A STRIDE towards practical 3-D device simulation-numerical and visualization considerations

A 3-D device solver (STRIDE), capable of solving grids up to 250,000 nodes, has been developed on a message passing multiprocessor. By the use of iterative matrix solvers and Gummel style nonlinear iteration schemes, user memory per node is reduced over use of direct solvers and Newton schemes. By using an independent-edge-grouping scheme to increase the vector length to the order of the number of variables, the vector processing efficiency is significantly increased without additional floating point operations. The modified-singular-perturbation (MSP) scheme is extended to two-carrier simulations. This significantly speeds up the convergence rate of Gummel style nonlinear iterations. Physical insight gained from the MSP schemes also leads to an automatic switching scheme between various nonlinear schemes based on the monitoring of certain matrix parameters. Application of STRIDE is demonstrated by an analysis of latchup trigger current dependence on layout arrangement