Applied Physics Letters · 1998 · 14 citations · 10 references
EngineeringMaterials EngineeringMaterials ScienceElectronic MaterialsSemiconductor DevicesSemiconductor MaterialsLight-emitting DiodesOptoelectronic DevicesOptoelectronic MaterialsSemiconductor Device MaterialsSemiconductor SurfacesSilicon MaterialsElectroluminescenceInfrared Light-emitting DiodesInternal Quantum EfficiencyLight-emitting DevicesPhotoluminescencePorous SiliconReverse Bias CharacteristicsSilicon Nanostructures
Schottky barrier porous silicon diodes have been fabricated showing electroluminescence peaking at 500 nm, with an internal efficiency for blue–green emission of about 0.1%. The structures, on low-resistivity n-type silicon, operate in reverse bias. Scanning tip light emission measurements show a peak emission at 630 nm, closer to that of photoluminescence from the identical surface at 700 nm than that of the electroluminescence. The latter is concluded to arise from nonquantum effects, at the metal interface. The threshold for visible light emission is at 0.2 mA/cm2, and for infrared light is an order of 10 higher. The lifetime in air is short when unencapsulated, but longer in vacuum.
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