A semiconductor device including a germanium containing substrate including a gate structure on a channel region of the semiconductor substrate. The gate structure may include a silicon oxide layer that is in direct contact with an upper surface of the germanium containing substrate, at least one high-k gate dielectric layer in direct contact with the silicon oxide layer, and at least one gate conductor in direct contact with the high-k gate dielectric layer. The interface between the silicon oxide layer and the upper surface of the germanium containing substrate is substantially free of germanium oxide. A source region and a drain region may be present on opposing sides of the channel region.