Modeling the breakdown spots in silicon dioxide films as point contacts

Experiments and simulations are combined to demonstrate that the hard dielectric breakdown of thin SiO2 films in polycrystaline silicon/oxide/semiconductor structures leads to the formation of conduction paths with atomic-size dimensions which behave as point contacts between the silicon electrodes. Depending on the area of the breakdown spots, the conduction properties of the breakdown paths are shown to be those of a classical Sharvin point contact or of a quantum point contact.