Electroluminescence from thin SiO2 layers after Si- and C-coimplantation

In this paper we explore the electroluminescence (EL) properties of thermally grown 350 nm thick SiO₂ layers co-implanted with Si⁺ and C⁺ ions. The implanted fluences were chosen in such a way that peak concentrations of excess Si and C of 5–10 at% were achieved. The devices show a broad photoluminescence (PL) between 2.0 and 3.2 eV with a main peak around 2.7 eV. The broad EL spectra show additional peaks around 3.3 eV and between 2.1 and 2.5 eV which are decreased with increasing Si/C concentration. The shape of the EL spectra does not change with increasing injection currents which implies that various types of defects occur for the different concentrations. The device stability is improved in comparison to Ge or Sn implanted oxide layers.