Abstract: A target delivery system for an extreme ultraviolet (EUV) light source is disclosed. The system includes: a conduit including an orifice configured to fluidly couple to a reservoir; an actuator configured to mechanically couple to the conduit such that motion of the actuator is transferred to the conduit; and a control system coupled to the actuator, the control system being configured to: determine an indication of pressure applied to target material in the reservoir, and control the motion of the actuator based on the determined indication of applied pressure. Moreover, techniques for operating a supply system are disclosed. For example, one or more characteristics of the supply system are determined, and an actuator that is mechanically coupled to the supply system is controlled based on the one or more determined characteristics such that an orifice of the supply system remains substantially free of material damage during operational use.

Abstract: A target delivery system for an extreme ultraviolet (EUV) light source is disclosed. The system includes: a conduit including an orifice configured to fluidly couple to a reservoir; an actuator configured to mechanically couple to the conduit such that motion of the actuator is transferred to the conduit; and a control system coupled to the actuator, the control system being configured to: determine an indication of pressure applied to target material in the reservoir, and control the motion of the actuator based on the determined indication of applied pressure. Moreover, techniques for operating a supply system are disclosed. For example, one or more characteristics of the supply system are determined, and an actuator that is mechanically coupled to the supply system is controlled based on the one or more determined characteristics such that an orifice of the supply system remains substantially free of material damage during operational use.

Abstract: Disclosed is a system for generating EUV radiation in which current flowing through target material in the orifice 320 of a nozzle in a droplet generator is controlled by providing alternate lower impedance paths for the current and/or by limiting a high frequency component of a drive signal applied to the droplet generator.

Abstract: A method includes ejecting initial droplets of a material using a nozzle. The method includes applying a pressure on the nozzle using an electromechanical element. The method includes controlling the applied pressure on the nozzle using an electrical signal generated by a waveform generator. The electrical signal includes a first periodic waveform and a second periodic waveform. The method includes coalescing the initial droplets to generate coalesced droplets based on the first and second periodic waveforms and drag. The method includes generating a detection signal, using a detector, corresponding to time intervals between crossings of coalesced droplets at the detector. The method includes determining at least first and second ones of the time intervals using a processor.

Abstract: Apparatus for and method of controlling formation of droplets used to generate EUV radiation. The droplet source includes a fluid exiting an nozzle and a sub-system having an electro-actuatable element producing a disturbance in the fluid. The droplet source produces a stream that breaks down into droplets that in turn coalesce into larger droplets as they progress towards the irradiation region. The electro-actuatable element is driven by a control signal having a sine wave component and a square wave component. Various parameters such as a phase difference between the sine wave component and the square wave component are measured and controlled to minimize the formation of noncoalesced satellite droplets in the stream.

Abstract: An apparatus includes: a tube; a body including: a first body wall and a second body wall; and a support structure including: a first support portion and a second support portion. The first body wall extends in a first direction, the second body wall extends in a second direction that is different than the first direction, a first portion of the tube passes through an opening in the second body wall the first support portion is configured to attach to the first body wall, and a second portion of the tube is configured to pass through the second support portion when the first support portion is attached to the first body wall. An interior of the tube and an interior of the body are configured to receive molten target material, and the target material emits extreme ultraviolet (EUV) light when in a plasma state.

Abstract: A fluid control device (100) includes a structure (120) defining a valve cavity, a first fluid port (135), a second fluid port (140), and a third fluid port (145) configured to be fluidly coupled to a hermetic interior (105) of a body; and a plunger valve (130) within the valve cavity and configured to move between first and second modes while maintaining the hermetic interior of the body. In the first mode, the plunger valve is open such that a first fluid flow path is open between the hermetic interior and the first fluid port and fluid is free to pass between the first fluid port and the hermetic interior. In the second mode, the plunger valve is closed such that the first fluid port is blocked from the hermetic interior by the plunger valve and a second fluid flow path is open between the hermetic interior and the second fluid port.

Abstract: A target delivery system for an extreme ultraviolet (EUV) light source is disclosed. The system includes: a conduit including an orifice configured to fluidly couple to a reservoir; an actuator configured to mechanically couple to the conduit such that motion of the actuator is transferred to the conduit; and a control system coupled to the actuator, the control system being configured to: determine an indication of pressure applied to target material in the reservoir, and control the motion of the actuator based on the determined indication of applied pressure. Moreover, techniques for operating a supply system are disclosed. For example, one or more characteristics of the supply system are determined, and an actuator that is mechanically coupled to the supply system is controlled based on the one or more determined characteristics such that an orifice of the supply system remains substantially free of material damage during operational use.

Abstract: Provided is an apparatus for and method of controlling formation of droplets (102a, b) used to generate EUV radiation that comprise an arrangement producing a laser beam directed to an irradiation region and a droplet source. The droplet source (92) includes a fluid exiting an nozzle (98) and a sub-system having an electro-actuatable element (104) producing a disturbance in the fluid (96). The droplet source produces a stream (100) that breaks down into droplets that in turn coalesce into larger droplets as they progress towards the irradiation region. The electro-actuatable element is driven by a hybrid waveform that controls the droplet generation/coalescence process. Also disclosed is a method of determining the transfer function for the nozzle.

Abstract: Disclosed is a system for generating EUV radiation in which current flowing through target material in the orifice 320 of a nozzle in a droplet generator is controlled by providing alternate lower impedance paths for the current and/or by limiting a high frequency component of a drive signal applied to the droplet generator.

