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. 04, 2002
Filed:
Feb. 24, 2000
Le-Tien Jung, Hsinchu, TW;
Po-Hung Chen, Taipei, TW;
United Microelectronics Corp., Hsinchu, TW;
Abstract
A method of forming a triple well structure. A first photoresist layer is formed on a substrate having a first conductive type. A first ion implantation process is performed to form a first well, which has the first conductive type but a dopant concentration of the first well is higher than a dopant concentration of the substrate. The first photoresist layer is baked. A second ion implantation process is performed through the baked first photoresist layer to form a first doped region under the first well. The first doped region has a second conductive type. After removing the first photoresist layer, a second photoresist layer is formed on the substrate. A third ion implantation process is performed to form a second doped region in the substrate around the first well and to form a second well in the substrate. The second doped region and the second well have the second conductive type. The second doped region and the first doped region together surround the first well. The first doped region, the first well, and the second doped region compose a triple well structure.