Amorphous ITZO-Based Selector Device for Memristor Crossbar Array

In the era of digital transformation, a memristor and memristive circuit can provide an advanced computer architecture that efficiently processes a vast quantity of data. With the unique characteristic of memristor, a memristive crossbar array has been utilized for realization of nonvolatile memory, logic-in-memory circuit, and neuromorphic system. However, the crossbar array architecture suffers from leakage of current, known as the sneak current, which causes a cross-talk interference problem between adjacent memristor devices, leading to an unavoidable operational error and high power consumption. Here, we present an amorphous In-Sn-Zn-O (a-ITZO) oxide semiconductor-based selector device to address the sneak current issue. The a-ITZO-selector device is realized with the back-to-back Schottky diode with nonlinear current-voltage (I-V) characteristics. Its nonlinearity is dependent on the oxygen plasma treatment process which can suppress the surface electron accumulation layer arising on the a-ITZO surface. The a-ITZO-selector device shows reliable characteristics against electrical stress and high temperature. In addition, the selector device allows for a stable read margin over 1 Mbit of memristor crossbar array. The findings may offer a feasible solution for the development of a high-density memristor crossbar array.

Automated summary

In the era of digital transformation, a memristor and memristive circuit have been utilized for advanced computer architecture. However, the crossbar array architecture suffers from current leakage, known as the sneak current, resulting in operational errors and high power consumption. To address this issue, we propose an amorphous In-Sn-Zn-O (a-ITZO) oxide semiconductor-based selector device with back-to-back Schottky diodes and nonlinear I-V characteristics, which suppresses surface electron accumulation and shows reliable characteristics against electrical stress and high temperature. The findings present a feasible solution for the development of a high-density memristor crossbar array.