DETERMINATION OF CUSTOMIZED COMPONENTS FOR FITTING WAFER PROFILE

摘要

Method and system for defining basis functions for fitting distortions of profiles of objects in a batch, that has undergone a fabrication process, in a manner adaptable to the fabrication process to reduce the errors between profiles approximated with the use of such basis functions and actual object profiles. Process-specific individual basis functions are defined based on spatially-dense measurement of objects from training sub-set of the batch and applying learning algorithm to results of such measurement. Advantages of process-adaptable basis functions over generic basis functions for fitting distortion shapes of objects include higher accuracy of fitting either at larger or a fewer locations across the object.

主权项

1. A method for determining spatial profiles of objects from a set of objects, the method comprising:
with a shape-profiling tool and for each object from a first subset of objects in said set, measuring a corresponding spatial profile at M spatial locations across said object from the first subset
i) to determine a measured spatial profile, andii) to define a pre-determined number of basis spatial functions a combination of which approximates the measured spatial profile of each of the objects from the first set; with the shape-profiling tool and for each object from a second subset of objects in said set, gauging a corresponding spatial profile at a pre-determined number m of spatial locations across the object from the second set to define profile data; and defining an approximated profile for each of objects in the second subset by fitting said profile data with a linear combination of said basis spatial functions.