No abstract

ZnO:Al (ZAO) films were deposited on fused silica substrates heated to 350 °C by dc magnetron reactive sputtering from a Zn target mixed with 1.5 wt% Al. Films deposited on a substrate heated to a temperature between room temperature and 300 °C were (001)-oriented crystals, but those grown at 350 °C consisted of crystallites with (001) and (101) orientations. The dependence of electrical properties such as resistivity, carrier concentration, and Hall mobility on temperature was measured. The results indicate that the carrier concentration and Hall mobility increase with increasing temperature up to 250 °C, though the Al content remains unchanged in this temperature range. The probable mechanisms are discussed. The minimum resistivity of ZAO films is 4.23 × 10−4 Ω cm, with a carrier concentration of 9.21 × 1020 cm−3 and a Hall mobility of 16.0 cm2 v−1 s−1. The films show a visible transmittance of above 80%.

The reduction of FeO from iron-saturated FeO-CaO-SiO 2 -MgO-Al 2 O 3 -TiO 2 slags by graphite has been studied under static conditions between 1473 and 1623 K. The results show that the Fe/Ti mole ratio in the sample matrix decreases with increasing time and temperature. Most of the FeO was reduced within the first 10 min at 1573 K. The degree of reduction was found to increase rapidly with increasing temperature below 1573 K and was controlled not only by the effective diffusivity of CO and FeO concentration, but also the formation of iron-titanium oxide in the sample. At the same time and temperature, the degree of reduction of FeO in Ti-bearing slag was higher than that of Ti-free slag, because TiO 2 can decrease the liquidus temperature and prompt reduction of the slag.