  Photodiodes are widely used to convert lights into electrical signals. The
conventional silicon (Si) based photodiodes boast high photoelectric conversion
efficiency and detectivity. However, in general, inorganic-based photodiodes
have low visible wavelength sensitivity due to their infrared wavelength
absorption. Recently, electrical conducting polymer-based photodiodes have
received significant attention due to their flexibility, low cost of production
and high sensitivity of visible wavelength ranges. In the present work, we
fabricated an organic photodiode (OPD) consisting of ITO/ NiOx/ P3HT:PC60BM/
YbF3/ Al. In the OPD, a yitterbium fluoride (YbF3) buffer layer was used as the
electron transport layer. The OPD was analyzed for its optical-electrical
measurements, including J-V characteristics, detectivity and dynamic
characteristics. We have investigated the physical effects of the YbF3 buffer
layer on the performance of OPD such as its carrier extraction, leakage current
and ohmic characteristics.
