The present invention provides an
organic light emitting device and a fabrication method thereof, comprising a substrate, an
anode layer formed on said substrate, an organic function layer formed on said
anode layer, and a
cathode layer formed on said organic function layer, characterized in that, further comprising a
cathode interface modification layer between said organic function layer and said
cathode layer, wherein said cathode interface modification layer contains a compound AxByCz, A is an element of Group IA or IIA, B is an element of Group IIIA or VA, C is a
hydrogen element, and 1≦x≦2, y ∈ [0,1], 1≦z≦4. In the present invention, the cathode interface modification layer is formed after forming a light emitting layer, the cathode interface modification layer contains a compound AxByCz, the
electron injection ability at the cathode interface can be improved by adding the cathode interface modification layer, and hence the device performance can be significantly improved. At the same time, the process feasibility of the material is good during the fabrication, and thus the yield of the device can be further improved.