Ga doped ZnO (GZO) thin films were prepared by rf-magnetron sputtering on glass substrate for window heater applications. Electrical and optical properties of these films were analyzed in order to investigate on substrate temperature and rf power dependencies. High quality GZO films with a resistivity of 1.30 x 10(-4) Omega cm and a transparency above 90% in the visible range were able to be formed. GZO films have been patterned on glass substrate as a line heater. This GZO line heater showed the rapid heat radiation property from room temperature to 90 degrees C for 22 s at the applied voltage of 42 V. These results could provide a possibility to use GZO as effective transparent heaters. (c) 2007 Elsevier B.V. All rights reserved.