Atmospheric pressure chemical vapor deposition growth window for undoped gallium antimonide

Metalorganic chemical vapor deposition (MOCVD) GaSb growth using trimethylg allium and trimethylantimony as a function of substrate temperature and V/I II ratio was examined. These parameters were found to have a significant ef fect on the growth rate and surface morphology of the GaSb films. A phase d iagram is used to interpret the effect of these growth parameters on the Ga Sb film growth. The region of single-phase growth was found to be narrow, f alling between 540 and 560 degrees C. The optimum growth conditions for the MOCVD growth of GaSb have been determined for a TMGa flow rate of 20 seem and a carrier gas flow of 8 1/min. The optimum substrate temperature and V/ III ratio were found to be 540 degrees C and 0.72, respectively. In these c onditions the lowest hole concentration of 5 x 10(16) cm(-3) and the highes t room temperature mobility of 500 cm(2) V-1 s(-1) were achieved, accompani ed by a steep, well-resolved band edge at 0.72 eV.