Abstract: A spectral feature selection apparatus includes a dispersive optical element arranged to interact with a pulsed light beam; three or more refractive optical elements arranged in a path of the pulsed light beam between the dispersive optical element and a pulsed optical source; and one or more actuation systems, each actuation system associated with a refractive optical element and configured to rotate the associated refractive optical element to thereby adjust a spectral feature of the pulsed light beam. At least one of the actuation systems is a rapid actuation system that includes a rapid actuator configured to rotate its associated refractive optical element about a rotation axis. The rapid actuator includes a rotary stepper motor having a rotation shaft that rotates about a shaft axis that is parallel with the rotation axis of the associated refractive optical element.

Abstract: Enhancing target features of a pattern imaged onto a substrate. This may include adding one or more assist features to a patterning device pattern in one or more locations adjacent to one or more target features in the patterning device pattern. The one or more assist features are added based on two or more different focus positions in the substrate. This can also include shifting the patterning device pattern and/or a design layout based on the two or more different focus positions and the one or more added assist features. This may be useful for improving across slit asymmetry. Adding the one or more assist features to the pattern and shifting the pattern and/or the design layout enhances the target features by reducing a shift caused by across slit asymmetry for a slit of a multifocal lithographic imaging apparatus. This may reduce the shift across an entire imaging field.

Abstract: A method includes driving, while producing a burst of pulses at a pulse repetition rate, a spectral feature adjuster among a set of discrete states at a frequency correlated with the pulse repetition rate; and in between the production of the bursts of pulses (while no pulses are being produced), driving the spectral feature adjuster according to a driving signal defined by a set of parameters. Each discrete state corresponds to a discrete value of a spectral feature. The method includes ensuring that the spectral feature adjuster is in one of the discrete states that corresponds to a discrete value of the spectral feature of the amplified light beam when a pulse in the next burst is produced by adjusting one or more of: an instruction to the lithography exposure apparatus, the driving signal to the spectral feature adjuster, and/or the instruction to the optical source.

Abstract: A set of the pulses of light in a light beam is passed through a mask toward a wafer during a single exposure pass; at least a first aerial image and a second aerial image on the wafer based on pulses of light in the set of pulses that pass through the mask is generated during a single exposure pass, the first aerial image is at a first plane on the wafer and the second aerial image is at a second plane on the wafer, the first plane and the second plane being spatially distinct from each other and separated from each other by a separation distance along the direction of propagation; and a three-dimensional semiconductor component is formed.

Abstract: Disclosed is a laser discharge chamber in which useful lifetime is extended by local electrical tuning using one or a combination of design of the chamber internal geometry, placement and distribution of components within the chamber such as electrodes, current returns, and capacitors, and selective electrical isolation of portions of the components.

Abstract: Systems, methods, and computer programs for increasing a contrast for a lithography system are disclosed. In one aspect, a method of optimizing a process for imaging a feature on a substrate using a photolithography system is disclosed, the method including obtaining an optical spectrum of a light beam for the imaging, wherein the light beam includes pulses having a plurality of different wavelengths, and narrowing the optical spectrum of the pulses of the light beam for the imaging to improve a quality metric of the imaging.

Abstract: Systems, methods, and computer programs for increasing a depth of focus for a lithography system are disclosed. In one aspect, a method includes providing an optical spectrum, a mask pattern, and a pupil design, that together are configured to provide the lithography system with a depth of focus. The method also includes iteratively varying the optical spectrum and an assist feature in the mask pattern to provide a modified optical spectrum and a modified mask pattern that increases the depth of focus. The method further includes configuring a component of the lithography system based on the modified optical spectrum and the modified mask pattern that increases the depth of focus.

Abstract: A discharge chamber for a deep ultraviolet (DUV) light source includes a housing; and a first electrode and a second electrode in the housing, the first electrode and the second electrode being separated from each other to form a discharge region between the first electrode and the second electrode, the discharge region being configured to receive a gain medium including at least one noble gas and a halogen gas. At least one of the first electrode and the second electrode includes a metal alloy including more than 33% and less than 50% zinc by weight.

Abstract: Methods and apparatuses for aligning and diagnosing the laser beam traversing an optical train in a highly space-efficient, lower cost and/or retrofit-friendly manner are disclosed. The optical components of the optical train are mounted such that one or more optical components can direct their exit laser beam to partially or wholly scan across one or more downstream sensors. Correlation data between physical disposition of optical components and the points of impact data and/or beam quality data are employed to, among others, align and/or diagnose the laser beam and/or localize failure sites and/or optimize maintenance schedule.

