The effect of radio-frequency plasma treatment on the electroluminescent properties of violet light-emitting germanium implanted metal-oxide–semiconductor structures

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“…At the beginning of the 1970s, the researches of the lowenergy plasma-ion etching of metals or oxides in the SiO 2 -Si structures showed [37] that ion-beam-assisted plasma etching leads to considerable degradation phenomena: an increase of the leakage current through the dielectric; the building-up of a positive fixed charge near the SiO 2 -Si interface; and the activation of charge transport in the dielectric. However, the following improvement of the equipment and the elaboration of new technological regimes allow one to realize the technologies of plasma treatment leading not only to a simply annealed oxide charge [70] but also to a significant improvement of the SiO 2 -Si properties, for instant: a considerable reduction of the positive fixed charge in the dielectric [2,8,57,68]; a decrease of ion charge transport in dioxide [71]; a better quality of the Sinanocrystals/SiO 2 amorphous matrix interface [10,11], a considerable decrease of the positive charge building-up in oxide after the following irradiation [68], and an increase of the lifetime of metal-oxide-silicon lightemitting diodes (MOSLEDs) operating under high-field electron injection [72,73]. Let us consider consistently these phenomena.…”

“…Critical issues of the MOSLED performance are the device durability in terms of the device operating lifetime which has to be improved and the strong-field injectionassociated oxide degradation which has to be prevented or at least retarded [90,91]. To increase the operation duration of the MOSLEDs, it was suggested to use the RF hydrogen plasma treatment [72,73,92]. It should be noted that mechanisms of violet electroluminescence (EL) is the impact ionization of neutral oxygen-deficient centers (ODC), in one of which the oxygen atoms of the original Si-O-Si bonding configuration are removed allowing the Si atoms to be subsequently replaced by added Ge atoms to form Si-Ge and Ge-Ge bonds [89].…”

“…Variation of the maximal EL intensity with current density measured at a wavelength of 390 nm before and after plasma treatment for electrons injected from Si substrate. Inset: EL specta of Ge-implanted SiO 2 before and after plasma treatment [72].…”

“…EL intensity measured at a wavelength of 390 nm and a constant current voltage as a function of the electron-injected charge before and after plasma treatment for a current density of 2×10 -5 A/cm 2 (plasma power density -0.7 W/cm 2 , additional heating -200 ºC)[72].…”