The growth and characterization of AlGaAs using dimethyl aluminum hydride

Abstract

The growth of AlGaAs by organometallic chemical vapor deposition has traditionally been done using trimethyl aluminum (TMA). The use of TMA, however, leads to a high level of carbon in the AlGaAs layers. In this study, we have investigated the use of dimethyl aluminum hydride (DMAH) as an alternative aluminum source. DMAH is a liquid at room temperature with a favorable vapor pressure of 2 Torr at 25°C. We report on the decomposition studies of DMAH and the growth and characterization of AlGaAs grown using the new compound. Preliminary low temperature PL spectra indicate that carbon acceptors are greatly reduced in layers grown under conditions similar to those used when growing with TMA. These results are supported by our finding the DMAH, when independently decomposed yields high purity aluminum metal, in contrast to TMA which yields aluminum carbides.