Enhancement of correction for mask process through dose correction on already geometrically corrected layout data

Mask manufacturing using E-Beam at 32 nm process node and below is failing to meet CD uniformity, CD linearity requirements due to the inherent systematic errors in the e-beam process. MPC-GC (Mask Process Correction through Geometric correction) is one technique, which moves the edges of input shapes inwardly or outwardly to compensate for the systematic errors. Since, geometric correction is done under some constraints there will always be further scope to improve the intensity profile of the mask layout to achieve better fidelity. In this paper, we discuss about an MPC flow to further enhance fidelity of the patterned shapes on the mask by adding dose correction on top of the geometric correction. We have developed NxMPC-DC tool as part of NxMDP 1 tool suite to achieve the above mentioned objective. If the input layout data is not fractured already, NxMPC-DC will use NxFracture 2 to carry out fracturing and then assign modulated dose values to the shots. NxMPC-DC would take the same mask process model as the one used for NxMPC-GC. Hence, in this proposed flow, the fidelity of the simulated contour would only improve beyond the MPC-GC corrected data as there would not be any conflict between the mask process models used for geometric and dose based corrections.