Berlin 2005 – wissenschaftliches Programm
DS 11.4: Vortrag
Samstag, 5. März 2005, 15:15–15:30, TU HS110
The interaction of Al, Au, Ag, and Ti metal contacts with Pr2O3 thin films — •Mohamed Torche and Dieter Schmeißer — Angewandte Physik-Sensorik, BTU Cottbus, Postfach 10 13 44, D-03013 Cottbus, Germany
Pr2O3 is one of the promising high-k oxides desirable to replace SiO2 for the sub-100nm field-effect transistors (FETs) and dynamic random access memory (DRAM) capacitors. Here we focus on the metallic contacts used for the MOS and MIM based structures. With the thickness of Pr2O3 being around 3nm the metal interaction is crucial to avoid a reduction of the dielectric properties by metal percolation, crack filling or diffusion processes. We use XPS and SRPS to study the initial interaction as well as the thermal stability of metals (Al, Ag, Au, and Ti) on Pr2O3 films. We show that Al, Ag, Au form initial metallic layer which react already at temperatures around 300∘C. In contrast, Ti is found to be more stable than the other metals. We determine the formation of Ti-oxides at the Ti / Pr2O3 interface and its thermal stability. Ti is found to build a good diffusion barrier between the oxide and the metal.