磁控溅射法制备高性能ZnO薄膜晶体管

Preparation of high-performance ZnO thin-film transistors by magnetron sputtering method

研究了磁控溅射法制备的ZnO薄膜晶体管(TFT)。以NH3处理的热生长SiO2作为绝缘层,控制好Ar-O2比等条件溅射合适厚度的ZnO作为器件的有源层。实验表明,与普通条件下热生长的SiO2绝缘层硅片相比,NH3处理的高性能SiO2绝缘层Si片器件的载流子迁移率至少要高1个数量级以上;溅射条件在Ar-O2比25∶1情况下制作的器件性能最好;ZnO薄膜厚度也对ZnO-TFT性能有很大的影响。实验中,采用了4种膜厚,测试表明,其中25nm厚的ZnO薄膜迁移率最大。

ZnO thin-film transistors（TFTs） prepared by magnetron sputtering method are investigated.The thermal growth SiO2 treated with NH3 is the device′s insulator layer,and the appropriate-thickness ZnO sputtered with fine Ar-O2 ratio is the device′s active layer.The results suggest that the device carrier mobility where SiO2 is treated with NH3 is at least one order of magnitude higher than that of the thermal growth SiO2 device.The optimal Ar-O2 ratio is 25∶1.The ZnO film thickness has great influence on the ZnO-TFT device performance.Four film thicknesses are selected,and the results indicate that 25 nm-thick ZnO films have the maximum mobility.