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:
Dec. 12, 2000
Filed:
Jul. 20, 1999
Michael B Olesen, Yorba Linda, CA (US);
Mario E Bran, Garden Grove, CA (US);
Other;
Abstract
Semiconductor wafers are positioned in a cleaning tank and subjected to sequential flows of one or more highly diluted cleaning solutions that are injected into the lower end of the tank and allowed to overflow at the upper end. One solution comprises one part ammonium hydroxide, two parts hydrogen peroxide, and 300-600 parts deionized water together with a trace of high purity surfactant. Rinsing water is flowed through the tank after the first solution is dumped. A second solution comprises highly dilute hydrofluoric acid. A third solution is more dilute than the first solution. A fourth solution contains hydrochloric acid greatly diluted with deionized water. The solutions are initiated either by injecting the chemicals into an incoming DI water line or directly into the tank. The cleaning tank is provided with a megasonic generator in its lower portion for selective application of megasonic energy. Quick dump valves in the tank bottom enable the solutions to be quickly dumped followed by one or more rinse steps, including a quick refill while spraying and then dumping of the rinsing water.