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. 26, 2001
Filed:
Jul. 11, 1999
Edwin Arthur Chandross, Murray Hill, NJ (US);
Valerie Jeanne Kuck, Upper Montclair, NJ (US);
Agere Systems Guardian Corp., Orlando, FL (US);
Abstract
An improved siloxane-based composition for use as a low &kgr; dielectric material in integrated circuit applications is provided, the composition exhibiting desirable thermal mechanical stability compared to conventional siloxane-based low-&kgr; compositions. Specifically, the invention provides a modified methylsilsesquioxane composition suitable for higher temperature applications than a composition formed from only methylsilsesquioxane. The modified oligomer is characterized by the pendant group ratio A:B:C, where A represents the percentage of pendant groups that are methyl and is about 13 to about 67, B represents the percentage of pendant groups that are dimethyl and is greater than 0 to about 33, and C represents the percentage of pendant groups that are phenyl and is greater than 0 to about 67. The presence of dimethyl and phenyl pendant groups provides a molecular structure that has improved crack-resistance compared to an all-methyl silsesquioxane. Advantageously, the modified methylsilsesquioxane oligomer is fabricated by a particular technique, involving mixing methyltriethoxysilane monomer, before hydrolysis and condensation, with dimethyldiethoxysilane monomer that has already been partially hydrolyzed and condensed. This technique further improves the thermal mechanical stability of the resultant cured material. For low &kgr; integrated circuit application, a pore generator material is advantageously used to provide a porous final structure.