Cryogenic Characteristics of HfOx-based Resistive Switching Memory

Abstract

HfOx-based resistive random access memories (RRAMs) have attracted much attention for future non-volatile memory (NVM) to realize a neuromorphic system. They demonstrated successful CMOS compatibility, good stability, and low power consumption. At room temperature and cryogenic temperature (77 K or 4 K), HfOx-based RRAM exhibited their potential for low power memory devices. In this thesis, Pt/Ti/HfOx/Pt structure HfOx-based RRAM for operation at cryogenic temperature was fabricated and analyzed its performance and mechanisms. To get stability under vacuum environment, HfOx deposition condition was adjusted and Titanium layer’s thickness which has an role as top electrode and oxygen reservoir layer to lower the operating energy consumption. By control the device structure, stable DC I-V characteristics from 300 K to 60 K were secured, and at 2.2 K resistive switching characteristics were observed. Through this work, understanding of RRAM characteristics at cryogenic temperature was achieved, which can be used for cryogenic electronics.