A <inline-formula> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula>-Controller-Based System for Interfacing Selectorless RRAM Crossbar Arrays

Abstract

Selectorless crossbar arrays of resistive randomaccess memory (RRAM), also known as memristors, conduct large sneak currents during operation, which can significantly corrupt the accuracy of cross-point analog resistance (M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</sub> ) measurements. In order to mitigate this issue, we have designed, built, and tested a memristor characterization and testing (mCAT) instrument that forces redistribution of sneak currents within the crossbar array, dramatically increasing M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</sub> measurement accuracy. We calibrated the mCAT using a custom-made 32 × 32 discrete resistive crossbar array, and subsequently demonstrated its functionality on solid-state TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2-x</sub> RRAM arrays, on wafer and packaged, of the same size. Our platform can measure standalone M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</sub> in the range of 1 kΩ to 1 MΩ with <;1% error. For our custom resistive crossbar, 90% of devices of the same resistance range were measured with <;10% error. The platform's limitations have been quantified using large-scale nonideal crossbar simulations.