Resistive switching in memristors based on Ag/Ge/Si heterostructures

Ag/Ge/Si heterostructures with threading dislocations in Ge layer can exhibit resistive switching (RS) in two regimes: (i) bipolar and (ii) volatile unipolar. In both regimes, these structures possess stable states with the ratio of currents in the low-resistance state (LRS) and high-resistance state (HRS) within 1.5–2.7. The volatile unipolar switching can be determined by capturing charge carriers on deep levels related to misfit dislocations at the Ge/Si interface, whereas the bipolar switching is related to the drift of Ag$^+$ ions via threading dislocations.