We report the fabrication of silver plasmon-enhanced photodiodes with a single active layer
sandwich mixture, using ITO with Ag nanoparticles and poly (2-methoxy-5-(20-ethylhexyloxy)-
1,4-phenylenevinylene) (MEH-PPV):fullerene-C60 blend. Ag nanoparticles were created first by ebeam
depositing 20 Å of Ag on ITO followed by RTA annealing under nitrogen at 250 °C for 30
min. Devices were fabricated using spin casting the blend over the ITO/Ag nanoparticles. After
baking, Al metal was deposited on top of MEH-PPV fullerene-C60 blend using e-beam evaporation
for the metal contacts. We observed enhanced absorbance due to the Ag nanoparticles and increased
photo response by the fabricated photodetector. I-V characterization allowed us to determine the
barrier height, diode ideality factor, and series resistance. The diode shows a non-ideal I-V behavior
due to a high probability of electron and whole recombination in the depletion region or existence
of tunneling current, or perhaps due to the presence of interfacial layer or series resistance. The
photocurrent and the photoconductive behavior indicate that these devices can be used as solar cells.
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