A method of fabricating a semiconductor structure utilizing doped silicate glass on a substrate of a wafer. The method includes the step forming a modulation doped silicate glass structure over a first layer of the wafer. The modulation doped silicate glass structure is formed by depositing at least two alternating layers of heavily-doped silicate glass and lightly-doped silicate glass over the first layer. Both the heavily-doped silicate glass and lightly-doped silicate glass layers may comprise glass doped with both a first dopant and a second dopant. The first dopant may represent, for example, phosphorous, and the second dopant may represent, for example, boron.