Vapour growth mechanism of silicon layers by dichlorosilane decomposition

This work aims to calculate the growth rates of epitaxial and polycrystalline Si from the SiH 2Cl 2-H 2 system by using a simple kinetic model for the heterogeneous reaction. The growth process assumes reaction sequences which differ according to the high, low or intermediate value of the substrate temperature. The kinetic analysis is carried out by including the homogeneous and heterogeneous equilibria established in the system and by using the steady-state approximation. According to the rate equations found, which are in good agreement with the experimental data, the Si growth rate is proportional to the SiH 2Cl 2 concentration in the gas phase, irrespective of temperature, and depends on P -1/2 H 2 or P -1 H 2 for different pressuress of the system. In the homogeneous mechanism, the Si growth rate depends only on the SiH 2Cl 2 concentration.