The use of ionic liquid ion sources (ILIS) in FIB applications

A new monoenergetic, high-brightness ion source can be constructed using an arrangement similar to liquid metal ion sources (LMIS) by substituting the liquid metal with an ionic liquid, or room temperature molten salt. Ion beams produced by these ionic liquid ion sources (ILIS) have energy deficits and distributions that closely resemble their metallic counterparts, with the exception that, if needed, they can be stably operated at current levels as low as a few nA. ILIS sources are here presented as having two further key advantages: (1) the ability to obtain both positive and negative ion beams, and (2) the ability to produce very diverse molecular ions in terms of their masses, compositions and properties, due to the fact that the number of available ionic liquids is large. In this thesis an overview of ILIS sources is presented, as well as preliminary results of their performance in a FIB column. Thesis Supervisor: Paulo Lozano Title: Professor

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