Defect-Enhanced Visible Electroluminescence of Multi-Energy Silicon-Implanted Silicon Dioxide Film

摘要

White-light and blue-green electroluminescence (EL) of a multirecipe Si-ion-implanted SiO_(2) (SiO_(2):Si~(+)) film on Si substrate are demonstrated. The blue-green photoluminescence (PL) is enhanced by the reaction of O_(3)≡Si-O-Si≡O_(3)→O_(3)≡Si-Si≡O_(3)+O_(interstitial) during Si implantation. After annealing at 1100℃ for 180 min, the luminescence at both 415 and 455 nm is markedly enhanced by the complete activation of radiative defects, such as weak oxygen bonds, neutral oxygen vacancies (NOVs), and the precursors of nanocrystallite Si (E_(δ)~(′) centers). Absorption spectroscopy and electron paramagnetic resonance confirm the existence of NOVs and E_(δ)~(′) centers. The slowly rising E_(δ)~(′)-related PL intensity reveals that the formation of nanocrystallite Si (nc-Si) requires longer annealing times and suggests that the activation energy for diffusion of excess Si atoms is higher than that of other defects in ion implanted SiO_(2). The EL from the Ag-SiO_(2):Si~(+)-Si-Ag metal-oxide-semiconductor diode changes from deep blue to green as the driving current increase from 0.28 to 3 A. The maximum white-light luminescent power is up to 120 nW at a bias current of 1.25 A.