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:
May. 24, 1994
Filed:
Jul. 01, 1991
James C Chien, Amherst, MA (US);
Academy of Applied Science, Inc., Concord, NH (US);
Abstract
A process for forming a polymer (and the polymer formed thereby) for passivation, resist and bonding uses, for example, that is thermally stable at relatively high temperatures in excess of 400.degree. C., but is sensitive to electromagnetic radiation. The process includes forming a heteroatom ring polymer that includes a chain formed of a large number of closed aromatic rings such as polyimide groups. According to the present teaching, intervening moieties, (that is, chemical groupings) in the form of open ring precursors of the aromatic rings, such as polyamic acid groups are introduced between the successive closed aromatic rings, which destroy and/or delimit the colinear character and the coplanar character typical of the successive aromatic rings, thus rendering the aromatic rings sensitive to structural change by electromagnetic radiation exposure, and soluble in common organic solvents, but with the exposed HRP insoluble in resist developers.