Impact of Molybdenum Oxide Electrode on the Ferroelectricity of Doped-Hafnia Oxide Capacitors

In this article, we investigate the role of MoO
_x
oxide electrodes on the ferroelectric properties of hafnium zirconium oxide (HZO) capacitors. The MoO
_x
oxide electrodes were deposited under different oxygen partial pressure ratios (
$\text{O}_{\text {ppr}}$
: 0%, 5%, 10%, and 15%) during the sputtering process. The remnant polarization (
${P}_{r}$
) of the HZO capacitors with MoO
_x
electrodes (18.9
$\mu \text{C}$
/cm
²
for 10%
$\text{O}_{\text {ppr}}$
) are improved higher than that of the TiN electrode (14.9
$\mu \text{C}$
/cm
²
) by 27%. In addition, the HZO films with MoO
_x
electrodes have smaller leakage current and larger breakdown electric field (
${E}_{\text {BD}}$
). Based on the polarization reversal theory, the interfacial capacitance (
${C}_{i}$
) and coercive field (
${E}_{c}$
) were calculated in the case of the devices with MoO
_x
electrodes, indicating that the MoO
_x
electrode can minimize the thickness of the non-ferroelectric dead layer at the bottom interface. These results are expected to provide a new way out to optimize the interface quality and ferroelectricity in HZO-based capacitors and ferroelectric memory.