Coherently strained AlxGa1-xAsySb1-y epitaxial layers were grown over the range 0 < x < 0.2 and y similar to 0.5 on TnP substrates by organometallic vapor phase epitaxy (OMVPE). The Al distribution coefficient was found to be much less than unity and this was attributed to reactions between trimethylaluminum and trimethylantimony at the growth temperature of 550 degrees C. Low-temperature photoluminescence (PL) spectra for AlxGa1-xAsySb1-y, showed single PL peaks for which the energy increased with increasing Al content in the layers in approximate agreement with theoretical predictions for the band gap of AlGaAsSb. P-type doping of AlGaAsSb up to 1.2 x 10(20)cm(-3) was achieved using CBr4. The growth rate of AlGaAsSb epilayers decreased with increasing CBr4 dopant flow rates. (c) 2005 Elsevier B.V. All rights reserved.