Photo-excited carrier transport of CuPc/C 60 organic thin-film solar cells

We prepare copper phthalocyanine (CuPc)/C 60 -based organic thin-film solar cells and investigate photo-excited carrier lifetime to reveal the carrier transport dynamics of the solar cells. The photo-excited carrier was generated by irradiation of pulsed laser light of Nd-YAG laser. The obtained carrier lifetime is much longer than that of estimated lifetime from the mobility of thin-film layers. This means the carrier transport cannot be described by a general carrier drift model. In addition, the carrier lifetime become short under white halogen light illumination. The results suggest that the trapping levels exist in organic layers..