An improved delineation pattern for epitaxial depositions is created by forming a mask on a single-crystal silicon substrate which leaves an area (10) of the substrate exposed, doping the area with a dopant to create a doped region defined by a periphery, anisotropically, vertically etching the doped region to create a delineation pattern corresponding to the periphery, and then forming an epitaxial layer over the substrate and doped region. The periphery of the delineation pattern has a squared-off delineation step including a first step wall generally perpendicular to the surface of the substrate and a second step wall generally parallel to the surface of the substrate. The squared-off delineation step helps prevent wash-out of the delineation pattern as one or more epitaxial layers are deposited on the substrate.