Thin-Film Engineering of Mechanical Fragmentation Properties of Atomic-Layer-Deposited Metal Oxides
Mikko Ruoho,
Janne-Petteri Niemelä,
Carlos Guerra-Nunez,
Natalia Tarasiuk,
Georgina Robertson,
Aidan A. Taylor,
Xavier Maeder,
Czeslaw Kapusta,
Johann Michler,
Ivo Utke
Affiliations
Mikko Ruoho
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Janne-Petteri Niemelä
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Carlos Guerra-Nunez
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Natalia Tarasiuk
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Georgina Robertson
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Aidan A. Taylor
Materials Department, University of California, Santa Barbara, CA 93106, USA
Xavier Maeder
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Czeslaw Kapusta
AGH University of Science and Technology Krakow, Faculty of Physics and Applied Computer Science, Al.Mickiewicza 30, 30-059 Kraków, Poland
Johann Michler
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Ivo Utke
Empa–Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
Mechanical fracture properties were studied for the common atomic-layer-deposited Al2O3, ZnO, TiO2, ZrO2, and Y2O3 thin films, and selected multilayer combinations via uniaxial tensile testing and Weibull statistics. The crack onset strains and interfacial shear strains were studied, and for crack onset strain, TiO2/Al2O3 and ZrO2/Al2O3 bilayer films exhibited the highest values. The films adhered well to the polyimide carrier substrates, as delamination of the films was not observed. For Al2O3 films, higher deposition temperatures resulted in higher crack onset strain and cohesive strain values, which was explained by the temperature dependence of the residual strain. Doping Y2O3 with Al or nanolaminating it with Al2O3 enabled control over the crystal size of Y2O3, and provided us with means for improving the mechanical properties of the Y2O3 films. Tensile fracture toughness and fracture energy are reported for Al2O3 films grown at 135 °C, 155 °C, and 220 °C. We present thin-film engineering via multilayering and residual-strain control in order to tailor the mechanical properties of thin-film systems for applications requiring mechanical stretchability and flexibility.
