INVESTIGATION OF POLYIMIDE THIN-FILMS DEPOSITED BY IONIZED CLUSTER BEAM

Ionized cluster beam deposition (ICBD) has been employed to fabricate high-purity crystalline polyimide (PI) thin films. X-ray photoemission spectroscopy, transmission electron microscopy, glancing-incidence X- ray diffraction, and atomic force microscopy studies show that the str ucture and properties of PI films are very sensitive to the deposition conditions such as the cluster acceleration voltage (V-a) and the ion ization voltage (V-e). At optimum conditions of V-a = 800 V and V-e = 200 V, the PI films have a maximum imidization, negligible amount of i mpurity (similar to 1% of isoimide), and a good crystalline structure probably due to the high surface migration energy, and the surface cle aning effect. It was also found that the surface morphology and the ad hesion properties could be improved by ICBD.