Optical and electrical properties of isotype crystalline molecular organic heterojunctions

摘要: We have studied the electrical and optical characteristics of isotype p‐P organic heterojunctions (HJ) consisting CuPc (copper phthalocyanine) PTCDA (3,4,9,10‐perylenetetracarboxylic dianhydride). It is found that charge‐transport properties heterojunction are limited by thermionic emission holes over energy barrier at CuPc/PTCDA low forward reverse bias, series resistance high voltage. The valence‐band edge was measured using both current‐voltage capacitance‐voltage analysis to be ΔEvC,P=0.48±0.05 eV. Similar measurements made for HJs in combination with another perylene‐based material, 3, 4, 9, 10‐perylenetetracarboxylic‐bis‐benzimidazole (PTCBI), suggest band offsets these three materials follow a transitive relationship. That is, ΔEvC,P=ΔEvC,B−ΔEvB,P, where subscripts C, P, B refer CuPc, PTCDA, PTCBI, respectively. resul...