Molecular Beam Epitaxial Regrowth of Antimonide-Based Semiconductors

We have investigated regrowth of p + InGaSb on AlGaSb and on thin InAs etch-stop layers after atomic hydrogen cleaning (AHC) surface treatments. Following certain cleaning conditions, the surface morphologies for In 0.27 Ga 0.73 Sb regrown on InAs exhibit smooth surfaces with similar root-mean-square (rms) roughness to the as-grown InAs, which in turn is similar to the roughness of the AlGaSb buffer layer below it. In addition, hole mobilities for InGaSb regrown on AHC InAs approach the highest mobilities reported to date for any p + III–V semiconductors. A wide range of AHC conditions including substrate temperatures from 280°C to 370°C and exposure durations between 5 min and 30 min result in smooth InGaSb films with low resistivity.