1 / 11

Cu(I ) based delafossites as candidate materials for p -type transparent conducting oxides

This article discusses the potential of Cu(I)-based delafossites as candidate materials for p-type transparent conducting oxides. Considerations such as positive charge carriers, bandgap, and hole mobility are outlined. The structural characteristics of CuMO2 delafossites and the rational design of a p-type delafossite TCO are also explored. Examples of CuAlO2 as an optically transparent delafossite are provided, along with its semiconductive temperature dependence and doping effects. The article concludes by highlighting the leading status of Cu(I)-based delafossites for p-type TCO applications and acknowledging the tradeoff between transparency and conductivity in doped compounds.

yarbrough
Download Presentation

Cu(I ) based delafossites as candidate materials for p -type transparent conducting oxides

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cu(I) based delafossites as candidate materials for p-type transparent conducting oxides 05/28/10 Roy Rotstein

  2. ITO widely used in electronic devices

  3. Considerations for p-type TCO • Positive charges (holes) act as charge carriers • Bandgap must be greater than 3eV to avoid absorption in the visible spectrum • Localization of upper edge of valence band to oxides results in low hole mobility

  4. Structural characteristics of CuMO2delafossites M3+ Cu(I) oxygen Gabriel Delafosse Space Group: R3m

  5. Rational design of a p-type delafossite TCO • Covalent bonding behavior between cation and oxide helps reduce localization of 2p electrons from oxide • Cation must have a closed electronic shell • Avoid coloration from intra-atomic excitation • Energy level must be comparable to 2p electrons from oxides

  6. CuAlO2 optically transparent Estimated Eg = 3.5 eV Film thickness: 500nm Kawazoe, Hiroshi; et al. "P-type Electrical Conduction in Transparent Thin Films of CuAlO2." Nature 389 (1997): 939-42.

  7. CuAlO2 exhibits semiconductive temperature dependence Conductivity at room temperature: 0.095 S/cm Carrier density: 1.3 * 1017 cm-3 Hole mobility: 10.4 cm2-V1s-1 Seebeck coefficient: 183μVK-1

  8. Doping with divalent cations increases conductivity Film Thickness: 250nm Conductivity at room temperature: 200 S cm-1 Nagarajan, R., A. D. Draeseke, A. W. Sleight, and J. Tate. "P-type Conductivity in CuCr1-xMgxO2 Films and Powders." Journal of Applied Physics 89.12 (2001): 8022-025.

  9. Annealing at 900°C increases transparency but reduces conductivity Pre-annealing: 200 S cm-1 Post-annealing: 1 S cm-1

  10. Conclusions • Cu(I) based delafossites are the leading candidate materials for p-type TCO • Origin of p-type behavior unkown for undoped compounds • Tradeoff between transparency and conductivity in doped compounds

More Related