Abstract
The temperature dependency of resistance of vacuum deposited gold and platinum films between room temperature and 400° and 600° C, respectively, has been studied. Particular emphasis has been placed on the transition between thick, continuous films with positive temperature coefficients and thin, granular, or lacunary films with negative temperature coefficients. In addition to the low positive coefficients usually observed in this transition region, a minimum in the resistance vs temperature curve is observed. It is shown that the observed behavior can be attributed to a linear combination of the resistance of the individual grains or aggregates and the resistance due to gaps or potential barriers between the grains. The behavior in the transition region depends critically on the size of both the barriers and grains in the film.