使用嵌段共聚物(block copolymers, BCP)的定向組裝技術 (Directed self-assembly, DSA)已經是一項具有發展性的光刻技術，可以在集成電路上生成微小的圖像。現今已經有許多研究探討使用圓柱型式BCP製作金屬穿孔/接點層的設計方法。然而，圓柱型式BCP受限於生成孔洞的固定間距和導向模板的位移誤差(guiding template distortions, GTD)。因此，只有很少的可行孔洞圖案可以使用模板進行製造，而且不良的成品仍然也是主要問題之一。另一方面，使用片狀型式BCP的層狀DSA成為另一種可用於生成孔洞的方法，該方法與自對準孔(self-aligned via, SAV)技術相結合，可避免孔位移誤差並生成各樣的線性孔洞圖案。在本篇，我們是第一篇提出使用SAV技術和多圖案微影技術(multiple patterning lithography, MPL)的層狀DSA導向模板設計。我們分別提出基於整數線性規劃(integer linear programming, ILP)的方法和啟發式方法，並且有考慮SAV技術的層狀DSA的設計約束。實驗結果證明了基於ILP的方式是最佳的，並且啟發式方法還可以有效地近似最佳解。

Directed self-assembly (DSA) with block copolymers (BCP) has become a promising lithography technology for generating tiny features in integrated circuits. There have been many existing studies investigating the design methodologies using cylinder-forming BCP for via/contact layer manufacturing. However, cylindrical DSA suffers from the limited natural pitch of generated holes and the displacement errors due to guiding template distortions. Consequently, only few feasible hole patterns are manufacturable with a template and the unsatisfactory yield is still one of the major concerns. On the other hand, lamellar DSA using lamella-forming BCP emerges as another solution for hole generation, which in combination with the self-aligned via (SAV) process is immune to hole displacement errors and able to produce various linear hole patterns. In this paper, we propose the first work of guiding template design for lamellar DSA by using the SAV process and multiple patterning lithography (MPL). An integer linear programming (ILP)-based approach and a heuristic method are respectively proposed that consider the design constraints induced by lamellar DSA with SAV. Experimental results demonstrate the optimality of the ILP-based approach, and the heuristic method can also efficiently derive near-optimal solutions.

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