Investigation of Hf $_{\text{0.5}}$ Zr $_{\text{0.5}}$ O $_{\text{2}}$ Ferroelectric Films at Low Thermal Budget (300 $^{\circ}$ C)

This study demonstrates annealing-free TiN/Hf
$_{\text{0.5}}$
Zr
$_{\text{0.5}}$
O
$_{\text{2}}$
(HZO)/TiN (MFM) ferroelectric (FE) capacitors using a low thermal budget process (300
$^{\circ}$
C), without post deposition annealing (PDA) or post metal annealing (PMA). The remnant polarizations (2
$\textit{P}_{\text{r}}$
) are 17.6 and 21.8
$\mu$
C/cm
$^{\text{2}}$
at the atomic layer deposition (ALD) temperatures (
$\textit{T}_{\text{dep}})$
of 280
$^{\circ}$
C and 300
$^{\circ}$
C, respectively. The in-plane stress induced by the distorted TiN electrode could be the origin contributing to the emergence of low-thermal-budget ferroelectricity. In addition, as the
$\textit{T}_{\text{dep}}$
decreases, there is a reduction in crystallinity, orthorhombic phase (o-phase) composition,
$\textit{P}_{\text{r}}$
, dielectric permittivity (
$\kappa)$
, and leakage current (J), leading to an enhancement in reliability. The demonstration of annealing-free ferroelectricity at temperatures as low as 300
$^{\circ}$
C is helpful for the back-end-of-line (BEOL) process and the reliability of FE nonvolatile memory.