g 2 D ( r -> ) = g 2 D ( ??? r -> ??? ) = 2 ?? ??? 0 ??? ??? vvJ 0 ( 2 ?? ??? r -> ??? v ) MTF ( v ) , Equation 42 where g2D({right arrow over (r)}) is the exposure response of the resist, and more particularly, the exposure response at a plane in the resist stack structure, and J0 is a Bessel function.