Effects of Cr doping on physical properties of amorphous In-Ga-Zn-O films

Amorphous thin films of InGaZnO4 (a-IGZO) doped with Cr have been fabricated by using pulsed-laser deposition (PLD). The electrical, optical and magnetic properties of Cr-doped a-IGZO films grown at 25 °C and 150 °C were investigated. The conductivity, optical transmission and band gap of films are remarkably enhanced by increasing the growth temperature. Conductivity, carrier concentration and mobility decrease with increasing the Cr content. However, the optical transmission and band gap are not significantly affected by Cr doping. Moreover, all Cr-doped films exhibit room-temperature ferromagnetism.

▶ Cr-doped In-Ga-Zn-O films were fabricated on sapphire substrates by using pulsed laser deposition technique. ▶ The valence of Cr doped in In-Ga-Zn-O films is determined to be 3+ by XPS measurements. ▶ The electrical and magnetic properties of the films are found to be strongly affected by Cr doping. ▶ The optical properties are almost not affected by Cr doping. ▶ The Cr-doped In-Ga-Zn-O films exhibit room-temperature ferromagnetic characteristics.