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. 25, 1990
Filed:
Nov. 25, 1988
Applicant:
Inventors:
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ; B08B / ;
U.S. Cl.
CPC ...
437 10 ; 437-9 ; 437946 ; 134-1 ;
Abstract
When a surface of semiconductor wafer is treated for gettering, ultrasonic waves are caused to propagate along the surface of the semiconductor wafer, through pure water. Mechanical damages are formed on the surface of the semiconductor wafer along which the ultrasonic waves propagated, the damages serving as a back side damage.