机构地区: 杭州电子科技大学电子信息学院
出 处: 《材料科学与工程学报》 2010年第1期5-7,共3页
摘 要: 利用溶胶-凝胶法制备了Zn1-xMgxO压敏薄膜,并通过X射线衍射、X射线能谱、紫外-可见光谱仪、I-V特性测试仪等对薄膜及其压敏特性进行了表征。XRD结果表明,掺Mg后Zn1-xMgxO薄膜仍然为六方纤锌矿ZnO晶体结构;紫外-可见吸收谱表明,随着薄膜中Mg含量的增加,薄膜的吸收边蓝移,禁带宽度增加。I-V特性曲线表明,基于Al/Zn1-xMgxO/Si结构的薄膜压敏电阻器的阈值电压随着Mg含量的增加而增加,因此可以通过调节Mg含量实现对Zn1-xMgxO薄膜压敏电阻器阈值电压的调节。上述现象表明,Zn1-xMgxO薄膜压敏电阻器的压敏阈值电压与禁带宽度有关,即与Zn1-xMgxO薄膜中电子的本征跃迁有关。 Zn1-xMgxO thin films were deposited by sol-gel method and characterized by X-ray diffraction,X-ray energy dispersive spectrum,UV-Visible absorbance,and I-V curve test.Experimental results showed Zn_(1-x)Mg_xO thin films are of hexagonal wurtzite structure as undpoed ZnO thin films.The absorption edge of the Zn_(1-x)Mg_xO shows blue-shift,and which in turn increases the bandgap of the Zn1-xMgxO thin films as Mg content increases.I-V test of the Varistors made of Al/ Zn1-xMgxO/Si shows increased threshold voltage as the Mg content increases,too.Therefore,it is possible to tune the varistors threshold to a required value by controlling the Mg content.The correlation between the threshold of the varisotros and the bandgap of the Zn_(1-x)Mg_xO thin films indicates that intrinsic transition of electrons in Zn_(1-x)Mg_xO thin films is the dominant factor for the mechanism of such thin film varistors.