Author(s)

A. Voigt, B-G. Wang, K-H. Hoffmann, D. Wulff-Molder

Abstract

Simulation and control of industrial crystal growth of A. Voigt\ B.-G. Wang*, K.-H. Hoffmann' & D. Wulff-Molder^ ^ nanotechnology -crystal growth, caesar, Germany *Korth Kristalle Ltd., Germany Abstract Single crystals of BaF^ can be used as optical materials in the next genera- tion of micro-lithography steppers. They are usually grown by the vertical Bridgman method but cannot be produced in sufficient quantity and qual- ity for that application. We present a mathematical model and numerical simulations which help to design the growth process in order to overcome these technological difficulties. 1 Introduction Lithography tools currently being used to exposure wafers for integrated circuits manufacturing use a 248nm eximer laser light source. The next generation of exposure tools will use 193 and 157mm lasers to support feature sizes down to 0.18 and 0.10/zra. When exposed to 157 nm radiation, the actual optical quartz undergoes fluence dependent compaction and induced absorpt

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