PREDICTION AND MEASUREMENT OF THE THERMAL-CONDUCTIVITY OF AMORPHOUS DIELECTRIC LAYERS

Thermal conduction in amorphous dielectric layers affects the performa nce and reliability of electronic circuits. This work analyzes the inf luence of boundary scattering on the effective thermal conductivity fo r conduction normal to amorphous silicon dioxide layers, k(n,eff). At 10 K, the predictions agree well with previously reported data for dep osited layers, which show a strong reduction of k(n,eff) compared to t he bulk conductivity, k(bulk). A steady-state technique measures k(n,e ff) near room temperature of silicon dioxide layers fabricated using o xygen-ion implantation (SIMOX). The predictions and the SIMOX data, wh ich agree closely with k(bulk), show that boundary scattering is not i mportant at room temperature. Lower than bulk conductivities of silico n dioxide layers measured elsewhere near room temperature must be caus ed by interfacial layers or differences in microstructure or stoichiom etry.