Selective epitaxial growth of silicon

We have studied selective epitaxial growth of silicon in the SiCl₂H₂/HCl/H₂system. Our results on growth rate and selectivity are reported here. We found that the growth rate and selectivity are strong functions of the partial pressures of HCl, SiCl₂H₂, H₂, exposed Si area, and wafer position. We propose that growth and selectivity are controlled by surface reactions between SiCl₂H₂and HCl and the SiO₂and Si surfaces. Higher HCl flow rates decrease the adsorption coefficients and/or incorporation rates of the reactive SiCl₂H_2(g)species on both SiO₂and Si. When either is zero for SiO₂and both are greater than zero on Si, selective depositions occur. Finally, we present data on the effect various SiO₂surface treatments have on the density and distribution of Si nuclei on this surface.