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:
Oct. 08, 2002
Filed:
Oct. 29, 1999
Boris Fishkin, San Carlos, CA (US);
Alexander Lerner, San Jose, CA (US);
Jianshe Tang, Cupertino, CA (US);
Brian J. Brown, Palo Alto, CA (US);
Applied Materials, Inc., Santa Clara, CA (US);
Abstract
A Megasonic cleaning apparatus having at least one reflector (e.g., a parabolic or paraboloid reflector) positioned to collect otherwise wasted cleaning energy and redirect that energy to one or a plurality of positions on a wafer's edge is provided. A first embodiment comprises a complex parabolic reflector which has a width greater than that of the wafer and a preferred length approximately equal to the diameter of the wafer, and which is shaped to provide focal points which vary along the length of the parabolic reflector, such that energy striking the reflector at different points along the reflector's length is directed to a plurality of different points along the wafer's edge. A second embodiment comprises a simple parabolic reflector having a width greater than that of the wafer and a preferred length less than the diameter of the wafer, and which is provided to focus at a cord along the wafer's surface, effectively focusing cleaning energy on two points along the wafer's edge at any given time. Yet another embodiment of the invention comprises a paraboloid reflector having a width greater than that of the wafer and a preferred length which is substantially less than the diameter of the wafer and which is shaped to focus all collected energy to a single point on the wafer's edge. Multiple such reflectors may be positioned in the cleaning tank to optimize energy usage and wafer cleaning.