M. Bendahan et al., CONTROL COMPOSITION STUDY OF SPUTTERED NI-TI SHAPE-MEMORY ALLOY FILM, Materials science & engineering. B, Solid-state materials for advanced technology, 34(2-3), 1995, pp. 112-115
Since the transition temperature of the shape memory effect in NixTi1-
x films depends on the composition of the layer, it is indispensable t
o have an accurate control on their composition. We are now able to co
ntrol in situ the composition of r.f. sputtered Ni-Ti films in the who
le domain of shape memory effect (0.476 < x < 0.531). by varying the p
roduct of sputtering gas pressure P and target-to-substrate distance d
. Pressure measurements are found to give a good sensitivity for the c
ontrol of Ti-rich layers, while the optical emission spectroscopy of t
he sputtering plasma gives better sensitivity for Ni-rich layers.