Embodiments of the present disclosure describe semiconductor devices comprised of a semiconductor substrate with a metal oxide semiconductor field effect transistor having a channel including germanium or silicon-germanium, where a dielectric layer is coupled to the channel. The dielectric layer may include a metal oxide and at least one additional element, where the at least one additional element may increase a band gap of the dielectric layer. A gate electrode may be coupled to the dielectric layer. Other embodiments may be described and/or claimed.