Dependence of the stored charges and tunneling voltages on the tunneling SiO2 thickness for Si nanoparticles embedded in a SiO2 layer

Dependence of the stored charges and the tunneling voltages on the tunneling SiO2 thickness for Si nanoparticles embedded in a SiO2 layer formed by the sonochemical method was investigated by using electrostatic force microscopy (EFM) measurements. Bright-field transmission electron microscopy images showed that Si nanoparticles were embedded in a SiO2 layer. EFM images for the Si nanoparticles embedded in a SiO2 layer under applied bias voltages showed that the localized charges remained in the Si nanoparticles embedded in a SiO2 layer. The stored charge in the Si nanoparticles embedded in a SiO2 layer increased with a decrease in the tunneling SiO2 thickness. While the threshold tunneling voltage increased with an increase in the tunneling oxide thickness, the mean amplitude of the tunneling voltage increased with a decrease in the thickness of the tunneling SiO2 layer.