NOVELTY - The layer has several membrane electrodes assemblies (MEAs) (120) and each MEAs includes an electrolyte membrane (122), an anode catalyst layer (124) provided on one face of the electrolyte membrane and a cathode catalyst layer (126) provided on other face of electrolyte membrane. An inter-connector (130) electrically connects anode catalyst layer of one of adjacent MEAs to cathode catalyst layer of other of adjacent MEAs. The inter-connector is formed of a material that constitutes anode catalyst layer and cathode catalyst layer.    USE - Fuel cell layer for fuel cell system (claimed). Uses included but are not limited to space application, automobile, mobile device such as cell phone, notebook size personal computer, personal digital assistant (PDA), MPEG audio layer-3 (MP3) device, digital camera, electronic dictionary, electronic book and large and small scale power generation applications.    ADVANTAGE - The number of the materials required for planar fuel cells can be reduced, so that the fabrication of the fuel cell layer can be simplified. The cross leak occurring through the inter-connector can be prevented by employing the fabrication process and the formation of the seal layers. Each inter-connector can be structured by joining together the protrusion formed integrally with the anode and the cathode catalyst layers, so the contact resistance between the inter-connector and the each catalyst layer can be reduced. The amount of the catalyst materials required for the formation of the inter-connector can be suppressed and the manufacturing cost of the system is reduced. The catalyst layers are not press-bonded to the electrolyte membrane by the press machine, so the risk of causing damage to the electrolyte membrane can be reduced.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) fuel cell system; and    (2) method for fabricating fuel cell layer.    DESCRIPTION OF DRAWING(S) - The drawings show a cross-sectional view of the fuel cell layer and the inter-connector.    Membrane electrodes assemblies (120)    Electrolyte membrane (122)    Anode catalyst layer (124)    Cathode catalyst layer (126)    Inter-connector (130)