Comparative Study of High-k/GaSb Interfaces for Use in Antimonide Based MOSFETs.

Electrical interface quality of various high-k dielectrics on GaSb, including Al2O3, HfO2, LaAlO3, GdScO3, and HfO2/Ga2O3 bilayer has been studied and compared with reference low (AlGaSb) and high Dit (native oxide) interfaces using photoluminescence intensity measurements for the first time. Al2O3 and HfO2/Ga2O3 bilayer dielectrics are identified with the lowest interface recombination velocity (S=7\times 10^4~cm/s) and consequently Dit integrated across essentially the entire bandgap. However, S for even the best identified high-k dielectrics is elevated by 140\times over the low Dit AlGaSb reference indicating the need of further improvements for envisioned use in Sb based MOSFETs. [ABSTRACT FROM AUTHOR]