| Title |
Effect of Substrate Bias Voltage on the Electrical Properties of ZnO:Al Transparent Conducting Film Deposited on Organic Substrate |
| Keywords |
ZnO:Al Transparent Conducting Rim ; Electrical Resistivity ; Optical Transmittance ; Bias Voltage |
| Abstract |
In this paper, ZnOAl thin film was deposited on polyethylene terephthalate(PET) substrate by capacitively coupled r. f. magnetron sputtering method from a ZnO target mixed with 2 wt[%] Al2O3 to investigate the possible application of ZnOAl film as a transparent conducting electrode for film typed DSCs. The effect of substrate bias on the electrical properties and film structure were studied. The results showed that a positive bias applied to the substrate during sputtering contributed to an improvement of electrical properties of the film by attracting electrons in the plasma to bombard the growing films. These bombardments provided additional energy to the growing ZnO:Al film on the substrate, resulting in significant variations in film structure and electrical properties. Electrical resistivity of the film decreases significantly as the positive bias increases up to ＋30[V]. However, as the positive bias increases over ＋30[V], the resistivity decreases. The transmittance varies little as the substrate bias is increased from 0 to ＋ 60[V], and as r. f. powers increases from 160[W] to 240[W]. The film with electrical resistivity as low as 1.8×10-3[Ω-㎝] and optical transmittance of about 87.8[%] were obtained for 1,012[㎚] thick film deposited with a substrate bias of ＋30[V]. |