New Approach for Fabricating of Deep Submicron Free-Standing Polyimide Thin Film

Abstract

A new approach for manufacturing ultrathin free-standing polyimide film was proposed. This approach involves casting polyamic acid solution to a Al-doped zinc oxide film coated substrate sputtered at room temperature and to form polyamic acid film. The polyamic acid film was released from substrate in 0.5% diluted hydrochloric acid. Then polyamic acid was reattached to glass substrate and was transformed into polyimide film by thermal imidization with gradient heat treatment process. After that, thickness of the1000 nm polyimide film was reduced by KrF excimer laser ablation with 100 pulses at 45 mJ/cm2 and 30 pulses at 75 mJ/cm2, and 200 nm free-standing polyimide film was obtained. By this method, free-standing polyimide films of 1000 nm and 200 nm thickness were fabricated without and with excimer laser ablation reduction, respectively.