GaInNAs(Sb) quantum wells were grown by plasma-assisted molecular beam epitaxy on GaAs substrates. The effects of both growth temperature and the addition of Sb flux on the material quality were investigated with photoluminescence and x-ray diffraction. The photoluminescence intensity and structural quality of GaInNAs quantum wells drops rapidly as the growth temperature is increased above 480 degrees C. However, at a growth temperature of 500 degrees C, adding a relatively small amount of Sb dramatically recovers the photoluminescence intensity of the quantum well. Furthermore, the addition of Sb suppresses N surface diffusion, enabling the growth of high quality GaInNAsSb at temperatures as high as 530 degrees C. (c) 2005 American Vacuum Society.