Benzocyclobutene

UsesBenzocyclobutene (BCB) is composed of a benzene ring fused to a cyclobutane ring (chemical formula C8H8). It is frequently used to create photosensitive polymers. BCB-based polymer dielectrics may be spun on various substrates, with good step coverage properties that make them useful to planarize uneven topographies. Applications include wafer bonding, optical interconnects, semihermetic package sealing, passivation, and low-k dielectrics. BCB has been also reported as a material with good biocompatibility, being used in intracortical neural implants and other biomedical applications.

UsesBenzocyclobutene was used as the adhesive bonding material in adhesive wafer-level bonding technique. Photosensitive benzocyclobutene has been widely used as dielectric material in multilayer packaging applications. It was used in fabrication of high density multilayer interconnect structures using gold metallization and polymer interlayer dielectric.

Preparation4-Bromobenzocyclobutene, a catalyst, magnesium or zinc metal, and a solvent are mixed and stirred at 20–50°C for 0.2–2 h under an inert gas atmosphere. After the reaction is completed, the reaction solution is separated to obtain benzocyclobutene. The catalyst is nickel chloride, titanium chloride, Fe(acac)3, or benzoyl acetophenone iron.