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:
Jun. 10, 1997
Filed:
Jan. 03, 1996
Chang J Lee, Choongchungbook-Do, KR;
Jong K Kim, Choongchungbook-Do, KR;
LG Semicon Co., Ltd., Cheongju, KR;
Abstract
A method for forming wells of a semiconductor device, being capable of removing the topology between n- and p-well regions. The method of the present invention provides a twin well structure wherein the n-well region has a higher level than the p-well region. This method includes the steps of sequentially forming a buffering film and an oxidizable film over a semiconductor substrate, forming an anti-oxidation film over the oxidizable film, removing a portion of the anti-oxidation film disposed at a first well region of the semiconductor substrate, implanting impurity ions in the first well region of the semiconductor substrate and annealing the resulting structure, thereby forming a first well in the substrate, removing the anti-oxide film and the oxidizable film both disposed at a second well region of the substrate, and implanting impurity ions in the second well region of the semiconductor substrate and annealing the resulting structure, thereby forming a second well in the substrate.