半导体学报2009，Vol.30Issue(10)：21-26,6.DOI:10.1088/1674-4926/30/10/103003
Leakage current mechanisms of ultrathin high-κEr_2O_3 gate dielectric film
Leakage current mechanisms of ultrathin high-κEr_2O_3 gate dielectric film
摘要
Abstract
A series of high dielectric material Er_2O_3 thin films with different thicknesses were deposited on p-type Si (100) substrate by pulse laser deposition at different temperatures. Phase structures of the films were determined by means of X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). Leakage current density was measured with an HP4142B semiconductor parameter analyzer. The XRD and HRTEM results reveal that Er_2O_3 thin films deposited below 400 ℃ are amorphous, while films deposited from 400 to 840 ℃ are well crystallized with (111)-preferential crystallographic orientation. I-V curves show that, for ultrathin crystalline Er_2O_3 films, the leakage current density increases by almost one order of magnitude from 6.20 × 10~(-5) to 6.56×10~(-4) A/cm~2, when the film thickness decreases by only 1.9 nm from 5.7 to 3.8 nm. However the leakage current density of ultrathin amorphous Er_2O_3 films with a thickness of 3.8 nm is only 1.73×10~(-5) A/cm~2. Finally, analysis of leakage current density showed that leakage of ultrathin Er_2O_3 films at high field is mainly caused by Fowler-Nordheim tunneling, and the large leakage of ultrathin crystalline Er_2O_3 films could arise from impurity defects at the grain boundary.关键词
Er_2O_3/ high-κ gate dielectrics/ leakage current/ leakage current mechanismsKey words
Er_2O_3/ high-κ gate dielectrics/ leakage current/ leakage current mechanisms分类
信息技术与安全科学引用本文复制引用
Wu Deqi,Yao Jincheng,Zhao Hongsheng,Chang Aimin,Li Feng..Leakage current mechanisms of ultrathin high-κEr_2O_3 gate dielectric film[J].半导体学报,2009,30(10):21-26,6.基金项目
Project supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No. 072C201301) and the Graduate Student Innovation Program of the Chinese Academy of Sciences. （No. 072C201301）
