A fluid ejection module includes a flow-path body, a first oxide layer, a membrane, and a second oxide layer. The flow-path body has a first outer surface and an opposing second outer surface and a plurality of flow paths, each flow path extending at least from the first outer surface to the second outer surface. The first oxide layer coats at least an interior surface of each of the flow paths and the first and second outer surfaces of the flow-path body and has a thickness that varies by less than 5% along {100} planes. The membrane has a first outer surface. The second oxide layer is coated on the first outer surface of the membrane and has a thickness that varies by less than 5% along {100} planes and is bonded to the first oxide layer.