Significant Reliability Improvement by Inducing Dual Atomic-Thin Titanium Intercalation Layers in Hf0.5Zr0.5O2 Films

This work studies the ferroelectric Hf
$_{{0}.{5}}$
Zr0.5O2 (HZO) thin film with various designs of intercalation layers. Among the studied intercalation stacks, HZO films with dual
$\sim $
0.05 nm titanium layers (DL-Ti) present ultrahigh remanent polarization (
$2{P}_{{\text {r}}}\sim 57 \mu \text{C}$
/cm2), a low coercive field (
${E}_{{\text {c}}}\sim 1.1$
MV/cm), and a high breakdown field (
${E}_{{\text {BD}}}\sim 4.3$
MV/cm). Wherein, a rather low
${E}_{{\text {c}}}/{E}_{{\text {BD}}}$
of 27% can greatly benefit endurance property. In comparison to the standard HZO films, 3 orders better endurance (
$10^{{10}}$
cycles @3 MV/cm) has been achieved in DL-Ti HZO films, while only 3%
${P}_{{\text {r}}}$
degradation can be observed even after
$10^{{7}}$
cycles (@125 °C). Our results strongly indicate that atomic layer doping is an effective approach to engineer HZO-based devices with better performance and robust reliabilities.