Opto-electronic properties of chromium doped indium–tin-oxide films deposited at room temperature

Indium–tin-oxide (ITO) doped chromium films were deposited on Corning 7059 glass prepared by radio frequency (RF) magnetron sputtering under various levels of sputtering power for the chromium target. Experimental results show that the surface roughness slightly decreases by co-sputtering Cr. The pure ITO films deposited at room temperature were amorphous-like. At 15 W of chromium target power, the structure of ITO: Cr film mainly consists of (2 2 2) crystallization plane, with minority of (2 1 1), (4 4 0), (6 6 2) crystallization planes. The carrier concentration of the ITO films increases with increasing the doping of chromium, however the mobility of the carrier decreases. When the sputtering power of the chromium target is at 7.5 W, there has a maximum carrier mobility of 27.3 cm2 V −1 s −1, minimum carrier concentration of 2.47 × 1020 cm−3, and lowest resistivity of 7.32 × 10−4 Ω cm. The transmittance of all the chromium doped ITO films at the 300–800 nm wavelength region in this experiment can reach up to 70–85%. In addition, the blue shift of UV–Vis spectrum is not observed with the increase of carrier concentration.