A process for forming strained semiconductor layers. The process include flowing a chlorine bearing gas (e.g. hydrogen chloride, chlorine, carbon tetrachloride, and trichloroethane) over the wafer while heating the wafer. In one example, the chorine bearing gas is flowed during a condensation process on a semiconductor layer that is used as a template layer for forming a strain semiconductor layer (e.g. strain silicon). In other examples, the chlorine bearing gas is flowed during a post bake of the wafer after the condensation operation.