Some results on yield and local design rule relaxation

The authors study the influence of the line separation in a bus structure on a circuit cost. This structure was selected because it is easy to analyze and yet widely used. Using an analytical model, It is shown that an optimal design rule exists and how the gains obtained by using this optimal design rule depend on the bus length, the defect size distribution exponent and the clustering parameter. Some of the conclusions apply more generally to the problem of realizing design rules in an integrated circuit.