An integrated silicon and III-N semiconductor device may be formed by growing III-N semiconductor material on a first silicon substrate having a first orientation. A second silicon substrate with a second, different, orientation has a release layer between a silicon device film and a carrier wafer. The silicon device film is attached to the III-N semiconductor material while the silicon device film is connected to the carrier wafer through the release layer. The carrier wafer is subsequently removed from the silicon device film. A first plurality of components is formed in and/or on the silicon device film. A second plurality of components is formed in and/or on III-N semiconductor material in the exposed region. In an alternate process, a dielectric interlayer may be disposed between the silicon device film and the III-N semiconductor material in the integrated silicon and III-N semiconductor device.