Temperature dependence of <i>I–V</i> characteristics of vacuum triodes from 24 to 300 K

Abstract

Collector and gate currents as a function of collector voltage have been measured for molybdenum Spindt emitters, for n-type monocrystalline, and for n-type polycrystalline silicon emitters in the temperature range from 24 to 300 K and at a pressure of 1×10−8 Torr. The devices were tested in an as-fabricated mode with a modest in situ bake of 100 °C. The silicon devices which were fabricated in two different laboratories using different processes showed very little temperature dependencies, whereas the molybdenum emitter exhibited an increase in work function with decreasing temperature. It is conjectured that adsorption/desorption events from the background gas onto the emitter tips are responsible for the observed temperature dependency.