Nitrogen-passivated dielectric/InGaAs interfaces with sub-nm equivalent oxide thickness and low interface trap densities

Abstract

We report on the electrical characteristics of HfO2 and HfO2/Al2O3 gate dielectrics deposited on n-In0.53Ga0.47As by atomic layer deposition, after in-situ hydrogen or nitrogen plasma surface cleaning procedures, respectively. It is shown that alternating cycles of nitrogen plasma and trimethylaluminum prior to growth allow for highly scaled dielectrics with equivalent oxide thicknesses down to 0.6 nm and interface trap densities that are below 2.5 x 10(12) cm(-2) eV(-1) near midgap. It is shown that the benefits of the nitrogen plasma surface cleaning procedure are independent of the specific dielectric. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4776656]