The crystallization behavior of nominal-composition GeSb2Te4 films prepared
by rf-magnetron sputtering are examined. The crystal structures of the as-
sputtered and the annealed films at different annealing temperatures are id
entified by the X-ray diffraction (XRD) method. Two phase transformations o
ccur in the conventional slow heating process when the as-sputtered film is
heat-treated from the ambient temperature to its melting point. However, o
nly the amorphous to face-centered cubic (FCC) transformation is allowed wh
en laser annealing with a 10(11)degrees C/min heating rate is applied to he
at the films. Consequently we predict that the meta stable FCC phase, inste
ad of the hexagonal closed-packed (HCP) phase, is the dominant crystalline
phase in the GeSb2Te4 phase-change recording medium.