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. 11, 2006
Filed:
Jun. 22, 2004
Ted Johansson, Djursholm, SE;
Hans Norström, Solna, SE;
Stefan Sahl, Solna, SE;
Infineon Technologies AG, Munich, DE;
Abstract
A method in the fabrication of an integrated bipolar circuit for forming a p/n-junction varactor is disclosed. The method featuring the steps of providing a p-doped substrate (); forming a buried n-doped region () in the substrate; forming in the substrate an n-doped region () above the buried n-doped region (); forming field isolation () around the n-doped region (); multiple ion implanting the n-doped region (); forming a p-doped region () on the n-doped region (); forming an n-doped contact region to the buried n-doped region (), the contact region being separated from the n-doped region (); and heat treating the hereby obtained structure to set the doping profiles of the doped regions. The multiple ion implantation of the n-doped region (); the formation of the p-doped region (); and the heat treatment are performed to obtain a hyper-abrupt p/n-junction within the n-doped region ().