A comparative study of the structural and optical properties of Si-doped GaAs under different ion irradiation

Understanding the response and mechanism of semiconductor materials under irradiation environment is important for some critical technological applications. In this work we demonstrate the effects of N+ and Ar+ ion irradiation on structural and optical properties of Si-doped GaAs at room temperature with different doses, when compared with Ar+ ion beam irradiation, Raman spectroscopy reveals a larger lattice strain generated in Si-doped GaAs under 50 keV N+ ion beam irradiation with the 5 x 10(16) cm(-2) dose. However, the irradiation simulations show that the irradiation damage of Ar+ is greater under the 5 x 10(16) cm(-2) dose irradiation. The apparent inconsistency is ascribed to the fact that new <Si-N> bonds and <Ga-N> bonds are generated inside the material after ion irradiation, which causes the vibration mode of the chemical bond of the material to change. Thus, the optical phonon peak in the Raman spectrum shows a large blue shift, and the strain value also increases significantly. Further studies show that when the irradiation dose is greater than 5 x 10(15) cm(-2), the photoluminescence spectrum is quenched, indicating that the luminescent efficiency of GaAs can be significantly reduced whether it is N+ or Ar+ ions. These results indicate that the irradiation damage mechanism of GaAs irradiated by different ions may be completely different, which provides an important reference for studying the irradiation effects of other ions on GaAs.