Abstract: A semiconducting diode utilizing the transit time of electrical charge carriers in a semiconductor medium, having an input structure formed by a matrix of micropoints, said matrix consisting of a plurality of microscopic contacts separated by an insulating layer. The diameter of each contact is of the order of 0.5 to 5 micrometers, the distance between the closest contacts being of the order of 0.5 to 15 micrometers. The contacts are made of metal or of an alloy of low resistivity or of a semiconductor material generally doped more heavily than the layer of the semiconductor lying under the microscopic contact. The result of such a structure is an increase in efficiency attributable to the reduction in avalanche voltage or to a better injection by tunnel effect.

Abstract: A method for virtually eliminating contact resistances in particular at very high frequency, for instance in the case of source and drain contacts of a field effect transistor. The method consists in creating a matrix of depressions or "dishes", for example 1 to 6 microns in diameter, separated by intervals of some few microns. In a first step, windows are opened in an insulating layer by an etching operation. In a second step, by ion machining, angular profiles are carved in the bottom of the dishes for promoting tunnel effect. In a last step a metal layer is deposited and enshrouds the matrix.