Search

In this study, AZO thin films were deposited on glass by using a 98 mol% ZnO + 1 mol% Al2O3 (AZO, Zn : Al = 98 : 2) ceramic target and a r.f. magnetron sputtering system. At first, the effects of different H2 flow rates (H2/(H2 +Ar) = 0%~9.09%, abbreviated as H2-deposited AZO thin films, deposition temperature was 200°C) added during the deposition process on the physical and electrical properties of AZO thin films were investigated. The optical transmittance at 400 nm~700 nm is more than 80% for all AZO thin films regardless of H2 flow rate and the transparency ratio decreased as the H2 flow rate increased. The Burstein-Moss shift effect was used to prove that the defects of AZO thin films decreased with increasing H2 flow rate. Also, the 2% H2-deposited AZO thin films were also treated by the H2 plasma at room temperature for 60 min (plasma-treated AZO thin films). The value variations in the optical band gap (Eg) values of the H2-deposited and plasma-treated AZO thin films were evaluated from the plots of (αhv)² = c(hv - Eg), and the Eg values increased with increasing H2 flow rate. The Eg values also increased as the H2-plasma process was used to treat on the H2-deposited Al2O3-doped ZnO (AZO) thin films. [ABSTRACT FROM AUTHOR]

We investigated a two-stepmethod to deposit the ZnO-based nanostructure films, including nanorods and nanoflowers. In the first step, sputtering method was used to deposit the ZnO films on SiO2/Si substrates as the seed layer. In the second step, Zn(NO3)2- 6H2O and C6H12N4 were used as precursors and hydrothermal process was used as the method to synthesize the ZnO films. After that, the ZnO films were measured by an X-ray diffraction pattern and a FESEM to analyze their crystallization and morphology. We had found that the ZnO films had three different morphologies synthesized on ZnO/SiO2/Si substrates, including irregularplate structure films, nanorod films, and beautiful chrysanthemum-like clusters (nanoflower films). We would prove that the face direction of ZnO/SiO2/Si substrates in the hydrothermal bottle and deposition time were two important factors to influence the synthesized results of the ZnO films. [ABSTRACT FROM AUTHOR]

The (In, Ga, Zn)Ox (IGZO) thin films were deposited on glass substrates using cosputtering method in radio frequency magnetron sputtering system. Zn2Ga2O5 (Ga2O3-2 ZnO, GZO) and In2O3 ceramics were used as targets and dual guns were used to deposit the IGZO thin films. Deposition power of GZO target was 80 W and deposition power of pure In2 O3 target was changed from 70 W to 100 W, and the deposition time was 30 min. The effect of deposition power of In2O3 target on the crystalline, surface, electrical, and optical properties of the IGZO thin films was investigated at room temperature in a pure Ar atmosphere. The cosputtered IGZO thin films showed a very smooth and featureless surface and an amorphous structure regardless of the deposition power of In2O3 target due to the room temperature sputtering process. However, the cosputtered IGZO thin films exhibited transparent electrode properties because they had high transmittance ratio and low resistivity. The value variations in the optical band gap (Eg) values of the IGZO thin film were evaluated from the plots of (αhv)² = c(hv - Eg). We would also show that the deposition power of In2O3 target would have a large effect on mobility and Eg value of the IGZO thin films. [ABSTRACT FROM AUTHOR]

A compound of ZnO with 3wt% Ga2O3 (ZnO :Ga2O3 =97 : 3 in wt%, GZO) was sintered at 1400°C as a target. The GZO thin films were deposited on glass using a radio frequency magnetron sputtering system at 300°C by changing the deposition power from 50Wto 150W. The effects of deposition power on the crystallization size, lattice constant (c), resistivity, carrier concentration, carrier mobility, and optical transmission rate of theGZO thin films were studied. The blue shift in the transmission spectrumof the GZO thin films was found to change with the variations of the carrier concentration because of the Burstein-Moss shifting effect. The variations in the optical band gap (Eg) value of the GZO thin films were evaluated from the plots of (αhν])² = c(hν - Eg )1/2, revealing that the measured Eg value decreased with increasing deposition power. As compared with the results deposited at room temperature by Gong et al., (2010) the 300°C deposited GZO thin films had apparent blue shift in the transmission spectrum and larger Eg value. For the deposited GZO thin films, both the carrier concentration and mobility linearly decreased and the resistivity linearly increased with increasing deposition power. The prepared GZO thin films were also used as transparent electrodes to fabricate the amorphous silicon thin-film solar cells, and their properties were also measured. [ABSTRACT FROM AUTHOR]