Filamentary resistance switching in phthalocyanine thin films observed by electroluminescence

Metal phthalocyanine heterojunctions with highly stable resistance switching characteristics have been prepared and the switching mechanism has been further investigated by electroluminescence (EL). The point-like EL emission has been observed during switching, demonstrating that the filamentary conduction gives rise to resistance switching. Furthermore, the high correlativity between EL emission sites and domain boundaries of phthalocyanine films has been established, which indicates that the switching process is favorable to occur within the disordered region of organic films. A band-based model has been proposed to describe the EL associated electrical switching mechanism.