We report the growth process of silica nanowires (NWs) grown by using a thick Au film as a catalyst,and
suggest an alternative vapor–liquid–solid mechanism for NW growth.The silica NWs were grown by
high-temperature annealing of silicon substrates coated with an Au film measuring either 20 nm or
60 nm thick in a N2 atmosphere. A number of Au particles were observed inside the NWs,unlike NWs
grown a single Au particle at their top.The results are attributed to the push-up growth of NWs by the
continuous formation of siliconoxide on the top and/or side surfaces rather than underneath of the
eutectic liquid Au–Si alloy suggested in the conventional vapor–liquid–solid process.