Fabrication of polymer composite films with carbon composite nanofibers doped MWNTs-OH for multilevel memory device application

Novel carbon composite nanofibers with hierarchical microstructure were synthesized using electro-spinning and carbonization (SC) techniques, and were combined into polyimide matrix based on in-situ polymerization method. The resulted polyimide composites exhibit multilevel resistive switching behavior (MRSB) for memory storage applications, with a favorable ON/OFF current ratio and a high retention time at an operating voltage less than 3 V. A hierarchical microstructure can be observed by SEM, TEM and SAXS tests, which was formed with different sizes between the hydroxyl multi-walled carbon nanotubes (MWNTs-OH), carbon nanofibers and PI matrix, influencing on the MRSB of the composite films. A physical model based on the molecular orbit energy level was utilized to investigate how the microstructures acting as charge transmission layers affect the MRSB. This result provides a new strategy for further improving the high density storage of polymer multilevel switching memory storage device.