摘要:
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. An association table is created which is a compilation of the error shapes, user boundary shapes, and automated boundary shapes associated with each layout structure. The association table is processed to determine the correctness of the runset. The runset is modified to correct each valid error. The repetitive passes continue until a final runset is generated. This final runset becomes the input to design rules checking computer program product and customizes the program for a given VLSI fabrication process.
摘要:
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.