US 12,093,633 B1
Method for extracting parasitic capacitance of interconnection lines of integrated circuit based on discontinuous Galerkin finite element method
Zhikuang Cai, Jiangsu (CN); Hang Yang, Jiangsu (CN); Zhenghao Zhao, Jiangsu (CN); Hongqiang Zhu, Jiangsu (CN); Henglu Wang, Jiangsu (CN); Jingjing Guo, Jiangsu (CN); Jiafei Yao, Jiangsu (CN); and Yufeng Guo, Jiangsu (CN)
Assigned to Nanjing University Of Posts And Telecommunications, Jiangsu (CN); and NANTONG INSTITUTE OF NANJING UNIVERSITY OF POSTS AND TELECOMMUNICATIONS CO., LTD., Jiangsu (CN)
Appl. No. 18/022,272
Filed by Nanjing University Of Posts And Telecommunications, Jiangsu (CN); and NANTONG INSTITUTE OF NANJING UNIVERSITY OF POSTS AND TELECOMMUNICATIONS CO., LTD., Jiangsu (CN)
PCT Filed May 27, 2022, PCT No. PCT/CN2022/095540
§ 371(c)(1), (2) Date Feb. 21, 2023,
PCT Pub. No. WO2023/173592, PCT Pub. Date Sep. 21, 2023.
Claims priority of application No. 202210263251.3 (CN), filed on Mar. 17, 2022.
Int. Cl. G06F 30/39 (2020.01); G06F 17/12 (2006.01); G06F 30/392 (2020.01); G06F 30/398 (2020.01); G06F 111/10 (2020.01)
CPC G06F 30/398 (2020.01) [G06F 17/12 (2013.01); G06F 30/392 (2020.01); G06F 2111/10 (2020.01)] 10 Claims
OG exemplary drawing
 
1. A method for extracting parasitic capacitance of interconnection lines of integrated circuits based on discontinuous finite element method, comprising:
dividing an integrated circuit layout into non-uniform grids according to a distribution situation of conductors to obtain a grid form that is uniform and dense close to boundaries of the conductors and is non-uniform and sparse away from the boundaries of the conductors;
determining whether each grid cell is a boundary cell, marking each grid cell with a global number, assigning grid cells which are non-boundary cells with numbers of cells to be solved, and establishing a mapping relationship between global numbers and the numbers of the cells to be solved, the grid cells which are non-boundary cells forming a region to be solved, and the boundary cells being grid cells outside the boundaries of the region to be solved and grid cells in a region where the conductors are located;
initializing freedom degrees of potentials of boundary cells, simplifying an electrostatic field strength formulae in a local discontinuous finite element format according to whether an adjacent grid cell of each grid cell in the region to be solved is a boundary cell to obtain a linear system of equations in the form of A*u=b, and solving the linear system of equations to obtain a freedom degree vector u of a potential function composed of the freedom degrees of potentials of all grid cells to be solved, A representing a sparse matrix, and b representing a constant vector generated in the process of simplifying the electrostatic field strength formulae in the local discontinuous finite element format;
solving a freedom degree vector of an electric field strength function composed of the freedom degrees of potentials of all grid cells to be solved according to the electrostatic field strength formulae in the local discontinuous finite element format and the freedom degree vector of potential function composed of the freedom degrees of potentials of all grid cells to be solved; and
selecting a Gaussian surface according to the distribution situation of conductors, performing integration of an electric field strength function on the Gaussian surface to obtain the quantity of electric charge of the conductors, and obtaining capacitance of the conductors and the parasitic capacitance between interconnection lines of the conductors according to the relationship between the quantity of electric charge and capacitance of the conductors.