Patent ID: 11972187
Assignee: D2S, INC.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A method for reticle enhancement technology (RET) for a lithographic imaging system, the method comprising:
representing a target wafer pattern or a predicted wafer pattern as a smooth function captured as a function sample array (FSA), wherein the FSA is an array of sampled values of the smooth function, which is a continuous differentiable function;
providing a continuous tone mask (CTM), wherein the CTM is used to produce the predicted wafer pattern, the predicted wafer pattern spanning an entire design area; and
calculating the predicted wafer pattern from the CTM, wherein the calculating comprises:
calculating a cost, the cost being based on comparing the predicted wafer pattern to the target wafer pattern, wherein the cost is represented as a third smooth function; and updating the CTM, using the cost.