In this work, a generalized model on plasma, thermal and elastic waves was used to study the wave propagation of semiconducting material during the photo-thermal process. The thermal relaxation time, the coupling between the plasma, thermal, and elastic waves has been considered. The analytical solutions in the transformed domain by the eigenvalue approach have been obtained based on the techniques of Laplace's transform. A semiconducting material like as silicon was considered. The results were graphically represented to show the effect of the thermal relaxation time, the thermal activation coupling parameter, the lifetime on the physical quantities.