Determination of the temperature coefficient of resistance from micro four-point probe measurements

Current characterization methods of the temperature coefficient of resistance (TCR) of thin films are often limited to slow macroscale measurements, which further require a direct determination of temperature. In this work, we present an innovative application of micro four-point probe (M4PP) sensing, which enables a fast, non-destructive, local measurement of Joule heating effects that can be translated into TCR of the thin film. Analytical expressions for the four-point resistance response to local heating, and ultimately the temperature profile during an M4PP measurement, are derived and validated against finite element models. The method is successfully demonstrated on three metal thin films (7, 10, and 16 nm platinum deposited on fused silica). We evaluate TCR using two different electrode configurations, resulting in unique temperature fields, and observe a measurement repeatability of