ANNEALING-TEMPERATURE DEPENDENCE OF THE THERMAL-CONDUCTIVITY OF LPCVD SILICON-DIOXIDE LAYERS

The reliability and performance of electronic circuits are influenced by heat conduction in low-pressure chemical-vapor-deposited (LPCVD) silicon dioxide layers. This work measures the effective thermal conductivity k(eff) for conduction normal to films of LPCVD silicon dioxide layers as a function of annealing temperature, as well as for films of thermal and SIMOX oxides. The LPCVD oxide thermal conductivity increases by 23% due to annealing at 1150-degrees-C. The conductivities k(eff) of LPCVD layers of thicknesses between 0.03 and 0.7 mum are higher than those reported previously for CVD layers, and vary between 50% and 90% of the conductivities of bulk fused silicon dioxide. The values for SIMOX and thermal oxide layers are within the experimental error of the values for bulk fused silicon dioxide.