Investigations of Band Alignment at Interfaces of Au/Polypropylene and Au/Polyimide

As charge injection from metal into dielectric polymer causes degradation and breakdown of electronic and power devices, the band alignment at the metal/polymer interface should be revealed. To investigate the dominant factors of the band alignment at the metal/polymer interface, we carried out a combined experimental and first-principles computational study. We examined Au/polypropylene (PP) interface and Au/polyimide (PI) interface. PP and PI were chosen as a model system for nonpolar and polar polymers, respectively. The results imply that the band alignment can be determined under the assumption that vacuum levels of metal and polymer match at the interface regardless of the dipole moment of polymers. © 2023 The Institute of Electrical Engineers of Japan.