Interfacial electronic structure of copper hexadecafluorophthalocyanine and phthalocyanatotin (IV) dichloride studied by photoemission spectroscopy

We investigated the interfacial electronic structure of the n-n isotype organic heterojunction formed between copper hexadecafluorophthalocyanine (F16CuPc) and phthalocyanatotin (IV) dichloride (SnCl2Pc) using ultraviolet and x-ray photoemission spectroscopies. Energy level bending was observed at the heterojunction interface due to the formation of an electron accumulation region in the F16CuPc layer and an electron depletion region in the SnCl2Pc layer. The formation of organic heterojunction was explained by charge exchange at the interface due to their different work functions.