Thermionic emission from negative electron affinity silicon

Abstract
Thermionic emission from negative electron affinity surfaces on silicon has been studied. The value is dependent on the state of activation of the surface, and dark currents in the range 10−11−10−13 A/cm2 may be obtained. These values agree with those measured on sealed−off tubes. The dark current is thought to originate from surface states acting as traps for the generation of electrons. The density of surface states is estimated from the measurement of the variation of dark current during oxygenation. Field enhancement of dark current and photoemission has been observed.