The Impact of X-Ray and Proton Irradiation on ${\rm HfO}_2/{\rm Hf}$-Based Bipolar Resistive Memories

Abstract

This paper investigates total-ionizing dose effects on the electrical characteristics of HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /Hf-based bipolar resistive-random-access-memory (RRAM) devices. 10-keV x-ray irradiation does not cause significant changes in resistance at levels up to 7 Mrad( SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ). Excess carriers generated by x-ray irradiation in the HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> layer recombine or are trapped at defect sites in the HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> layer or at interfaces between layers. They have no effect, however, on the conductive path of the RRAM devices. 1.8 MeV proton irradiation causes resistance degradation through simultaneous introduction of oxygen vacancies and displacement damage. TRIM simulations are used to explain the physical mechanisms of the radiation-induced damage. The devices are promising for radiation-hardened memory applications.