Abstract: Provided is an apparatus for and method of controlling formation of droplets (102a, b) used to generate EUV radiation that comprise an arrangement producing a laser beam directed to an irradiation region and a droplet source. The droplet source (92) includes a fluid exiting an nozzle (98) and a sub-system having an electro-actuatable element (104) producing a disturbance in the fluid (96). The droplet source produces a stream (100) that breaks down into droplets that in turn coalesce into larger droplets as they progress towards the irradiation region. The electro-actuatable element is driven by a hybrid waveform that controls the droplet generation/coalescence process. Also disclosed is a method of determining the transfer function for the nozzle.

Abstract: The invention relates to a droplet dispensing device (4) comprising a reservoir (9) for containing a liquid medium (10), an outlet (11) for dispensing droplets of said liquid medium (10) from said reservoir (9), an actuation means (12) for generating and transmitting a mechanical oscillation at an excitation frequency, and a resonant structure comprising a piston (15) coupled to said actuation means (12) for transmitting said mechanical oscillation to the liquid medium (10) contained in said reservoir (9) such that droplets are formed from said liquid medium (10), wherein a resonance frequency of said resonant structure is sufficiently close to said excitation frequency, such that resonance occurs. The invention further relates to a UV or X-ray light source, comprising a droplet dispensing device (4) according to the invention, and a method for providing a stream, in particular a monodisperse stream, of droplets by means of the droplet dispensing device (4).

Abstract: The invention relates to a device (100) for generating UV or X-ray radiation (R) by means of a plasma (10), comprising a first compartment (110), a dispensing device (5), which is adapted to provide a target material (80) in the first compartment (10), an excitation light source (13) for providing an excitation light beam (90), and a buffer gas inlet (130) and/or a buffer gas outlet (140) for providing a buffer gas flow (B) along the direction (D) of the excitation light beam (90) in the first compartment (110), wherein the first compartment (110) is adapted to be at least partially heated by a heating device (150). The invention further relates to a method for generating UV or X-ray radiation (R) by means of the device (100).

Abstract: The invention relates to a device (100) for generating UV or X-ray radiation (R) by means of a plasma (10), comprising a first compartment (110), a dispensing device (5), which is adapted to provide a target material (80) in the first compartment (10), an excitation light source (13) for providing an excitation light beam (90), and a buffer gas inlet (130) and/or a buffer gas outlet (140) for providing a buffer gas flow (B) along the direction (D) of the excitation light beam (90) in the first compartment (110), wherein the first compartment (110) is adapted to be at least partially heated by a heating device (150).

Abstract: A method for controlling an interaction between droplet targets and a high power and high-repetition-rate laser beam at a laser focus position of the laser beam including providing a droplet generator for generating a train of droplets as a droplet target with a predetermined droplet frequency and velocity in a predetermined direction; providing a high power, high-repetition-rate laser for emitting a pulsed laser beam, which is focused in the laser focus position; aligning the droplet generator such that the train of droplets runs through the laser focus position; generating a train of droplets as a droplet target; and emitting a pulsed laser beam in synchronization with the train of droplets, such that the droplet target interacts with the pulsed laser beam at the laser focus position.

Abstract: The invention relates to a droplet dispensing device (4) comprising a reservoir (9) for containing a liquid medium (10), an outlet (11) for dispensing droplets of said liquid medium (10) from said reservoir (9), an actuation means (12) for generating and transmitting a mechanical oscillation at an excitation frequency, and a resonant structure comprising a piston (15) coupled to said actuation means (12) for transmitting said mechanical oscillation to the liquid medium (10) contained in said reservoir (9) such that droplets are formed from said liquid medium (10), wherein a resonance frequency of said resonant structure is sufficiently close to said excitation frequency, such that resonance occurs. The invention further relates to a UV or X-ray light source, comprising a droplet dispensing device (4) according to the invention, and a method for providing a stream, in particular a monodisperse stream, of droplets by means of the droplet dispensing device (4).

Abstract: A droplet dispensing device includes a reservoir for receiving a liquid material, an outlet nozzle in fluid communication with the reservoir and a piezoelectric actuating means acting on the liquid material at the outlet nozzle to exit the outlet nozzle in a sequence of droplets. A piezoelectric actuating means that includes a piston, which is actuated by a piezoelectric actuator at one end and dips the other, free end into the liquid material is provided just upstream of the outlet nozzle.

Abstract: A method for controlling an interaction between droplet targets and a high power and high-repetition-rate laser beam at a laser focus position of the laser beam including providing a droplet generator for generating a train of droplets as a droplet target with a predetermined droplet frequency and velocity in a predetermined direction; providing a high power, high-repetition-rate laser for emitting a pulsed laser beam, which is focused in the laser focus position; aligning the droplet generator such that the train of droplets runs through the laser focus position; generating a train of droplets as a droplet target; and emitting a pulsed laser beam in synchronization with the train of droplets, such that the droplet target interacts with the pulsed laser beam at the laser focus position

Abstract: A droplet dispensing device includes a reservoir for receiving a liquid material, an outlet nozzle in fluid communication with the reservoir and a piezoelectric actuating means acting on the liquid material at the outlet nozzle to exit the outlet nozzle in a sequence of droplets. A piezoelectric actuating means that includes a piston, which is actuated by a piezoelectric actuator at one end and dips the other, free end into the liquid material is provided just upstream of the outlet nozzle.

Abstract: The extreme ultraviolet light source comprises a production site capable of producing extreme ultraviolet radiation in a laser-produced plasma (3), and a collector optics (6) for collimating the extreme ultraviolet radiation. A pressurized influx of gas forms a gas curtain between the production site and the collector optics (6) in order to protect the collector optics (6) from debris (4) generated at the production site. The gas influx is directed in a way that it follows the surface of the collector optics (6). By thus shielding the collector optics (6) from the debris (4) its lifetime is enhanced. The shielding gas can further be used for cooling the collector optics (6).