摘要:
Laser light wavelength control is provided by periodically predicting a next position of a light controlling prism using a model of the prism's motion characteristics. The prediction is then updated if a measurement of laser output wavelength is obtained. However, because the predictions are made without waiting for a measurement, they can be made more frequently than the laser firing repetition rate and the prism can be repositioned at discrete points in time which can occur more frequently than the laser firing events. This also reduces performance degradation which may be caused by being one pulse behind a laser measurement and the resultant laser control signal being applied.
摘要:
A high energy, high repetition rate workpiece surface heating method and apparatus are disclosed which may comprise a pulsed XeF laser operating operating at or above 4000 Hz and producing a laser output light pulse beam at a center wavelength of about 351 nm; an optical system narrowing the laser output light pulse beam to less than 20 [mu]m in a short axis of the laser output light pulse beam and expanding the laser output light pulse beam to form in a long axis of the beam workpiece covering extent of the long axis; the optical system including a field stop intermediate the laser and the workpiece; the workpiece comprising a layer to be heated; ; wherein the optical system focuses the laser output light pulse beam at a field stop with a magnification sufficient to maintain an intensity profile that has sufficiently steep side walls to allow the field stop to maintain a sufficiently steep beam profile at the workpiece without blocking the beam profile at too high an intensity level 2. The apparatus may also have a high average power in the laser output light pulse beam as delivered to the workpiece and a linebow correction mechanism in a short axis optical assembly. The linebow correction mechanism may comprise a plurality of weak cross cylinders. The system may comprise a catadioptric projection system. The line width due to laser diffraction and divergence may be less than geometric limitations.; The system may project adjacent peaks of the nominal XeF spectrum to improve overall depth of focus through the separate center wavelengths of each respective adjacent peak having a different focal plane at the workpiece. The system may comprise a linebow is correction mechanism within a field stop optical assembly correcting linebow at the field stop plane and within a workpiece projection optical assembly correcting linebow at the workpiece plane.
摘要:
[0090} Systems and methods for automatically performing a high accuracy gas inject in a laser chamber of a two chamber gas discharge laser such as an excimer laser are disclosed. A mathematical model, relates the amount of halogen gas in the laser chamber after an inject to the amount of halogen gas present prior to the inject, the amount of halogen gas injected., and the consumption rate of halogen gas in the chamber, A fixed amount of halogen gas is added to the chamber in an initial number of injects to allow transients to settle out, after which the amount of halogen gas to be injected is that calculated to result in a desired amount of halogen gas after the inject according to the model. Measurements are taken after injects to update the actual amount of halogen gas present and the consumption rate of the halogen gas.
摘要:
Systems (and methods therefor) for generating EUV radiation that comprise an arrangement producing a laser beam directed to an irradiation region and a droplet source. The droplet source includes a fluid exiting an orifice and a sub-system having an electro-actuatable element producing a disturbance in the fluid. The electro-actuatable element is driven by a first waveform to produce droplets for irradiation to generate the EUV radiation, the droplets produced by the first waveform having differing initial velocities causing at least some adjacent droplets to coalesce as the droplets travel to the irradiation region, and a second waveform, different from the first waveform, to dislodge contaminants from the orifice.