Nanowerk December 10, 2019
The emergence of ferroelectricity in nanometer-thick films of doped hafnium oxide (HfO2) makes this material a promising candidate for use in Si-compatible non-volatile memory devices. To make ferroelectric capacitors usable as memory cells, their remnant polarization has to be maximized. An international team of researchers (Germany, Russia, USA – North Carolina State University, University of Nebraska) developed a new methodology to experimentally quantify the polarization-dependent potential profile across a few-nanometer-thick ferroelectric Hf0.5Zr0.5O2 thin films. They found the electric potential profile across the Hf0.5Zr0.5O2 layer to be non-linear and changes with in-situ polarization switching. The non-linear potential behavior is because of defects at both interfaces, and their charge state modulated by the ferroelectric polarization. The results provide an important insight into the intrinsic electronic properties of HfO2 based ferroelectric capacitors and are essential for engineering memory devices…read more. TECHNICAL ARTICLE