Improved photoluminescence of vertically aligned ZnO nanorods grown onBaSrTiO3 by pulsed laser deposition

Abstract

ZnO nanorods were grown on a variety of substrates such as Si,SiO2/Si and sapphire in a large-area pulsed laser deposition chamber designed for sensor device fabrication.Processing conditions were optimized to grow ZnO nanorods with or without seed layers. Au, Cr andBaSrTiO3 (BST) seed layers were investigated to compare their effects on the diameter andorientation of ZnO nanorods. ZnO nanorods were observed to align better when grown onsapphire, Cr or BST seed layers as compared to Au or Si layers. The highest qualitynanorods were those grown on BST seed layers, as shown by 4 K photoluminescencedonor-bound-exciton linewidths of only 0.5 meV.