Abstract: An apparatus for directly measuring performance offset of NFET transistors with respect to PFET transistors in CMOS device processing includes a ring oscillator whose frequency is used to measure random across chip variations, as well as correlated across chip variations; a balanced inverter having a input driven by the ring oscillator, wherein the balanced inverter is designed to be formed such that a current drive capability of one or more NFET devices of the inverter is substantially equal to a current drive capability of one or more PFET devices of the inverter at a given operating temperature; and a capacitor coupled to an output of the inverter, with a voltage across the capacitor indicative of whether a skew exists between NFET device performance and PFET device performance.

Abstract: A method using a generate-and-verify computer program product to generate by repetitive passes a design rules checking computer program, wherein the design rules are described in a file called a runset. The design rules checking program is used for exhaustive testing of VLSI chips for compliance to the design rules of a given VLSI fabrication process. The runset is repeatedly iterated in loop fashion with respect to a testcase file containing groups of layout structures or shapes used for verifying the correctness of the runset. A general purpose shapes processing program creates an error shapes file for storing geometrical errors found in each said layout structure. Two additional shapes are used in the verification process: user boundary shapes for defining areas in which errors are not to be detected for a given design rule, and automated boundary shapes created to surround each said layout structure with a boundary that defines regions where error shapes can occur.