Electroreduction of aromatic imines in the presence of electrophiles gave the corresponding inter- and intramolecular coupling products when the reaction was carried out with the use of chlorotrimethylsilane (CTMS) as the trapping agent of an anion intermediate.

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A plasma-enhanced co-polymerization technique was developed for low-k/Cu damascene integration on 300 mm wafers. This technique enables us to control dielectric film properties by introducing organo-siloxane and hydrocarbon into a He-plasma. The growth rate of the low-k film derived from divinyl siloxane–benzocyclobutene (DVS–BCB) as a matrix monomer is increased by adding C2H2 as a deposition acceleration monomer and the Young's modulus was enhanced by adding diisopropenylbenzene (DIPB) or divinylbenzene (DVB) as a reinforcement monomer. Cu damascene interconnects with plasma polymerized low-k films were successfully fabricated on 300 mm wafers.

We have demonstrated that the mechanical strength of organic silica low-k films can be enhanced by introducing a reinforcement monomer in a matrix monomer under plasma excitation. The modulus improvement mechanism was investigated by analyzing the film structure. Pyrolysis gas chromatography /mass spectrometry (Py-GUMS) revealed incorporation of a reinforcement monomer in the matrix through co-polymerization reactions. Compositional analysis of the films showed that the extent of reinforcement is associated with co-polymerization ratio or the monomer content in the film. It is also indicated that the modulus enhancement depends on the content of 3-dimensional aromatic bridged structure, which is affected by the chemical structure of the reinforcement monomers.

Vapor phase reactions in plasma polymerization of divinylsiloxane-bis-benzocyclobutene (DVS-BCB) low-k film depositions on 300mm wafers were studied using mass spectrometry, in situ Fourier transform infrared, and a surface wave probe. Polymerization via Diels-Alder cycloaddition reaction was identified by the detection of the benzocyclohexene group. Hydrogen addition and methyl group desorption were also detected in DVS-BCB monomer and related large molecules. The dielectric constant k of plasma polymerized DVS-BCB with a plasma source power range up to 250W was close to ∼2.7 of thermally polymerized DVS-BCB, and increased gradually over 250W. The electron density at 250W was about 1.5×1010cm−3. The increase of the k value at higher power was explained by the decrease of both large molecular species via multistep dissociation and incorporation of silica components into the polymer. It was found that the reduction of electron density as well as precursor residence time is important for the plasma polymerization process to prevent the excess dissociation of the precursor.