Method and device for determining the contour of spin-coated thin films of material on substrate topography

摘要

A method for determining the contour of a spin-coated thin film of material, such as a photoresist solution, on an uneven topography, such as a patterned semiconductor wafer, utilizes a pattern of features as isolated, raised lines of different widths. The pattern serves to provide frequency weighted parameters used to estimate the coating conformality on both simple and complex topographies. One parameter indicating the contour is independent of coating thickness and the other parameter suggests the range of feature-to-feature interaction inherent in complex topographies. The pattern is useful as a "knock-out" portion of a product wafer to monitor the contour of the coating deposited by spun-coated process steps. Orienting the line pattern in radial and tangential position reveals coating thickness relationships dependent on feature orientation with respect to the centrifugal center of the substrate.