Formation of non-equilibrium sputtered Cr films used in thin film HD recording media

Formation and phase transformation of non-equilibrium /spl delta/-A15 Cr thin films prepared by r.f. magnetron sputtering have been characterized. Processing parameters such as working pressure, deposition time and temperature were found to affect the formation of /spl delta/-A15 Cr films. We have demonstrated for the first time that the phase transformation of the /spl delta/-A15 Cr phase to the equilibrium /spl alpha/-BCC Cr phase is an irreversible, exothermic, first-order transition. Onset and peak temperatures of the transformation were determined to be 4280C and 437/spl deg/C, respectively, at a heating rate of 100C/mln. Our post-deposition annealing study by X-ray diffraction further verified the occurrence of transformation.