Abstract: A monolithically integrated, multi-layer device is fabricated with single crystal films of desired orientation grown from arrayed nucleation sites on amorphous and/or non-single crystal surfaces. Examples of devices which can be produced are CMOS and bipolar devices in single crystal (100) and (111) Si films on amorphous surfaces such as SiO2 or Si3N4 in processed ULSIC wafers. These devices can be integrated along the 3rd dimension. Thus, 3-dimensional IC's can be fabricated. Similarly, high performance CMOS devices in SiGe films, MESFET, HEMT and optical devices in compound semiconductor films, can be fabricated within processed ULSIC wafers. Further, Si—, GaAs—, and other compound semiconductor-based devices in the respective single crystal films with different orientations deposited selectively in a given level, and in multilevel IC's, can be manufactured.