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:
Jul. 14, 1998
Filed:
Jul. 31, 1997
Li-Ming Wang, Ping Tung, TW;
Vanguard International Semiconductor Corporation, Hsinchu, TW;
Abstract
A method for coating a semiconductor wafer with a high-viscosity photoresist that requires a seven-phase coating process which uses a large diameter dispenser nozzle is disclosed. In this first phase, the photoresist is dispensed onto a slow rotating wafer. In the second phase, this slow rotation phase is continued for a short time after the photoresist is dispensed. In the third phase, the wafer rotational speed is increased to a second value for a short duration. In the fourth phase, the rotational speed is again increased to a third high value for a long duration. In the fifth phase, the rotational speed is decreased to a fourth value and the backside of the wafer is rinsed for a short time period to remove any photoresist that may have migrated to the backside. In the sixth phase, the wafer is rotated at the fourth speed value for another short time period. Finally, the rotation of the wafer is stopped for about a second before being removed from the photoresist coating system.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile