Patents by Inventor Guhua Yao

Guhua Yao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Ultra low silicon loss high dose implant strip
    Patent number: 9564344
    Abstract: Improved methods for stripping photoresist and removing ion implant related residues from a work piece surface are provided. According to various embodiments, plasma is generated using elemental hydrogen, a fluorine-containing gas and a protectant gas. The plasma-activated gases reacts with the high-dose implant resist, removing both the crust and bulk resist layers, while simultaneously protecting exposed portions of the work piece surface. The work piece surface is substantially residue free with low silicon loss.
    Type: Grant
    Filed: May 26, 2015
    Date of Patent: February 7, 2017
    Assignee: Novellus Systems, Inc.
    Inventors: David Cheung, Haoquan Fang, Jack Kuo, Ilia Kalinovski, Zhao Li, Guhua Yao, Anirban Guha, Kirk J. Ostrowski