Temperature-dependent thermal conductivities of CMOS layers by micromachined thermal van der Pauw test structures

Temperature-dependent thermal conductivities of five different layer sandwiches and two thin films of an ASIC CMOS process are reported. Measurements were based on the thermal equivalent of the van der Pauw (VDP) method to extract the sheet resistance of thin films. Thermal sheet resistance data were acquired using micromachined thermal test structures between 100 and 420 K. From these results, the thermal conductivities of, e.g., the silicon nitride passivation layer, the thermal oxide, and of a PECVD silicon oxide bilayer of the CMOS process were deduced. Values of k = 1.28 +/- 0.01, 1.5 +/- 0.1 and 0.93 +/- 0.04 W m(-1) K-1 were found, respectively, at 300 K,with respective temperature coefficients of thermal conductivity TCk = 1.29 x 10(-3). 1.0 x 10(-3) and 1.5 x 10(-3) K-1. The influence of ilon-ideai temperature control during the measurement on the K accuracy was investigated and is shown to be negligible. (C) 2002 Elsevier Science B.V. All rights reserved.