Cart (Loading....) | Create Account
Close category search window
 

An Effective Approach for Restraining Galvanic Corrosion of Polycrystalline Silicon by Hydrofluoric-Acid-Based Solutions

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

5 Author(s)
Yunfei Liu ; Inst. of Semicond., Chinese Acad. of Sci., Beijing, China ; Jing Xie ; Mingliang Zhang ; Jinling Yang
more authors

This paper presents an effective method to restrain galvanic corrosion of polycrystalline silicon (polysilicon) that is electrically coupled with noble metals of microelectromechanical systems (MEMS) devices by hydrofluoric-acid (HF)-based solutions. A titanium (Ti) redox sacrificial layer is added on the noble-metal layer and then covered by photoresist. Benefiting from the lower electrochemical potential of Ti than that of polysilicon in HF-based solutions, Ti is preferentially corroded in HF-based solutions, and the polysilicon is well protected. The thickness of the Ti layer should be optimized for effectively suppressing galvanic corrosion of polysilicon; a 50-nm-thick Ti film is able to preserve the resistivities of polysilicon unchanged in concentrated HF (49% HF by weight percent) solution for 1 h. This approach is simple and compatible with MEMS batch-fabrication technology and provides a solution for the longstanding issue in microfabrication technology, i.e., galvanic attack to the polysilicon structural layer by HF-based solutions.

Published in:

Microelectromechanical Systems, Journal of  (Volume:20 ,  Issue: 2 )

Date of Publication:

April 2011

Need Help?


IEEE Advancing Technology for Humanity About IEEE Xplore | Contact | Help | Terms of Use | Nondiscrimination Policy | Site Map | Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest professional association for the advancement of technology.
© Copyright 2014 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.