37 results about "Line narrowing" patented technology

An injection seeded modular gas discharge laser system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 mJ or greater. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. The chambers can be controlled separately permitting separate optimization of wavelength parameters in the master oscillator and optimization of pulse energy parameters in the amplifying chamber. A preferred embodiment in an ArF excimer laser system configured as a MOPA and specifically designed for use as a light source for integrated circuit lithography. In the preferred MOPA embodiment, each chamber comprises a single tangential fan providing sufficient gas flow to permit operation at pulse rates of 4000 Hz or greater by clearing debris from the discharge region in less time than the approximately 0.25 milliseconds between pulses. The master oscillator is equipped with a line narrowing package having a very fast tuning mirror capable of controlling centerline wavelength on a pulse-to-pulse basis at repetition rates of 4000 Hz or greater to a precision of less than 0.2 pm.

A line narrowing method and module for a narrow band DUV high power high repetition rate gas discharge laser producing output laser light pulse beam pulses in bursts of pulses, the module having a nominal optical path are disclosed which may comprise: a dispersive center wavelength selection optic moveably mounted within an optical path of the line narrowing module, selecting at least one center wavelength for each pulse determined at least in part by the angle of incidence of the laser light pulse beam containing the respective pulse on the dispersive wavelength selection optic; a first tuning mechanism operative in part to select the angle of incidence of the laser light pulse beam containing the respective pulse upon the dispersive center wavelength selection optic, by selecting an angle of transmission of the laser light pulse beam containing the pulse toward the dispersive center wavelength selection optic; a second tuning mechanism operative in part to select the angle of incidence of the laser light pulse beam containing the respective pulse by changing the position of the dispersive center wavelength selection optic relative to the nominal optical path of the line narrowing module; wherein the second tuning mechanism coarsely selects a value for the center wavelength and the first tuning mechanism more finely selects the value for the center wavelength. The apparatus and method may further comprise at least one beam expanding and redirecting prism in the optical path of the line narrowing module; the first tuning mechanism selecting an angle of incidence of the at least a first spatially defined portion of the laser light pulse beam by changing the position of the at least one beam expanding prism relative to the nominal optical path of the line narrowing module. The first and second tuning mechanisms may be controlled by a center wavelength controller during a burst based upon feedback from a center wavelength detector detecting the center wavelength of at least one other pulse in the burst of pulses and the controller providing the feedback based upon an algorithm employing the detected center wavelength for the at least one other pulse in the burst. The first tuning mechanism may comprise an electro-mechanical course positioning mechanism and a fine positioning mechanism comprising an actuatable material that changes position or shape when actuated.

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.

A method and apparatus is disclosed for operating a laser output light beam pulse line narrowing mechanism that may comprise a nominal center wavelength and bandwidth selection optic; a static wavefront compensation mechanism shaping the curvature of the selection optic; an active wavefront compensation mechanism shaping the curvature of the selection optic and operating independently of the static wavefront compensation mechanism. The method and apparatus may comprise the nominal center wavelength and bandwidth selection optic comprises a grating; the static wavefront compensation mechanism applies a pre-selected bending moment to the grating; the active wavefront compensation mechanism applies a separate selected bending moment to the grating responsive to the control of a bending moment controller based on bandwidth feedback from a bandwidth monitor monitoring the bandwidth of the laser output light beam pulses. The active wavefront compensation mechanism may comprise a pneumatic drive mechanism.

The present invention relates to precision linewidth control and frequency measurements of continuous wave lasers for the near to far IR spectral regions, precision frequency synthesizers and exemplary applications in molecular detection. Methods and systems are disclosed for simultaneous line narrowing of cw lasers, as well as referencing the desired emission wavelength to a frequency comb laser.

An excimer laser and a line-narrowing module capable of increasing and maximizing production yield in semiconductor manufacturing are disclosed. The line-narrowing module utilizes a beam expander that passes laser light, produced by and incident from a generator of the excimer laser and collimates the laser light in one direction. A diffraction grating receives the collimated laser light and diffracts the laser light and causes a traveling direction of the laser light to be separated according to an associated wavelength of the laser light. A multi-wavelength reflector located at a reflecting position on one side between the diffraction grating and the beam expander in order to re-enter the laser light having a multi-wavelength into the generator through the beam expander. The multi-wavelength reflector reflects the laser light consisting of a plurality of wavelengths among the laser light whose traveling direction is separated from the diffraction grating onto the beam expander.

A grating for line-narrowing a laser beam that is outputted from a laser apparatus at a wavelength in a vacuum ultraviolet region may include: a grating substrate; a first aluminum metal film formed above the grating substrate, the first aluminum metal film having grooves in a surface thereof; and a first protective film formed by an ALD method above the first aluminum metal film.