화학공학소재연구정보센터
Thin Solid Films, Vol.357, No.2, 151-158, 1999
A novel approach to prepare zinc oxide films: excimer laser irradiation of sol-gel derived precursor films
Crystalline zinc oxide films with a c-axis orientation were prepared by a new approach using KrF excimer laser irradiation of sol-gel derived precursor films on glass substrates. The structural characteristics, optical and electrical properties of the laser-irradiated films were investigated and compared with those of heat-treated films. Laser irradiation gives two kinds of crystalline zinc oxide films; irradiation at low energy fluence produces low crystallinity with weak orientation, while irradiation at high energy fluence produces high crystallinity with strong orientation. The differences in crystallinity and orientation are explained in terms of the thermal effect caused by laser irradiation. Laser processing characteristically created oxygen vacancy in contrast to conventional heat-treatment, resulting in a decrease in electrical resistivity of the films. In addition, film irradiated at high energy fluence shows a band structure with indirect band gap, although the other prepared films and a typical ZnO crystal show a band structure with direct band gap.