NOVELTY - The method comprises applying a solvent including a fluorocarbon such as polytetrylflorylethlene (PTFE) particles to a diffusion media substrate and a carbon fiber substrate, and heating the substrate using microwave radiation to dry the solvent so that the fluorocarbon is dispersed on the substrate. The heating step includes varying the frequency of the microwave radiation in the range of 500 MHz to 1000 GHz. The step of applying the solvent includes dipping the substrate in an aqueous solution. The dried diffusion media substrate has a carbon to fluorine (C/F) ratio of 8-20.    USE - The method is useful for fabricating gas diffusion media for a fuel cell such as proton exchange membrane fuel cell, which is useful as a source of power for vehicles.    ADVANTAGE - The method is capable of effectively fabricating the gas diffusion media with increased hydrophobicity for the fuel cell that exhibits improved performance and a relative constant voltage over a wide range of reactant gas flow rates.    DETAILED DESCRIPTION - The method comprises applying a solvent including a fluorocarbon such as polytetrylflorylethlene (PTFE) particles to a diffusion media substrate and a carbon fiber substrate, and heating the substrate using microwave radiation to dry the solvent so that the fluorocarbon is dispersed on the substrate. The heating step includes varying the frequency of the microwave radiation in the range of 500 MHz to 1000 GHz. The step of applying the solvent includes dipping the substrate in an aqueous solution. The dried diffusion media substrate has a carbon to fluorine (C/F) ratio of 8-20. Fuel cell (10) is part of a fuel cell stack on a vehicle. An INDEPENDENT CLAIM is included for a system for fabricating diffusion media for a fuel cell.    DESCRIPTION OF DRAWING(S) - The diagram shows a cross-sectional view of a fuel cell in a fuel cell stack.    Fuel cell (10)    Cathode side (12)    Anode side (14)    Electrolyte membrane (16)    Cathode side diffusion media layer (20)    Cathode side catalyst layer. (22)