Abstract: A method for monitoring a shock wave in an extreme ultraviolet light source includes irradiating a target droplet in the extreme ultraviolet light source apparatus of an extreme ultraviolet lithography tool with ionizing radiation to generate a plasma and to detect a shock wave generated by the plasma. One or more operating parameters of the extreme ultraviolet light source is adjusted based on the detected shock wave.

Abstract: A control system includes a plurality of pressure sensors, each to detect a pressure in a respective dynamic gas lock (DGL) nozzle control region of a plurality of DGL nozzle control regions. Each DGL nozzle control region includes one or more DGL nozzles. The control system includes a plurality of mass flow controllers (MFCs). Each MFC of the plurality of MFCs is to control a flow velocity in a respective DGL nozzle control region of the plurality of DGL nozzle control regions. The control system includes a controller to selectively cause one or more MFCs of the plurality of MFCs to adjust flow velocities in one or more DGL nozzle control regions of the plurality of DGL nozzle control regions based on pressures detected by the plurality of pressure sensors in DGL nozzle control regions of the plurality of DGL nozzle control regions.

Abstract: A light source for EUV radiation is provided. The light source includes a target droplet generator, a laser generator, and a controller. The target droplet generator is configured to provide target droplets to a source vessel. The laser generator is configured to provide a plurality of first laser pulses according to a control signal to irradiate the target droplets in the source vessel to generate plasma as the EUV radiation. The controller is configured to provide the control signal according to the temperature of the source vessel and droplet positions of the target droplets. When the temperature of the source vessel exceeds a temperature threshold value and a standard deviation of the droplet positions of the target droplets exceeds a first standard deviation threshold value, the controller is configured to provide the control signal to the laser generator, so as to stop providing the first laser pulses.

Abstract: An apparatus for generating extreme ultraviolet (EUV) radiation includes a droplet generator configured to generate target droplets. An excitation laser is configured to heat the target droplets using excitation pulses to convert the target droplets to plasma. An energy detector is configured to measure a variation in EUV energy generated when the target droplets are converted to plasma. A feedback controller is configured to adjust parameters of the droplet generator and/or the excitation laser based on the variation in EUV energy.

Abstract: A reticle, a reticle container and a method of lithography process are provided. The reticle container includes: a cover configured to protect a reticle, a baseplate, and a discharging device on the baseplate. The baseplate has: a top surface configured to engage to the cover and a bottom surface opposite to the top surface. The discharging device is configured to neutralize static charges accumulated on the reticle.

Abstract: A method and system for generating EUV light includes providing a laser beam having a Gaussian distribution. This laser beam can be then modified from a Gaussian distribution to a ring-like distribution. The modified laser beam is provided through an aperture in a collector and interfaces with a moving droplet target, which generates an extreme ultraviolet (EUV) wavelength light. The generated EUV wavelength light is provided to the collector away from the aperture. In some embodiments, a mask element may also be used to modify the laser beam to a shape.

Abstract: Methods of fabricating and using an overlay mark are provided. In some embodiments, the overlay mark includes an upper layer and a lower layer disposed below the upper layer. The lower layer includes a first plurality of compound gratings extending in a first direction and disposed in a first region of the overlay mark, each of the first plurality of compound gratings including one first element and at least two second elements disposed on one side of the first element, and a second plurality of compound gratings extending the first direction and disposed in a second region of the overlay mark, each of the second plurality of compound gratings including one third element and at least two fourth elements on one side of the third element. The first plurality of compound gratings is a mirror image of the second plurality of compound gratings.

Abstract: A method for a lithography exposure process is provided. The method includes irradiating a target droplet with a laser beam to create an extreme ultraviolet (EUV) light. The method further includes reflecting the EUV light with a collector. The method also includes discharging a cleaning gas over the collector through a gas distributor positioned next to the collector. A portion of the cleaning gas is converted to free radicals before the cleaning gas leaves the gas distributor, and the free radicals are discharged over the collector along with the cleaning gas.

Abstract: An extreme ultra violet (EUV) radiation source apparatus includes a collector, a target droplet generator for generating a tin (Sn) droplet, a rotatable debris collection device and a chamber enclosing at least the collector and the rotatable debris collection device. The rotatable debris collection device includes a first end support, a second end support and a plurality of vanes, ends of which are supported by the first end support and the second end support, respectively. A surface of at least one of the plurality of vanes is coated by a catalytic layer, which reduces a SnH4 to Sn.

Abstract: A light source for EUV is provided. The light source includes a target droplet generator, a laser generator, and a controller. The target droplet generator is configured to provide target droplets to a source vessel. The laser generator is configured to provide first laser pulses according to a control signal to irradiate the target droplets in the source vessel. The controller is configured to provide the control signal according to at least two of process parameters including temperature of the source vessel, droplet positions of the target droplets, and beam sizes and focal points of the first laser pulses. When the average value or the standard deviation of the temperature of the source vessel and the droplet positions of the target droplets exceed the predetermined range, the controller is configured to provide the control signal to the laser generator to stop providing the first laser pulses.

