Prev: 6.1.5 Surface Propagation

6.2 Low-Pressure Processes

The general considerations from above work as starting point for the models of low-pressure processes commonly applied in semiconductor manufacturing. The processes include reactive ion etching (Section 6.2.1), plasma deposition (Section 6.2.2) and sputter deposition (Section 6.2.3).

The models for reactive ion etching and plasma deposition represent special cases of the general rate equation derived above and include two types of particles, namely, ions and neutral particles. For both models the sticking coefficient is assumed to be 1 and reflections are neglected. A different approach was used for the sputter deposition. Instead of assessing flux contributions for different species, the incidence characteristics where approximated by a single fitting function which comprises a large number of process parameters with only two phenomenological parameters.

In the following sections, the particular processes will be explained in detail. The chapter will be concluded by considerations about the run time requirements for the different models. The run times for the different processes will be compared against timings of a level set implementation.

Prev: 6.1.5 Surface Propagation