Semiconductor materials play a crucial role in the fields of science, engineering, and technology due to their high importance. In this work, photoelastic (PE) deformations due to the photonically excited processes are studied according to the photogenerated carriers (plasma waves) during the recombination processes. A photoacoustic theoretical model for the optically excited Silicon (Si) polymer material under the effect of magnetic field is introduced. The coupled between the acoustic and plasm-thermomechanical waves is considered. The governing equation according to the photo-thermoelasticity theory with acoustic pressure is derived. The optoelectronic and thermoelastic properties of semiconductor material are taken into account. The analytical expression of the main physical fields (temperature, mechanical stress, displacement, carrier density, and acoustic pressure) is obtained mathematically using the harmonic wave technique. The theoretical results are represented graphically due to the strength of the magnetic field in two and three dimensions (2D and 3D) and some comparisons are investigated