The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 25, 2015
Filed:
May. 23, 2012
Alice Hollister, Tigard, OR (US);
Sirish Reddy, Hillsboro, OR (US);
Keith Fox, Tigard, OR (US);
Mandyam Sriram, Beaverton, OR (US);
Joe Womack, Tigard, OR (US);
Alice Hollister, Tigard, OR (US);
Sirish Reddy, Hillsboro, OR (US);
Keith Fox, Tigard, OR (US);
Mandyam Sriram, Beaverton, OR (US);
Joe Womack, Tigard, OR (US);
Novellus Systems, Inc., Fremont, CA (US);
Abstract
Smooth silicon films having low compressive stress and smooth tensile silicon films are deposited by plasma enhanced chemical vapor deposition (PECVD) using a process gas comprising a silicon-containing precursor (e.g., silane), argon, and a second gas, such as helium, hydrogen, or a combination of helium and hydrogen. Doped smooth silicon films and smooth silicon germanium films can be obtained by adding a source of dopant or a germanium-containing precursor to the process gas. In some embodiments dual frequency plasma comprising high frequency (HF) and low frequency (LF) components is used during deposition, resulting in improved film roughness. The films are characterized by roughness (Ra) of less than about 7 Å, such as less than about 5 Å as measured by atomic force microscopy (AFM), and a compressive stress of less than about 500 MPa in absolute value. In some embodiments smooth tensile silicon films are obtained.