Cymer, Inc.

The Boeing Company

Asml Netherlands B.v.

Kevin M O'Brien

Joshua Jon Thornes

Jonathan A Tekawy

Herman Philip Godfried

Tanuj Aggarwal

Frank Everts

Russell Allen Burdt

Michael De La Chapelle

Robert N Jacques

Thomas Patrick Duffey

William Joseph Purpura

Daniel Jason Riggs

Michael Anthony Borrello

Rahul Ahlawat

Rui Jiang

Herve A Besaucele

Matthew Graham

Rostislav Rokitski

Wilhelmus Patrick Elisabeth Maria Op 't Root

Fedor Trintchouk

Wayne J Dunstan

Andrei Dorobantu

Yingbo Zhao

Nakgeuon Seong

Aravind Ratnam

Leon Pieter Paul Saanen

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.

Spectral feature selection and pulse timing control of a pulsed light beam

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.

Laser light energy and dose control using repetition rate based gain estimators

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.

Online calibration for repetition rate dependent performance variables

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.

Lithographic apparatus and method

An optical lithography system is monitored. Information is received from the optical lithography system; a rule is accessed, the rule being associated with one or more of an event in the optical lithography system and an amount of time; a module stored in a library of modules is identified based on the accessed rule; whether a particular condition exists in the optical lithography system is determined using the identified module and the information received from the optical lithography system; and if the particular condition exists, a command signal is generated based on one or more characteristics of the particular condition and provided to an optical source of the optical lithography system. The command signal is based on the determined particular condition, and the command signal is sufficient to change one or more operating parameters of the optical source.

Monitoring system for an optical lithography system

A system and method for automatically performing gas optimization after a refill in the chambers of a two chamber gas discharge laser is disclosed. The laser is fired at low power, and the gas in the amplifier laser chamber bled if necessary until the discharge voltage meets or exceeds a minimum value without dropping the pressure below a minimum value. The power output is increased to a burst pattern that approximates the expected operation of the laser, and the amplifier chamber gas bled again if necessary until the voltage and an output energy meet or exceed minimum values, or until the pressure is less than a minimum value. The gas in the master oscillator chamber is then bled if necessary until the output energy of the master oscillator meets or falls below a maximum value, again without dropping the pressure in the chamber below the minimum value. While the pressure is adjusted, bandwidth is also measured and adjusted to stay within a desired range. Once the target values are provided, the process runs quickly without manual interaction.

System and method for automatic gas optimization in a two-chamber gas discharge laser system

A system includes a first actuation module coupled to a first actuatable apparatus of an optical source, the first actuatable apparatus being altered by the first actuation module to adjust the spectral feature of the pulsed light beam; a second actuation module coupled to a second actuatable apparatus of the optical source, the second actuatable apparatus being altered by the second actuation module to adjust the spectral feature of the pulsed light beam; and a control system configured to receive an indication regarding the operating state of the first actuatable apparatus; and send a signal to the second actuation module to adjust the spectral feature of the pulsed light beam to either: prevent the first actuatable apparatus from saturating based on the operating state of the first actuatable apparatus, or desaturate the first actuatable apparatus if the first actuatable apparatus is saturated.

Pulsed light beam spectral feature control

A system includes a first actuatable apparatus of an optical source, the first actuatable apparatus being altered within a range of values about a target value to thereby alter a spectral feature of the light beam; a second actuatable apparatus of the optical source, the second actuatable apparatus being altered to thereby alter the spectral feature of the light beam; a metrology system including an observation system configured to output an indication of a deviation between the actual value at which the first actuatable apparatus is operating and the target value; and a control system configured to determine whether the deviation is greater than an acceptable deviation, and, if it is greater than the acceptable deviation, then send a signal to a second actuation module controlling the second actuatable apparatus to adjust the actual value at which the first actuatable apparatus is operating to be closer to the target value.

A spectral feature of a pulsed light beam produced by an optical source is estimated by modifying the wavelength of the pulsed light beam based on a predefined repeating pattern having a pattern period including a plurality of steps, the modification including shifting the wavelength of the pulsed light beam by a wavelength offset from a baseline wavelength for each step in the pattern period; measuring the wavelength of the light beam for each step in the pattern period as the wavelength is modified across the pattern; and estimating a spectral feature of the pulsed light beam over an evaluation window that includes all of the steps within the pattern period based at least in part on the measured wavelength of the light beam for each step in the pattern period.

Active spectral control during spectrum synthesis

Systems and methods for automatically performing a high accuracy gas refill in a laser chamber of a two chamber gas discharge laser such as an excimer laser are disclosed. Based upon a target pressure and halogen concentration that is either predetermined or entered by a user, and with no further user action, a non-halogen containing gas is added to the chamber to a first pressure, followed by the addition of halogen containing gas to a second pressure which is greater than a target pressure for the chamber, such that the halogen content in the gas at the second pressure is at a desired concentration. The gas in the chamber is bled until the pressure drops to the target pressure. The amount of non-halogen containing gas added is estimated automatically, and the amount of halogen containing gas is measured so that the desired concentration is obtained, taking into account both temperature and any gas remaining in the fill pipes from prior laser operation.

System and method for high accuracy gas refill in a two chamber gas discharge laser system

An apparatus includes a light source that produces a light beam, a bandwidth measurement system, a plurality of bandwidth actuation systems, and a control system. Each bandwidth actuation system includes one or more bandwidth actuators and each bandwidth actuation system is connected to an optical feature that is optically coupled to the produced light beam and operable to modify the connected optical feature to select a bandwidth within a bandwidth range of the produced light beam. The control system is connected to the bandwidth measurement system and to the plurality of bandwidth actuation systems. The control system is configured to switch between activating and operating a first bandwidth actuation system and activating and operating a second bandwidth actuation system independently and separately of activating and operating the first bandwidth actuation system based on a provided bandwidth measurement and a selected target bandwidth.

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Los Alamitos, CA, United States of America

Kevin M O'Brien