The Si/SiO(2) Interface Roughness

The Si/SiO$\sb2$ interface roughness has important effects on the performance of metal-oxide-semiconductor field effect transistor devices, which dominate contemporary integrated circuit technology. There have been intense efforts to study this system due to its importance. In this work, a new transmission electron microscope technique has been developed to study the interface roughness of Si/SO$\sb2$. Interfaces between Si and furnace grown SiO$\sb2$ layers can be unambiguously imaged with this technique, hence rich information on interface roughness can be obtained. The basic principle and related issues of this technique are discussed. The main character of random roughness is also reviewed. With this technique, the effect of post-oxidation annealing on Si(100)/SiO$\sb2$ and Si(111)/SiO$\sb2$ interface roughness has been investigated. It was found that as-grown $\sim$6nm thick silicon(100) dioxides generate a very high roughness (σ \sim 10-15A). However, this roughness can be removed by short annealing in nitrogen at the growth temperature of 900$\sp\circ$C. A growth model for silicon oxidation is proposed to understand this dramatic effect of post-oxidation annealing at the unusually low temperature of 900$\sp\circ$C. Roughness parameters such as correlation length and root-mean-square roughness are related to oxidation rate and diffusion constant in this model. The effect of chemical processing on the starting surface of silicon was also studied. Other related issues such as imaging processing, the experimental set-up and the future directions in this field are also addressed in this dissertation.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Chen, Xidong

Contributors dc:contributor

• Gibson, J. Murray

• Engineering, Materials Science

Language dc:language

eng

Identifier

(MiAaPQ)AAI9812553

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/80646