Step Coverage Simulation for Non-liner Surface Reaction

Step coverage simulation code was newly developed. This code, which is a kind of test particle Monte Carlo method, can simulate the step coverage with non-liner surface reaction, for example Tungsten (W) thermal Chemical Vapor Deposition (CVD) using hydrogen (H_2) and hexafluoro Tungsten (WF_6). The availability of this code was examined by the comparison of the experimental obtained step coverage and simulated one through W-CVD. The simulation results well explained the WF_6 concentration dependency of step coverage of W film grown on the silicon substrate. The step coverage of film grown at 773K and in low WF_6 concentration becomes poor coverage, however the film grown in high WF_6 concentration shows good coverage. Under high WF_6 concentration, the growth rate reaches the ceiling, namely the growth rate have the same value on the any position in the trench, and consequently the step coverage became good