Fluorine cold plasmas produced by an electrical discharge in SF₆, CF₄, CHF₃ or C₄F₈ gases, principally, have two main fields of application. The first and historical application is etching of materials for microelectronics and later for micro- and nanotechnology. The second concerns the modification of surface properties, mostly in terms of reflectance and wettability. After an introduction to cold plasmas and plasma–surface interaction principles, the article aims at presenting successively the evolution of fluorine plasma etching processes since the origin with respect to other halogen-based routes in microelectronics, the important and raising application in deep etching and microtechnology, and finally some examples in surface treatment.