Biblio

Recently, dielectric/ferroelectric (DE/FE) bilayer systems have been extensively investigated for achieving high remanent polarization in Hf0.5Zr0.5O2(HZO) based MFM capacitors. Herein, we report significant enhancement in the ferroelectric property of HZO capacitors by incorporating Ta2O5as the dielectric seed layer. Thickness of the Ta2O5layer was incorporated at both top and bottom of the HZO films and the thickness of the seed layer was varied from 10 to 50 Å. When the Ta2O5dielectric films were inserted at the top, the highest remanent polarization 16.83 μC/cm2 was observed in case of 20 Å films as compared to that of 13.21 μC/cm2 of the reference HZO device. Similarly, for bottom Ta2O5dielectric films, the highest remanent polarization 15.24 μC/cm2 was observed in case of 20 Å films. When we compared both the stacks, the best result was observed in case of top Ta2O5. The coercive field (Ec) was also found to be nearly same with the HZO based device despite the incorporation of the dielectric layer. The enhanced ferroelectricity of these devices can be used in memory devices, FeFETs, FTJ and sensors applications.

In this letter, ferroelectric memory performance of TiN/Y-doped-HfO2 (HYO)/TiN capacitors is investigated under proton radiation with 3-MeV energy and different fluence (5e13, 1e14, 5e14, and 1e15 ions/cm2). X-ray diffraction patterns confirm that the orthorhombic phase Pbc21 of HYOfilm has no obvious change after proton radiation. Electrical characterization results demonstrate slight variations of the permittivity and ferroelectric hysteresis loop after proton radiation. The remanent polarization (2Pr) of the capacitor decreases with increasing proton fluence. But the decreasing trend of 2Pr is suppressed under high electric fields. Furthermore, the 2Pr degradation with cycling is abated by proton radiation. These results show that the HYO-based ferroelectric memory is highly resistive to proton radiation, which is potentially useful for space applications.