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:
May. 22, 2001
Filed:
Mar. 29, 1999
Kuan-Yang Liao, Taipei, TW;
United Microelectronics Corp., Hsinchu, TW;
Abstract
A method for manufacturing a MOS device with multiple threshold voltages is provided. The method comprises providing a substrate. A shallow trench isolation structure is formed in the substrate. The top surface of the shallow trench isolation structure is higher than surface of the substrate. An active region which is surrounded by the shallow trench isolation structure is defined in the substrate. A first process of ion implantation is performed on the substrate except a portion of the substrate under the shallow trench isolation structure. A first spacer is formed on the sidewall of a portion of the shallow trench isolation structure above the substrate in the active region. A second process of ion implantation is performed on the substrate except a portion of the substrate under the shallow trench isolation structure and the first spacer.