A Flexible Field Emitter Made by Ion-Beam Modification of Polyimide Film

摘要

We demonstrate the field emission of electrons from an ion-beam modified polyimide material. A polyimide sheet of 25 μm-thick is used as the starting material for a flexible field emitter. The electrical resistivity of polyimide film is found to abruptly decrease after Ar ion irradiation to doses higher than 5x10~(15) cm~(-2). For the field emission, a pyramid-like structure is directly fabricated on the polyimide sheet by using oxygen-plasma etching and Ar ions are irradiated to the pyramid-like structured polyimide. Emission current of the order of μA is observed at relatively low electric field for the irradiated samples, while no emission is detected from unirradiated samples. The emission current stability of 1.9+-0.3 μA is observed at relatively low applied voltage. The characteristics of the irradiation condition and the emission current have been compared with the photoresist (novolac resin).