Growth of GaS on GaAs(100)-(4 x 2) with the single-source precursor [(Bu-t)GaS](4)

The growth of a GaS film on the GaAs(100)-(4 x 2) surface, using [(Bu-t)GaS ](4), has been studied in ultra-high vacuum using high-resolution electron energy loss spectroscopy (HREELS), Auger electron spectroscopy (AES), low-e nergy electron diffraction (LEED), and temperature-programmed desorption (T PD). Upon the adsorption of a monolayer of GaS, we observed the formation o f a (2 x 1) superstructure, as evidenced by LEED. For multilayer growth at 650 K, a (1 x 1) LEED pattern was observed. For submonolayer coverages of t he precursor adsorbed at 100 K, thermally induced beta-hydrogen elimination of the tert-butyl ligands was observed at 650 K, as evidenced by concurren t desorption of isobutene and molecular hydrogen. An amorphous GaS film is formed after multilayer adsorption of [(Bu-t)GaS](4) at 100 K, followed by annealing to 650 K. However, isobutane, isobutene; and molecular hydrogen d esorption is seen from such a surface: suggesting an additional tert-butyl ligand removal pathway. Finally, layer-by-layer growth of a GaS film was ac hieved by a cyclic process of monolayer adsorption of [(Bu-t)GaS](4) at 200 K, followed by annealing to 700 K. (C) 2000 Elsevier Science B.V. All righ ts reserved.