Novel DPT methodology co-optimized with design rules for sub-20nm device

Because extreme ultra violet (EUV) lithography is not ready due to technical challenges and low throughput, we are facing severe limitation for sub-20nm node patterning even though the extreme resolution enhancement technology (RET) such as the off-axis illumination and computational lithography have been used to achieve enough process window and critical dimension uniformity (CDU). As an alternative solution, double patterning technology (DPT) becomes the essential patterning scheme for the sub-20nm technology node. DPT requires the complex design rules because DPT rules need to consider layout decomposability into two masks. In order to improve CDU and to achieve both design rule simplicity and better designability, we propose two kinds of layout decomposition methodologies in this paper; 1) new mandrel decomposition of the Fin generation for better uniformity, 2) chip-level decomposition and colorless design rule of the contact to improve the scalability. Co-optimized design rules, decomposition method and process requirement enable us to obtain about 6% scaling benefits by comparison with normal DPT flow. These DPT approaches provide benefits for both process and design.