We investigated the optical and transport properties of charge carriers in doped amorphous Tris (8-hydroxyquinolinato) aluminum (Alq(3)) films from room temperature to 130 degrees C. The doping concentration of dopant DCM was up to 24 wt% in Alq(3) films. The current-voltage, electroluminescence (Et) and light-current characteristics were measured. The current density was sharply increased up to a DCM concentration of 1.5 wt% in Alq(3) films for the same bias voltage. The EL peak position shifted from green to red color with DCM doping concentration in Alq(3). The highest EL efficiency was found for a DCM doping concentration of 0.5 wt%. The EL intensity was increased by about 2.5 times than that of the pure Alq(3). The EL intensity was reduced with temperature. (c) 2005 Published by Elsevier B.V.