Tunable photoluminescence properties of well-aligned ZnO nanorod array by oxygen plasma post-treatment

Well-aligned ZnO nanorod arrays were prepared on Si substrates modified with ZnO seeds using a low temperature hydrothermal method. In particular, photoluminescence (PL) properties of the ZnO nanorods can be easily tuned by varying the treatment duration of O2 plasma. Penetration depth of oxygen ions near the surface is suggested to influence the effect of O2 plasma on modification of PL properties for ZnO nanorods with different sizes. O2 plasma-tuned optical quality for ZnO nanorods has been attributed to the change of depletion region width.