High Resolution E-Beam Lithography With The VLS-1000 Performance Of The Microseal Vacuum Interface

Abstract

In the past few years, e-beam technology has gained acceptance as a viable production technique for lithography. This is particularly so in the mask-making areas of semiconductor manufacturing. Only a few manufacturers of semiconductor devices have begun to use e-beam lithography directly in the lab line. This has not been because of a lack of technology but rather lack of good economics. E-beam technology has been suitable for mask-making bectuse the economics make sense, and the mask quality is far superior to that obtained with optical techniques. E-beam has not been suitable for direct writing on the wafer because the throughputs have not been at a level which would make direct write economically viable. Major efforts have been underway by several semiconductor equipment manufacturers to develop a new generation of electron beam lithography systems for direct write on wafer applications. These development efforts are now coming to fruition. One such system is the VLS-1000. The VLS-1000 is a variable shaped electron beam lithography system optimized for direct write on the wafer. This system incorporates several innovative technologies to overcome the hurdles of low throughput and high system cost. A brief description of the system will be given highlighting some of these innovative technologies. One of these, the microseal, has allowed a significant reduction in system size and cost. The microseal allows introduction of wafers directly into the system without the normal incompatibilities and difficulties of vacuum chambers and vacuum locks. Performance results of the microseal will be given. The use of e-beam technology is most viable in the submicron range of feature sizes. Although high accuracy and high. throughput present design conflicts, the use of rigorous error and throughput budgets has allowed the VLS-1000 to provide the highest accuracy performance and competitive throughputs.