Electro-thermal resistance of GaAs interconnects

This paper describes the effect of steady-state heating on the electrical and thermal resistance of interconnects on GaAs. Examined is a typical dual-layer metal interconnect system, common to GaAs processing. The interconnect system is considered in three parts, the interconnect metals, the Si3N4 dielectric surrounding the metal, and the Al xGa1-xAs epitaxial substrate. Using a meandering line as a test structure, measurements show how the direct current (DC) resistance increases with both temperature and dissipated power. Thermal resistors are proposed to account for self-heating and thermal coupling.