Electron currents through thick insulators by Schottky injection

This paper reports the measurement of an electron current through the offset gate of an MOS tetrode. This device has two stacked gates between the source and the drain. The control gate, located adjacent to the source, is deposited over a 1000 Å insulator. The offset gate is between the control gate and the drain and is deposited on top of a micron insulator. In the 1969 Circuits Conference in Philadelphia, H. G. Dill, et al, demonstrated that electrons could be injected over the, Schottky barrier between silicon and the offset gate insulator. They showed that injection followed by trapping at an oxide-nitride interface coUld be used to make an electrically alterable read-only memory.