The characteristics of a heterojunction diode consisting of C60/tetrat
iafulvalene(TTF) which are typical of a photoinduced rectifier, are re
ported. The device under dark conditions is almost insulative, however
, upon light illumination, marked rectification is observed. The forwa
rd bias to C60 under illumination is positive against the TTF electrod
e. The results are discussed in terms of the photoinduced electron tra
nsfer from TTF to C60 at the junction.