Bondable fluorinated barrier coatings on oxidized metal surfaces. The barrier coatings include a perfluorinated silane having a C2-C30 alkyl chain with a reactive silicon end containing 1 to 3 leaving groups. The perfluorinated silane layer is covalently bonded to an underlying oxide layer and the outer surface is treated with an atmospheric-pressure plasma treatment. The resultant barrier coating exhibits corrosion resistance attributed to perfluorinated silanes but with enhanced bonding/adhesion properties.