ZnO薄膜肖特基二极管的研制

采用直流反应磁控溅射的方法,在Al/Si(100)衬底上沉积了ZnO晶体薄膜.利用Al和Pt作为与ZnO接触的欧姆电极与肖特基电极,制作了ZnO薄膜肖特基二极管.X射线衍射测试结果表明ZnO薄膜具有高度的c轴择优取向.原子力显微分析表明:样品表面光洁平整,晶粒尺寸约100nm,扩展电阻分析表明ZnO薄膜的厚度为0.4μm,载流子浓度为1.8×1015 cm-3,此后的霍尔测试证实了这一结果并说明ZnO的导电类型为n型.室温下的I-V测试显示ZnO肖特基二极管具有明显的整流特性.Pt与n型ZnO接触的势垒高度为0.54eV.文中的ZnO肖特基二极管为首次研制的原型器件,其性能可以通过器件结构与制作工艺的进一步优化而得到改善.

Preparation of ZnO Thin Film Schottky Barrier Diode

The ZnO thin film has been deposited on Al/Si (100) substrated by direct current (DC) reactive magnetron sputtering method. The ZnO Schottky Barrier Diode (SBD) has been fabricated using Al and Pt as ohmic and Schottky contacts, respectively. X-ray diffraction (XRD) measurement indicated that the ZnO thin film was well c-axis oriented. The atomic force microscope (AFM) showed that ZnO thin film had a smooth surface and the grain size was about 100 nm. The spreading resistance profile (SRP) indicated that the thickness and carrier concentration of ZnO film was 0.4 μm and 1.8×1015 cm-3, respectively. The Hall effect measurements showed that ZnO thin film was of n-type conductivity. The current-voltage measurements indicated and evident rectifying characteristic of ZnO SBD. The barrier height between Pt and n-type ZnO was 0.54 eV. This is the first attempt toward ZnO thin film SBD, which has not been reported before and the performance of the ZnO SBD could be improved by optimizing the device structure and technology.