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The interaction of a Nd:YAG laser, pulse duration of 40 ps, with a titanium nitride (TiN) and tungsten-titanium (W-Ti) thin films deposited at silicon was studied. The peak intensity on targets was up to 10(12) W/cm(2). Results have shown that the TiN surface was modified, by the laser beam, with energy density of GT = 0.18 J/cm(2) (lambda(laser) = 532 nm) as well as of 30.0 J/cm(2) (lambda(laser)= 1064 nm). The W-Ti was surface modified with energy density of 5.0 J/cm(2) (lambda(laser)= 532 nm). ne energy absorbed from the Nd:YAG laser beam is partially converted to thermal energy, which generates a series of effects such as melting, vaporization of molten materials, dissociation and ionization of the vaporized material, appearance of plasma, etc. The following morphological changes of both targets were observed: (i) The appearance of periodic microstructures, in the central zone of the irradiated area, for laser irradiation at 532 nm. Accumulation of great number of laser pulses caused film ablation and silicon modification. (ii) Hole formation on the titanium nitride/silicon target was registered at 1064 nm. The process of the Nd:YAG laser interaction with both targets was accompanied by plasma formation above the target. 3rd International Conference on Superstrong Fields in Plasmas, Sep 19-24, 2005, Varenna, Italy

A two‐element molybdenum‐silicon multilayer monochromator has been tested in the energy range 60–110 eV on a differentially pumped bending magnet beamline having a high‐energy cutoff of 3.5 keV at the Stanford Synchrotron Radiation Laboratory. The multilayer structures were sputter deposited onto 5‐cm‐diam (111) single‐crystal silicon and contained 20 molybdenum layers (4.93 nm thick) separated by amorphous silicon layers (7.8 nm thick). A 1200 l/mm gold transmission grating was used to independently measure the wavelength passed by the monochromator. The Al L2,3 absorption edge jump was also measured using the monochromator. These experimental results are compared to model calculations for both the synchrotron source‐monochromator and the synchrotron source‐monochromator‐Al filter configurations and excellent agreement is shown.

A dedicated X-ray lithography system has been developed on beam line III-4 at the Stanford Synchrotron Radiation Laboratory (SSRL). The research program at SSRL includes studies of the spectral sensitivity of X-ray resists, mask characterization, and the applications of novel X-ray optics. The facilities available for this work and recent results in these areas will be described.

A model for the introduction of noise into computer simulations of FEL pulse propagationJohn M. J. Madey, Stephen V. Benson, Todd I. Smith and Renato RedaelliHigh Energy Physics Laboratory, Stanford University, Stanford, California 94305AbstractWe have developed a model for computer simulation of shot noise and quantum field fluctu-ations in order to study the effect of noise on the startup and saturated operation of afree electron laser. The model is described and some results relevant to the Stanford3 pm laser are presented.IntroductionIt has long been known that noise has a fundamental role to play in the startup of freeelectron lasers. This problem has gained more attention recently with the planned operationof several FEL's using pulsed electron sources whose macropulse duration is only a few micro-seconds. These devices must turn on in as short a time as possible, so it is important thatthe startup be well understood. The evidence for anomalously long turn -on times in theStanford 3 pm FEL1 is an indication of possible problems in startup. The problem of theeffects of noise on laser devices in which pulse effects are important is a worthy problemin itself. Some work in this regard has already been done.

Wide bandwidth, high throughput monochromators for synchrotron radiation applications have been developed using Layered Synthetic Microstructures (LSM's). A double crystal LSM monochromator has been demonstrated with an energy resolution of 3% at 1.5 keV and a tuning range of 0.8 to 3.5 keV. In addition, techniques for extending the tuning range to lower energies as well as studies of substrate perfection using soft X-ray topography will be described.

A dedicated X-ray lithography system has been developed on Beam Line III-4 at the Stanford Synchrotron Radiation Laboratory (SSRL). The research program at SSRL includes studies of the spectral sensitivity of X-ray resists, mask characterization, and the applications of novel X-ray optics. The facilities available for this work and recent results in these areas will be described.

A study of Fresnel diffraction effects is presented for structures of interest for X-Ray Microlithography. This analysis uses the full optical constants of the mask absorber pattern. Therefore, our calculations take into account the fact that the photons experience a phase shift as they go through the mask's absorbing layer in addition to simple absorption. Results are presented which show the consequences of adding the phase effects to the Fresnel analysis. These results show that phase effects cannot be disregarded in modeling Fresnel intensity profiles on resists.