@ARTICLE{Behjat, author = {Ghoshani, Maral and Behjat, Abbas and Jafari, Fatemeh and torabi, Naimeh and }, title = {Thin-film Encapsulation of Organic Light-Emitting Diodes Using Single and Multilayer Structures of MgF2, YF3 and ZnS}, volume = {7}, number = {1}, abstract ={In this research, the lifetime of green organic light emitting diodes (OLEDs) is studied using four passivation layers. To encapsulate the OLEDs, MgF2, YF3, composed of alternating MgF2/ZnS and YF3/ZnS layers were grown by thermal vacuum deposition. Measurements show that the device lifetime is significantly improved by using YF3 and ZnS as passivation layers. However, diodes encapsulated by MgF2/ZnS and YF3/ZnS nano-structures show a highly efficient gas diffusion barrier that results in a longer lifetime of the devices. The half lifetime of the green OLEDs reached 1200 minutes using YF3/ZnS layers. The electroluminescence (EL) and current-voltage characteristics of the devices were also examined to compare the electrical and the emissivity properties of the devices before and after encapsulation. This simple and inexpensive thin-film encapsulation method would be potentially employed to capsulate top emitting OLEDs and flexible OLEDs due to their good performance and easy fabrication. }, URL = {http://ijop.ir/article-1-124-en.html}, eprint = {http://ijop.ir/article-1-124-en.pdf}, journal = {International Journal of Optics and Photonics}, doi = {}, year = {2013} }