The thermal metastability of iron nitride was exploited to fabricate thin-film microstructures applicable to left-handed metamaterials. A granular thin film containing dispersed iron particles was prepared by post-annealing an rf-sputter-deposited Fe(0.5)Al(0.5)N thin film with a wurtzite-type structure in a nitrogen atmosphere at 450 degrees C. The obtained samples showed magnetic resonance in the microwave region. Laser direct writing was also applied in a nitrogen atmosphere to an rf-sputter-deposited Fe(0.7)Al(0.3)N thin film. 200 mu m-wide, 300 Omega cm iron metal lines were drawn in a host nitride film of approximately 2 k Omega cm. Combining and optimizing the above negative permeability and permittivity values should provide left-handed materials with a negative refractive index. (C) 2010 Elsevier Ltd. All rights reserved.