Analysis of trap state densities at HfO2 / In0.53Ga0.47As interfaces

摘要

HfO2 was deposited on n- and p-type In0.53Ga0.47As by chemical beam deposition. Interface trapndensities u0001Ditu0002 and their energy level distribution were quantified using the conductance method inna wide temperature range u000177 to 300 Ku0002. A trap level close to the intrinsic energy level caused thenDit to rise above 1013 cm−2 eV−1. The trap level at midgap gives rise to false inversion behavior innthe capacitance-voltage curves for n-type channels at room temperature. The apparent decrease ofnthe Dit close to the band edges is discussed.