Stability of 8-hydroxyquinoIine aluminum films encapsulated by a single Al_2O_3 barrier deposited by low temperature atomic layer deposition

摘要

100 nm thick 8-AlQ_3 films deposited onto silicon wafers have been encapsulated by mean of low temperature atomic layer deposition of Al_2O_3 (20 nm). Investigation of the film evolution under storage test as harsh as 65 ℃/85% RH has been investigated up to -1000 h and no severe degradation could be noticed. The results have been compared to raw AlQ_3 films which deteriorate far faster in the same conditions. For that purpose, fluorescence measurements and atomic force microscopy have been used to monitor the film evolution while transmission electron microscopy has been used to image the interface between AlQ_3 and Al_2O_3. This concept of bilayer AlQ_3/Al_2O_3 barrier films has finally been tested as an encapsulation barrier onto an organic light-emitting diode.