Structure and method for forming hybrid substrate

A first and a second substrate are bonded together to thereby form a unitary hybrid substrate. Predefined portions of the first substrate are removed to form openings in the first substrate through which surface regions of the second substrate are exposed. A selective epitaxial growth process that is selective with respect to the crystalline orientations of the first and second substrates is carried out to thereby form epitaxial silicon from the exposed surfaces of the second substrate but not from exposed surfaces of the first substrate. The epitaxial silicon formed from the exposed surfaces of the second substrate has the same crystalline orientation as the second substrate.