Additive microfabrication of oxide structures by local electrodeposition and its application for fabrication of metallic actuators

Abstract

Achieving simplicity and efficiency has been an important objective for the development of new technologies and materials, and this thesis is similarly motivated. In the first chapter, a newly developed method based on local electrodeposition has been applied to additively microfabricating metallic or oxide structures. The method requires a minimum amount of electrolyte that allows the printing of an arbitrary 2D pattern in a single step, thus achieving both time and cost efficiency. As a demonstration of feasibility, a mixture of Cu2O and Cu is printed in different patterns with cathodic polarization of -2.5 V and nozzle scanning speed of 200 mm/min. The factors affecting the printing performance are analyzed, and methods to further improve the performance are proposed. In the following chapter, this newly developed technique is used to print patterns of NiOOH on Ni films, which aims at fabricating actuators that can execute complex motions. Stripes of NiOOH can be successfully printed with the printer within a short period of time, thanks to the high anodic polarization and prolonged reaction time due to repeated scanning. The actuator with the stripes indeed produces different motion as compared to that deposited with a uniform layer of NiOOH. Factors affecting the actuation performance are analyzed, and future work that would enable the actuator to be further improved and applied in various fields is discussed.