Overlay and semiconductor process control using a wafer geometry metric

摘要

The present invention may include acquiring a wafer shape value at a plurality of points of a wafer surface at a first and second process level, generating a wafer shape change value at each of the points, generating a set of slope of shape change values at each of the points, calculating a set of process tool correctables utilizing the generated set of slope of shape change values, generating a set of slope shape change residuals (SSCRs) by calculating a slope of shape change residual value at each of the points utilizing the set of process tool correctables, defining a plurality of metric analysis regions distributed across the surface, and then generating one or more residual slope shape change metrics for each metric analysis region based on one or more SSCRs within each metric analysis region.

主权项

1. A method for providing a wafer geometry metric, comprising:
acquiring a wafer shape value at each of a plurality of points of a surface of a wafer at a first process level and an additional process level; generating a wafer shape change value at each of the points utilizing the acquired wafer shape value at each of the points at the first process level and the additional process level, the wafer shape change value at each point corresponding to a change in wafer shape between the first process level and the second process level; generating a set of slope of shape change values by calculating a slope of shape change at each of the points utilizing the generated wafer shape change value at each of the points, each of the slope of shape change values corresponding to a slope of the change in wafer shape along at least one direction of the surface of the wafer; calculating a set of process tool correctables utilizing the generated set of slope of shape change values; generating a set of slope shape change residuals (SSCRs) by calculating a slope of shape change residual value at each of the points utilizing the set of process tool correctables; defining a plurality of metric analysis regions distributed across the surface of the wafer, each metric analysis region encompassing one or more points of the plurality of points; and generating one or more residual slope shape change metrics for each metric analysis region based on one or more SSCRs within each metric analysis region.