Investigation on high carrier mobility in chromium incorporated CdO thin films on glass

Several sets of CdO thin films doped with different amount of chromium have been grown on glass substrates by a vacuum evaporation technique. The effects of Cr doping on the structural, electrical, and optical properties of the host CdO films were systematically studied. The X-ray diffraction study shows that some of Cr ions occupied locations in interstitial positions and/or Cd-ion vacancies in CdO lattice. The bandgap of Cr-doped CdO suffer variations that were studied in the framework of the available models based on simultaneous effects of bandgap widening and bandgap narrowing. The electrical behaviours show that all the prepared Cr-doped CdO films are degenerate semiconductors. However, the Cr doping influences all the optoelectrical properties of CdO. Their dc-conductivity carrier concentration and mobility increase with small 1-1.8% Cr-incorporation level compare to undoped CdO film. The largest mobility (85.2 cm2/V.s) and conductivity (2150 S/cm) were measured with 1.3%Cr. From near infrared-transparent-conducting-oxide (NIR-TCO) point of view, Cr is effective for CdO slight dopin