Synchronized swinging of electroluminescence intensity and peak wavelength with Si layer thickness in Au/SiO2/nanometer Si/SiO2/p-Si structures

SiO2/nanometer amorphous Si/SiO2 structures with Si layers of twelve different thicknesses in a range of 0-3.0 nm have been deposited with the two-target alternative magnetron sputtering technique. Electroluminescence (EL) from the Au/SiO2/nanometer amorphous Si/SiO2/p-Si structures has been observed. It is found that the EL peak intensity and peak wavelength synchronously swing with increasing Si layer thickness. The experimental results strongly indicate that the EL originates from luminescence centers in SiO2 layers rather than from the Si layers in the structures. The tunneling of electrons and holes and the quantum confinement effect for them in the nanometer Si layers play important roles in the EL. (C) 1999 American Institute of Physics. [S0003-6951(99)04315-6].