Absolute characterization of photoluminesence from pulsed‐laser deposited, sol‐gel, sputtered and evaporated ZnO thin films

ZnO thin films were fabricated using PLD, sputtering, e‐beam evaporation and sol‐gel techniques. The films were annealed in an oxygen environment to improve their crystallinity. Photoluminescence efficiency and angular emission patterns were characterized and are reported in absolute radiometric units. Conversion efficiencies in the range of 1 – 7 · 10^‐6 were found for the PLD films, 7 · 10^‐6 for a sputtered film, 7 – 40 · 10^‐6 for the e‐beam evaporated films, and 20 – 400 · 10^‐6 for the Sol‐Gel films. In most cases, the angular emission pattern of the photoluminescence was lambertian in nature. Non‐lambertian emission patterns were observed for some films with microstructure, achieved with PLD and e‐beam evaporation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)