or more gases comprising krypton, argon and/or fluorine.
21. A radiation source comprising a laser, the laser comprising:
a discharge chamber;
a conductive member for conducting current associated with a discharge in a discharge chamber according to any one of clauses 1 to 14;
a radiation source comprising
a lithographic apparatus;
A lithography system, comprising:
22. A method of operating a laser, the laser comprising:
a laser having a laser discharge chamber;
A conductive member for conducting current associated with a discharge in the discharge chamber, the conductive member being configured to increase the current flow path of at least one portion of the conductive member relative to the current flow path of another portion of the conductive member. a conductive member comprising a channel, connecting the laser to the voltage source and providing an interface between the voltage source and the discharge chamber of the laser, the method comprising:
A method comprising applying a voltage to a conductive member to create a discharge in a discharge chamber such that a current associated with the discharge flows through the conductive member and into the discharge chamber.
23. 23. The method of clause 22, wherein the laser comprises a plurality of charge storage devices and a plurality of conductive elements, the plurality of charge storage devices and the plurality of conductive elements being connected to the conductive member.
24. The conductive member is configured to conduct current from each charge storage device of the plurality of charge storage devices to a respective conductive element of the plurality of conductive elements, the plurality of conductive elements to direct current into the discharge chamber. 24. The method of clause 23, comprising:
25. Applying a voltage to the conductive member ensures that a current flow path from one of the plurality of charge storage devices in the portion of the conductive member to an associated one of the plurality of conductive elements is aligned with the conductive member. from the plurality of charge storage devices to the associated one of the plurality of conductive elements is longer than the current path from one of the plurality of charge storage devices to another portion of the plurality of charge storage devices. 25. The method of Clause 23 or 24, wherein the conductive element of clause 23 or 24 causes current to flow through the conductive member.
26. 26. The method of clause 25, wherein applying a voltage to the conductive member causes current to flow from the plurality of conductive elements into the discharge chamber.
27. 27. The method of any one of clauses 23-26, wherein applying a voltage to the conducting member comprises applying a negative potential to the conducting member.
28. The conductive member has a plurality of channels, each of which is associated with a portion of the conductive member and directs current flow through an associated portion of the conductive member to flow through another portion of the conductive member. 28. The method of any one of clauses 22-27, wherein the method is configured to increase compared to the path.
29. 30. The method of any one of clauses 22-29, wherein the conductive member further comprises an insulation disposed in each channel.

[000104] While specific embodiments of the invention have been described above, it will be appreciated that the invention may be practiced otherwise than as described. The above description is illustrative, not limiting. It will therefore be apparent to one skilled in the art that modifications can be made to the invention as described without departing from the scope of the claims set forth below.

Claims (30)

