A Near-Term, High-Confidence Heavy Lift Launch Vehicle

The use of well understood, legacy elements of the Space Shuttle system could yield a near-term, high-confidence Heavy Lift Launch Vehicle that offers significant performance, reliability, schedule, risk, cost, and work force transition benefits. A side-mount Shuttle-Derived Vehicle (SDV) concept has been defined that has major improvements over previous Shuttle-C concepts. This SDV is shown to carry crew plus large logistics payloads to the ISS, support an operationally efficient and cost effective program of lunar exploration, and offer the potential to support commercial launch operations. This paper provides the latest data and estimates on the configurations, performance, concept of operations, reliability and safety, development schedule, risks, costs, and work force transition opportunities for this optimized side-mount SDV concept. The results presented in this paper have been based on established models and fully validated analysis tools used by the Space Shuttle Program, and are consistent with similar analysis tools commonly used throughout the aerospace industry. While these results serve as a factual basis for comparisons with other launch system architectures, no such comparisons are presented in this paper. The authors welcome comparisons between this optimized SDV and other Heavy Lift Launch Vehicle concepts

25th Annual Midwest/Midsouth Estate Planning Institute

Materials from UK/CLE\u27s 25th Annual Midwest/Midsouth Estate Planning Institute held in July 1998

• ROTHSCHILD ET AL. Recent Trends in Optical Lithography Recent Trends in Optical Lithography

■ The fast-paced evolution of optical lithography has been a key enabler in the dramatic size reduction of semiconductor devices and circuits over the last three decades. Various methods have been devised to pattern at dimensions smaller than the wavelength used in the process. In addition, the patterning wavelength itself has been reduced and will continue to decrease in the future. As a result, it is expected that optical lithography will remain the technology of choice in lithography for at least another decade. Lincoln Laboratory has played a seminal role in the progress of optical lithography; it pioneered 193-nm lithography, which is used in advanced production, and 157-nm lithography, which is under active development. Lincoln Laboratory also initiated exploration of liquidimmersion lithography and studied the feasibility of 121-nm lithography. Many of the challenges related to practical implementation of short-wavelength optical lithography are materials-related, including engineering of new materials, improving on existing materials, and optimizing their photochemistry. This article examines the technical issues facing optical lithography and Lincoln Laboratory’s contributions toward their resolution. Optical lithography, the technology of patterning, has enabled semiconductor devices to progressively shrink since the inception of integrated circuits more than three decades ago. Throughout the 1980s and 1990s, the trend of miniaturization continued unabated and even accelerated. Current semiconductor devices are being mass produced with 130-nm dense features; by 2007 these devices will have 65-nm dense features. Optical lithography has been, and will remain for the foreseeable future, the critical technology that makes this trend possible. (To learn the fundamentals of optical lithography, see the sidebar entitled “Optical Lithograph