Composition and temperature dependent remanent polarization and coercive field in wurtzite AlScN ferroelectric memory materials

We investigate the Sc dependence and thermal sensitivity of Al1−xScxN with the aid of Landau–Devonshire free energy recently proposed for its wurtzite ferroelectric phase. In particular, we calculate compositional and temperature dependences of the remanent polarization and the coercive field. Because the polarization is strong, surface fluctuations of the polarization are expected; we examine the nature of these fluctuations. Strong correlation is expected as the ferroelectric phase gives way to the paraelectric phase.