The growth of the Pd2Si thin fllms on Si(111) substrates has been monitored by an in situ x-ray diffraction technique in vacuum and in helium atmosphere from 160 to 250 °C. A familiar parabolic growth rate was found, confirming the diffusion-controlled film growth process. The activation energies were found to be 1.34 and 1.37 eV for the measurements performed in vacuum and helium environment, respectively. Stress relaxation in the growing Pd 2Si fllm was observed when the reaction temperature exceeds 200 °C. The relaxed films showed a higher degree of texture as evidenced by the rocking curve measurements.