Abstract: A laser system's laser light energy control and resulting dose control is improved by creating and using a set of gain estimators, one for each of a set or range of laser light pulse repetition rates. When a new repetition rate is used, its corresponding gain estimator is retrieved, used to compute the voltage to fire the laser source, and updated. The resulting generated laser light thereby avoids the convergence delay inherent in prior laser systems and, further, can repeatedly do so with subsequent specified repetition rates.

Abstract: A method includes: producing a light beam made up of pulses having a wavelength in the deep ultraviolet range, each pulse having a first temporal coherence defined by a first temporal coherence length and each pulse being defined by a pulse duration; for one or more pulses, modulating the optical phase over the pulse duration of the pulse to produce a modified pulse having a second temporal coherence defined by a second temporal coherence length that is less than the first temporal coherence length of the pulse; forming a light beam of pulses at least from the modified pulses; and directing the formed light beam of pulses toward a substrate within a lithography exposure apparatus.

Abstract: Online calibration of laser performance as a function of the repetition rate at which the laser is operated is disclosed. The calibration can be periodic and carried out during a scheduled during a non-exposure period. Various criteria can be used to automatically select the repetition rates that result in reliable in-spec performance. The reliable values of repetition rates are then made available to the scanner as allowed values and the laser/scanner system is then permitted to use those allowed repetition rates.

Abstract: In a method, energy is supplied to a first gas discharge chamber of a first stage until a pulsed amplified light beam is output from the first stage and directed toward a second stage. While the energy is supplied to the first gas discharge chamber: a value of an operating parameter of the first gas discharge chamber is measured; it is determined whether to adjust an operating characteristic of the first gas discharge chamber based on the measured value; and, the operating characteristic of the first gas discharge chamber is adjusted if it is determined that the operating characteristic of the first gas discharge chamber should be adjusted. After it is determined that the operating characteristic of the first gas discharge chamber no longer should be adjusted, then an adjustment procedure is applied to an operating characteristic of a second gas discharge chamber of the second stage.

Abstract: Disclosed is an apparatus for and method of measuring the concentration of F2 in the laser gas used in an excimer laser. Quartz Enhanced Photoacoustic Spectroscopy is used to obtain a direct measurement of F2 concentration quickly and using only a small sample volume.

Abstract: Methods and apparatus for processing an image of a beam generated by an optical system to extract information indicative of an extent of damage to optical elements in the optical system. Also disclosed is a beam image and analysis tool capable of acquiring an image of a beam at any one of a number of locations.

Abstract: A spectral feature selection apparatus includes a dispersive optical element arranged to interact with a pulsed light beam; three or more refractive optical elements arranged in a path of the pulsed light beam between the dispersive optical element and a pulsed optical source; and one or more actuation systems, each actuation system associated with a refractive optical element and configured to rotate the associated refractive optical element to thereby adjust a spectral feature of the pulsed light beam. At least one of the actuation systems is a rapid actuation system that includes a rapid actuator configured to rotate its associated refractive optical element about a rotation axis. The rapid actuator includes a rotary stepper motor having a rotation shaft that rotates about a shaft axis that is parallel with the rotation axis of the associated refractive optical element.

Abstract: Methods and apparatus for controlling laser firing timing and hence bandwidth in a laser capable of operating at any one of multiple repetition rates.

Abstract: A wavelength error for each pulse in a first subset of pulses emitted from an optical source is determined, the wavelength error being the difference between a wavelength for a particular pulse and a target wavelength; a pulse-by-pulse correction signal is determined based on the determined wavelength error, the pulse-by-pulse correction signal including a correction signal associated with each pulse in the first subset of pulses; and a correction based on the determined pulse-by-pulse correction signal is applied to each pulse in a second subset of pulses emitted from the optical source, where applying a correction to a pulse in the second subset of pulses reduces the wavelength error of the pulse in the second subset of pulses.

Abstract: Online calibration of laser performance as a function of the repetition rate at which the laser is operated is disclosed. The calibration can be periodic and carried out during a scheduled during a non-exposure period. Various criteria can be used to automatically select the repetition rates that result in reliable in-spec performance. The reliable values of repetition rates are then made available to the scanner as allowed values and the laser/scanner system is then permitted to use those allowed repetition rates.

Abstract: A method of controlling output of a radiation source, the method including: periodically monitoring an output energy of the radiation source; determining a difference between a reference energy signal and the monitored output energy; determining a feedback value; determining a desired output energy of the radiation source for a subsequent time period; and controlling an input parameter of the radiation source in dependence on the determined desired output energy during the subsequent time period. If the magnitude of the determined difference between the monitored output energy of the radiation source and the reference energy signal exceeds a threshold value: the determined difference does not contribute to the feedback value; and the determined difference is spread over the subsequent time period according to a reference energy signal adjustment profile and the reference energy signal adjustment profile is added to the reference energy signal for the subsequent time period.