Tunnel emission of electrons in photo-field detectors and in an Auger transistor in very strong electric fields

The effect of a strong electric field [(5-7) x 10(7) V cm(-1)] on the electron emission from a semiconductor to vacuum in photo-field detectors and in MIS structures with a tunnel-transparent insulator layer (Al-SiO2-n-Si Auger transistor) has been studied. It is shown for the first time that the existence of deep self-consistent quantum wells on the semiconductor surface in a strong electric field provides a possibility of controlling the energy of fast electrons responsible for the impact ionization near the base of the Auger transistor and changes the photosensitivity of narrow-gap photo-field cathodes in the IR spectral range due to the formation of a transistor structure at the semiconductor-vacuum interface. It is also demonstrated that, both in photo-field detectors and in tunnel Al-SiO2-n-Si transistor structures, only the electron tunnel current should be taken into account and the hole current, disregarded. The reason for this is that only the electron current exists in vacuum, and the tunneling of holes in Al-SiO2-n-Si from the semiconductor into the metal is unlikely because of the large hole effective mass in the valence band of SiO2. (C) 2003 MAIK "Nauka/Interperiodica".