A program package is presented named CAPCAL that provides a method for calculation of the 3-D electric field distribution due to multilayer metallization of advanced VLSI (very large-scale integration) integrated circuits. The underlying physics and numerical modeling techniques used by CAPCAL are described. The finite-difference method together with a multigrid solver is used to permit easy program handling and full portability. Example capacitance calculations are presented for structures typical of the wiring of a memory cell. The influence of the line spacing and the permittivity of the passivation layer on the parasitic capacitances are also investigated. The codes developed have been tested on various computers down to the size of a microcomputer, and thus can be installed on every system currently in use for CAD.>

A new two-dimensional process modeling program written in Fortran is described. For the first time, this program allows the simulation of all important processing steps occurring in typical sequences involved in the fabrication of integrated circuits such as doping, oxidation, lithography, etching, and layer deposition. The program possesses a modular structure to allow for easy changing and improvement of process models as well as of mathematical procedures. The program is menu driven to make it easy to use for non-experts and it is readily usable with different computer systems.

In semiconductor modeling, partial differential equations often have to be solved on a domain with a curved boundary. A numerical conformal mapping well suited for process modeling problems is presented. Its use in connection with a moving boundary is explained.