DETERMINATION OF THE THERMAL-CONDUCTIVITY OF CMOS IC POLYSILICON

The thermal conductivities of two polycrystalline silicon layers as pr oduced by a commercial CMOS IC process are reported for the temperatur e range of 100 to 430 K. One layer, n-doped with a sheet resistance of 25 OMEGA/sq., has a thermal conductivity kappa(n) of 29 W/mK at 300 K . The second layer, p-doped with a sheet resistance of 225 OMEGA/sq., has a thermal conductivity kappa(p) of 18 W/mK at 300 K. These values were obtained with micromechanical test structures fabricated with a c ommercial CMOS IC process, and post-processed by anisotropic etching. The one-dimensional model used to calculate the thermal conductivities from the raw experimental data was validated by the simulation of the three-dimensional temperature field in the test structures with the f inite element simulation program SESES.