Greater process tolerance range using discrete assist features

A method for improving a process margin of a lithographic imaging system comprising: Determining a semi-isolated structure element on a mask as a potential limiting factor for a process tolerance of a lithographic imaging technique (1202, 1204, 1302, 1304); Determining a Auflosungsschwellwertes for imaging technology (1310); and Placing one or more divided assist features having a size below the resolution limit in the vicinity of the semi-isolated mask feature (1212).