Sputtering-assisted metal-organic chemical vapor deposition of Yb-doped ZnO for photonic conversion in Si solar cells

We have grown Yb‐doped ZnO (ZnO:Yb) on c‐plane sapphire substrates by sputtering‐assisted metal‐organic chemical vapor deposition (SA‐MOCVD). X‐ray diffraction (XRD) revealed that these ZnO:Yb films exhibit a c‐axis orientation and that the lattice constant increases with Yb concentration. After annealing the samples at 600 °C for 0.5 h in O2, they showed a clear 980 nm emission due to the intra‐4f shell transitions of 2F5/2–2F7/2in Yb3+ ions. It turns out that Yb lu‐minescent centers with different local structures coexist, which exhibit different energy transfer processes from the ZnO host. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)