A novel technique for in-plane thermal conductivity measurements of electrically conductive interconnects and nanostructures

Accurate modeling of heat transport in multi-level interconnects of advanced microprocessors requires accurate knowledge of the thermal properties in thin film structures. The commonly used suspended bridge structures for the lateral thermal conductivity measurements of the metallic thin films involves significant microfabrication process and often cannot produce suspended structures with dimensions near 100 nm×100 nm. In this paper, a novel technique for the in-plane thermal conductivity measurements of electrically conductive structures is presented. Thin interconnects or nanostructures can be deposited on a silicon dioxide layer of thickness near ∼1 μm and then patterned to form a bridge with the width comparable to or less than 100 nm. Joule-heating in the patterned bridge results in a temperature distribution that is strongly dependent on the lateral conduction along the bridge itself through the silicon dioxide layer. The feasibility of the proposed structure for thermal conductivity measurement is investigated by performing careful sensitivity analysis.