Abstract <p>In the present study, we examine the fundamental solution and Green’s function in a semi-infinite orthotropic micropolar photothermoelastic medium based on Moore-Gibson-Thompson heat equation (MPMGT). To achieve this, we first translate the governing equations into two dimensions and execute the dimensionless quantities, and then we employ operator theory to derive the general solution for the MPMGT model. The fundamental solution and Green’s function for a steady point heat source on the surface and in the interior of a semi-infinite medium of the assumed model have been computed from the general solution using newly introduced harmonic functions. To investigate the micropolarity effect, displacement, stress, temperature, carrier density distribution, micro rotation and couple stress are computed numerically and presented as graphs. Specific cases are inferred from the current investigation and compared with the previously established results. The obtained results have applications in the material and engineering sciences, as well as in the different semiconductor elements during the coupled photothermoelastic impact.</p>