The Chalcogenide-Fluorides MCuQF as P-Type Transparent Conductors
Abstract
(M_1-xM'_x)Cu(Q_1-yQ'_y)F (M, M' = Ba, Sr, Ca; Q, Q'= S, Se, Te) are materials with band gaps that allow transmission of much of the visible spectrum. They are p-type conductors, and the conductivity can approach 100 S/cm in BaCuSF and BaCuSeF powders doped with 5and films of BaCuSF exhibit strong red luminescence under ultra-violet excitation, and this luminescence is suppressed by K doping. These properties make them promising candidates for transparent electronic materials. BaCuSF is transparent in thin film form with a band gap of 3.1 eV. Other chalogenides substitute easily for S and solid solutions are readily achieved. The band gaps were obtained form wavelength-dependent diffuse reflectance measurements using an integrating sphere. The band gaps decrease linearly with decreasing cell volume according to Vegard's law. The band gap of BaCuSeF is 2.9 eV, and further reduction to 2.7 eV is observed in BaCuSe_0.5Te_0.5F. Additional weak tuning of band gap and electrical properties can be achieved by replacing Ba with Sr. This work is supported by the National Science Foundation.
- Publication:
-
APS Northwest Section Meeting Abstracts
- Pub Date:
- May 2003
- Bibcode:
- 2003APS..NWS.H3003P