Patent ID: 6455332
Filing Date: 2002-09-24
Classification: H01L

Abstract:
A method for calibrating a line width measurement metrology tool set over time, comprising:using a reference wafer to calibrate a first tool set at a first time period, the reference wafer, including a substrate layer, an insulating layer formed over the substrate layer, a feature formed over the insulating layer, and at least one conductive path coupling at least a portion of the feature to the substrate layer, the at least one conductive path providing a path to dissipate charge from the at least a portion of the feature to the substrate layer, the substrate layer acting as a ground for the reference wafer; using data obtained from the reference wafer to calibrate the first tool set at a second time period; and using the data obtained from the reference wafer to calibrate a plurality of tool sets, wherein the calibration data for each tool set can be used to cross-reference each tool set with respect to the others.