The present invention provides a method for manufacturing a semiconductor device. The method, in one embodiment, includes forming a silicon oxide masking layer over a substrate in a first active region and a second active region of a semiconductor device, patterning the silicon oxide masking layer to expose the substrate in the first active region. The method further includes forming a layer of dielectric material over the substrate in the first active region, the patterned silicon oxide masking layer protecting the substrate from the layer of dielectric material in the second active region.