Acknowledgments
This work was performed at Sandia National Laboratories. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. The authors gratefully acknowledge financial support from Intel Corporation under CRADA SC93/01154 and technical interactions with Kevin J. Orvek, Intel contract monitor, David Y. H. Pui and Jing Wang, University of Minnesota, and Christof Asbach and Heinz Fissan, IUTA.