Exemplary embodiments provide high-quality layered semiconductor devices and methods for their fabrication. The high-quality layered semiconductor device can be formed in planar with low defect densities and with strain relieved through a plurality of arrays of misfit dislocations formed at the interface of highly lattice-mismatched layers of the device. The high-quality layered semiconductor device can be formed using various materials systems and can be incorporated into various opto-electronic and electronic devices. In an exemplary embodiment, an emitter device can include monolithic quantum well (QW) lasers directly disposed on a SOI or silicon substrate for waveguide coupled integration. In another exemplary embodiment, a superlattice (SL) photodetector and its focal plane array can include a III-Sb active region formed over a large GaAs substrate using SLS technologies.