Jun 27 2007
FSI International, Inc. announced that it received Notice of Allowance from the U.S. Patent and Trademark Office for a surface preparation method of forming an ultra-thin silicon oxide layer required prior to deposition of a high dielectric constant (high-k) film. This patent broadens FSI’s technology portfolio to further address the needs of IC manufacturers when implementing high-k technology in the fabrication of 45nm and 32nm devices.
A very thin (less than five angstroms) and very uniform silicon oxide film is required prior to the deposition of the high-k film, but this is difficult to achieve with traditional processes. FSI’s new method achieves a silicon oxide film that is both thin and uniform. This new method is an oxide growth and etch-back process best performed with FSI’s SymFlow® HF etch and surface tension gradient (STG®) rinse/dry technologies in a single tank using the FSI MAGELLAN® Immersion Cleaning System.
For successful implementation of high-k technology, IC manufacturers also require selective removal of the high-k dielectric film from the source and drain regions after patterning the gate materials. FSI’s previously patented wet etch technology provides customers with an effective method for removing high-k films with excellent selectivity. This high-k wet etching technology is available in both the MAGELLAN® System and the FSI ZETA® Spray Cleaning System. More information on this patented technology is found on the FSI web site at http://www.fsi-intl.com/press/2005/feb_15_2005.php.
“This new method, in combination with FSI’s other high-k selective etching method, allows us to supply customers with effective solutions for advanced gate stack fabrication,” said Jeffery W. Butterbaugh, FSI’s chief technologist. “Moreover, this allowed patent further strengthens our surface conditioning IP portfolio and deepens our commitment to continue providing innovative technology to meet the challenges of this rapidly advancing industry.”