Comparison of silicon stencil mask distortion measurements with finite element analysis

Stencil mask fabrication processes using silicon-on-insulator (SOI) mask-wa fer blanks have already been established. In order to meet the stringent re quirements of pattern placement both mask distortion measurements and finit e element analyses serve as tools to understand the sources of the pattern distortions. In this article experimental results from LMS IPRO measurement s in intermediate process steps and comparison to corresponding finite elem ent analyses of two stencil masks are presented, demonstrating the decisive influence of SOI mask-wafer blank quality, in particular with respect to t he warp of the wafer substrate and thickness homogeneity of the silicon mem brane layer. (C) 1999 American Vacuum Society. [S0734-211X(99)13206-2].