Fabrication and analysis of a silicon tip avalanche cathode

As an attempt to develop a cathode with low operation voltage for the vacuum microelectronic devices, a new cathode-silicon tip avalanche cathode (STAC) has been fabricated and analyzed. STAC is a silicon field emitter with a shallow n+-p+ junction formed on the tip. The emission characteristics of the fabricated STAC show that the gate voltage at which the emission initiates is considerably lowered and the gate voltage required to produce a desired emission current is reduced. These characteristics of STAC result from the emission of the hot electrons generated and accelerated by the avalanche breakdown in the n+-p+ junction on the tip. However, a large current is needed for the avalanche breakdown and this results in low emission efficiency. A simple analysis is presented to explain the measured emission characteristics of the fabricated STAC.