Electrical hysteresis of ultrathin silicon oxides induced by heavy boron doping

摘要

We have fabricated a resistive memory device made of the ultrathin (1.6-3.6 nm) layer of silicon oxide, for which the electrical hysteresis is hardly induced via the conventional electroforming process or field-driven structural modification because non-dissipative quantum tunneling across it hampers this process. We show that such thin silicon oxide comes to exhibit the hysteretic behavior successfully when a large amount of boron atoms are incorporated into it: a typical ratio of high-to-low resistance is as high as 300 and maintained up to the set/reset cycles of 50 000, and the projected retention time is longer than a couple of months. We also propose an electronic model for its hysteretic mechanism where the charge trapping into the boron-induced defects in silicon oxide and the alteration of its energy band near the interfacial region play the active roles. Published by AIP Publishing.