Scientific Research Publishing

Read  full  paper  at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=53662#.VM8paizQrzE Author(s)    Ryoji Maeda 1,2* , Hiroshi Tokairin 2 , Jun-Ichi Takahashi 2 , Yuji Yoshida 1,3   Affiliation(s) 1 Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Japan . 2 Advanced Technology Research Laboratories, Idemitsu Kosan Co., Ltd., Sodegaura, Japan . 3 Research Center for Photovoltaic Technologies, AIST, Tsukuba, Japan . ABSTRACT In-situ impedance spectroscopy (IS) observations of the photoconductivity of the carriers induced by photo-irradiation in organic hetero-junction structured photovoltaic devices are presented. In the IS measurements, the externally applied voltage and the dependence of the light intensity applied to the device were investigated. Analysis of the frequency characteristics which was measured by changing the light intensity shows there is a propor...

Read  full  paper  at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52912#.VKyaicnQrzE Author(s)   Ryoji Maeda 1,2* , Hiroshi Tokairin 2 , Hidetsugu Ikeda 2 , Jun-Ichi Takahashi 2 , Yuji Yoshida 1,3   Affiliation(s) 1 Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Japan . 2 Advanced Technology Research Laboratories, Idemitsu Kosan Co., Ltd., Sodegaura, Japan . 3 Research Center for Photovoltaic Technologies, AIST, Tsukuba, Japan . ABSTRACT The carrier dynamics in organic photovoltaic (OPV) cells were investigated by impedance spectroscopy. We introduced a novel impedance spectrum representation called dynamic modulus plot (DMP), which allowed us to observe the layer-to-layer carrier injection behavior graphically. In this work, the impedance responses were characterized in the N , N ’-diphenyl- N , N ’-di-m-tolyl- 4,4’-diaminobiphenyl (TPD)/C 60 p-n heterostructured...