FEOL is the abbreviation for Front-End Of Line, which is a term used in the semiconductor industry. It refers to the first few stages of the chip manufacturing process, including wafer fabrication, cleaning, and deposition. FEOL is a crucial stage as it affects the performance and reliability of the finished product. There are several synonyms for the word FEOL, including the FrontEnd process, Pre-Patterning, or simply the manufacturing process. Other terms may include the early stages of chip production, wafer manufacturing, or initial processing. Regardless of the term used, FEOL is an essential process that lays the foundation for successful semiconductor manufacturing.