分别采用反应磁控溅射和金属锌膜空气中热氧化两种方法,制备了两种氧化锌薄膜。X射线衍射实验发现,反应磁控溅射法制备的氧化锌薄膜结晶性能好,具有很高的c轴取向性,而金属锌膜热氧化法制备的氧化锌薄膜结晶性能相对较差,晶粒取向呈随机分布。对上述两种氧化锌薄膜进行了光电导测试,结果表明,反应磁控溅射制备的氧化锌薄膜的电阻率很高,没有明显的光电导,而金属锌膜氧化法制得的氧化锌薄膜电阻率较小,光电导现象非常明显。进一步分析结果表明,金属锌膜热氧化制备的氧化锌薄膜的光电导主要来自于表面吸附气体的吸附与解吸。
Two sets of ZnO thin films were prepared on quartz substrate. One set of them was deposited directly by reactive magnetron sputtering,the other set was prepared by a two-step process,in which metallic zinc films were first deposited by magnetron sputtering, and then oxidized in air to form ZnO. X-ray diffraction spectra show that the films prepared by the reactive magnetron sputtering are of better crystalline quality and show higher c-axis orientation,while the films obtained by the oxidation of the metallic zinc films in the air are randomly oriented. No photoconductive phenomenon was observed for the first set of films, however, the second set of films show remarkable photoconductance. Further analysis shows that the process of absorption and desorption of the oxide gases such as oxygen is the main reason ruslting in the photoconductance of the second group.