Electrical Characterization and Materials Stability Analysis of ${rm La}_{2}{rm O}_{3}/{rm HfO}_{2}$ Composite Oxides on n-${rm In}_{0.53}{rm Ga}_{0.47}{rm As}$ MOS Capacitors With Different Annealing Temperatures

摘要

In this letter, a high-k composite oxide composed of ${rm La}_{2}{rm O}_{3}$ and ${rm HfO}_{2}$ is investigated for n-${rm In}_{0.53}{rm Ga}_{0.47}{rm As}$ metal–oxide–semiconductor (MOS) capacitor application. The composite oxide was formed by depositing five layers of ${rm La}_{2}{rm O}_{3}$ (0.8 nm)/${rm HfO}_{2}$ (0.8 nm) on InGaAs with post deposition annealing at 500$^{circ}{rm C}$. The MOS capacitors fabricated show good inversion behavior, high capacitance, low leakage current, with excellent interface trap density $(D_{{rm it}})$ of $7.0times 10^{11}~{rm cm}^{-2}{rm eV}^{-1}$, small hysteresis of 200 mV and low capacitance equivalent thickness of 2.2 nm at 1 kHz were also achieved.