A fluid ejector includes a substrate having an exterior surface and an interior surface. A non-wetting coating can cover at least a portion of the exterior surface and can be substantially absent from the flow path. A non-wetting coating can be formed of a molecular aggregation. A precursor of a non-wetting coating may flow into a chamber at a higher temperature higher than the substrate. A non-wetting coating can be over a seed layer. An outer portion of the seed layer can have a higher concentration of water molecules or a greater density than an inner portion. The outer portion can be deposited at a ratio of partial pressure water to partial pressure matrix precursor that is higher than the ratio for the inner portion. An oxygen plasma can be applied to a seed layer on the exterior surface, and the non-wetting coating can be applied on the seed layer.