DIFFUSION BARRIER COATINGS HAVING GRADED COMPOSITIONS AND DEVICES INCOROPRATING THE SAME

摘要

An organic light-emitting device (310) incorporates a composite article to provide an extended life thereto. The composite article comprises a substrate (340) having at least a substrate surface and a graded-composition coating (350) disposed on a substrate surface. The composition of the coating material varies substantially continuously across its thickness. The coating (350) reduces the transmission rates of oxygen, water vapor, and other chemical species through the substrate (340) such that the composite article can be used effectively as a diffusion barrier to protect chemically sensitive devices (320) or materials.