High density data storage systems utilizing the atomic force microscopy have been developed for a next-generation storage technology. We have reported new fabrication methods of micro tips with contact shadow mask process formed on a metal-layered cantilever for bi-directional driving. The cantilever was designed to deflect upward by the electro-thermal Joule heat and downward by the electrostatic force; this could be done by changing the driving sources. Electro thermal driving is utilized to write data bits while electrostatic driving is to equalize the heights of the arrayed tips and / or to read data bit by the resonance vibration. We chose aluminum (Al) as sacrificial layer which was etched fast in the etchant, which did not etch cantilever body metals. The micro tips on the cantilever should not be etched during the releasing step. In this paper, we propose a consistent combination of materials of copper (Cu) for a good candidate for tip formation and aluminum for the sacrificial layer. The height of micro tips was about 2-3 um, and the radius of the apex was about 100 nm at minimum. The bi-directional actuator with a micro tip could be used to develop the AFM-based data storage.
Journal: TechConnect Briefs
Volume: 3, Nanotechnology 2008: Microsystems, Photonics, Sensors, Fluidics, Modeling, and Simulation – Technical Proceedings of the 2008 NSTI Nanotechnology Conference and Trade Show, Volume 3
Published: June 1, 2008
Pages: 446 - 449
Industry sector: Sensors, MEMS, Electronics
Topics: MEMS & NEMS Devices, Modeling & Applications