| 초록 |
ZnO is a potential material for oxide semiconductor applications. Undoped ZnO and Al-doped ZnO films were deposited using a spray pyrolysis technique and the films were treated with capacitively coupled O2 and Ar plasma at different Flow ratio, RF power and plasma process time. The ZnO and AZO sol concentration was 0.75 M. The samples were exposed to capacitively coupled O2 and Ar plasma at 70~90 mTorr. The RF power and exposed time were varied in the range of 0~150 W and 0~150 seconds, and O2:Ar flow ratio is also (20:0, 15:5, 10:10, 5:15, 0:20) respectively. The ZnO films were investigated using contact angle measurement, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, surface profilometry and atomic force microscope. The film thicknesses were measured about 1.4 µm at ZnO and AZO, respectively. The roughnesses of the film surfaces were 0.5~7.0 nm. The films deposited at 500 ºC because this temperature provide smoother surface than those at Transmittances of the films were about 80~90 % and optical energy bandgap were 3.29~3.4 eV, where the films processed at 90s( plasma process time), 10:10 (flow rate (O2:Ar) ) and over 50W (RF power) brought higher optical bandgap energies than the other conditions. I-V and UV response of the films also studied. The results will also be discussed during the talk. |
