Microprobe

Electron Probe MicroAnalysis (EPMA) is a technique capable of producing chemical analyses of microvolumes at the surface of polished solid samples utilising a fine beam of electrons to bombard the surface of the sample. Since the electron beam may be focused to a diameter of less than 1 micron and penetrates the surface to a depth of only a few microns, analysis of very small sample volumes may be possible in suitable circumstances.