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. 19, 2005
Filed:
Nov. 27, 2003
Jing-horng Gau, Hsin-Chu Hsien, TW;
Anchor Chen, Hsin-Chu, TW;
Jing-Horng Gau, Hsin-Chu Hsien, TW;
Anchor Chen, Hsin-Chu, TW;
United Microelectronics Corp., Hsin-Chu, TW;
Abstract
A PN-junction varactor includes a first ion well of first conductivity type formed on a semiconductor substrate of second conductivity type. A first dummy gate is formed over the first ion well. A first gate dielectric layer is formed between the first dummy gate and the first ion well. A second dummy gate is formed over the first ion well at one side of the first dummy gate. A second gate dielectric layer is formed between the second dummy gate and the first ion well. A first heavily doped region of the second conductivity type is located in the first ion well between the first dummy gate and the second dummy gate. The first heavily doped region of the second conductivity type serving as an anode of the PN-junction varactor. Second heavily doped regions of the first conductivity type located in the first ion well at one side of the first dummy gate that is opposite to the first heavily doped region and at one side of the second dummy gate that is opposite to the first heavily doped region, the second heavily doped regions being electrically connected to each other and serving as a cathode of the PN junction varactor.