HfO2-assisted SiO2 reduction in HfO2/SiO2/Si stacks

被引：8

作者：

Li, Xiuyan ^{[1
]}

Yajima, Takeaki ^{[1
]}

Nishimura, Tomonori ^{[1
]}

Nagashio, Kosuke ^{[1
]}

Toriumi, Akira ^{[1
]}

机构：

[1] Univ Tokyo, Dept Mat Engn, Tokyo 1138656, Japan

来源：

THIN SOLID FILMS | 2014年 / 557卷

关键词：

SiO2; reduction; Ultra-high vacuum; SiO desorption; Silicidation; Oxygen vacancies; GATE; DECOMPOSITION; INTERFACE;

D O I：

10.1016/j.tsf.2013.10.142

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The ultra-thin SiO2 interface layer (SiO2-IL) in the HfO2/SiO2/Si stack was found to be reduced during the ultra-high vacuum (UHV) annealing. Along with thin SiO2-IL reduction in UHV, SiO desorption and silicide formation also took place. The thermal desorption spectroscopy and X-ray photoelectron spectroscopy results showed that the SiO2-IL reduction occurred at temperatures lower than the temperature showing SiO desorption and silicidation by accurately controlling the annealing conditions. The mechanism of SiO2-IL reduction can be explained by the oxygen diffusion through oxygen vacancies in HfO2 generated in the gate stack formation and thermal treatment. It is also understandable that the silicidation process is associated with the inhomogeneous SiO desorption. (c) 2013 Elsevier B. V. All rights reserved.

引用

页码：272 / 275

页数：4

共 16 条

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