Mask-friendly OPC for a reduced mask cost and writing time

Abstract

In this work, the reduction of the shot count of the mask data is studied. This shot count reduction is achieved by reducing of the number of jogs resulting from the Model-Based Optical Proximity Correction (MBOPC) stage. To reduce the number of OPC-jogs, we study the impact of aligning very small jogs on the shot count as well as their effect on the residual Edge Placement Error (EPE). The OPC-jog alignment phase is made during OPC and not after it, so that the post alignment OPC iterations are responsible for the correction of any residual average EPE resulting from the jogs alignment. The results of this approach show a reduction of the total shot count in the mask fabrication stage by 18%, while the EPE distribution is still almost the same compared to the standard OPC approach, promising for a nice enhancement in the OPC flow to be more fracture friendly expected to decrease the data size of the fracturing, the mask writing time as well as the mask costs.

Mask write time reduction: deployment of advanced approaches and their impact on established work models

“…In this case any changes to the output layout are intrinsically verified against the tolerances required by the litho process. The OPC tools referenced in this study (Calibre OPCpro and Calibre nmOPC) offer two main usercontrolled options to reduce shot count [8,9] : 1. Jog-smoothing -the alignment of adjacent fragments to eliminate vertices prior to the final iterations 2.…”