Temperature dependent mechanical characterization of sputtered copper-silver thin film tensile specimens produced by photolithography
Viswanadh Gowtham Arigela, Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, GermanyTobias Oellers, Ruhr Universitat Bochum, Bochum, GermanyAlfred Ludwig, Ruhr Universitat Bochum, Bochum, GermanyChristoph Kirchlechner, Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, GermanyGerhard Dehm, Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany
The study of mechanical properties of materials at high temperatures at the microstructural length scale requires dedicated testing setups. A novel design with independent tip and sample heating is developed to characterize materials at high temperatures. This design is realized by modifying a displacement controlled room temperature micro straining rig (see Kirchlechner et al, Adv. Eng. Mat. 2011) with addition of two miniature hot stages, one of each carrying the sample and indenter tip. The sample reaches temperatures of > 600°C with two independent 50W diode laser systems. A special temperature referencing method is used for precise temperature measurements and the whole setup is placed inside a custom-made steel chamber, capable of attaining a vacuum of 10-6 mbar. Within the work, the application of this setup in characterizing copper, copper-silver thin film libraries produced by photolithography at temperatures ranging from ambient to 400°C are presented. The variation of these properties with variable annealing times are studied and they are presented along with the results from experiments conducted at room temperature after annealing in all of these systems. The effects of microstructure evolution leading to this enhancement is also discussed.