<i>In situ</i>growth of SnO₂nanorods by plasma treatment of SnO₂thin films

Abstract

SnO2 thin films were deposited by RF inductively coupled plasma enhanced chemical vapour deposition and then the as-deposited SnO2 thin films were immersed in the plasma for plasma post-treatment. Uniform SnO2 nanorods were grown in situ from the SnO2 thin films during plasma treatment and formed a hybrid structure of SnO2 nanorod thin films consisting of one-dimensional SnO2 nanorods embedded in the two-dimensional SnO2 thin film matrix. The growth of SnO2 nanorods follows a sputtering redeposition mechanism. Due to the intrinsically small grain size and high surface-to-volume ratios associated with the nanorods, the SnO2 nanorod thin films showed much higher sensitivity at lower operating temperatures together with faster response and shorter recovery time compared with the as-deposited SnO2 thin films.