Robust formation of ferroelectric HfO2 films by Y2O3 sub-monolayer lamination

Abstract

Abstract Process robustness of ferroelectric HfO2 films formed by dopant-laminated structure is investigated. Ferroelectric hysteresis obtained by the sub-monolayer Y2O3 laminated structure confirms that entire doping to the HfO2 films is not indispensable to stabilizing the ferroelectric phase. The Y-laminated HfO2 capacitors show robustness against the oxygen plasma exposure time, in contrast to the positive hysteresis shift for uniformly doped HfO2 ones. The number of switching cycles was increased, presumably owing to the reduction of oxygen vacancies associated with the incorporated dopants. Moreover, the leakage current showed a reduction with a higher breakdown voltage.