MSM结构ZnO/Cu薄膜的接触特性

Contact Properties of ZnO/Cu Films with MSM Structure

利用脉冲激光沉积(PLD)法在Si(111)衬底上分别生长了ZnO薄膜和Cu薄膜,用Cu薄膜作电极,研究了ZnO薄膜与Cu薄膜的接触特性。分别用X射线衍射仪、扫描电子显微镜和I-V测试的方法对样品的晶体质量、结构和电学性质进行了测试。结果表明:样品中ZnO薄膜和Cu薄膜均具有高度的择优取向;当Cu和ZnO直接接触时,样品的I-V特性是非线性的;当Cu和ZnO之间通过ZnO∶Cu层间接接触时形成良好的欧姆接触,而且退火后欧姆接触性能明显提高,电阻率降低约2/3。本研究为价格低廉的Cu电极成为ZnO基器件的欧姆电极提供了一定的依据。

Considering the good conductivity and anti-electromigration and low price, Cu films were prepared as electrodes of ZnO-based devices via pulsed laser deposition method on Si （ lll） sub- strates. The XRD and SEM images of ZnO/Cu films were examined and the current-voltage charac- teristics were measured. The results exhibit that ZnO films are highly c-axis oriented, and Cu films are highly （ 111 ） oriented. Ohmic contact can be obtained when the ZnO： Cu layer was involved between the ZnO film and the Cu film, and the Ohmic contact properties can be improved after annealing. Study on how to improve the properties of Ohmic contact of the ZnO/Cu films is still continued. The results indicate that Cu may be used as Ohmic contact electrodes for ZnO-based devices.