Two-dimensional numerical simulation on growth Fate non-Uniformity of selective area growth (SAG) in metal-organic vapor phase epitaxy (MOVPE) is an effective method to examine the surface reaction kinetics, which is difficult to be investigated in mass-transport limited growth regime. Non-linear kinetic analysis based on the Langmuir-Hinshelwood mechanism is revealing the intrinsic process in MOVPE. Two important kinetic parameters, Surface reaction rate constant (k(s)(n)) and adsorption equilibrium coefficient (K), were successfully extracted from GaAs SAG-MOVPE on (100) exact and 2 degrees off misoriented substrates in the temperature range of 520-600 degrees C. The activation energy is 126-127 kJ/mol for k(s)(n), and -53 to -59 kJ/mol for K. The surface coverage of Ga-species during the GaAs growth can be estimated from these kinetic parameters as 0.05-0.60. There is a critical temperature (T-c) for the conversion of GaAs surface reaction mode, When growth temperature is higher than T-c, non-linear kinetic can be simplified as linear kinetic mode which is easier in calculation. T-c was found to be 600 degrees C for (100) exact GaAs Substrate and 650 degrees C for 2 degrees off substrate. (C) 2008 Elsevier B.V. All rights reserved.