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:
Oct. 21, 2003
Filed:
Apr. 06, 2001
Tong-Hsin Lee, Taipei Hsien, TW;
Shih-Chien Hsu, Taiepi, TW;
Chang-Chi Huang, Miaoli, TW;
Cheng-Tung Huang, Kaohsiung, TW;
Sheng-Hao Lin, Hsinchu Hsien, TW;
United Microelectronics Corp., Hsinchu, TW;
Abstract
A method of fabricating a gate oxide layer. A mask layer isformed on a substrate. The mask layer and the substrate are patterned to form a trench in the substrate. A portion of the mask layer is removed to expose the substrate at a top edge corner portion of the trench. An insulation layer is formed to fill the trench and covering the exposed substrate and the remaining mask layer. The insulation layer over the remaining mask layer is removed to expose the mask layer. The remaining mask layer is removed to expose the substrate. The exposed substrate is implanted with ions to reduce the oxidation rate. As a result, the substrate at the top edge corner portion of the trench covered with the insulation layer has an oxidation rate higher than the exposed substrate. The insulation layer over the surface level of the substrate is then removed to expose the substrate at the top edge corner portion of the trench. A gate oxide is formed on the substrate with a thickness larger at the top edge corner of the trench than elsewhere.