Wake‐Up Mechanisms in Ferroelectric Lanthanum‐Doped Hf 0.5 Zr 0.5 O 2 Thin Films

Since the discovery of ferroelectricity in thin doped hafnium oxide layers, there is a rapidly growing interest in the implementation of this material into nonvolatile memory devices such as ferroelectric capacitors, transistors, or tunnel junctions. In most cases, a field‐cycling‐induced change in the remanent polarization is attributed to wake‐up and fatigue in ferroelectric HfO 2 devices. The lanthanum‐doped hafnium/zirconium mixed oxide system is of broad interest due to its high endurance stability and low crystallization temperature which is necessary for low thermal budget, back‐end of line devices. Herein, a detailed temperature‐dependent field‐cycling study is performed in a wide temperature range from liquid nitrogen to room temperature to separate field‐cycling‐induced charge movements from phase change effects. Results are expected to be relevant for similar doped HfO 2 ferroelectric layers.