Temperature dependence of capacitance/current–voltage characteristics of highly (0001)-oriented YMnO3 thin films on Si

Abstract

Highly (0001)-oriented ${\mathrm{YMnO}}_{\mathrm{3}}$ thin films on Si(100) substrates were obtained by using a stable precursor solution and rapid thermal annealing at a low temperature of $\text{650\hspace{0.05em}°}\mathrm{C}$ in a chemical solution deposition process. Temperature-dependent capacitance–voltage $\mathrm{(C–V)}$ and current–voltage $\mathrm{(I–V)}$ characteristics were discussed in a metal-ferroelectric-semiconductor structure. At 300 K, the voltage-dependent increase of the memory window $\mathrm{(\Delta V)}$ in the $\mathrm{C–V}$ curve and the asymmetric $\mathrm{I–V}$ curve were attributed to the formation of positive interfacial charges by field- and thermal-excited electron transport. On the other hand, at 220 K, the voltage-independent $\mathrm{\Delta V}$ was attributed to ferroelectric polarization switching.