Ruoho Mikko, Niemelä Janne-Petteri, Guerra-Nunez Carlos, Tarasiuk Natalia, Robertson Georgina, Taylor Aidan A, Maeder Xavier, Kapusta Czeslaw, Michler Johann, Utke Ivo
Empa-Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland.
Materials Department, University of California, Santa Barbara, CA 93106, USA.
Nanomaterials (Basel). 2020 Mar 19;10(3):558. doi: 10.3390/nano10030558.
Mechanical fracture properties were studied for the common atomic-layer-deposited AlO, ZnO, TiO, ZrO, and YO 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, TiO/AlO and ZrO/AlO bilayer films exhibited the highest values. The films adhered well to the polyimide carrier substrates, as delamination of the films was not observed. For AlO 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 YO with Al or nanolaminating it with AlO enabled control over the crystal size of YO, and provided us with means for improving the mechanical properties of the YO films. Tensile fracture toughness and fracture energy are reported for AlO 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.
通过单轴拉伸试验和威布尔统计方法，研究了常见的原子层沉积AlO、ZnO、TiO、ZrO和YO薄膜以及选定的多层组合的机械断裂性能。研究了裂纹起始应变和界面剪切应变，对于裂纹起始应变，TiO/AlO和ZrO/AlO双层薄膜表现出最高值。薄膜与聚酰亚胺载体基板粘附良好，未观察到薄膜分层现象。对于AlO薄膜，较高的沉积温度导致较高的裂纹起始应变和内聚应变值，这可以通过残余应变的温度依赖性来解释。用Al掺杂YO或用AlO对其进行纳米层压能够控制YO的晶体尺寸，并为我们提供改善YO薄膜机械性能的方法。报告了在135°C、155°C和220°C下生长的AlO薄膜的拉伸断裂韧性和断裂能。我们通过多层结构和残余应变控制来进行薄膜工程，以便为需要机械拉伸性和柔韧性的应用定制薄膜系统的机械性能。
