Growth of sputter-deposited Ni-Ti thin films: Effect of a SiO2 buffer layer |
| |
Authors: | RMS Martins N Schell M Beckers KK Mahesh RJC Silva FMB Fernandes |
| |
Institution: | (1) Institute of Ion Beam Physics and Materials Research, Forschungszentrum Rossendorf, P.O. Box 510119, 01314 Dresden, Germany;(2) CENIMAT, Campus da FCT/UNL, 2829-516 Monte de Caparica, Portugal |
| |
Abstract: | In-situ X-ray diffraction (XRD) during the growth of Ni-Ti thin films was chosen in order to investigate their texture development using a deposition chamber installed at a synchrotron radiation beamline. Near-equiatomic films were co-sputtered from Ni-Ti and Ti targets. The texture evolution during deposition is clearly affected by the substrate type and the ion bombardment of the growing film. On naturally oxidized Si(100) substrates, the Ni-Ti B2 phase starts by stacking onto (h00) planes, and as the thickness increases evolves into a (110) fibre texture. For the deposition on thermally oxidized Si(100) substrates, this pronounced cross-over is only observed when a substrate bias voltage (-45 V) is applied. The oxide layer plays an important role on the development of the (100) orientation of the B2 phase during deposition on heated substrates (≈470 °C). If this layer is not thick enough (naturally oxidized Si substrate) or if a bias voltage is applied, a cross-over and further development of the (110) fibre texture is observed, which is considered as an orientation that minimizes surface energies. Electrical resistivity measurements showed different behaviour during phase transformation for the Ni-Ti film deposited on thermally oxidized Si without bias and those on thermally oxidized Si(100) with bias and on naturally oxidized Si(100) without bias. This is related to stresses resultant from the fact that the Ni-Ti films are attached to the substrates as well as with the existence of distinct textures. PACS 81.15.Cd; 61.10.Nz; 68.55.Jk |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|