GeO2 based high k dielectric material synthesized by sol–gel process

Recently, there has been lot of research on new high dielectric constant (high k) materials for use in future generations of ultra-large scale integrated circuits (ULSI). There are number of requirements for the new high k materials, such as high dielectric constant, thermal stability (400 °C or higher), high mechanical strength, and good adhesion to neighboring layers. Keeping in view the properties required for the replacement of existing SiO2 dielectrics, new high k dielectric material based on GeO2 has been synthesized. Polycrystalline GeO2 thin films have been deposited by simple, and cost effective sol–gel spin coating process. The obtained xerogel films of germanium oxide have been annealed at 400 °C, 600 °C and 800 °C for 3 h in argon atmosphere. Elemental composition, morphology, and phase analysis have been measured by employing X-ray photoelectron spectroscopy, scanning electron microscopy, and X-ray diffraction techniques, respectively. The formation of the hexagonal GeO2 phase at and above 400 °C has been reported. The composition of the annealed films have been measured and found to be 68 at.% of O, 32 at.% of Ge for GeO2, which are close to the stoichiometry of the GeO2.