Organic devices have many advantages such as low material consumption and low energy requirements, but they have serious issues regarding long term stability. Hence we need to develop a barrier film which solves this problem. Initially, the organic devices were fabricated on glass and were encapsulated using glass and epoxy (as sealant). Gradually there was a need to shift on to flexible substrates which required encapsulation to be flexible as well. Therefore, the motivation of the work is to develop thin film encapsulation that can be made flexible. The low temperature PECVD grown films of SiOx and SiNxwere used as the barrier film. Alternate inorganic layers (2-dyads) provided barrier of ~10-2 g/m2 day and increasing the number of dyads to five improved the water vapor transmission rate (WVTR) only by one order of magnitude. However, introducing organic layers in this structure resulted in WVTR value of order 10-5 g/m2 day. The organic layers were deposited by spray technique.
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