Coherent Anti-Stokes Raman Scattering Measurements of Group V Hydride and Trimethylgallium Decomposition in Organometallic Vapor Phase Epitaxy

ABSTRACTThe thermal decomposition of AsH3 and TMG is measured insitu under different experimental conditions. Simultaneously the production of H2, CH4 and C2H6 is observed. The data indicate a situation where AsH3 is only partially decomposed at the GaAs surface. The hydrogen released removes additional CH3 groups from the trimethyl-gallium (TMG) molecule, enhances the decomposition of TMG, and thereby forms methane.