@article{3719ccd82d9a4a19905ad0e961e62184,
title = "Carrier concentration tuning of bandgap-reduced p -type ZnO films by codoping of Cu and Ga for improving photoelectrochemical response",
abstract = "In this study, the synthesis of p -type ZnO films with similar bandgaps but varying carrier concentrations through codoping of Cu and Ga is reported. The ZnO:(Cu,Ga) films are synthesized by rf magnetron sputtering in O2 gas ambient at room temperature, followed by postdeposition annealing at 500 °C in air for 2 h. The bandgap reduction and p -type conductivity are caused by the incorporation of Cu. The tuning of carrier concentration is realized by varying the Ga concentration. The carrier concentration tuning does not significantly change the bandgap and crystallinity. However, it can optimize the carrier concentration to significantly enhance the photoelectrochemical response for bandgap-reduced p -type ZnO thin films.",
author = "Sudhakar Shet and Ahn, {Kwang Soon} and Yanfa Yan and Todd Deutsch and Chrustowski, {Kevin M.} and John Turner and Mowafak Al-Jassim and Nuggehalli Ravindra",
note = "Funding Information: This work was supported by the U.S. Department of Energy through the UNLV Research Foundation under Contract No. DE-AC36-99-GO10337. FIG. 1. XRD curves of ZnO:(Cu,Ga)0.001, ZnO:(Cu,Ga)0.002, ZnO:Cu, and ZnO samples with similar thickness of about 0.5 μ m . The dotted lines indicate the peaks from FTO substrate. FIG. 2. AFM images taken from (a) ZnO:Cu, (b) ZnO:(Cu,Ga)0.001, and (c) ZnO:(Cu,Ga)0.002 samples. FIG. 3. (a) Optical absorption curves and (b) absorption coefficients of ZnO, ZnO:Cu, ZnO:(Cu,Ga)0.001, and ZnO:(Cu,Ga)0.002 samples. FIG. 4. Photocurrent-voltage curves under (red curve) continuous illumination, (black curve) dark condition, with an UV/IR filter measured from (a) ZnO and (b) ZnO:Cu films. FIG. 5. Photocurrent-voltage curves under (arrowed) continuous illumination, (black curve) dark condition, with an UV/IR filter measured from ZnO:Cu, ZnO:(Cu,Ga)0.001, and ZnO:(Cu,Ga)0.002 films. FIG. 6. XRD curves of ZnO:(Cu,Ga)0.01, ZnO:(Cu,Ga)0.03, ZnO:Cu, and ZnO samples with similar thickness of about 1 μ m . The dotted lines indicate the peaks from FTO substrate. FIG. 7. (a) Optical absorption curves and (b) absorption coefficients of ZnO:Cu, ZnO:(Cu,Ga)0.01, and ZnO:(Cu,Ga)0.03 samples. FIG. 8. Photocurrent-voltage curves under (red curve) continuous illumination, (black curve) dark condition, with an UV/IR filter measured from (a) ZnO:(Cu,Ga)0.01 and (b) ZnO:(Cu,Ga)0.03 films. ",
year = "2008",
doi = "10.1063/1.2888578",
language = "English (US)",
volume = "103",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics",
number = "7",
}