Ions beam-induced luminescence(IBIL) analysis is a real-time in-situ spectroscopy technique. Due to its sensitivity to the internal structure of the sample, it brings us certain difficulties in analyzing the spectral peaks information of the sample. In order to more accurately split the peaks of the IBIL energy spectra to more clearly determine the luminescence centers of different defects of the material, this paper proposes a Voigt function based on the LM (Levenberg-Marquardt ) of non-linear least squares algorithm to split the deep band emission peaks in the IBIL energy spectra of ZnO at 100 and 200 K. By comparing the fluctuation of the position of the peak with fluence after the Gauss function and the Voigt function are fitted to the energy spectrum, it is found that the position of the peak obtained by the Voigt function fitting is stable and the convergence speed is fast. At the same time, by comparing the full width at half maximum (FWHM) of the Gaussian function with the FWHM of the Lorentz function of the three sub-peaks of 1.75 , 1.95 and 2.10 eV after fitting using the Voigt function, it is found that the FWHM of the Lorentz function is about 1/10 of FWHM of the Gaussian function. Moreover, the 1.95 eV peak at 100 K, 1.75 and 1.95 eV peak at 200 K, the FWHM of the Lorentz peak is below the order of magnitude, indicating that the non-uniform broadening ( Gaussian broadening) is still the main mechanism of spectral peak broadening; while the scattering of electrons and phonons is the main mechanism of Lorentz broadening. For the 2.10 eV sub-peak involving a large number of electrons in the conduction band, the FWHM of the Lorentz function at 200 K is significantly greater than 100 K, and the thermal vibration of the crystal lattice is intensified at a higher temperature, and the thermal movement of electrons is strengthened. It increases the probability of scattering, strengthening the scattering effect of electrons and phonons, further broadening the Lorentz spectrum. The red light with the peak center at 1.75 eV is mainly related to V_Zn. At 100 K, the FWHM of this is 0.02 eV, but it becomes extremely small at 200 K. This is because bound electrons or excitons get enough thermal kinetic energy at 200 K to get rid of the V_Zn bond, weaken the scattering effect with the surrounding lattice, so that the Lorentz broadening becomes extremely weak. The experimental results show that the Voigt function is more suitable for IBIL energy spectrum fitting to split peaks, which also provides an example for the future application of IBIL to the energy spectrum analysis of the internal structure of other materials.