Orloff, a research specialist in electrostatic optics for field emission ion and electron sources, joined the company as its fourth partner.

[4] FEI's introduction of the liquid metal ion source in 1981 led to its application in the semiconductor industry for mask repair and defect analysis.

[8] On May 27, 2016, Thermo Fisher Scientific Inc. announced[9] its acquisition of FEI Company for US$4.2 billion, which commenced in early 2017.

[11] The FEI trademark was phased out in favor of the Materials & Structural Analysis division of Thermo Fisher Scientific.

The division has research and development centers in Hillsboro, Oregon; Eindhoven, The Netherlands; Munich, Germany; Shanghai, China PRC; Tokyo, Japan; Brno, Czech Republic; Canberra, Australia; Trondheim, Norway; and Bordeaux, France.