Room- and low-temperature voltage tunable electroluminescence from a single layer of silicon quantum dots in between two thin SiO2 layers

Room- and low-temperature electroluminescence (EL) in the visible range was observed from a single layer of silicon nanocrystals in between two thin S iO2 layers. The EL peak wavelength exhibited tunability from the red (simil ar to 800 nm) to the yellow (similar to 600 nm) depending on the excitation voltage. By decreasing the temperature while keeping the excitation voltag e constant, an increase in EL intensity was observed together with a bluesh ift in EL peak position. This blueshift was much larger than that observed under optical excitation. Nonradiative Auger recombination, Coulomb chargin g effects, and/or the quantum-confined Stark effect are considered accounta ble for this behavior. (C) 2000 American Institute of Physics. [S0003-6951( 00)02336-6].