Abstract. Application of the directed self-assembly of block copolymer to the hole shrink process has gained large attention because of the low cost and high potential for sublithographic patterning. In this study, we have employed a simplified model, called the Ohta-Kawasaki model to find the optimal process conditions, which minimize the morphological defects of the diblock copolymer, PS-b-PMMA. The model parameters were calibrated with cross-sectional transmission electron microscopy images. Our simulation results revealed that it is difficult to eliminate the morphological defects (i.e., PS residual layer) by only varying the shape of the guide hole. It turned out that changing the affinity of the bottom surface of the guide hole from "PMMA attractive" to "neutral" is a more effective way to obtain a reasonably wide, defect-free process window. Note that our simulations are not only computationally inexpensive, but are also comparable to the other detailed models such as the selfconsistent field theory; they may also be feasible for large-scale simulations such as the hotspot analysis over a large area. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

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We investigated the two critical defects on the directed self-assembly hole shrink process, i.e., polystyrene (PS) residue and placement error, by performing dynamic simulations with the Ohta-Kawasaki model. In the simulations, the thermal noise was added to generate stochastic variations in shape and location of the poly(methyl methacrylate) (PMMA) cylindrical domains. For the PS residue issue, we found that the volume fraction of the PMMA minor block, f PMMA , was an effective parameter, and that the PS residue could be minimized by increasing f PMMA from a conventional value of 0.30 to 0.40. On the other hand, the placement error of the PMMA cylindrical domain was affected little by the change in shape and size of the guide hole and by the connectivity to the guide bottom wall. It is speculated that the interfacial stiffness between the PMMA and PS domains would be essential to control the placement error of the PMMA cylindrical domains.