A possible interaction between nonalkali metals and C60 thin films

By measuring the resistance in situ during the deposition of metals-C 60 multilayer thin films on sapphire substrates at room temperature, the authors find that the resistance decreases sharply when adding C 60 on some metal layers. There are two possible explanations: one is the formation of a conduction layer of metal- (Sn-, Ba-, Ga-) doped C 60; the other is a bonding interfacial interaction between the metal and C60 layers, which may result in a better continuous metal layer.