In situ electrical transport during isothermal annealing of nanocrystalline gold films

Advanced gas deposition was used to produce nanocrystalline gold films under conditions giving four different deposition rates. Grain growth and structural modification of the grain boundaries were probed during annealing by use of in situ electrical transport measurements. Time dependent resistivity data were fitted to a relaxation model whose activation energy went up upon increased isothermal annealing temperature. The grain boundary transmission coefficient for the samples scaled, up to a certain limit, with the deposition rate; this is believed to be due to a higher concentration of pores, or a wider grain boundary region containing a disordered structure, in samples prepared at low deposition rates. Such samples also displayed enhanced thermal stability with negligible grain growth up to 773 K upon annealing in vacuum for 2 h. Samples prepared above this limit, at the highest deposition rate, exhibited a decreased grain boundary transmission coefficient. (C) 2002 American Institute of Physics.