Surface rate-limiting steps and modelling of the nitrogen growth kinetics of GaAs1-xNx/GaAs

The growth features of the nitrogen incorporation into GaAs grown by metalorganic vapour phase epitaxy (MOVPE) are presented, with a comparison between experimental results and a kinetic model. The so-called ´distribution coefficient´ of nitrogen varies in the range 180-1000 depending essentially on growth temperature. Experimental results were analysed with a schematic process of surface reaction kinetics for controlling the mass transfer. Some kinetic rate constants are proposed. The modelling of N incorporation at 520-560°C allows an identification of species coming from the DMHy thermal decomposition. Surprisingly, this study shows that the rate of N incorporation weakly depends on the arsenic precursor at low growth temperatures.