Thermal conductivity of SiO2 films by scanning thermal microscopy

In microelectronics the thermal conductivity of dielectric films such as SiO2 is of concern because, as dimensions shrink, heat removal from devices becomes a critical problem. A scanning thermal microscope was used to image thermal properties of silicon dioxide films deposited on silicon by plasma enhanced chemical vapor deposition. Thermal conductivity as a function of the layer thickness, ranging 50-1000 nm was measured. To interpret the experimental thermal data, a model has been developed on the basis of previously published heat-transfer concepts. An intrinsic thermal conductivity of 1.31 +/- 0.11 W/K/m was calculated independent of the thickness and a thermal resistance of (6.8 +/- 0.35) x 10(-7) m(2) K/W was calculated at the interfaces.