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. 04, 1995
Filed:
May. 31, 1994
Hsiao-Chin Tuan, Hsinchu, TW;
Hu H Chao, Hsinchu, TW;
ETRON Technology Inc., Hsinchu, TW;
Industrial Technology Research Institute, Hsinchu, TW;
Abstract
A method of forming a silicon oxide isolation region on the surface of a silicon wafer consisting of a thin layer of silicon oxide on the wafer, a layer of impurity-doped polysilicon, and a layer of silicon nitride. The oxidation mask is formed by patterning the silicon nitride layer and at least a portion of the doped polysilicon layer. The silicon oxide field isolation region is formed by subjecting the structure to a thermal oxidation ambient. The oxidation mask is removed in one continuous etching step using a single etchant, such as phosphoric acid which etches the silicon nitride and polysilicon layers at substantially the same rate to complete the formation of the isolation region without pitting the monocrystalline substrate.