FMR linewidths of YIG films fabricated by ex situ post-annealing of amorphous films deposited by rf magnetron sputtering

FMR linewidths of Y3Fe5O12 (YIG) films fabricated by ex situ post-annealing of amorphous films deposited by radio frequency magnetron sputtering are reported. Amorphous YIG films were deposited on both thermally oxidized Si(100) and Gd3Ga5O12 (GGG) (111) substrates and subsequently crystallized by ex situ post-annealing (600-900 degrees C) in two different oxygen atmospheres (air and 500 ppm O-2). The compositions of as-deposited films were very sensitive to the oxygen partial pressure (P-o2) of the sputtering gas. During the post-annealing process, crystalline YIG phase started to grow upward on the substrates. High-quality YIG films showing narrow FMR linewidths (Delta H) of 5.3 and 70 Oe for GGG and thermally oxidized Si substrates, respectively, could be grown from the amorphous films deposited in pure Ar gas, composed of the cation ratio (Y: Fe = 3.04:4.96) close to the stoichiometric YIG. A reduced oxygen annealing atmosphere was found more effective than air for obtaining narrower FMR linewidths. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.