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:
Jun. 17, 1997
Filed:
Mar. 15, 1996
Sen Fu Chen, Taipei, TW;
Wen Cheng Chang, Tauyuan, TW;
Heng Hsin Liu, Hsin-Chu, TW;
Bao Ru Yang, Hsin-Chu, TW;
Taiwan Semiconductor Manufacturing Company Ltd., Hsin-Chu, TW;
Abstract
A patterned silicon nitride layer formed over a semiconductor integrated circuit wafer having a layer of pad oxide is often used as a mask for subsequent processing steps. Etching of the silicon nitride layer is difficult to control and can create defects in the pad oxide layer which are difficult to detect before the manufacture of the semiconductor integrated circuit wafer is completed. A method is described using potassium hydroxide treatment and scanning electron microscope evaluation of a test wafer for detection of defects at the silicon nitride etching step. Continued processing of defective wafers can be terminated and the silicon nitride etching step can be controlled using this method.