Electron Field Emission Properties of Co Quantum Dots in SiO2 Matrix Synthesised by Ion Implantation

Crystallised Co nanoparticles were synthesized by Co
⁺
implantation onto thermally oxidised SiO
₂
layers on silicon substrate. The implantation energy was 50 keV and the doses ranged from 1 to 7times10
¹⁶
Co
⁺
/cm
²
. The possibility of controlling the size and distribution of the nanoclusters by changing implantation conditions (e.g. dose and energy) is the main advantage of this technique. Atomic force microscopy (AFM) and cross-sectional transmission electron microscopy (X-TEM) were used to characterize the nanoclusters. The staircase I-V curve also shows that the metallic quantum dots embedded in a thin SiO
₂
layer on silicon substrate has effective Coulomb blockade at room temperature