Electrode and Substrate Considerations in Discontinuous Thin Film Resistance

Abstract

In discontinuous films the difference between the electrostatic energy of a charge at rest on an island and a charge which has just been placed on an island by tunneling must be accounted for in a phenomonological explanation of the conduction mechanism. This energy difference can exceed the static electrostatic energy which is normally assumed to give rise to the thermally activated resistance experimentally observed in such films. It is also shown that the initial charge creation in discontinuous films may be more likely to arise from carrier injection at the electrodes than from island ionization in the middle of the film because of a lowered energy barrier height and an enhanced electric field in the vicinity of the electrodes. Under suitable conditions electrode injection will show a barrier energy lowering proportional to the square root of the applied field as is experimentally observed. Experimental results which may be indicative of electrode injection are presented.

Simultaneous fabrication of nanogap electrodes using field-emission-induced electromigration

“…10 In addition, it has been reported the investigation of voltage annealing effects of discontinuous films deposited between electrodes with varying separation. 11 Using these phenomena, we have reported wide ranging control of the tunnel resistance of nanogaps by a field-emission-induced electromigration technique called "activation." 12,13 Furthermore, we can control the electrical properties of the nanogaps by adjusting the magnitude of the preset current for the activation procedure and can thus easily obtain SETs using this activation procedure.…”