Reduced annealing temperature for ferroelectric HZO on InAs with enhanced polarization
Anton E. O. Persson, Robin Athle, Pontus Littow, Karl‐Magnus Persson, Johannes Svensson, Mattias Borg, Lars‐Erik Wernersson
Abstract
Deposition, annealing, and integration of ferroelectric HfxZr1−xO2 (HZO) thin films on the high-mobility semiconductor InAs using atomic layer deposition are investigated. Electrical characterization reveals that the HZO films on InAs exhibit an enhanced remanent polarization compared to films formed on a reference TiN substrate, exceeding 20 μC/cm2 even down to an annealing temperature of 370 °C. For device applications, the thermal processes required to form the ferroelectric HZO phase must not degrade the high-κ/InAs interface. We find by evaluation of the capacitance–voltage characteristics that the electrical properties of the high-κ/InAs are not significantly degraded by the annealing process, and high-resolution transmission electron microscopy verifies a maintained sharp high-κ/InAs interface.