Temperature coefficient of resistance in ultrathin metal films

Abstract
The temperature coefficient of resistance (TCR) of ultrathin (40–120 Å) metal films is investigated. The effects of temperature, island size, interisland separation, and thickness are incorporated into an analytic expression for the TCR based upon an activated tunneling model. Experimental data are presented to verify the relationships. Anomalous effects, including experimental data, are discussed. An analytic treatment of this situation results in the inclusion of an additional negative term in the TCR expression when compared to the activated tunneling case. The possibilities of positive and negative TCR are indicated.