Conduction and switching phenomena in thermally grown silicon dioxide films†

Two switching mechanisms have been observed in M.O.S. devices employing thermally grown silicon dioxide films, 0.1 µ and 0-15 µ thick. One mechanism resulted in a switch from a low conductance V-I characteristic to a high conductance characteristic; a return to zero applied volts was necessary to reverse the switch. With the second mechanism, forward and reverse transitions occurred at the same points in the V-I characteristic. Oscillations characterized by an exponential rise and sharp fall were also observed and found to be associated with the transition points on the V-I relationships. The frequency of these oscillations was approximately 1 MHZ, and varied as the inverse of M.O.S. capacitor area.