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Rhodium Schottky barrier contacts on germanium substrates are investigated in terms of electrical, physical, and chemical properties. The Rh, deposited by electron beam evaporation on a n-type (100)-Ge substrate, has been annealed in N2H2at different temperatures ranging from 450°C up to 800°C. Rh/Ge Schottky diodes were fabricated to extract the Schottky barrier height, the ideality factor as well as the forward to backward current ratio. By using various analyzing techniques such as Atomic Force Microscopy (AFM), X-ray Diffraction (XRD), Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS), and High-resolution Transmission Electron Microscopy (HR-TEM), the formation of polycrystalline Rh-germanide RhxGeyphases has been proven. At 500°C germanidation temperature an effective SBH of 0.59 eV is extracted showing a high current ratio of 5 × 103and a remarkable low ideality factor of 1.07.

We present a study on LaxZryOz, LaxAlyOz, and various combinations of these in high-κ dielectric stacks together with Al2O3. We use atomic layer deposition to fabricate ultrathin layers and laminates in the few-nanometer range at process temperatures of 250°C. By means of metal gate/high-κ oxide/semiconductor capacitors we evaluate these materials regarding their electrical properties and thermodynamic stability on silicon substrates. We observe that superior electrical characteristics are achieved if a thin layer of LaxZryOzis sandwiched between two Al2O3layers about 1nmthick. By this approach, hydroxylation of the La-containing oxides is suppressed, minimizing leakage currents as well as oxide and interface charges.