Study of the influence of the complex carbon-hydrogen in GaAs films grown by MOCVD

The results of the characterization of GaAs epitaxial films are presented. Emphasis is made in the identification of the residual impurities and the possible existence of C-H complexes. For the growth of the GaAs epilayers trimethylgallium was used as gallium precursor and metallic arsenic was used as the arsenic source. According to the behavior of the carrier concentration and mobility as a function of growth conditions, the GaAs epilayers result with intermediate values of electrical compensation. As the GaAs epilayers were grown by MOCVD, the presence of C-H complexes in the films is expected and must be considered to explain electrical properties of the GaAs films. The electrical characterization was done by the van der Pauw method. FTIR spectroscopy was used to identify the carbon complex in the GaAs films.