Structure and magnetic properties of CoFe2O4 nanocrystal thin films prepared by sol-gel method

Thin films of CoFe2O4 spinel ferrite were prepared on silicon (100) substrates at low temperature by means of a modified polyvinyl alcohol processing, and the structure and magnetic properties as a function of the only one varied calcination temperature were investigated in detail and optimized. The CoFe2O4 ferrite films had a single phase spinet structure and were well-crystallized at temperature above 600 degrees C, which is much lower than the required temperature in the traditional ceramic method (about 1000 degrees C). The films annealed at and above 500 degrees C for 1h showed the grain sizes between 9 and 40 nm, and exhibited high coercivities and high saturation magnetization. Co-ferrite films prepared by sol-gel method and annealed at 700 degrees C had excellent potential for important technological applications, such as information storage and magnetooptical devices.