Preparation
4-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.
Chemical Properties
Colorless liquid
Uses
Benzocyclobutene 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.
Uses
Benzocyclobutene (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.
Definition
ChEBI: A carbobicyclic compound that is benzene fused to a cyclobutane ring.
Synthesis Reference(s)
Journal of the American Chemical Society, 97, p. 5600, 1975
DOI: 10.1021/ja00852a057The Journal of Organic Chemistry, 38, p. 3412, 1973
DOI: 10.1021/jo00959a039Tetrahedron Letters, 16, p. 1893, 1975
Toxics Screening Level
The Initial Threshold Screening Level (ITSL) for benzocyclobutene is 220 μg/m3 with an annual averaging time.
