Decoupled switching dynamics and series resistance effects in Ti/HfO2 complementary resistive switching systems

Abstract

We investigate Ti/HfO2 complementary resistive switching (CRS) devices using a three-terminal configuration that enables direct measurement of the voltage across each memristor during operation. The results show that the apparent shifts in the global CRS voltage response, observed with increasing sweep amplitude, originate from a voltage-divider effect produced by internal series resistance. At the same time, the intrinsic switching voltages of each memristor remain constant at ≈0.4–0.5 V. By isolating the response of each memristor, we obtain direct access to the local voltage drops and precisely identify the switching events of each element. Series resistance plays a decisive role, strongly influencing operating conditions and energy efficiency. These insights provide a robust physical framework for CRS dynamics and practical guidelines for optimizing current and voltage control in logic-in-memory circuits and selector-less crossbar arrays.