Characterization and dielectric properties of GeOx thin films prepared by radio frequency (RF) reactive sputtering

Dielectric properties of germanium oxide have not been investigated in detail. But, it has been investigated from an optical viewpoint as light waveguide materials. Its electrical properties have rarely been studied for electronic device applications.We have examined the previous investigations on Ge–O films deposited by radio frequency (RF) reactive sputtering. The dissipation factor tan δ, the capacitance per area, the breakdown field of GeOx films were studied as well as its composition by RBS analysis. Aiming at obtaining the higher value of the dielectric constant or capacitance per area, we have attempted to fabricate Ge–Pb–O films by the same deposition method. An optimization of the dielectric properties of these materials has been done, using the best conditions of sputtering for each oxide, the alternated pile layers as dielectric multilayer capacitors and thermal treatments.These dielectric properties have been improved by thermal treatments, and the dielectric multilayer made with alternated GeO2 and Ge–Pb–O films capacitors has a breakdown field superior to that of each simple layer.