Shape of film grown on microsize trenches and holes by chemical vapor deposition: 3-dimensional Monte Carlo simulation

A semi-microscale 3-dimensional film growth simulation code using a simple Monte Carlo method was developed. This code predicts the step coverage on a trench and a hole of arbitrary shapes and requires much smaller computer memory size and less calculation time than the Direct Simulation Monte Carlo (DSMC) method. The simulation code was evaluated by comparing the results with experimental results of a zirconia (ZrO2) him grown on a hole. The experiments and/or 3-dimensional simulations indicated that the film grown on the side and bottom walls of a hole is thinner than that of a 2-dimensional trench, and complete occlusion of a hole is more difficult compared with a trench with opening width equal to the hole diameter. The surface reaction rate constant is the most important factor in the occlusion process. When the reaction rate constant is small, the hole is occluded with a thin film. However, when the reaction rate constant is large, there remain a void inside and a small unfilled pinhole through the thick film grown on the top.