Resist hardening by fluorocarbon plasma for electron-beam and optical mix-and-match lithographyOptimized design for the scattering with angular limitation in projection electron-beam lithography based electron projection system Low energy electron-beam proximity projection lithography: Discovery of a missing link Variable axis lens of mixed electrostatic and magnetic fields and its application in electron-beam lithography systems J.An alignment technique for electron-beam ͑EB͒ lithography that corrects the writing pattern to match the pattern-dependent lens distortion of an optical stepper is proposed. In mix-and-match EB and optical lithography, precise measurement of positional distortion caused by the stepper lens is necessary. However, recent research in optical lithography has shown that the lens distortion differs depending on the pattern features. Thus, we have enhanced the measurement method to reflect the pattern-feature dependence of positional distortion in optical lithography. To measure the various types of distortions more effectively, we modified the marks used for distortion and overlay measurement. The measured pattern dependence of the lens distortion was in good agreement with our simulation results and the overlay accuracy in mix-and-match lithography was improved with this method.

The mix-and-match use of an electron-beam (EB) lithography system and an optical stepper is an effective approach to achieving higher resolution while maintaining high throughput in the fabrication of Gbit DRAMs and advanced ASIC devices. In this approach, the highly accurate alignment of patterns exposed by different lithography methods is essential. In this paper, the lens distortion of the optical stepper is examined and distorted patterns are aligned with an EB lithography system. The overlay accuracy in this mix-and-match application was 51.4 nm (3σ) which corresponds to Gbit DRAMs fabrication.

Microfabrication techniques allow one to construct metallpolymer bilayers anchored at one end to a substrate end free to move at the other end. Electrically controlled 'fingers' were fabricated using the conducting polymer as an artificial muscle: doping and undoping the conjugated polymer causes a change in volume of this layer which results in bending of the bilayer. Grasping hands, fingers with sensing tips, and micropumps can be envisioned. Standing in the way of immediate fabrication are several materials challenges including layer adhesion, material compatibility, sacrificial layer improvement, and iow-temperature processing techniques.

Systems Development Laboratory, H i t a c h i , L t d . , Kawasaki, Japan 215 SUMMARY The RSA p u b l i c key cryptosystem i s one of t h e cryptosystems which can be a p p l i e d n o t only t o t h e s e c u r i t y p r o t e c t i o n b u t a l s o t o t h e v e r i f i c a t i o n s of o t h e r u s e r s and messages. It i s one of t h e most important techniques i n ensuring t h e s e c u r i t y of information.To c o n s t r u c t a secure RSA p u b l i c key cryptosystem, t h e key must be generated usi n g primes which are r o b u s t a g a i n s t a " ( p + 1) f a c t o r i z i n g a t t a c k . " For t h i s purpose, Gordon proposed a method of g e n e r a t i n g t h e key by s i e v i n g using known primes less than 8 b i t and by employing t h e higher-order exponential c a l c u l a t i o n . This paper i s an extension of Gordon's approach.The range of known primes i s defined optimally through an e v a l u a t i o n f o r t h e s i e v i n g primes less than 32 b i t . The expon e