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:
Feb. 25, 2003
Filed:
Dec. 13, 2000
Kenneth C. Struven, San Carlos, CA (US);
Imtec Acculine, Inc., Sunnyvale, CA (US);
Abstract
In a substrate bath that processes substrate wafers using megasonic energy, a tank that is provided with reflecting surfaces that direct the megasonic energy to those portions of the substrates that would otherwise be sonically shadowed by the cassette that supports the substrates. In one aspect, a pair of curved wall surfaces are formed within the tank, each extending from one side wall to the bottom wall in curvilinear fashion and oriented longitudinally, the paired curved wall surfaces being disposed in laterally spaced, enantiomorpic relationship. The curved surfaces are arranged so that a significant amount of the megasonic energy impinges at an angle less than the critical angle, so that the energy is reflected in a diverging field that intersects the substrates and strikes those portions of the substrates that are shadowed by the cassette structure. Thus the megasonic cleaning, (etching or processing of the substrate) process is improved significantly.