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:
Apr. 29, 1997
Filed:
Apr. 14, 1995
Sheng-Hsing Yang, Hsinchu, TW;
United Microelectronics Corporation, Hsinchu, TW;
Abstract
A process for fabricating double well regions for a semiconductor device having a first well region of a first type and a second well region of a second type on the substrate is disclosed. The process comprises the steps of first implanting impurities of the first type into the substrate. Then a shielding layer covering the location designated for the first well region of the first type on the substrate is formed. Impurities of the second type are then implanted into the substrate at locations not covered by the shielding layer and designated for the formation of the second well region of the second type. Finally, the impurities of both the first and the second type are driven into a designated depth of the substrate by a heating process to form the first well region of the first type and the second well region of the second type.