Some methods for defining design rules

Some new methods to define design rules for integrated-circuits by evaluating a large quantity of results measured from test structures are described. To define the minimum area of a contact hole, more detailed methods are discussed than simple yield analysis: for example, the analysis of the resistances measured or of the local distribution of defects. Using a special test structure of misaligned contact holes, important data for the design rules, such as the alignment tolerance and the mask tolerance, can be defined experimentally.