Composition control in the growth of AlAs1-xSbx alloys

The deposition of AlAs_1-xSb_x films is studied systematically using a metalorganic vapor-phase epitaxy technique. The composition of the alloys was found to be dependent strongly on the growth temperature. A high concentration of solid Sb can be achieved at an elevated temperature. It is interesting to note that for films grown at 600°C the AlAs content in AlAsSb is determined simply by the input gas ratio of [TBAs]/[TMAl] as the Sb reactant is supplied sufficiently. Owing to the insensitivity of Sb mole flow rate to solid composition at this particular growth environment, this result could be accounted for by thermodynamic arguments. Following this picture, an improved film controllability can be achieved for the growth of AlAs_1-xSb_x compounds