Abstract: A method of forming an air gap within a semiconductor structure by the steps of: (a) using a sacrificial polymer to occupy a space in a semiconductor structure; and (b) heating the semiconductor structure to decompose the sacrificial polymer leaving an air gap within the semiconductor structure, wherein the sacrificial polymer of step (a) is a copolymer of styrene or styrene derivative (such as alpha methyl styrene) and vinylbenzocyclobutene or a vinylbenzocyclobutene derivative. In addition, a semiconductor structure, having a sacrificial polymer positioned between conductor lines, wherein the sacrificial polymer is a copolymer of styrene or styrene derivative and vinylbenzocyclobutene or a vinylbenzocyclobutene derivative.

Abstract: The invention is a photoswitchable benzocyclobutene-based polymer that while remaining aqueous developable, avoids the problem of significant moisture uptake. The oligomer or polymer comprises a polymeric backbone, benzocyclobutene reactive groups, and photoswitchable pendant groups. The pendant groups are bonded to the polymeric backbone and are characterized by the presence of a moiety that converts to carboxylic acid upon exposure to activating wavelengths of radiation a carboxylic acid. When the oligomer or polymer is subsequently heated to cause cure of the oligomer or polymer, carbon dioxide is emitted and the group forms a substantially non-polar moiety. The invention is also a method of making such a polymer and a method of forming a patterned film using such a polymer.