Morphology control and electron field emission properties of high-ordered Si nanoarrays fabricated by modified nanosphere lithography

High-ordered silicon nanoarrays were prepared using direct nanosphere lithography combined with thermal oxidation. Atomic force microscope (AFM) images of the silicon arrays show that the patterns of polystyrene (PS) template are well transferred to the silicon surface. The size and morphology of the nanoarrays can be controlled effectively by varying the plasma-therm reactive ion etching (RIE) or thermal oxidation parameters. The field emission studies revealed that the typical turn-on field was about 7-8 V/μm with emission current reached 1 μA/cm2. It is also found that the field emission current is highly dependent on the morphology of these Si nanoarrays.