PHYSICAL PROPERTIES OBTAINED FROM MEASURED THERMAL PROFILES IN THE FILM/SUBSTRATE BIMATERIAL SYSTEM

The microelectronic devices are formed by a substrate that supports the functional thin film material. The thermal, electrical, and mechanical properties of the system depend strongly on the interfacial properties between a film and a substrate. The interfacial nature in a film/substrate system originates the thermal contact resistance (Rtc). We discuss the thermal and the electrical behavior in a film/substrate system (bimaterial system) making emphasis on the Rtc of the interface. Au/glass samples with different thicknesses were prepared by thermal evaporation for experimentation. The bimaterial system was heated by a DC electrical current to obtain thermal profiles. Film and substrate thermal profiles acquired with high resolution combined with a developed bimaterial model are used as an alternative method to estimate the Rtc value at atmospheric pressure, the electrical resistivity ρ, and the thermal resistive coefficient αr in the bimaterial system. The calculated Rtc values ranged from 7.7 × 10-4 to 1.2 × 10-3 m2 K/W for the Au/glass system, in good agreement with previously reported values. The ρ values obtained from the thermal profile data present a more reliable value due to the global character than the local values measured by the four-probe technique. Dependence on film thickness was also found in the αr coefficient determination.