  By magnetron co-sputtering, thin films of a nominal Cr2CoGa compound were
deposited on MgO and MgAl2O4. To achieve crystallisation in the inverse Heusler
structure, different heat treatments were tested. Instead of the inverse
Heusler structure, we observed phase separation and precipitate formation in
dependence on the heat treatment. The main precipitate is Cr3Ga in A15
structure. The remainder forms Co-rich CoGa in the B2 structure and possibly
Cr-rich CoCr in the sigma-phase.
