Cymer, Inc.

John A Rule

Robert N Jacques

Jacob P Lipcon

Alexander Igorevich Ershov

Toshihiko Ishihara

William N Partlo

Richard M Ness

Paul C Melcher

John P Fallon

John Meisner

Igor Vladimirovich Fomenkov

Richard L Sandstrom

John Martin Algots

Ronald L Spangler

Ivan Lalovic

Paolo Zambon

Tom A Watson

David J Warkentin

Fedor Trintchouk

Baruch Pletner

Frederick A Palenschat

James A Carmichael

Leonard Lublin

Omez S Mesina

Weijie Zheng

Richard C Morton

Vladimir V Fleurov

The present invention provides a control system for a modular high repetition rate two discharge chamber ultraviolet gas discharge laser. In preferred embodiments, the laser is a production line machine with a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. Feedback timing control techniques are provided for controlling the relative timing of the discharges in the two chambers with an accuracy in the range of about 2 to 5 billionths of a second even in burst mode operation. This MOPA system is capable of output pulse energies approximately double the comparable single chamber laser system with greatly improved beam quality.

Control system for a two chamber gas discharge laser system

The present invention provides a control system for a modular high repetition rate two discharge chamber ultraviolet gas discharge laser. In preferred embodiments, the laser is a production line machine with a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. Novel control features specially adapted for a two-chamber gas discharge laser system include: (1) pulse energy controls, with nanosecond timing precision (2) precision pulse to pulse wavelength controls with high speed and extreme speed wavelength tuning (3) fast response gas temperature control and (4) Finjection controls with novel learning algorithm.

Control system for a two chamber gas discharge laser

An integrated circuit lithography technique called spectral engineering by Applicants, for bandwidth control of an electric discharge laser. In a preferred process, a computer model is used to model lithographic parameters to determine a desired laser spectrum needed to produce a desired lithographic result. A fast responding tuning mechanism is then used to adjust center wavelength of laser pulses in a burst of pulses to achieve an integrated spectrum for the burst of pulses approximating the desired laser spectrum. The laser beam bandwidth is controlled to produce an effective beam spectrum having at least two spectral peaks in order to produce improved pattern resolution in photo resist film. Line narrowing equipment is provided having at least one piezoelectric drive and a fast bandwidth detection control system having a time response of less than about 2.0 millisecond. In a preferred embodiment, a wavelength tuning mirror is dithered at dither rates of more than 500 dithers per second in phase with the repetition rate of the laser. In one case, the piezoelectric drive was driven with a square wave signal and in a second case it was driven with a sine wave signal. In another embodiment, the maximum displacement was matched on a one-to-one basis with the laser pulses in order to produce a desired average spectrum with two peaks for a series of laser pulses. Other preferred embodiments utilize three separate wavelength tuning positions producing a spectrum with three separate peaks.

Laser spectral engineering for lithographic process

The present invention relates to a fluorine gas discharge laser system and control of replenishment of fluorine gas as the gas discharge laser operates and consumes fluorine.

Method and apparatus for controlling the output of a gas discharge laser system

A method and apparatus are disclosed for controlling the output of a two chamber gas discharge laser comprising an oscillator gas discharge laser and an amplifier gas discharge laser that may comprise establishing a multidimensional variable state space comprising a coordinate system having at least two coordinates, each coordinate comprising a selected variable representing an operating parameter of the oscillator or the amplifier; tracking a multidimensional operating point in the multidimensional variable state space according to the variation of the selected variables in either or both of the oscillator or the amplifier to determine the position of the multidimensional operating point in the multidimensional state space; determining from the position of the multidimensional operating point in the multidimensional operating space a region from a plurality of defined regions in the multidimensional operating space in which the multidimensional operating point is located and identifying the region.

Method and apparatus for controlling the output of a gas discharge MOPA laser system

An automatic Flaser gas control, for a modular high repetition rate ultraviolet gas discharge laser. The laser gas control includes techniques, monitors, and processor for monitoring the Fconsumption rates through the operating life of the laser system. These consumption rates are used by a processor programmed with an algorithm to determine Finjections needed to maintain laser beam quality within a delivery range. Preferred embodiments include Fcontrols for a two-chamber MOPA laser system.

Automatic gas control system for a gas discharge laser

An electric discharge laser with fast wavelength correction. Fast wavelength correction equipment includes at least one piezoelectric drive and a fast wavelength measurement system and fast feedback response times. In a preferred embodiment, equipment is provided to control wavelength on a slow time frame of several milliseconds, on a intermediate time from of about one to five milliseconds and on a very fast time frame of a few microseconds. Preferred techniques include a combination of a relatively slow stepper motor and a very fast piezoelectric driver for tuning the laser wavelength using a tuning mirror. A preferred control technique is described (utilizing a very fast wavelength monitor) to provide the slow and intermediate wavelength control with the combination of a stepper motor and a piezoelectric driver. Very fast wavelength control is provided with a piezoelectric load cell in combination with the piezoelectric driver. Preferred embodiments provide (1) fast feedback control based on wavelength measurements, (2) fast vibration control, (3) active damping using the load cell and an active damping module, (4) transient inversion using feed forward algorithms based on historical burst data. A preferred embodiment adapts the feed forward algorithms to current conditions. Another preferred embodiment measures tuning mirror position to permit wavelength pretuning and active wavelength tuning.

Laser wavelength control unit with piezoelectric driver

A system that provides a base stabilization system for controlling motion of a controlled structure. The system includes a ground structure such as the floor of a fabrication facility and the controlled structure includes a base on which equipment is mounted. The system also includes at least three air mounts and a plurality of actuators all attached to the ground structure and to the base to isolate the base from the ground structure and to stabilize the base. The system includes a plurality of position and acceleration sensors each of which are co-located with a corresponding actuator. The system also includes a multi-input, multi output feedback control system comprising a computer processor programmed with a feedback control algorithm for controlling each of the actuators based on feedback signals from each of the sensors. The co-location of the sensors with the actuators avoids serious problems resulting from higher order vibration modes.

Base stabilization system

Growing community of inventors

Hingham, MA, United States of America

John A Rule