Combinatorial Synthesis of (V$_{1-x}$,Cr$_{x})_{2}$GeC Epitaxial Films

We report the synthesis of solid solutions of (V$_{1-x}$,Cr$_{x})_{2}$GeC epitaxial films on single crystal Al$_{2}$O$_{3}$ epi-polished substrates. The materials are sputtered from four cathodes; three are powered by rf-power supplies while one is driven by a dc-power supply. The materials are co-deposited at a temperature of 900\r{ }C and we get solubility across the whole range of compositions. The substrate-film interaction creates a strain which makes the new phase energetically favorable. The surface structure was measured using atomic force microscopy revealing that the composition has little impact on this property. We found a new MAX-phase material, (V$_{0.5}$Cr$_{0.5})_{4}$GeC$_{3}$ , which has never been synthesized in bulk form. We report the conditions required to make these materials. In addition, electrical transport characteristics as a function of composition will be reported.