Abstract
The photolysis of dimerized trimethylaluminum, Al2 (CH3) 6, (TMA) by excimer laser irradiation was investigated. The valence electronic structure of TMA was determined by photoelectron spectroscopy and molecular orbital (MO) calculations. On the basis of time-resolved optical emission spectroscopy combined with MO calculations, a model for the UV photolysis of Al2 (CH3) 6 was developed, in which Al and CH were produced in the gas phase through cascade one-photon absorption processes in Al2 (CH3) 6 and Al (CH3) n (n = 1, 2, 3). High-resolution electron-energy-loss spectroscopy (HREELS) was also used to study the adsorption and UV-laser-induced dissociation of TMA on the Si (100) 2 × 1 and Si (111) 7 × 7 surfaces. HREELS spectra from TMA single adlayers were consistent with those expected for nondissociatively adsorbed TMA dimers. No changes in the adlayer spectra were observed under KrF laser irradiation, while ArF laser irradiation caused the dissociation of adsorbed TMA and the desorption of some methyl ligands.
