Combinatorial synthesis and high-throughput phase and transport properties analysis of Fe-Si-Ge thin film libraries
Andrej Furlan, MEMS Materials, Faculty of Mechanical Engineering, Institute for Materials, Ruhr-Universität Bochum, Bochum, GermanyQuentin D’Acremont, Laboratoire Ondes et Matière d’Aquitaine (LOMA - UMR CNRS 5798), Université de Bordeaux, Amplitude Systèmes, 11 Avenue de la Canteranne, 33600 Pessac, France, Talence, FranceGilles Pernot, Laboratoire d\'Energétique et de Mécanique Théorique et Appliquée (LEMTA – UMR 7563), Université de Lorraine, Vandoeuvre-lès-Nancy, FranceGeorg Madsen, CMAT, ICAMS, Ruhr-Universität Bochum, Bochum, GermanyStefan Dilhaire, Laboratoire Ondes et Matière d’Aquitaine (LOMA – UMR CNRS 5798), Université de Bordeaux, Talence, FranceAlfred Ludwig, MEMS Materials, Faculty of Mechanical Engineering, Institute for Materials, Ruhr-Universität Bochum, Bochum, Germany
Silicides are an integral part of several important technologies but current systematization of their properties is fragmented and incomplete. In this study, our focus is on the Fe-Si-Ge system where we examine the distribution of the already known stable Fe-Si and Fe-Ge binary phases and probe the system for potential Fe-(Si/Ge) alloys and ternary phases. Since there is a potential for application of compositions from the Fe-Si-Ge system as thermoelectrics, there is an urgent need for systematic determination and understanding of their transport properties. Moreover, so far no systematic study of a complete phase diagram of the Fe-Si-Ge system is available.
Here, a novel approach of studying silicides is presented. It consists of combining the combinatorial deposition approach and high-throughput analysis methods for determination of structural and transport properties of the coatings for the full range of content for all three alloying elements. A novel high-throughput method to measure the thermal conductivity of sputtered material libraries is also introduced. The Fe-Si-Ge thin film libraries were deposited by a wedge-type multi-layer approach by annealing induced interlayer diffusion, and co-deposition on hot substrate. The phase-formation analysis in dependence of the film composition and the deposition methods, as examined by XRD and grazing-incidence synchrotron radiation diffraction is reported. The transport properties in the form of thermal and electrical conductivities are investigated and correlated to the determined stable phase and alloy distributions for the wide composition range of the investigated ternary system.
It is found that the two different deposition approaches induce different phase formation, and low tendency to crystallization is detected, particularly for the multi-layer approach. The plausibility of integrated combinatorial control of phase stability and electrical and thermal transport properties for ternary silicide systems is also demonstrated.