The present disclosure provides one embodiment of an integrated circuit (IC) design method. The method includes receiving an IC design layout having a plurality of main features; applying a main feature dissection to the main features of the IC design layout and generating sub-portions of the main features; performing an optical proximity correction (OPC) to the main features; performing a mask rule check (MRC) to a main feature of the IC design layout; and modifying one of the sub-portions of the main feature if the main feature fails the MRC.