Tertiarybutylhydrazine: a new precursor for the MOVPE of group III-nitrides

摘要

Tertiarybutylhydrazine (tBuHy), generated from tBuHy hydrocloride, was found to have a convenient vapor pressure (6.7 mbar at 20 deg C) for MOVPE applications. Thermolysis of tBuHy, studied by quadrupole mass spectroscopy (QMS), starts at about 220 deg C by homolytic cleavage into reactive tBuNH and NH_2 radicals. Almost complete decomposition under QMS conditions is observed above 350 deg C. Mirror-like GaN epilayers with mixed cubic hexagonal and hexagonal structure were grown on GaAs and Al_2O_3 substrates, respectively, at 670 deg C using tBuHy and Me_3Ga or Et_3Ga with a V/III ratio of 70. Low carbon incorporation was found in tBuHy-grown layers with respect to layers grown with Me_2Hy under the same conditions.