Metal-Organic Chemical Vapor Deposition of Aluminum from Trialkylamine Alanes

Abstract

ABSTRACTTrialkylamine alanes are attractive precursors for the metal-organic chemical vapor deposition (MOCVD) of aluminum thin films in microelectronics applications. The weak Al-N interaction and the absence of Al-C bonds (which decompose by highly activated processes) make these compounds excellent alternatives to the most widely studied Al CVD precursor, triisobutyl aluminum (TIBA). Solid trimethylamine alane (TMAA) and liquid triethylamine alane (TEAA) have vapor pressures at room temperature of 1 and 0.5 torr, respectively. In addition, these compounds are stable, non-pyrophoric, and are easily prepared. We report parallel studies of Al CVD in a low pressure, cold wall reactor and in an ultrahigh vacuum chamber to understand both the surface chemistry and the growth morphology. These studies, in turn, are compared with the decomposition chemistry and MOCVD characteristics of TIBA.