Optical lithography is the technology used to create high-
density VLSI computer circuit patterns. It is fair to say that
small improvements and tighter control of a lithographic process
usually lead to improved device yield and device performance.
Significant advances in lithography often lead to big
competitive advantages for manufacturers. Advancing lithographic
technology is not easy. Evaluating engineering proposals is
often very expensive. Mathematical modeling of lithography
process steps often allows faster evaluation of new lithographic
ideas and consequently cuts cost substantially. In this talk I
will discuss models and the results of models used to simulate
the three basic steps used to create photoresist patterns for
VLSI circuits, i.e. (1) the 3D optical imaging and exposure
step, (2) the 3D exposure product redistribution by diffusion
during the very important bake step, and (3) the 3D dissolution
of the exposed material during the development step. A video of
the 3D dissolution process computed