Full MEMS monolithic microcolumn for wafer-level arrayal

Recently, an advanced microcolumn concept for improved throughput was proposed. However, due to the complexity of the approach, the miniaturization was limited. In addition, microcolumns must run under ultrahigh vacuum conditions in order to obtain stable electron emission at the field-emission tip. Both signal and power lines need to be connected through the ultrahigh vacuum chamber. Therefore, increases in the number of microcolumn arrays necessitate more wiring from the external control unit to the internal units, and the number of wires can become prohibitive. To solve this problem, a new concept, exploiting the possibility of an arrayed microcolumn which uses microelectromechanical systems (MEMS) technology has been developed. This paper describes a monolithic (3×3 arrayed) microcolumn, which consists of a cold field-emission tip, an input lens, an einzel lens, and novel deflectors for multiple-arrayed microcolumns. We also describe its fabrication process, which relies on improved microfabrication a...