Method for modifying a chip layout to minimize within-die CD variations caused by flare variations in EUV lithography
AssigneeIntel Corporation
InventorsVivek K. Singh, John Ernst Bjorkholm, Francisco A. Leon
Life of this patent
Estimating the term…
Abstract
A method including determining a first flare convolution based on a feature density of projected structures on a substrate layout, determining a second flare convolution based on a mask for a given substrate layout, determining a system flare variation by summing the first flare convolution and the second flare convolution, and determining a critical dimension variation based on the system flare variation.
Claims15
A method comprising:
- determining a first flare convolution based on a feature density of projected structures on a substrate layout, calculated on a coarse grid over a unit area;
- determining a second flare convolution based on a feature density of projected structures on a substrate layout, calculated on a fine grid over the unit area;
- determining a system flare variation by summing the first flare convolution and the second flare convolution;
- and
- determining a critical dimension variation based on the system flare variation.
A method comprising:
- determining a first convolution of a point spread function according to a first grid density of projected structures on a substrate, the first grid density selected to account for at least a majority of a flare variation about a point on the substrate;
- determining a second convolution of a point spread function according to a second grid density of projected structures on the substrate, the second grid density selected to account for at least a majority of a flare about a point on the substrate;
- determining a flare variation for an area of the substrate by adding a result of the first convolution and the result of the second convolution;
- and
- determining a critical dimension variation based on the flare variation.
A machine readable storage media containing executable program instructions which when executed cause a digital processing system to perform a method comprising:
- determining a first convolution of a point spread function according to a first grid density of projected structures on a substrate, the first grid density selected to account for at least a majority of a flare variation about a point on the substrate;
- determining a second convolution of a point spread function according to a second grid density of projected structures on the substrate, the second grid density selected to account for at least a majority of a flare about a point on the substrate;
- and
- determining a flare variation for an area of the substrate by adding a result of the first convolution and the result of the second convolution.
Dependencies are inferred from the claim text.