An integrated circuit includes first and second semiconductor fins, first and second epitaxy structures, and first and second dielectric fin sidewall structures. The first and second epitaxy structures are respectively on the first and second semiconductor fins. The first epitaxy structure and the second epitaxy structure are merged together. The first and second dielectric fin sidewall structures are respectively on opposite first and second sidewalls of the first epitaxy structure. The first sidewall of the first epitaxy structure faces the second epitaxy structure. The first dielectric fin sidewall structure is shorter than the second dielectric fin sidewall structure.