Bipolar Resistive Switching in Junctions of Gallium Oxide and p-type Silicon

In this work, native GaO_<i>x</i> is positioned between bulk gallium and degenerately doped p-type silicon (p⁺-Si) to form Ga/GaO_<i>x</i>/SiO_<i>x</i>/p⁺-Si junctions. These junctions show memristive behavior, exhibiting large current-voltage hysteresis. When cycled between -2.5 and 2.5 V, an abrupt insulator-metal transition is observed that is reversible when the polarity is reversed. The ON/OFF ratio between the high and low resistive states in these junctions can reach values on the order of 10⁸ and retain the ON and OFF resistive states for up to 10⁵ s with an endurance exceeding 100 cycles. The presence of a nanoscale layer of gallium oxide is critical to achieving reversible resistive switching by formation and dissolution of the gallium filament across the switching layer.