Charge–exchange spectroscopy is widely used to determine the profiles of fully stripped low-Z ions (carbon, oxygen, neon) in fusion plasmas. Continuing interest in the use of heavier impurities for radiative cooling in boundaries and divertors of fusion plasmas has encouraged the expansion of this technique for elements such as argon which are not completely burned out in present machines. As a first step, it has been necessary to predict the wavelengths of transitions from Ar XVI to Ar XVIII from theoretical calculations. Several of these have been detected in the DIII-D tokamak [Plasma Physics Controlled Nuclear Fusion Research, 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] subsequent to argon puffing into neutral-beam injected plasmas, and the experimentally determined wavelengths are in good agreement with the predicted values. Argon ion densities have been determined using recent Classical Trajectory Monte Carlo (CTMC) computations of the charge–exchange cross sections, and some radial profiles for specific ionization stages have been measured.

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A new reticle inspection system with three parallel scanning laser beams for UV imaging for both contamination and pattern inspection has been developed to detect defects on advanced reticles for DUV steppers and low k 1 lithography for .13um and extensions to .10um design rules. The development of the new three beam architecture at UV wavelength has significantly increased system throughput while improving the resolution of the imaging optics for inspecting advanced reticles including Halftone, Tri-Tone, and Alternating PSM's and reticles with aggressive OPC. The system is capable of running multiple inspection algorithms simultaneously in transmitted and reflected light to achieve concurrent pattern and STARlight TM inspection, thus improving both sensitivity and inspection thoroughness with a single inspection. These improvements enable fast inspections of reticles for 4X lithography design rules at 0.18um, 0.15um and 0.13um.Initial simulations were performed to optimize performance of optical components and a new defect detection algorithm. The simulations identified that with the optics changes to achieve three beam scans and with new algorithms, the inspection was more sensitive to all defect types including on edge contamination defects, which can be particularly difficult to detect. Using both PSL and programmed defect test masks and real production reticles, initial observations of the nature and the frequency of defects detected with this 100nm sensitivity instrument will be presented.With more defects to review, the system software provides concurrent or remote defect review so time to disposition defects does not effect system inspection capacity. With smaller defects to review the quality of defect review images has a direct impact on the effectiveness and ease-of-use of reticle inspections systems. The smaller review pixel with the system combined with a suite of review imaging tools, yields high quality images for defect dispositioning.

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