Optically Induced Switching in Bistable Structures: Heavily Doped n⁺- Polysilicon - Tunnel Oxide Layer - n - Silicon

Abstract

The interest in metal-insulator-semiconductor (MIS) diode structures with the insulator layer thinner than 50 Å, when the conductivity of the layer can no longer be ignored, has arisen over 25 years ago and has been initially related to the mechanism of the current flow, particularly by tunneling. In recent years the interest in such structures with a partly conducting insulator, i.e., in metal-tunnel insulator-semiconductor (MTIS) structures has grown due to several factors. These factors include the following: the need to reduce the thickness of the gate insulator in silicon field-effect transistors so as to reduce the length of the channel to submicron dimensions in modern integrated circuits, the development of MIS transistors with a tunnel emitter, the feasibility of constructing highly efficient solar cells and photodetectors from MIS diodes, and the development of MIS switches and oscillators operating on the basis of the tunnel surface-barrier instability effect.