Plasma-enhanced quantum-well intermixing (QWI) has been developed for tuning the bandgap of InGaAs-InP material using an inductively coupled plasma system. The application of inductively coupled plasma enhances the interdiffusion of point defects resulting in a higher degree of intermixing. Based on a semi-empirical model of QW interdiffusion, the bandgap blue-shift with respect to the plasma exposure time and inductively coupled plasma energy has been analyzed. The theoretical results appear to be in good agreement with the experimental data of the intermixed samples. The model serves as a good simulation tool to explain the intermixing mechanism and further to optimize the intermixing process for the fabrication of the photonic integrated circuits.