The effect of deposition temperature on the properties of Al-doped zinc oxide thin films

Transparent and conductive aluminum-doped zinc oxide films have been prepar ed by RF reactive magnetron sputtering with different substrate temperature s. The structural characteristics of the films were investigated by the X-r ay diffractometry, scanning electron microscopy, atomic force microscopy an d transmission electron microscopy, while the electric and optical properti es of the films were studied by the Hall measurement and optical spectrosco py, respectively. It has been found that all of the films deposited were fl at and smooth with a c-axis preferred orientation perpendicular to the subs trate. The lowest resistivity obtained in this study was 4.16 x 10(-4) Omeg a cm for the films deposited at the substrate temperature of 250 degreesC. By calculating the mean free path of electrons, ion impurity scattering is considered to be the dominant factor for the decrease of conductivity. Opti cal transmittance measurement results show a good transparency within the v isible wavelength range for the films deposited at substrate temperatures a bove 200 degreesC. (C) 2001 Elsevier Science B.V. All rights reserved.