Impedance Spectroscopy of ITO/ α-NPD/Alq3/LiF/Al Organic Light-Emitting Diodes

The electronic property of organic electroluminescent electro-luminescent electro-luminescent devices having a simple bi-layer structure of α-NPD and Alq
3
was investigated by impedance spectroscopy. We observed hole accumulation in the α-NPD layer and estimated hole mobility was 1.4x10
^-5
cm
²
/Vs.