Dresden 2014 – scientific program
DS 49.9: Talk
Friday, April 4, 2014, 12:00–12:15, CHE 91
Structural changes in HfO2 thin films: thickness and doping dependence — •Simone Brizzi1, Massimo Tallarida1, Christoph Adelmann2, Lars-Ake Ragnasson2, Sven Van Elshocht2, and Dieter Schmeisser1 — 1Brandenburg University of Technology, Konrad-Wachsmann Allee 17, 03046 Cottbus, Germany — 2Imec, Kapeldreef 75, B-3001 Leuven, Belgium
In this work we show results regarding MOCVD and ALD HfO2 as well as Al-doped HfO2. We use Synchrotron Radiation Photoemission Spectroscopy (SRPES) to determine Hf/O atomic ratios and X-ray Absorption Spectroscopy (XAS) to investigate the electronic properties related to their crystallization. MOCVD films are synthesized at temperatures ranging from ambient to 400∘C and show structures from completely amorphous to monoclinic. ALD films are amorphous as deposited, and can crystallize after post-deposition anneal depending on the percentage of Al-doping. We discuss PES results in order to determine how close to stoichiometry the Hf/O atomic ratios of the films are, as well as the doping level. From XAS data, instead, we can point out how orbital hybridizations are related to structural and physical properties.