Influences of lattice polarity of GaAs substrate on the growth of InN layers were investigated by metalorganic vapor-phase epitaxy (MOVPE). It was found that the polarity of InN was strongly affected and inherited by the polarity of GaAs substrate used (i.e., (111)A and (111)B). At low temperature, superior growth of InN occurred on the GaAs (111)B surface, which indicated the InN (0001) (N-polarity) should be grown dominantly. It was also found that the surface atom arrangement of GaAs surface influenced the crystalline quality of InN grown layer. It is important for obtaining a uniform and a high crystalline quality InN to eliminate the arsenic (As) species on the GaAs surface prior to the epitaxial growth. (c) 2006 Elsevier B.V. All rights reserved.