Front end of line


The front-end-of-line is the first portion of IC fabrication where the individual devices are patterned in the semiconductor.
FEOL generally covers everything up to the deposition of metal interconnect layers.
For the CMOS process, FEOL contains all fabrication steps needed to form fully isolated CMOS elements:
  1. Selecting the type of wafer to be used; Chemical-mechanical planarization and cleaning of the wafer.
  2. Shallow trench isolation
  3. Well formation
  4. Gate module formation
  5. Source and drain module formation