Three-dimensional level set based Bosch process simulations using ray tracing for flux calculation

This paper presents three-dimensional simulations of deep reactive ion etching processes, also known as Bosch processes. A Monte Carlo method, accelerated by ray tracing algorithms, is used to solve the transport equation, while advanced level set techniques are applied to describe the movement of the surface. With multiple level sets it is possible to describe accurately the different material layers which are involved in the process. All used algorithms are optimized in such a way. that the costs of computation time and memory scale more like with the surface size rather than with the size of the simulation domain. Finally the presented simulation techniques are used to simulate the etching of holes, whereas the influence of passivation/etching cycle times and hole diameters on the final profile is investigated. (C) 2009 Elsevier B.V. All rights reserved.