Influence of the partial pressure of GaCl3 in the growth process of GaN by HVPE under nitrogen

This study presents the results of experiments performed in a conventional atmospheric horizontal HVPE reactor. The growth results are analysed with a model based on two desorption mechanisms of chlorine. The kinetic of the epitaxial film growth of GaN on sapphire by hydride vapour phase epitaxy is investigated under a variety of experimental conditions. The growth rate and the parasitical deposit on the quartz walls of the reactor upstream and above the substrate depend on the reactor geometry and on the composition of the vapour phase. The result of the experiment for a zero supersaturation over the substrate is discussed. Theoretical calculations compared with experimental results show the non-homogeneity of the gaseous species and the non-equilibrium of the GaCl3 in the vapour phase.