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The Engineering Test Stand (ETS) is an EUV lithography tool designed to demonstrate full-field EUV imaging and provide data required to accelerate production-tool development. Early lithographic results and progress on continuing functional upgrades are presented and discussed. In the ETS a source of 13.4 nm radiation is provided by a laser plasma source in which a Nd:YAG laser beam is focused onto a xenon- cluster target. A condenser system, comprised of multilayer-coated and grazing incidence mirrors, collects the EUV radiation and directs it onto a reflecting reticle. The resulting EUV illumination at the reticle and pupil has been measured and meets requirements for acquisition of first images. Tool setup experiments have been completed using a developmental projection system with (lambda) /14 wavefront error (WFE), while the assembly and alignment of the final projection system with (lambda) /24 WFE progresses in parallel. These experiments included identification of best focus at the central field point and characterization of imaging performance in static imaging mode. A small amount of astigmatism was observed and corrected in situ, as is routinely done in advanced optical lithographic tools. Pitch and roll corrections were made to achieve focus throughout the arc-shaped field of view. Scan parameters were identified by printing dense features with varying amounts of magnification and skew correction. Through-focus scanned imaging results, showing 100 nm isolated and dense features, will be presented. Phase 2 implementation goals for the ETS will also be discussed.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Engineering Test Stand (ETS) is a developmental lithography tool designed to demonstrate full-field EUV imaging and provide data for commercial-tool development. In the first phase of integration, currently in progress, the ETS is configured using a developmental projection system, while fabrication of an improved projection system proceeds in parallel. The optics in the second projection system have been fabricated to tighter specifications for improved resolution and reduced flare. The projection system is a 4-mirror, 4x-reduction, ring-field design having a numeral aperture of 0.1, which supports 70 nm resolution at a k{sub 1} of 0.52. The illuminator produces 13.4 nm radiation from a laser-produced plasma, directs the radiation onto an arc-shaped field of view, and provides an effective fill factor at the pupil plane of 0.7. The ETS is designed for full-field images in step-and-scan mode using vacuum-compatible, magnetically levitated, scanning stages. This paper describes system performance observed during the first phase of integration, including static resist images of 100 nm isolated and dense features.

Interband coregistration of multispectral satellite imagery is essential to exploiting the spectral information inherent in these data. A semi-automatic image registration method has been developed for Multispectral Thermal Imager (MTI) data. This registration method, based on feature fitting within the image, is applicable to the 14 MTI spectral bands that contain ground information; these spectral bands range from 0.45 to 10.7micrometers . The feature fitting registration method requires selection of an appropriate scene feature in the image, usually a crossroad or other feature with moderately high contrast to compute the required shift in x and y for each band. This paper describes the algorithm and provides examples of images registered using this method. Preliminary results show that for MTI image registration, feature fitting yields better results than cross-correlation. Results also show that this algorithm works well for a broad variety of scenes; this algorithm has been applied to images with scene content ranging from desert images with very little structure to heavily forested images. This method has been developed in support of the MTI mission, but may easily be extended for use on image data collected by other multispectral sensors.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A sensor system simulation has been developed which aids in the evaluation of a proposed fast framing staring sensor as it will perform in its operational environment. Beginning with a high resolution input image, a sequence of frames at the target sensor resolution are produced using the assumed platform motion and the contribution of various noise sources as input data. The resulting frame sequence can then be used to help define system requirements, to aid algorithm development, and to predict system performance. In order to assess the performance of a sensor system, the radiance measured by the system is modeled using a variety of scenarios. For performance prediction, the modeling effort is directed toward providing the ability to determine the minimum Noise Equivalent Target (NET) intensities for each band of the sensor system. The NET is calculated at the entrance pupil of the instrument in such a way that the results can be applied to a variety of point source targets and collection conditions. The intent is to facilitate further study within the user community as new mission areas and/or targets of interest develop that are not addressed explicitly during sensor conceptual design.

The Sandia EUV 10x microstepper system is the result of an evolutionary development process, starting with a simple 20x system, progressing through an earlier 10x system, to the current system that has full microstepper capabilities. The 10x microstepper prints 400-micrometers -diameter fields at sub- 0.10-micrometers resolution. Upgrades include the replacement of the copper wire target with a pulsed xenon jet target, construction of an improved projection optics system, the addition of a dose monitor a d an aerial image monitor, and the addition of a graphical user interface to the system operation software. This paper provides an up-to-date report on the status of the microstepper.