OPC correction method for improving hot spots in contact hole process through sub-resolution auxiliary graphics

Abstract

The invention discloses an OPC correction method for improving hot spots in contact hole process through sub-resolution auxiliary graphics. The OPC correction method comprises the following steps: step 1, OPC correction is performed on the original photolithography layout graphics, the contact hole graphics of which the photolithography simulation value deviates from the target value is screened out and the positions of the process hot spots are marked; step 2, the spatial orientation of the scattering strip of the sub-resolution auxiliary graphics near the positions of the process hot spot graphics is checked and the spatial orientation of the scattering strip forming the sub-resolution auxiliary graphics as a first direction; step 3, the spatial orientation of the sub-resolution auxiliary graphics near the process hot spot graphics is changed and the first direction of a part of scattering strips is rotated to the second direction; and step 4, OPC correction is performed on the contact hole layout graphics again to obtain the final mask template layout and the OPC correction effect is checked by using optical simulation again. The graphic defects generated by the limitation of the minimum size rule of the mask template in the contact hole layout graphics can be reduced, the process hot spots can be eliminated and the device performance can be improved.

Description

technical field [0001] The invention relates to the field of semiconductor device manufacturing technology, in particular to an OPC correction method for improving hot spots in contact hole technology through sub-resolution auxiliary patterns. Background technique [0002] In the semiconductor manufacturing process, as the process node becomes smaller and smaller, the layout pattern density will become higher and higher. This phenomenon is particularly evident in the pattern of contact holes connecting the front and rear segments. In order to better transfer the integrated circuit pattern on the mask to the silicon wafer through the exposure of a photolithography machine, it is often necessary to use an optical proximity correction (OPC: Optical ProximityCorrection) method to correct the layout pattern on the mask. [0003] Since the mask plate will be restricted by MRC (Mask Rule Constraint, minimum size rule restriction) when making the mask plate, OPC will also be limite...

AI Technical Summary

Problems solved by technology

[0007] 1. Using sub-resolution graphics assistance (SRAF), the disadvantage is that it is easy to fail when the graphics density is too high;

[0008] 2. After the edge cutting and segmenting of the contact hole layout graphics, the disadvantage is: the prediction ability of the OPC model is reduced;

[0009] 3. Changing the target value of the layout graphics needs to be corrected. The disadvantage is: the process window is reduced

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