Electrical and optical properties of sputter deposited tin doped indium oxide thin films with silver additive

Tin doped indium oxide (ITO) films with a few mol% of silver were prepared by reactive DC magnetron sputtering. The purpose of adding silver is to boo st conductivity. The real part of the refractive index of ITO was determine d from ellipsometry data, applying a model combining a Drude and a Lorentz term. The imaginary part was calculated from the absorptance, which was der ived from transmittance and reflectance data. We found that up to 6 mol% of silver additive enhanced the conductivity by as much as a factor of two fo r layers post-treated at 200 and 300 degreesC in reducing gas consisting of 93% N-2 and 7% H-2. For samples with 1 mol% silver, which was post-treated at 100 and 200 degreesC, we observed an increase in the luminous transmitt ance. The transmittance decreased with increased silver content. (C) 2001 E lsevier Science B.V. All rights reserved.