Comparative Study of High- $k/{\rm GaSb}$ Interfaces for Use in Antimonide Based MOSFETs

Electrical interface quality of various high- k dielectrics on GaSb, including Al 2 O 3 , HfO 2 , LaAlO 3 , GdScO 3 , and HfO 2 /Ga 2 O 3 bilayer has been studied and compared with reference low (AlGaSb) and high D it (native oxide) interfaces using photoluminescence intensity measurements for the first time. Al 2 O 3 and HfO 2 /Ga 2 O 3 bilayer dielectrics are identified with the lowest interface recombination velocity (S=7×10 4 cm/s) and consequently D it integrated across essentially the entire bandgap. However, S for even the best identified high- k dielectrics is elevated by 140× over the low D it AlGaSb reference indicating the need of further improvements for envisioned use in Sb based MOSFETs.