Formation and evolution of Au-SiOx Heterostructures: From nanoflowers to nanosprouts

This work reports the formation of circular cavities and Au-SiOx nanoflowers after annealing thin Au film deposited on SiO2/Si substrates, transformation to nanosprouts with increasing time. Two reference experiments indicate that both H2 Si are indispensable for above structures. The can be attributed SiO2 layer decomposition product, volatile SiO, provides a source at early stage. A model is proposed SiO gas produced Si/SiO2 interface diffuse surface assisted by defects in before decomposed exposed. Then exposing those introduces another from active oxidation substrate, provoking change direction main source, which turn makes one nanoparticle nanoflower split two finally form nanosprout. about escape further details process, mechanism nanosprout sheds light feasible nanofabrication method design tunable size shape nanoparticles.