This project models free carrier generation and thermal heating in the Si wafer illuminated by constant wave focused laser beam. Non-linear dependence of the carrier diffusion on the carrier concentration is taken into account by using a room temperature experimental data recently measured. Non-linear temperature dependence of the thermal conductivity of Si is taken into account by using the experimental data for intrinsic Si, as well as laser penetration depth dependence on laser wavelength . Nonlinear (Auger and radiative) carrier recombination is included in the model. Surface carrier recombination is also considered. The calculation is performed in Matlab program, using functions of PDE toolbox for solution, and the interactive PDE tool (file pdetool.m) for the generation of geometry description matrix and boundary condition matrix. Archive file with all files of the project can be obtained by ftp from the Computational Physics ftp server. More information here and by email to firstname.lastname@example.org .