Cr(2)GeC thin films were grown by magnetron sputtering from elemental targets. Phase-pure Cr(2)GeC was grown directly onto Al(2)O(3)(0001) at temperatures of 700-800 degrees C. These films have an epitaxial component with the well-known epitaxial relationship Cr(2)GeC(0001)//Al(2)O(3)(0001) and Cr(2)GeC(11andlt;(2) overbarandgt;0)//Al(2)O(3)(1andlt;(1)over barandgt;00) or Cr(2)GeC(11andlt;(2) over barandgt;0)//Al(2)O(3)(andlt;(1) over barandgt;2andlt;(1) over barandgt;0). There is also a large secondary grain population with (10andlt;(1)overbarandgt;3) orientation. Deposition onto Al(2)O(3)(0001) with a TiN(111) seed layer and onto MgO(111) yielded growth of globally epitaxial Cr(2)GeC(0001) with a virtually negligible (10andlt;(1) over barandgt;3) contribution. In contrast to the films deposited at 700-800 degrees C, the ones grown at 500-600 degrees C are polycrystalline Cr(2)GeC with (10andlt;(1) over barandgt;0)-dominated orientation; they also exhibit surface segregations of Ge as a consequence of fast Ge diffusion rates along the basal planes. The room-temperature resistivity of our samples is 53-66 mu Omega cm. Temperature-dependent resistivity measurements from 15-295 K show that electron-phonon coupling is important and likely anisotropic, which emphasizes that the electrical transport properties cannot be understood in terms of ground state electronic structure calculations only.
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