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:
Sep. 13, 2005
Filed:
Jul. 17, 2002
Shin-rung LU, Hsin-Chu, TW;
Ho-ku Lan, Jubei, TW;
Shin-Rung Lu, Hsin-Chu, TW;
Ho-Ku Lan, Jubei, TW;
Taiwan Semiconductor Manufacturing Company, Hsin-Chu, TW;
Abstract
A method is provided for forming features in a polyimide layer that is employed as an insulating layer or buffer layer during the fabrication of semiconductor devices or chip packaging structures. A pattern is formed in a photosensitive layer that has a high film retention after the development step and a crosslinked network that strengthens and stabilizes it for subsequent processing. The process involves exposing a negative tone photosensitive layer with a first exposure dose that is less than the normal dose used to image the material. The exposed layer is developed to provide a scum free substrate. A second exposure dose then strengthens the formed image by crosslinking unreacted components. First and second exposure doses are determined from a plot of film thickness loss vs. exposure energy. The method applies to photosensitive polyimide precursors as well as negative photoresists that are crosslinked by free radical or chemical amplification mechanisms.