Detailed Routing Algorithm with Triple Patterning Lithography Constraints
The triple patterning lithography(TPL)technique is a key factor in achieving a reduction in feature size,and is widely recognized as an important advancement in the field.However,the layout decomposition problem in TPL presents a unique challenge.To address this challenge,a novel detailed routing algorithm based on TPL constraints has been proposed.By transforming the layout decomposition problem into a detailed routing problem that satisfies the same color spacing and minimum spacing constraint,the algorithm ensures the use of a grid encoding method that meets the spacing constraints.The Hannan grid,in conjunction with the spacing constraints,is utilized to optimize the routing resources utilization and speed,which has a significant impact on the overall effectiveness of the algorithm.To facilitate multi-terminal routing,the algorithm employs the multi-source Dijkstra algorithm to search for the shortest path.The results are then decomposed and col-ored to minimize the number of conflicts and stitches.The findings demonstrate that when contrasted with conventional detailed routing,the proposed approach can significantly mitigate conflicts by approximately 60%and minimize stitches by 70%.