A substrate for a semiconductor device is disclosed including, in one embodiment, a plurality of semiconductor-on-insulator (SOI) wafers bonded to one another in a single stack. A distal end of the stack includes a first SOI region with a first semiconductor layer having a thickness and a first surface orientation. A surface of the single stack may further include a non-SOI region and/or at least one second SOI region. The non-SOI region may include bulk silicon that extends through all of the insulator layers of the single stack and has a thickness different than that of the first silicon layer. Each second SOI region has a second semiconductor layer having a thickness different than that of the first semiconductor layer and/or a different surface orientation than the first surface orientation. The substrate thus allows formation of different devices on optimal substrate regions that may include different surface orientations and/or different thicknesses and/or different bulk or SOI structures.