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:
Mar. 09, 2004
Filed:
May. 16, 2003
Jean-Louis Sanchez, Escalquens, FR;
Jean-Pierre Laur, Albi, FR;
Hedi Hakim, Merkezchihya, TN;
Patrick Austin, Bonrepos-Riquet, FR;
Jean Jalade, Castanet-Tolosan, FR;
Marie Breil, Toulouse, FR;
Centre National de la Recherche Scientifique, Paris Cedex 16, FR;
Abstract
The invention concerns a variable capacitance capacitor comprising a periodic structure of raised zones ( ) separated by recesses ( ) formed in a type N semiconductor substrate ( ). The walls of the raised zones and the base of the recesses are coated with a conductive layer ( ). The substrate is connected to a first terminal (A) of the capacitor and the conductive layer to a second terminal (B) of the capacitor. At least the base of the recesses or the side of the raised zones comprises type P regions ( ), the pitch of the raised parts being selected so that the space charging zones linked to the type P regions are joined when the voltage difference between said terminals exceeds a predetermined threshold. The zones not comprising type P regions are coated with an insulant ( ) and a highly doped N region ( ) is formed beneath the insulant.