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:
Jul. 10, 2001
Filed:
Jan. 22, 1999
United Microelectronics Corp., Hsinchu, TW;
Abstract
The invention provides a method of forming shallow trench isolation. In the method, a first mask and a second mask layer are made of polysilicon and silicon oxide, respectively. Part of the first mask layer is oxidized into a protective oxide layer during thermal oxidation for forming a liner oxide layer. The protective oxide layer can protect the top corner of a trench from he formation of pits during subsequent etching for removing a pad oxide layer, thereby preventing a kink effect. Furthermore, after forming the liner oxide layer and before filling the trench with an insulting layer, a buffer layer formed over a substrate not only prevents the sidewalls of the trench from oxidizing, but also prevents a lateral etching damage during subsequent etching for removing the pad oxide layer.