A fuel droplet nozzle assembly comprises a first hollow body and a piezoelectric element. The first hollow body comprises an inlet and an outlet and a bore extending between the inlet and the outlet. In use, fuel (for example liquid tin) may be provided into the first hollow body via the inlet under pressure. The piezoelectric element surrounds and is in direct or indirect contact with the first hollow body. In use, the piezoelectric element may be configured to squeeze the first hollow body at an excitation frequency and can be used to generate sound waves in the first hollow body. The fuel droplet nozzle assembly may further comprise a second hollow body surrounding and in direct or indirect contact with the piezoelectric element. Additionally or alternatively, the first hollow body may be a composite body formed from at least: an outer support portion formed from metal; and an inner portion formed from a glass material.

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.

A target supply device is configured to supply a liquid state target substance including tin to a concentration position of laser light to generate EUV light. The target supply device includes a tank configured to contain the target substance; and a nozzle communicating with an inside of the tank, and having a nozzle hole through which the target substance passes. Here, an uneven structure is formed on a surface of the nozzle provided with the nozzle hole and facing the concentration position and exhibits tin repellency larger than tin repellency exhibited by a material of the surface.

A photolithographic apparatus includes a droplet generator, a droplet generator maintenance system, and a controller communicating with the droplet generator maintenance system. The droplet generator maintenance system operatively communicates with the droplet generator, a coolant distribution unit, a gas supply unit, and a supporting member. The gas supply unit includes a heat exchange assembly and an air heating assembly. The coolant distribution unit is configured to control the temperature of the droplet generator within the acceptable droplet generator range.

A freeze valve includes: a valve sleeve defining an axial bore that is in fluid communication with a first fluid port; and a valve body defining an axial opening between an axially-closed end that is received within the axial bore and an axially-open end that is in fluid communication with a second fluid port. The valve body includes one or more through holes formed in a longitudinal section of the valve body at the axially-closed end, each through hole fluidly coupling the axial opening and the axial bore of the valve sleeve.

A nozzle is provided for a droplet generator for a laser-produced plasma radiation source. The nozzle comprises a glass capillary for emitting droplets and a nozzle fitting comprising a throughbore, wherein the glass capillary is at least partially disposed in the throughbore. The nozzle further comprises a glass ferrule coupling the glass capillary to the nozzle fitting, the glass ferrule being conformed to a shape of the throughbore of the nozzle fitting. A method of manufacturing a nozzle for a droplet generator is also provided.

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.

A fluid dispensing system including a fluid-permeable surface having a pre-defined permeability to allow permeation of a fluid, and a controller configured to control the rate of permeation of the fluid into a volume by controlling one or both of a pressure of the fluid and an exposed surface area of the fluid-permeable surface. Also provided is a method of controlling the dispensing of a fluid, a plasma-generating apparatus including such a fluid dispensing system as well as the use of such a system, method, or apparatus in a lithographic apparatus or process.

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.

A droplet generator may form a stable chain of droplets. The droplet generator may enhance the stability of the chain of droplets using a nozzle, a multi-stage skimmer, and/or gas-distribution ring. The nozzle may include a nozzle orifice and filter which may control a target-material flow forming a jet and subsequently coalescing into droplets. The skimmer may include apertures and/or capillaries which are arranged axially along the path of the chain of droplets to skim off a flow of ambient gas. The gas-distribution ring may include a set of holes for even gas distribution, improving the flow of ambient gas within an intermediate chamber. The droplet generator may also include gas, electrical, pressure-sensor, and/or temperature-sensor interfaces. The droplet generator may also include clamps to connect the intermediate chamber with the nozzle and skimmer.