We show that surface reconstructions may play an essential role in determining the equilibrium solubilities of N, P, As, and Sb in various III-V compounds. In particular, anion–anion dimerization of the(001)-&bgr;2(2×4)surface can enhance the solubility of N near the surface in GaAs, GaP, and InP by five, three, and two orders of magnitudes, respectively, at 1000 K. With certain assumptions on the growth kinetics, this high concentration of N may be frozen in as the crystal grows. ©1997 American Institute of Physics.