Substrate matrix to decouple tool and process effects
AssigneeKLA-Tenor Corporation
InventorsPavel Izikson, Michael E. Adel, Daniel Kandel
Life of this patent
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Abstract
A method of characterizing a process by selecting the process to characterize, selecting a parameter of the process to characterize, determining values of the parameter to use in a test matrix, specifying an eccentricity for the test matrix, selecting test structures to be created in cells on a substrate, processing the substrate through the process using in each cell the value of the parameter as determined by the eccentric test matrix, measuring a property of the test structures in the cells, and developing a correlation between the parameter and the property.
Claims20
A method of characterizing a process, the method comprising the steps of:
- selecting the process to characterize,
- selecting a parameter of the process to characterize,
- determining values of the parameter to use in a test matrix,
- specifying an eccentricity for the test matrix,
- selecting test structures to be created in cells on a substrate,
- processing the substrate through the process using in each cell the value of the parameter as determined by the eccentric test matrix,
- measuring a property of the test structures in the cells, and
- developing a correlation between the parameter and the property.
A method of characterizing a photolithography process, the method comprising the steps of:
- determining values of focus and exposure to use in a test matrix,
- specifying one of a random and pseudo-random eccentricity for the test matrix,
- selecting a test structure having a line width to be created in cells on a substrate,
- processing the substrate through the photolithography process using in each cell a combination of values of the focus and the exposure as determined by the eccentric test matrix,
- measuring the line widths of the test structures in the cells, and
- developing a polynomial expression that correlates the focus and exposure as input variables with the line width as output variable.
Dependencies are inferred from the claim text.