• Schell, Norbert
• Beckers, Manfred
• Mahesh, Karimbi K.
• Reuther, Helfried
• Silva, Rui J. C.
• Santos Martins, Rui Miguel
• Fernandes, Francisco Manuel Braz
• Mücklich, Arndt

Abstract

<p>The preferential orientation of Ni-Ti thin films is a crucial factor in determining the shape memory behaviour. The texture has a strong influence on the extent of the strain recovery. The relationship between structure and deposition parameters is of extreme importance for future device applications. Our approach is in-situ x-ray diffraction during deposition carried out in a process chamber installed at a synchrotron radiation beamline. Near-equiatomic films were co-sputtered from Ni-Ti and Ti targets. Substrate type and bias voltage play an important role for the preferred orientation. On naturally oxidized Si(100) substrates the Ni-Ti B2 phase starts by stacking onto (hOO) planes and then changes to &lt;110&gt; fibre texture with increasing film thickness. For thermally oxidized Si(100) substrates, this cross-over is only observed when a substrate bias voltage is applied. The experiments were supplemented by ex-situ transmission electron microscopy and Auger electron spectroscopy allowing an additional deeper insight into the film/substrate interface.</p>

Topics

• Deposition
• impedance spectroscopy
• phase
• x-ray diffraction
• experiment
• thin film
• transmission electron microscopy
• texture
• Auger electron spectroscopy