Controlled fabrication of nanoscale gaps using stiction

Publication Type:

Miscellaneous

Source:

Micro Electro Mechanical Systems (MEMS), 2015 28th IEEE International Conference on , ieeexplore.ieee.org, p.85-88 (2015)

Keywords:

2015, Adhesives, cantilever deflection, cantilevers, capillary forces, common failure mode, device design, Electrodes, failure analysis, Gold, lateral motion, Lithography, M/NEMS, micro/nano electromechanical systems, microelectrodes, microfabrication, micromechanical devices, molecular devices, nanofabrication, nanometer-thin gaps, Nanoscale devices, nanoscale force control, nanoscale gaps controlled fabrication, permanent adhesion, Self-assembly, single lithography step, stationary electrodes, stiction, surface treatment

Abstract:

Utilizing stiction, a common failure mode in micro/nano electromechanical systems (M/NEMS), we propose a method for the controlled fabrication of
nanometer-thin gaps between electrodes. In this approach, a single
lithography step is used to pattern cantilevers that undergo lateral
motion towards opposing stationary electrodes separated by a defined gap.
Upon wet developing of the pattern, capillary forces induce cantilever
deflection and collapse leading to permanent adhesion between the tip and
an opposing support structure. The deflection consequently reduces the
separation gap between the cantilever and the electrodes neighboring the
point of stiction to dimensions smaller than originally patterned. Through
nanoscale force control achieved by altering device design, we demonstrate
the fabrication of nanogaps having controlled widths smaller than 15 nm.
We further discuss optimization of these nanoscale gaps for applications
in NEM and molecular devices.