Yusuke SATO, Kumiko YAMAGISHI and Masafumi YAMASHITA^*

Department of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan

(Received October 1, 2004; Accepted June 3, 2005)

The optical and electrical characteristics of heterojunction organic photovoltaic cells consisting of tin–phthalocyanine as a p-type semiconductor and fullerene as an n-type semiconductor were studied using multiple-layer structures incorporating two hetero-junctions. In order to prevent formation of a reverse heterojunction, an ultra-thin layer of Au clusters was set between dual heterojunctions. The power conversion efficiencies of the cells were evaluated and the efficiency of the cell with two incorporated heterojunctions was found to be 4.5 times greater than that of a single hetero-junction. By using surface plasmon polaritons, the power conversion efficiency of an Al/C₇₀/SnPc/Au cell was enhanced and increased by a factor of 3.

Key words: tin–phthalocyanine, fullerene, photovoltaic cell, multiple-layer cell, surface plasmon polaritons, attenuated total reflection

^*E-mail address: yamasita@ph.noda.tus.ac.jp