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, 1999
Filed:
Mar. 11, 1997
Chien-Jung Yang, I-Lan, TW;
Ming-Tsung Lee, Taipei, TW;
United Microelectronics Corporation, Hsin-Chu, TW;
Abstract
This ion implantation method reduces the observed levels of cross-contamination and reduces the level of variations in surface conductivity related to the provision of multiple ion implantations into a semiconductor wafer. Reduced levels of cross-contamination are obtained by purging the implantation chamber and then evacuating the implantation chamber before beginning an implantation process. This purge and evacuation cycle is believed to be particularly effective in reducing cross-contamination when two implantations are made consecutively into a wafer without removing the wafer from the implantation chamber or when successive wafers are transported into the ion implantation chamber and implantations are made into each successive wafer.