LIQUID METAL ION SOURCE, METHOD FOR MANUFACTURING LIQUID METAL ION SOURCE, AND ION BEAM EMISSION INSTRUMENT

摘要

A liquid metal ion source 10 consists of a needle electrode 11 which is made from two metal wires 11a and 11b arranged in parallel with their outer surfaces being in contact with each other. The needle electrode 11 has a guide passage 11c and an emission end T, both of which are also formed by two metal wires 11a and 11b. The guide passage 11c continuously extends to the emission end T. Towards the bottom of the guide passage 11c, the width of the guide passage 11c decreases to zero. When liquid metal is supplied to the guide passage 11c, capillary action is created in the region close to the bottom of the guide passage 11c, and "volume flow" instead of the usual "surface flow" of the liquid metal occurs. The principle and phenomenon of "volume flow" corresponds with that of a fountain pen. The guide passage 11c continuously extends to the emission end T. Thus, the flow of the liquid metal towards the emission end T is stably continued, and the emission current of the ion beam is stabilized even in case of liquid metal with low wettability. Furthermore, the emission end T is formed to be the hypothetical single emission end. Thus, the controllability of the point and direction of the ion beam is maintained.