Influence of polishing of stainless steel substrates on field emission properties of carbon nanotubes films

Carbon nanotubes (CNTs) were synthesized from methane and hydrogen gas mixture directly on stainless steel plates by microwave plasma chemical vapor deposition (MPCVD). By pretreatment of the substrates such as mechanically polishing, we found the polishing can lower the turn-on field and improve the emission current density. The current density of the un-pretreated sample attains 2.9mA/cm/sup 2/, but the polished sample attains 5.5 mA/cm/sup 2/, at the electric field of 7.5 V//spl mu/m.