Nanoelectromechanical tunneling switches based on self-assembled molecular layers

Publication Type:



Micro Electro Mechanical Systems (MEMS), 2014 IEEE 27th International Conference on ,, p.1103-1106 (2014)


2014, assembling, Electrodes, electromechanical modulation, electrostatic compression, Films, fluorinated decanethiol layer, Force, Gold, molecular switching gap, nanoelectromechanical devices, nanoelectromechanical tunneling switches, self-assembled molecular layers, Self-assembly, surface adhesive forces, switches, Tunneling, tunneling current


We propose nanoelectromechanical (NEM) switches that operate via electromechanical modulation of tunneling current through
several-nanometer-thick switching gaps. In such a device, direct contact
between electrodes is avoided by utilizing self-assembled molecular layers
to define the switching gap. Electrostatic compression of the molecular
layer reduces the tunneling gap leading to an exponential increase in the
tunneling current, turning on the switch. With removal of an applied
voltage, the compressed layer provides the elastic restoring force
necessary to overcome the surface adhesive forces, turning off the switch.
Thus, the proposed tunneling NEM switch may enable low-voltage operation
while simultaneously mitigating device failure due to stiction. This
principle is experimentally investigated using a prototype two-terminal
tunneling NEM switch with a switching gap formed by a fluorinated
decanethiol layer. In this device, the presence of the molecular film
promotes repeatable switching. A comparison of the switch operation with a
theoretical model indicates electrostatic compression of the molecular
switching gap.