A process for the formation of an epitaxial layer on a semiconductor wafer is described which inhibits the formation of thermal stress in the semiconductor wafer such as a silicon wafer, during the formation of such an epitaxial layer thereon. In one aspect, such thermal stress is inhibited during the deposition of the epitaxial material by initially reducing the deposition rate to less than 1 .mu.m per minute or lower until the epitaxial layer reaches a thickness of from about 2 to about 30 .mu.m. In another aspect of the invention, any bridge materials formed between the wafer and the wafer support, during formation of the epitaxial layer, is removed before the wafer is cooled, i.e., before such bridge materials can induce thermal stress in the wafer during the cooling of the wafer, by post etching the wafer with HCl etching gas after the epitaxial deposition.