Interplay of Switching Characteristics, Cycling Endurance and Multilevel Retention of Ferroelectric Capacitor
Jae Hur, Panni Wang, Zheng Wang, Gihun Choe, Nujhat Tasneem, Asif Islam Khan, Shimeng Yu
Abstract
Recent research has extensively investigated the ferroelectric Hf <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub> Zr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (HZO) thin film as a key enabler for emerging non-volatile memory (eNVM) and synaptic device for neuro-inspired computing. However, the reliability of HZO is not systematically characterized yet. For example, 1) post-cycling retention is rarely reported, 2) intermediate state retention is largely unexplored; 3) activation energy (E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a</sub> ) of the retention degradation with respect to the device failure time is unrevealed. Herein, we experimentally characterized 10 nm-thick plasma-enhanced atomic-layer-deposited (PEALD) HZO capacitors at the pristine, woken-up and fatigued states. The interplay of polarization switching speed, pulse cycling and multilevel retention is explored under variables such as device size and electric field. Woken-up state is found to be the most vulnerable to retention degradation with approximately E <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a</sub> =0.37 eV extracted.