Abstract: A reticle, a reticle container and a method for discharging static charges accumulated on a reticle are provided. The reticle includes a mask substrate, a reflective multilayer (ML) structure, a capping layer, an absorption structure and a conductive material structure. The mask substrate has a front-side surface and a back-side surface. The reflective ML structure is positioned over the front-side surface of mask substrate. The capping layer is positioned over the reflective ML structure. The absorption structure is positioned over the capping layer. The conductive material structure is positioned over a sidewall surface of the mask substrate and a sidewall surface of the absorption structure.

Abstract: Methods of fabricating and using an overlay mark are provided. In some embodiments, the overlay mark includes an upper layer and a lower layer disposed below the upper layer. The lower layer includes a first plurality of compound gratings extending in a first direction and disposed in a first region of the overlay mark, each of the first plurality of compound gratings including one first element and at least two second elements disposed on one side of the first element, and a second plurality of compound gratings extending the first direction and disposed in a second region of the overlay mark, each of the second plurality of compound gratings including one third element and at least two fourth elements on one side of the third element. The first plurality of compound gratings is a mirror image of the second plurality of compound gratings.

Abstract: A method for a lithography exposure process is provided. The method includes irradiating a target droplet with a laser beam to create an extreme ultraviolet (EUV) light. The method further includes reflecting the EUV light with a collector. The method also includes discharging a cleaning gas over the collector through a gas distributor positioned next to the collector. A portion of the cleaning gas is converted to free radicals before the cleaning gas leaves the gas distributor, and the free radicals are discharged over the collector along with the cleaning gas.

Abstract: An apparatus for generating extreme ultraviolet (EUV) radiation includes a droplet generator configured to generate target droplets. An excitation laser is configured to heat the target droplets using excitation pulses to convert the target droplets to plasma. An energy detector is configured to measure a variation in EUV energy generated when the target droplets are converted to plasma. A feedback controller is configured to adjust parameters of the droplet generator and/or the excitation laser based on the variation in EUV energy.

Abstract: An extreme ultra violet (EUV) radiation source apparatus includes a collector, a target droplet generator for generating a tin (Sn) droplet, a rotatable debris collection device and a chamber enclosing at least the collector and the rotatable debris collection device. The rotatable debris collection device includes a first end support, a second end support and a plurality of vanes, ends of which are supported by the first end support and the second end support, respectively. A surface of at least one of the plurality of vanes is coated by a catalytic layer, which reduces a SnH4 to Sn.

Abstract: A device is disclosed that includes a master controller, a process chamber, a local controller, a switch, and a data storage. The process chamber is configured to generate a data according to a EUV light generation process. The local controller is coupled to the master controller and configured to control the process chamber. The switch is coupled between the master controller and the local controller, wherein the switch is configured to provide paths for the local controller to communicate with the master controller. The data storage directly connected to the local controller and configured to store the data. The local controller communicates directly with the data storage.

Abstract: In some embodiments, a reticle structure is provided. The reticle structure includes a reticle stage and a reticle mounted on the reticle stage. The reticle stage includes plural first burls and plural second burls, in which the second burls are disposed on a center of the reticle stage and the first burls disposed on an edge of the reticle stage such that the first burls surround the second burls. The reticle includes a base material and a pattern layer overlying the base material. The base material is secured on the first and second burls of the reticle stage. The pattern layer includes plural first gratings, and each of the first burls is vertically aligned with one of the first gratings.

Abstract: A method for extreme ultraviolet (EUV) lithography includes loading an EUV mask to a lithography system; loading a wafer to the lithography system, wherein the wafer includes a resist layer sensitive to EUV radiation; producing EUV radiation by heating target plumes using a radiation source; and exposing the resist layer to the EUV radiation while monitoring a speed of the target plumes.

Abstract: An extreme ultra-violet (EUV) lithography system includes an EUV source and EUV scanner. A droplet generator provides a droplet stream in the EUV source. A gas shield is configured to surround the droplet stream. When a laser reacts a droplet in the stream EUV radiation and ionized particles are produced. The gas shield can reduce contamination resulting from the ionized particles by conveying the ionized particles to a droplet catcher. Components of the EUV source may be biased with a voltage to repel or attract ionized particles to reduce contamination from the ionized particles.

Abstract: A method of controlling a feedback system with a data matching module of an extreme ultraviolet (EUV) radiation source is disclosed. The method includes obtaining a slit integrated energy (SLIE) sensor data and diffractive optical elements (DOE) data. The method performs a data match, by the data matching module, of a time difference of the SLIE sensor data and the DOE data to identify a mismatched set of the SLIE sensor data and the DOE data. The method also determines whether the time difference of the SLIE sensor data and the DOE data of the mismatched set is within an acceptable range. Based on the determination, the method automatically validates a configurable data of the mismatched set such that the SLIE sensor data of the mismatched set is valid for a reflectivity calculation.