Masataka Miyamura

Interlayer dielectric process for LSI circuits using positive photosensitive polyimide synthesized by block-copolymerization

Photosensitive polyimide is expected as a future interlayer dielectric material in LSI circuits. In this paper, we propose a new interlayer dielectric process using a positive photosensitive polyimide directly synthesized from aromatic dianhydride and aliphatic diamine by block-copolymerization. Photosensitive polyimide solution was prepared with N-methyl-2-pyrrolidone (NMP) solvent. A diazonaphthoquinone PC-5 was used as a photosensitizer. The thin film was spin-coated with changing polyimide concentration and rotation speed. The uniformity of the coated film was achieved less than +/- 0.9 % on a 3-inch wafer of silicon. A 0.5 micrometers line and space pattern was obtained by i-line lithography. The (gamma) value of the contrast was evaluated to 1.05. The dielectric constant of the base polyimide was measured for a thick film by the cavity perturbation method. The values from 2.4 to 3.0 were obtained within the frequency range from 1 GHz to 20 GHz. The break down voltage was measured to be 107 kV/mm without high-temperature heat treatment.

New Deep Uv Dyeable Negative Resist For CCD Micro Color Filter

Several kinds of dyeable negative photoresist materials for CCD micro color filters, developed in our Laboratories, are reported. Quaternary ammonium salt-terminating acrylate-glycidyl methacrylate copolymers with bisazides have been developed as negative working resists. Descriptions on their synthesis, lithographic data and the micro color filter process for these resists are mentioned.