Abstract：We report fabrication and characterization of organic heterojunction UV detectors based on N,N'?bis(naphthalen?1-yl)-N,N'-bis (phenyl) benzidine (NPB) and fullerene C60. The effects of different thicknesses of NPB and C60 layers are studied and compared. Notably, the optimal thicknesses of electron acceptor C60 and electron donor NPB are 40 nm and 80 nm, respectively. The J–V characteristic curves of the device demonstrate a three-order-of-magnitude difference when illuminated under a 350 nm UV light and in the dark at -0.5 V. The device exhibits high sensitivity in the region of 320–380 nm with the peak located around 350 nm. Especially, it shows excellent photo-response characteristic with a responsivity as high as 315 mA/W under the illumination of 192 μW?cm?2 350 nm UV light at -5 V. These results indicate that the NPB/C60 heterojunction structure device might be used as low-cost low-voltage UV photodetectors.
2015, Vol. 32 
