TOMCAT 2002 Release

 TOMCAT is a general-purpose Monte Carlo simulator of particle transport in 1-D and arbitrary 2-D and 3-D structures (TOpography based Monte CArlo Transport). The main application of TOMCAT is in the simulation of Ion Implantation, using the physically-based models of UT-MARLOWE 5.0. In this capacity, TOMCAT is capable of simulating implants into arbitrary surface topography and window size.

The standard approach to 2-D/3-D simulation of ion implantation has been to make use of 1-D profiles, obtained either by simulation or experiment. These are then given a lateral Gaussian tail, or some similar approximation is made. Other simulators (e.g. FLOOPS) use point response profiles (simulations of implants into very small windows) as Green's functions to the large-window implant problem, superposing the point responses over the entire topography.

Both approaches are approximate, neglecting the detailed effects of transport through varying topography and materials, as well as damage build-up in the crystalline regions. Using an older Monte Carlo simulator such as UT-MARLOWE for implants into large structures has not been practical, due to the very long computation times involved. Using numerous algorithms to enhance the computational efficiency of ion implant simulation, TOMCAT is able to perform simulations into large structures in a reasonable amount of time, eliminating or reducing the need for approximate 2-D/3-D analytic models.