Micro-patterning of metallic electrodes for dielectric elastomer actuators

• Main Author: Sim, Thiam Ling.
• Other Authors: School of Mechanical and Aerospace Engineering
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Manufacturing
• Online Access: http://hdl.handle.net/10356/16199
• Institution: Nanyang Technological University

This project aims to develop reliable compliant electrodes by patterning metallic thin film. The metallic electrode is formed in a pattern which allows lateral flexibility in order allow lateral stretching of the dielectric actuation. The designed patterns electrode on elastomer is formed by chemical etching and lithography. The metallic electrodes on elastomer are to be tested to ensure the mechanical integrity. Methods of metal deposition are investigated in this project. This work has attempted e-beam evaporation and thermal evaporation for metal deposition, and application of ultra-thin copper foil on soft dielectric elastomer like 3M VHB and PDMS. Finally, copper foil was chosen as the electrode material due to its faster and easier handling, and lower cost. In addition, it has the highest electrical conductivity among all. Fabrication of the dielectric elastomer actuator is introduced. 3M VHB 9473 tape and copper foil were selected as the dielectric layer and electrode. Dry film negative photoresist, ETERTEC HP-3410 was used to form the patterned masking on the substrate of copper foil. Meander pattern is designed for compliant electrodes in this project. Meander pattern is able to concentrate the elongation of the electrode in one direction. Finally, high-voltage actuation testing was conducted. The high-voltage testing shows plain electrodes of copper foil restrain elastomer layer and do not allow a planar expansion. On the other hand, meandered pattern electrodes (a design codenamed as S100-C100-G100) of copper foil show an expansion in width by 2.58%. A silver grease electrodes specimen also had been tested and result 6.71% of expansion in area at the same voltage.