DETERMINISTIC RESISTIVE SWITCHING CONTROL IN HfO2-BASED MEMORY DEVICES

R. ZAZPE; M. UNGUREANU; R. LLOPIS; F. GOLMAR; P. STOLIAR; F. CASANOVA; L. HUESO

Aachen

Conferencia; Frontiers in Electronic Materials: Correlation Effects and Memristive Phenomena; 2012

An intense research effort is currently focused on the development of the next generation of nonvolatile memory devices. Resistance random access memory (RRAM) has emerged as one of the most promising alternatives to current technologies due its inherent properties such as high density, simple structure, low power operation and scalability. RRAM operation is based on the reversible switching between two different resistance states triggered by an electric field or resistive switching (RS). In this work we study in detail a RS HfO2-based memory cell with a metal-insulator-metal (MIM) vertical structure in which the HfO2 was deposited by Atomic Layer Deposition (ALD). We carried out a statistic study on the effect of the HfO2 deposition process conditions on the resistive switching behavior. Different oxygen vacancies concentrations are induced depending on the ALD conditions and its effect on the metal/oxide barrier could explain the diverse RS performances observed. A further correlation found between the RS behavior and the pristine leakage currents lead us to propose an oxygen vacancy-based model for explaining the switching process.