Films of Mn_(1.56)Co_(0.96)Ni_(0.48)O_4, 6-10 mu m thick, were RF-magnetron sputtered onto the high temperature lift-off polyimide PiRL(circle R) (made by Brewer Science, Inc.), and patterned into long, narrow beams using photolithography. The beams would self-delaminate, curling towards the substrate upon cooling from 300 deg C to room temperature after sputtering, as a result of the stress gradient in the film, caused by the deposition process. The typical radius of curvature is 8000 mu m. Upon annealing at temperatures as low as 250 deg C for 10 minutes, the delaminated films continue to curl. The films curl to equilibrium radii that are functions of the annealing atmosphere and temperature. Films annealed in H_2/N_2 or vacuum curl more slowly than inair. TEM reveals that the first 100 nm of film is relatively porous, nanocrystalline spinel which densify instantaneously when exposed to high electron beam currents. Analysis of TEM photographs before and after annealing at 250 deg C indicate that the level of porosity decreases in the films by 1
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