Preparation of Tungsten Tip that Emits Electron at Extremely Low Bias Voltage

A new modification technique of tungsten tip was invented, which results a tip apex capable of emitting at extremely low bias voltages. Freshly prepared tips were characterized by field ion microscopy (FIM) and field emission microscopy (FEM) to resolve the atomic structure of the apex and to monitor the field emission pattern. Thus, it is presumed that the FIM-induced modified O/W tip apex has local negative electron affinity or extremely small work function resulting a nearly zero potential barrier for electrons to emit. These electrons are lead to a narrow pathway at the center of the extractor resulting a narrowest opening angle towards the MCP