Annealing of gold nanoparticles on GaP(111)B: initial stage of GaP nanowire growth

GaP(111)B substrate was strewn with 30 nm colloidal Au nanoparticles. Organic residues were removed by: A) boiling in acetone and isopropylalcohol followed by a DI water rinse, B) treatment A + HF:H 2 O, C) treatment A + O 2 plasma for 10 min, 20 min, and 40 min, and D) treatment A combined with O 2 plasma (10 min) and HF:H 2 O. The substrate thus had original ‘epi‐ready' oxides (A), or fresh native oxides (B and D), or new added oxides (C). The samples were annealed at T a = 650 °C for 10 min under PH 3 and H 2 in an MOVPE chamber. This resulted in the growth of GaP stumps along [111]B on each sample. Their length was <3 nm (B and D), ∼20 nm (A), and ∼220 nm (C 40 min). Elemental Ga is left as P 2 O 5 /Ga 2 O 3 oxides form on etched GaP(111)B at room temperature. We believe that as the oxides disintegrated during annealing, they released the elemental Ga that combined with phosphorus from PH 3 , and this led to the growth of the GaP stumps. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)