Growth of aluminum oxide nanorods using sandwich structures composed of Al and SiO x layers

In this work, we report a simple method for growing aluminum oxide nanorods based on low‐temperature annealing of a sandwich structure composed of a thin Al film sandwiched between two silicon‐rich oxide (SiO x : 0 <  x  < 2) layers produced by plasma‐enhanced chemical vapor deposition. Aluminum oxide nanorods produced using a typical sandwich structure of SiO 1.4 (20 nm)/Al(2 nm)/SiO 1.4 (20 nm)/Si substrate exhibited the features of the mean diameter and length of the nanorods of about 0.3 and 1.7 μm, respectively. A possible growth mechanism is discussed on the basis of the vapor–solid process. The nanorod growth is proposed to be mediated by a vapor–solid mechanism in which the dominant vapor‐phase source of reactants is Al 2 O/AlO produced by a phase separation of SiO x .