The phenomenon of heat conduction is important in semiconductor devices. This property is investigated on the basis of modified Callway model. The formalism was carried out using Hamiltonian, phonon Green’s function and equation of motion techniques for various scattering events. It was found that every scattering mechanism is independent of each other and does not affect the others. The thermal conductivity of lead sulphide (PbS) semiconductor has been studied on the basis of this concept. The results of the present model are in good agreement with experimental results and the model shows good future scope with other semiconductors and superconductors.