Effect of H2O and O3 as the oxygen sources on the atomic layer deposition of ferroelectric Hf0.5Zr0.5O2 film

Abstract

In this paper, the ferroelectric (FE) properties of 20-nm-thick Hf0.5Zr0.5O2 films deposited by an atomic layer deposition technique by using O3 or H2O as an oxygen source were studied. For both oxygen source, the Hf0.5Zr0.5O2 films exhibited the formation of a non-centrosymmetric orthorhombic phase, which was responsible for the FE behavior. However, it was shown that the H2O-based Hf0.5Zr0.5O2 films were more unsuitable for hydrogen from H2O than the O3-based Hf0.5Zr0.5O2 films, which reduced the FE polarization and increased the leakage behavior. The results indicated that the use of O3 as an oxygen source in the ALD process has potential for the fabrication of FE Hf0.5Zr0.5O2 films for next generation memory applications.