Optical emission spectroscopy study of magnetron assisted Ni-Ti dc sputtering

Ni-Ti thin films where the R-phase transformation occurs between 55ºC and 30ºC, the peak temperature being 40ºC, have been produced. These thin films have been grown using a magnetron assisted system of dc sputtering, with a Glow-Discharge Optical Emission Spectroscopy device. The OES technique has been used to investigate the spatial distribution of sputtered atoms from the cathode to the substrate in different operating conditions: Argon pressure of 5 and 9x10 - 4 Torr, without polarization and with - 60 V bias. Structural characterization of the thin films has been made by XRD and the transformation temperatures associated to the shape memory effect have been determined by DSC. A discussion of the optimization of the processing parameters (Argon pressure and polarization) is then presented.