Process for forming and locating buried layers.

A method for forming vertically spaced apart regions on an integrated circuit substrate is disclosed. One or more recesses are formed in inactive regions of the substrate, while the remaining surface of the substrate remains substantially flat. When an epitaxial layer is deposited over the substrate, the recesses in the substrate causes the formation of corresponding recesses in the exposed surface of the epitaxial layer. Such recesses are useful as alignment marks in properly locating the masks used in defining active regions on the surface of the epitaxial layer.