Temperature profiles were calculated numerically for a three-layer stack of SiO2-Si-SiO2 on top of a monocrystalline Si substrate. The stack was locally heated by a CO2 laser whereas the wafer background temperature was controlled by a heat chuck. The calculation method makes it possible to simulate temperatures as functions of laser power, spot radius, scan speed, substrate bias temperature, and layer thickness. These parameters play a major role in CO2 laser recrystallization of polycrystalline silicon for making single crystalline silicon films on insulator films. It is shown that under conditions of maximum absorption experimental verification of the calculations is possible by measuring the recrystallized track width. A good agreement was found between the calculated and measured results.