Laser interference based direct writing is a potential solution for wide range of fabrication of nanostructure. This paper deals with two dimensional heat conduction analysis and the simulation of the same on silicon and germanium surfaces. Simulation of direct writing of patterns with 193nm, 27nsec, single pulse laser source with power varied from 800mJ/cm 2 to 1100mJ/cm 2 are presented. The rise in the temperature on the surfaces as well as beneath the surface is analyzed on the basis of the results. We also report about the dependency of the thermal diffusion length on the homogeneity of the formed structures.