Design Driven Dummy Filling

Abstract

Taking into account the constraints introduced by the advanced nodes in use nowadays, this paper describes a new methodology for dummy filling. Using a reliable grid-based engine, this new technique allows the complete customization of the dummy filling process according to design constraints, and even goes one step further, as it is not limited to filling geometries but can be used for many other steps of the whole flow, such as Critical Dimension metrology, Curvilinear drawing of dummy geometries or Guard Ring generation. We will also show, as an added benefit, that giving analog designers full control over dummy filling allows to reduce its impact on the layout performances. This paper first discusses the many benefits of a grid-based strategy for dummy filling, and the dummy map that can be generated as a foundation of further customization. It then introduces the special python environment that allows such customization, with an easy-to-use interface for efficient manipulation. Since the full flow has been implemented, based on existing tools and the python programming language, it demonstrates that the methodology is already operational and well suited for the most advanced technology nodes and large dies. As an example, several applications are considered, based on real use-cases, and sample customization programs are proposed. Benchmarking shows that the run-time performance of the whole engine is extremely interesting, and allows it to be used even in the most demanding cases.