The chemistry and transport phenomena of chemical vapor deposition of silicon from SiCl4

The chemical vapor deposition (CVD) of silicon is among the most important synthesis methods in electronic industry. We developed and applied novel methods of characterization to studies of CVD of Si from SiCl₄. In particular, we studied the chemistry of the Si-Cl-H system as well as transport phenomena, such as the momentum, heat, and mass transport in a horizontal CVD reactor. A flow visualization was used to study the flow dynamics, i.e., the momentum transport in the reactor. The heat transport was studied by measuring temperatures at various points in the reactor as a function of flow-rates and susceptor temperatures. A specially designed movable probe was used for a mass spectrometric sampling in the reactor. In these experiments, we were able to determine quantitatively partial pressures of reactants and products at some desired location in the reactor, thus studying the mass transport during the CVD of Si. The conducted studies of transport phenomena were used to establish a model which can be used to predict the efficiency and uniformity of the deposition.