The influence of deposition parameters on Ti/Pt film growth by confocal sputtering and the temperature dependent resistance behavior using SiOx and Al2O3 substrates

• DOI: 10.1016/j.apsusc.2014.05.203
• Publication Date: 2014-06-02T20:16:08Z
• Authors: G. Schmidl; J. Dellith; E. Kessler; U. Schinkel
• Keywords: Temperature coefficient

Abstract This paper presents the influence of sputtering power and pressure on microstructural growth and morphology of Ti/Pt films and their electrical properties for possible applications in thin film thermal electrical devices. For these applications a high temperature coefficient of resistance near to that of the bulk material is aspired to. Films deposited by a confocal sputtering arrangement showed at a high Ar pressure of 8 Pa columnar growth and a rough surface, contrary to films produced at 0.5 Pa. An increase in pressure and a decrease in power resulted in a higher electrical conductivity and in a higher temperature coefficient of resistance (TCR). This electrical behavior correlates to the film's micro-structure. Furthermore, the influence of two different substrate materials such as thermally oxidized Si and Al 2 O 3 ceramics on the electrical properties of the films and on the resulting crystalline film growing is presented. Ti/Pt films deposited on oxidized (1 0 0)-orientated Si showed a textured film growth with a preferred Pt(1 1 1) peak contrary to the deposition on Al 2 O 3 substrates. Films deposited on Al 2 O 3 substrates also have a preferred (1 1 1) peak, but a polycrystalline structure. On the basis of these structural and crystalline investigations we want to discuss the resistivity and TCR behavior after the annealing processes.