Bistable Actuation Based on TiNiHf/Si Shape Memory Nanoactuators
Conference: MikroSystemTechnik Kongress 2023 - Kongress
10/23/2023 - 10/25/2023 at Dresden, Deutschland
Proceedings: MikroSystemTechnik Kongress 2023
Pages: 5Language: englishTyp: PDF
Authors:
Li, Zixiong; Arivanandhan, Gowtham; Kohl, Manfred (Institute of Microstructure Technology, Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany)
Curtis, Sabrina M. (Institute for Materials Science, Kiel University (CAU), Kiel, Germany & Department of Materials Science and Engineering, University of Maryland, USA)
Quandt, Eckhard (Institute for Materials Science, Kiel University (CAU), Kiel, Germany)
Abstract:
We present the design and analytical model of a bistable nanoactuator consisting of a PMMA/TiNiHf/Si trimorph layer composite, in which the layer of shape memory alloy TiNiHf shows a martensitic phase transformation with wide hysteresis in the temperature range of 50 - 140 °C, while the PMMA layer undergoes a glass transition at 105 °C. We demon-strate that the thickness of the TiNiHf layer can be adjusted down to a critical thickness of 220 nm using a Si substrate with SiO2 buffer layer without affecting its phase transformation temperatures, which enables the design of ultra-compact bistable actuator devices. The presented model characterizes the bistable actuation stroke as a function of PMMA layer thickness at room temperature. The obtained optimal layer thicknesses allow for the development of a process flow for nanofabrication of the trilayer composite.