Device modeling for advanced integrated circuits

Exact solutions for semiconductor problems require, more often than not, the use of numerical methods. While a numerical solution offers precision, an approximate-analytic solution provides convenience and physical insight, thus the two approaches are complementary. Solving problems numerically has become increasingly popular because of the growing pervasiveness of computers, but there are still many cases wherein an approximate analytic approach is preferred. Approximate analytic models for inversion and accumulation layers are developed in the context of the general solution. Approximate-analytic modeling of the BJT and the MOSFET is described using these results, and using the depletion approximation replacement (DAR). A study of the 3-dimensional integrated circuit is also included. Specifically, the results of the investigations on the processing technology, device and circuit options for the all-semiconductor 3-D ICs are presented.