Current switching in bistable structures: Heavily doped n +-polysilicon-tunnel-oxide layer-n-silicon

Abstract

Switching from a state with a steady-state nonequilibrium depletion and low current into the “on” state with a high current and low voltage drop on the structure is observed in highly doped n+-polysilicon-tunnel-oxide-n-silicon structures. The structures were prepared on n-silicon substrates with a resistivity of 25 Ω·cm. A structure with an oxide thickness of 23 A can be switched on both by a radiation pulse with small reverse bias on the structure (50 V) and under dark conditions by increasing the reverse bias to 250–300 V. In the “on” state Auger carrier production is the internal source of minority carriers that is required for compensating tunnel leakage of holes into the n+-polysilicon and for maintaining a quasiequilibrium inversion layer of holes at the n-Si-SiO2 boundary.