个人信息Personal Information
副教授
硕士生导师
性别:男
毕业院校:东京工业大学
学位:博士
所在单位:物理学院
办公地点:三束实验室2号楼203
联系方式:0411-84708380:8203
电子邮箱:luwenqi@dlut.edu.cn
Effects of Hf buffer layer at the Y-doped HfO2/Si interface on ferroelectric characteristics of Y-doped HfO(2 )films formed by reactive sputtering
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论文类型:期刊论文
发表时间:2018-08-01
发表刊物:CERAMICS INTERNATIONAL
收录刊物:SCIE
卷号:44
期号:11
页面范围:12841-12846
ISSN号:0272-8842
关键字:Hafnium oxide; Ferroelectricity; Buffer layer; TEM
摘要:10 nm-thick ferroelectric (FE) HfO(2 )films with 1.5 mol% yttrium-doping were fabricated by mid-frequency reactive magnetron co-sputtering deposition on bare Si and underlying metal Hf. Yttrium was incorporated into the HfO2 layers by simultaneously sputtering from Y and Hf metal targets under oxygen atmosphere. The effects of interfacial layer on structural and electrical properties of Y:HfO2 films have been systemically studied using high-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD) and electrical measurements. Based on TEM and XRD measurements, the presence of a non-centrosymmetric orthorhombic phase which is responsible for ferroelectricity in yttrium-doped HfO2 (Y:HfO2) films could be detected. As an initial protective layer, the ultra-thin metal Hf (-1 nm) layer covers the silicon surface and prevents the native oxide growth during the deposition and post-annealing process. Results reveal that the thickness of interfacial layer is significantly reduced by deposit a Hf buffer layer and a remanent polarization P-r of up to 14 mu C/cm(2) can be detected in P-V measurement. The strategy of using Hf buffer layer to improve electrical properties of HfO2 film is a feasible method for the fabrication of metal-insulator-semiconductor (MIS) capacitor based on FE-HfO2/Si gate stack.