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:
Sep. 22, 1998
Filed:
Dec. 29, 1995
James F Buller, Austin, TX (US);
Basab Bandyopadhyay, Austin, TX (US);
Shyam Garg, Austin, TX (US);
Nipendra J Patel, Austin, TX (US);
Thomas E Spikes, Jr, Round Rock, TX (US);
Advanced Micro Devices, Inc., , US;
Abstract
A wafer surface cleaning method is provided comprising immersion of the wafer in a H.sub.2 O:NH.sub.4 OH:H.sub.2 O.sub.2 solution at a temperature less than 65.degree. C. prior to formation of a thin oxide such as a tunnel oxide or gate oxide. Immersion of the wafer in a sub-65.degree. C. NH.sub.4 OH results in a smoother wafer surface that increase the charge-to-breakdown (Q.sub.BD) of the subsequently formed oxide. In the tunnel oxide embodiment, the lower temperature solution also reduces the oxide etch rate of the solution enabling a minimum overgrowth of gate oxide which, in turn, enables the addition of an in situ growth temperature anneal of the gate oxide without altering other process parameters.