High amount cluster incorporation in initial Si film deposition by SiH ₄ plasma chemical vapor deposition

We have carried out in-situ measurements of Si cluster volume fraction in Si films during plasma chemical vapor deposition by using quartz crystal microbalances (QCM's) together with a cluster-eliminating filter. The cluster volume fraction in films is deduced from film deposition rates with and without Si clusters using QCM's. By employing this method we have revealed a depth profile of the Si cluster volume fraction. A high cluster volume fraction is observed in the initial phase of film deposition. This behavior is compared with time evolution of SiH*, Si* emission intensities and their intensity ratio.