Slit emitter Liquid metal ion sources (LMIS) based on field ionization or field evaporation were introduced in the late '60s and quickly became widespread as simple, cheap ion sources for a number of applications, and in 1972 the European Space Agency started development on an electric propulsion system based on the field emission principle using liquid metal ion sources. The use of LMIS operated on gallium, indium, alkali metals or alloys has also been standard practice in secondary ion mass spectrometry (SIMS) since the 1970s.
Slit emitter Liquid metal ion sources (LMIS) based on field ionization or field evaporation were introduced in the late '60s and quickly became widespread as simple cheap ion sources for a number of applications and in 1972 the European Space Agency started development on an electric propulsion system based on the field emission principle using liquid metal ion sources The use of LMIS operated on gallium indium alkali metals or alloys has also been standard practice in secondary ion mass spectrometry (SIMS) since the 1970s