Fabrication and characterization of nanoparticle non-volatile memory

In this study, we fabricated the well-ordered Au nanodot array containing MOS capacitors to investigate the potential to be used in non-volatile memory applications. The thin SiO_2 layer was grown on Boron doped p-type Si wafer by using Rapid Thermal Oxidation method. Electron Beam Lithography (EBL) was performed to control the positions and diameters of nanoparticle array precisely. EBL was performed as single dot exposure by using 30 kV acceleration voltage. SEM images of developed nanodots were taken to examining the exposure and develop quality. The samples were coated with Au at a rate of 3 Å/s Thermal Evaporator and the target thickness was set 13 nm. The ImageJ software used for SEM image analysis and nanoparticle distribution statistics obtained. 30 nm top gate oxide was evaporated by using RF Sputtering. C-V and I-V measurements were carried out to analyze the charge storage properties of the sample. SEM analyses showed that the nanodot density was 10^10 dot per square inch. Operation parameters like program and erase voltage, program speed and retention determined from the electrical characterizations.