In-situ Measurement of the Decomposition of GaN OMVPE Precursors by Raman Spectroscopy

摘要

The homogeneous gas phase decomposition of TMGa and NH_3 in an inverted, vertical cold-wall reactor was studied in-situ by Raman spectroscopy. Pure rotational Raman scattering from the earrier gas (N2) was used to determine the temperature variations in the reactor, and the vibrational Raman spectra of the precursor molecules were used to measure species concentration profiles. It was found that the pyrolysis of TMGa and NH_3 in a N_2 environment is initiated above 623 K and 673 K, respectively, and the temperature ranges over which pyrolysis occurs were wider than previously reported using an isothermal flow tube apparatus.