AVS 51st International Symposium
    Thin Films Thursday Sessions
       Session TF-ThA

Paper TF-ThA6
Transparent and Semi-Transparent Conducting Film Deposition by Reactive-Environment, Hollow Cathode Sputtering

Thursday, November 18, 2004, 3:40 pm, Room 303C

Session: Photovoltaic Thin Films
Presenter: S.Y. Guo, Energy Photovoltaics, Inc.
Authors: A.E. Delahoy, Energy Photovoltaics, Inc.
S.Y. Guo, Energy Photovoltaics, Inc.
Correspondent: Click to Email
Highly transparent and conductive In@sub 2@O@sub 3@ and ZnO films containing different doping elements such as Mo, Zr, Nb, Ta, W (for In@sub 2@O@sub 3@) and Al, B (for ZnO) have been prepared by the reactive-environment, hollow cathode sputtering method.@footnote 1@ The use of Nb and W as effective dopants is reported for the first time. Metallic targets were used exclusively, and the dopant concentration was easily controlled using a second sputtering power supply. As a result of the cathode and gas flow geometry, the sputtering is conducted in metal mode, and the target and doping materials are free from oxidation during the deposition process. Film resistivities achieved with the various dopants will be reported. For In@sub 2@O@sub 3@:Mo, a resistivity of 1.6x 10@super -4@ @ohm@-cm and a mobility of 80 cm@super 2@/Vs were achieved for Mo concentrations in the range 0.5-5.0% as measured by ICP. XPS analysis indicates Mo with a +6 valence state. The dependences of film resistivity on substrate temperature during preparation and film temperature during measurement will be presented and discussed. Different dominant scattering mechanisms can be seen in different films. Reasonably transparent films of CuAlO@sub 2@ will be reported. And remarkably, semi-transparent films of InN having sheet resistances of 12 @ohm@/square have also been prepared. A scaled-up linear cathode 50 cm in length is under construction, and we expect to report results for ZnO:B deposited using this source. @FootnoteText@ @footnote 1@A. E. Delahoy, S. Y. Guo, C. Paduraru, and A. Belkind, J. Vac. Sci. Technol. A 22 Jul/Aug 2004.