Heuristic method for dummy fill of chemical mechanical polishing process

Abstract

The invention belongs to the technical field of manufacturing of integrated circuit semiconductor and provides a heuristic method for the dummy fill of a chemical mechanical polishing process. In the method, the dummy fill problem of the minimum dummy metal number is expressed as a standard linear programming problem and then a heuristic algorithm for dynamically increasing the dummy metal density in a grid is provided for solving the minimum dummy fill problem. In the method, the density value of dummy metal filled in the to-be-filled grid is dynamically determined during each optimization process according to a grid density cost function and approximation precision; meanwhile, the increment of the dummy metal density in the grid during each iteration is adjusted through an approximate constant epsilon; thus the compromise of the final result precision and the calculation speed can be realized. The method has high feasibility, extremely high-efficiency processing speed, superior calculation speed and result precision to those of the popular Monte-Carlo method and can be used for solving the large-scale territory dummy fill problem.

Description

technical field [0001] The invention belongs to the technical field of integrated circuit semiconductor manufacturing, and relates to a heuristic method for fast dummy filling with the minimum number of dummy fills as the optimization target while ensuring the uniformity of layout metal density. technical background [0002] With the further development of integrated circuit semiconductor manufacturing technology, the feature size of integrated circuits is further reduced, and the damascene copper interconnection process is widely used in semiconductor manufacturing processes, and has become the mainstream process for multilayer wiring of integrated circuits. In the multi-layer wiring three-dimensional structure of copper interconnection, the high planarization of the chip surface is one of the key technologies. So far, the Chemical Mechanical Polishing (CMP) technology is the only planarization technology successfully and used on a large scale. [0003] One of the biggest ...

AI Technical Summary

Problems solved by technology

In each optimization process, this method can dynamically determine the amount of filling dummy metal density into the grid to be filled according to the grid density cost function and the approximate precision ε, so as to overcome the static filling of dummy metal density in the previous heuristic algorithm The resulting dummy filling quantity is too large or the filling time is too long, making the final result closer to the optimal solution

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