A conductive member for conducting current associated with a discharge in a discharge chamber of a laser, comprising:
at least one channel configured to increase a current flow path of a portion of said conductive member relative to a current flow path of another portion of said conductive member, said conductive member energizing said laser; A conductive member configured to connect to a voltage source and to provide an interface between said voltage source and said discharge chamber of said laser. 2. The conductive member of Claim 1, wherein said conductive member comprises a plurality of said channels. Each of the channels is associated with a portion of the conductive member and compares the current flow path of the associated portion of the conductive member to the current flow path of the other portion of the conductive member. 3. The conductive member of claim 2, wherein the conductive member is configured to increase with increasing force. 2. The conductive member of Claim 1, wherein said conductive member comprises a first end, said first end comprising at least one of said channels. said first end having a first rounded edge, said first end having at least two of said channels extending longitudinally inwardly from said first rounded edge; 5. The conductive member of claim 4, comprising: 5. The conductive member of claim 4, wherein said conductive member comprises a second end, said second end comprising at least one of said channels. said second end having a second rounded edge, said second end having at least two of said channels extending longitudinally inwardly from said second rounded edge; 7. The conductive member of claim 6, comprising: 2. The conductive member of Claim 1, wherein the conductive member is configured to connect to a plurality of charge storage devices and a plurality of conductive elements. 9. The conductive member of Claim 8, wherein the conductive member is configured to conduct current from each charge storage device of the plurality of charge storage devices to a respective conductive element of the plurality of conductive elements. The conductive member comprises a plurality of first connection points and a plurality of second connection points, each first connection point of the plurality of first connection points being one of the plurality of charge storage devices. 3. The method of claim 1, wherein the second connection point is configured to connect to a charge storage device, each second connection point of the plurality of second connection points being configured to connect to one conductive element of the plurality of conductive elements. 9 conductive member; 11. The conductive member of claim 10, wherein the plurality of first connection points and/or the plurality of second connection points are arranged in a configuration that each extends longitudinally along the conductive member. 12. The conductive member of claim 11, wherein the conductive member is configured such that each of the channels is disposed between one first connection point and one second connection point. 3. The conductive member of Claim 2, further comprising an insulator disposed in each channel. 4. The conductive member of Claim 3, wherein said conductive member comprises a conductive bar. a discharge chamber;
a conductive member for conducting current associated with the discharge in the discharge chamber;
wherein the conductive member comprises:
at least one channel configured to increase a current flow path of a portion of said conductive member relative to a current flow path of another portion of said conductive member, said conductive member energizing said laser; A laser configured to connect to a voltage source and to provide an interface between said voltage source and said discharge chamber of said laser. 16. The laser of Claim 15, wherein said laser comprises a plurality of charge storage devices and a plurality of conductive elements, said plurality of charge storage devices and said plurality of conductive elements being connected to said conductive member. 17. The laser of Claim 16, wherein the conductive member is configured to direct the current from each charge storage device of the plurality of charge storage devices to each conductive element of the plurality of conductive elements. 17. The laser of Claim 16, wherein said plurality of conductive elements are configured to direct said current into said discharge chamber. The conducting member comprises a plurality of said channels, each of said channels being associated with a portion of said conducting member and providing a current flow path for said associated portion of said conducting member. 16. The laser of Claim 15, configured to increase said current flow path relative to said another portion. 19. The laser of Claim 18, wherein said discharge chamber is configured to hold one or more gases, said one or more gases comprising krypton, argon, and/or fluorine. A radiation source comprising a laser, said laser comprising:
a discharge chamber;
14. A conductive member for conducting current associated with a discharge in the discharge chamber of claim 13;
a radiation source comprising
a lithographic apparatus;
A lithography system, comprising: A method of operating a laser, said laser comprising:
a laser having a laser discharge chamber;
A conductive member for conducting a current associated with a discharge in the discharge chamber, the conductive member configured to increase a current flow path of a portion of the conductive member relative to a current flow path of another portion of the conductive member. a conductive member for connecting said laser to a voltage source and providing an interface between said voltage source and said discharge chamber of said laser; teeth,
applying a voltage to the conductive member to induce a discharge in the discharge chamber such that current associated with the discharge flows through the conductive member and into the discharge chamber. 23. The method of Claim 22, wherein said laser comprises a plurality of charge storage devices and a plurality of conductive elements, said plurality of charge storage devices and said plurality of conductive elements being connected to said conductive member. A conductive member is configured to direct the current from each charge storage device of the plurality of charge storage devices to a respective conductive element of the plurality of conductive elements, the plurality of conductive elements directing the current to the discharge chamber. 24. The method of claim 23, wherein the method is configured to guide in. The applying of the voltage to the conductive member may be performed from one charge storage device of the plurality of charge storage devices of the portion of the conductive member to an associated one of the plurality of conductive elements. said current path is from said current path from one of said plurality of charge storage devices of said another portion of said conductive member to an associated one of said plurality of conductive elements; 24. The method of claim 23, wherein current is caused to flow from the plurality of charge storage devices to the plurality of conductive elements through the conductive member such that the length of the conductive member increases. 26. The method of Claim 25, wherein said applying said voltage to said conductive member causes current to flow from said plurality of conductive elements into said discharge chamber. 24. The method of Claim 23, wherein the step of applying the voltage to the conducting member comprises applying a negative potential to the conducting member. The conducting member comprises a plurality of said channels, each of said channels being associated with a portion of said conducting member and providing a current flow path for said associated portion of said conducting member. 24. The method of claim 23, configured to increase said current flow path relative to said another portion. 23. The method of Claim 22, wherein the conductive member further comprises an insulator disposed in each channel. 29. The method of Claim 28, wherein the conductive member further comprises an insulator disposed in each channel.

Images