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:
Mar. 28, 2000
Filed:
Oct. 29, 1997
Komatsu Electric Metals Co., Ltd., Kanagawa, JP;
Abstract
It is an object of the present invention to provide a method for efficiently making semiconductor wafers that prevents the production of metal pollution. It is another object of the present invention to provide a method where the back side of the wafer does not influence the front side, thereof, and where the front and back sides of the wafer can be distinguished are polishing. This invention provides a method for efficiently making semiconductor wafers having uniform thickness where the thickness of the back side does not influence the front side and where the front side of the wafer is capable of being distinguished from the back side. A semiconductor ingot is sliced to obtain wafers. The sliced surfaces of the wafers are flattened. The flattened wafer is etched in alkaline etching solution. Both the front and back sides of the etched wafer are polished using a double sided polishing apparatus so that the front side is a mirror surface and an unevenness remains on the back side to distinguish the front and back sides, thereof. The polished wafer is cleaned.