In-Situ Measurements of the Photoconductivity of Multi-Layered Organic Photovoltaic Devices Using Impedance Spectroscopy

Ryoji Maeda; Hiroshi Tokairin; Jun-Ichi Takahashi; Yuji Yoshida

doi:10.4236/ampc.2015.52007

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Advances in Materials Physics and Chemis... > Vol.5 No.2, February 2015

In-Situ Measurements of the Photoconductivity of Multi-Layered Organic Photovoltaic Devices Using Impedance Spectroscopy ()

Ryoji Maeda^1,2*, Hiroshi Tokairin², Jun-Ichi Takahashi², Yuji Yoshida^1,3

¹Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Japan.
²Advanced Technology Research Laboratories, Idemitsu Kosan Co., Ltd., Sodegaura, Japan.
³Research Center for Photovoltaic Technologies, AIST, Tsukuba, Japan.

DOI: 10.4236/ampc.2015.52007 PDF HTML XML 2,457 Downloads 2,951 Views

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 proportional relationship between the changes in the conductivities of the two components. The mobilities of the CuPc and C60 layers were calculated from the conductivities and were in the orders of 10^﹣4 and 10^﹣3 cm²/Vs, respectively.

Keywords

Organic Photovoltaic Cells, Impedance Spectroscopy, Modulus Analysis, Photoconductivity

Share and Cite:

Maeda, R. , Tokairin, H. , Takahashi, J. and Yoshida, Y. (2015) In-Situ Measurements of the Photoconductivity of Multi-Layered Organic Photovoltaic Devices Using Impedance Spectroscopy. Advances in Materials Physics and Chemistry, 5, 47-52. doi: 10.4236/ampc.2015.52007.

Conflicts of Interest

The authors declare no conflicts of interest.

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