Published online by Cambridge University Press: 21 February 2011
Alternative precursors to group-in nitrides have been studied based on two schemes: 1) The reaction Me3M (M=Al,Ga) with t-BuNH2 and 2) the decomposition of NH3 based adducts. Polycrystalline growth of AIN has been demonstrated by both routes. Decomposition of the adduct Me3Al:NH3 has been used to prepare epitaxial AIN on (0001) sapphire with an X-ray FWHM (full width at half maximum) of 16 arcrnin at a growth temperature of 1050C. Similar growth using analogous gallium precursors always resulted in gallium droplets. We have attributed this difference in chemical reactivities to the lower electronegativity of gallium compounds, thus leading to dissociation rather than sequential methane loss to form the nitride.