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Mechanical and electrical coupling at metal-insulator-metal nano-scale contacts



Doo-In Kim, Pradeep Namboodiri, Frank W. DelRio, Robert F. Cook


Mechanical and electrical coupling at nano-scale metallic contacts was investigated using a conducting-probe atomic force microscope (AFM). The current-voltage responses were non-Ohmic, symmetric about zero bias, with conductance values smaller than the quantum conductance limit, which indicate electron tunneling through an insulating layer. Using a self-consistent contact mechanics model and a parabolic tunneling model for thin insulating layers, we determined the contact area, barrier height, and barrier thickness as a function of applied contact load. The results suggest the presence of two insulating layers: an oxide layer on the AFM tip and an organic contaminant layer on the metallic surface.
Applied Physics Letters


atomic force microscope, electron tunneling, contact mechanics


Kim, D. , Namboodiri, P. , DelRio, F. and Cook, R. (2008), Mechanical and electrical coupling at metal-insulator-metal nano-scale contacts, Applied Physics Letters (Accessed April 14, 2024)
Created May 21, 2008, Updated October 12, 2021