An ion is an atom or a molecule such as helium or oxygen that is positively or negatively charged. An ion beam is a flow of ions moving in the same direction at a constant speed. One of the characteristics of an ion beam is the ease and freedom with which its flow rate, direction and speed can be controlled. This characteristic has made ion beam technology central to the science of electronic materials, especially in the semiconductor field. The Research Center of Ion Beam Technology was founded in 1980 as a part of the centenary celebrations of Hosei University to promote this promising field of research.