Improved design of 5 nm class electron optical microcolumn for manufacturing convenience and its characteristics

The achievement of small probe beam size at a target plane with higher probe beam current is an important challenge in the development of electron beam equipment, such as an electron optical microcolumn. Though ∼10 nm class probe beam size with acceptable current was reported already, it was achieved through a series of sophisticated technologies. In this work, the authors would like to report on the improved design of a ∼5 nm class electron optical microcolumn which can be assembled through relatively convenient manufacturing processes. The advantage of the improved design is that it can mitigate the complexities in its manufacturing processes by simply enlarging the aperture diameter of an extractor electrode and inserting an additional subsidiary electrode. The design parameters and the results of analysis on the performance of the improved electron optical microcolumn will be discussed through simulation investigation.