Post-growth annealing treatments in the range 400-600 degrees C are performed on GaSb/GaAs Interfacial Misfit grown samples. Current density-voltage (J-V), Capacitance-voltage (C-V), capacitance-frequency (C-F) and Deep Level Transient Spectroscopy (DLTS) measurements are performed On as-grown and annealed samples. Our studies show that possible defect compensation is observed with the annealing treatments, resulting in a significant improvement in the performances of the devices. (C) 2015 Elsevier B.V. All rights reserved.