Background for High-K Gate

Silicon dioxide (SiO2) has been used to make for the gate of transistor for a long time. As the thickness of SiO2 is becoming thinner, the leakage of current is getting remarkable. According to Misra et al. [1], the leakage current density of 1.2nm–SiO2 gate is beyond 100A/m2 when applies 1V voltage. The situation is not allowed in most of application. However, when applying high-k materials, the capacitor of gate is becoming bigger than SiO2. In the other word, the gate can store more electric charge and the leakage current becomes less. The replacement of the SiO2 gate dielectric by high-k dielectric material is to improve the performance and simultaneously extend the scalability of Si MOSFETs.[2] HfSiO is one of high-k material which has better thermal stability is preferred to replace SiO2.

Posted on 3rd Feb. 2014 by Danyu Li and Saisai Wen

[1]. D. Misra, et al. (2005, Sumer). “High-k Gate Dielectrics” [Online]. Available: http://www.electrochem.org/dl/Interface/sum/sum05/IF08-05_Pg30-34.pdf. [Accessed: Jan. 1, 2014]

[2] Y. Taur, et al., “CMOS scaling into the nanometer regime,” Proc.IEEE, vol. 85, p. 486, Apr. 1997. 

Brief Information about Project 27

Our team is working on the Project 27 which is about high-k gate during the end of the first semester and the first five weeks of the second semester of year 2.

The group is consisted of three members -Danyu Li, Zhaojun Wei and Saisai Wen. All of the members are students form EEE department of University of Liverpool. Dr. Ivona Mitrovic, the supervisor of the project, is going to provide support with our project.

This project is designed to study the properties of high-k gate stack HfSiO (50%Hf), a new material may take the place of SiO₂ during transistors production. There are nine compulsory and one optional tasks are required to be accomplished.

This blog will first introduce the background of the project briefly and then narrate how those tasks are finished. If you have any questions about the project, please do not hesitate to ask us.

Posted by Saisai Wen on 3^rd Feb. 2014