what is feol vs beol front end back end of line

Two halves of chipmaking: FEOL = Front-End-Of-Line — building the TRANSISTORS in the silicon: well/isolations, gate, source/drain, transistor-level films. BEOL = Back-End-Of-Line — building the INTERCONNECTS on top: the metal lines, vias, barriers, dielectrics that wire the transistors together. The one-line frame: 'FEOL builds the switches, BEOL wires them together.' WHY IT MATTERS FOR THIS ROLE: the metal-deposition group is primarily BEOL — the metal interconnect films (copper, tungsten, barriers/liners). But some metals are also used in FEOL (contacts, gate metals). Knowing which side your group's products sit on shows you understand where your work fits. Say: 'This group's metal deposition is mostly BEOL interconnect films, which is where the copper lines and their barriers live.' It proves orientation, not just vocabulary.