[16p-P5-1~17] 12.2 Characterization and Materials Physics

▲ [16p-P5-5] Band Bending induced by MoO3 at Organic-Organic Interface

〇(D)Alexandre Foggiatto¹, Takeaki Sakurai¹ (1.Univ. of Tsukuba)

Keywords:Organic Semiconductor, Band Bending, UPS

Recently, one cascade heterojuntion solar cell has received much attention, it was reported that it was achieved an power conversion efficiency of 8.4%, using as acceptor boron subphthalocyanine chloride (SubPc) and boron subnaphthalocyanine chloride (SubNc), which are highly polar molecules, with α-sexithiophene (6T) donor. The study of the molecular level alignment for these materials has already been reported in the literature, however the substrate used was p-doped silicon. In this work, it was analyzed the energy-level alignment of SubPc and 6T deposition on molybdenum trioxide (MoO3), which is commonly used as hole layer transportation in organic photovoltaic devices, using ultraviolet photoelectron spectroscopy (UPS). It was observed that owing to the high work function of MoO3, it was induced a band bending p-doping at the interface with 6T that causes a charge transfer between the 6T and the gap states of SubPc. Unlike the case with silicon substrate, the deposition of MoO3 layer, induces an energy shift towards a lower energy in the SubPc thin film interface region, characterizing an upward band bending.