Synthesis of Cr₂AlC thin films by reactive magnetron sputtering

Cr₂AlC thin films are deposited on MgO (100) and Al₂O₃ (0001) substrates with reactive radio frequency (RF) magnetron sputtering for the first time. Single phase Cr₂AlC films are synthesized at a substrate temperature of 480 °C and deposition power of 70W, with a preferred orientation. The film is polycrystalline with a dense microstructure. The preferred orientation disappears and AlCr₂ impurity emerges as the temperature and sputtering power rise during the deposition. When the sputtering power is 90 W or higher, the phase becomes totally AlCr₂ due to C loss. The Cr₂AlC phase is stable in vacuum for temperatures up to 700 °C, but the phase starts to decompose into Cr₇C₃ at 800 °C.