Material and Electrical Characterization of Ni- and Pt-Germanides for p-channel Germanium Schottky Source/Drain Transistors

The lack of a stable native germanium oxide has been the main obstacle for the use of Ge in complementary metal oxide-semiconductor CMOS devices. However, recent development of next generation deposited high-k gate dielectrics for Si also allows for the fabrication of high performance Ge-based metal-oxide-semiconductor field effect transistors (MOSFETs). For the formation of electrical contacts in Ge-based MOSFETs, transition metal germanides, such as Ni and Pt germanides, appear to be suitable candidates for this application due to their low resistivity, low formation temperatures (as low as 250degC), and ability to form in self-alignment. In this work, we have characterized the material and electrical properties of nickel and platinum germanide films as Schottky source/drain contacts for Ge-MOSFETs. This talk will present and discuss experimental results on Ni- and Pt-germanide phase formation, interfacial/surface morphology and Schottky barrier heights in Ni&Pt-germanide contacts formed by the solid state reaction of Ni/Ge(001) and Pt/Ge(001)