High field conduction and breakdown of ultra thin evaporated polypropylene films

The conduction current of an Al/thin PP film/Al structure are explained by tunneling injection and its breakdown strength was about 12 MV/cm without a self-healing breakdown. The surface structures of a conventional PP film and a thin PP film were measured with ESCA, and compared with each other. The degree of oxidation of the thin PP film surface was two times higher than that of a conventional PP film surface. X-ray diffraction studies showed that the thin PP film had high crystallinity and orientation.