HIGH-TEMPERATURE LIQUID-PHASE EPITAXY OF (100) ORIENTED GAINASSB NEAR THE MISCIBILITY GAP BOUNDARY

The Ga1-xInxAsySb1-y quaternary alloy has been grown by liquid phase epitaxy at high temperature (T = 600-615° C) on (100) oriented GaSb substrate. The highest indium concentration in the solid phase that could be achieved for perfect GaSb-lattice-matched layers was x = 0.23, which corresponds to a band-gap cut off wavelength λ = 2.39 μm at room temperature. Thermodynamical calculations show this composition (x = 0.23 y = 0.20) is situated at the boundary of the solid phase miscibility gap (binodal curve). Mismatched quaternary layers with more indium content (up to x = 0.52) could be grown outside the miscibility gap, but their morphology was bad. © 1990.