OPTICAL LENS TESTING USING OPTICAL TRANSFER FUNCTION DATA AND IMAGE SIMULATION
Original Publication Date: 1992-May-01
Included in the Prior Art Database: 2002-Jan-04
Lithography is one of the gating technologies restricting the evolution to larger integrated circuits with more densely packed finer features. The image transfer from a mask or reticle onto the wafer has components of image quality (i.e., the shape and size of the imaged features) and image placement (i.e., the overlay of the previous layers with the current one). The printing equip- ment includes steppers, scanners, and step-and-scan machines. Manufacturing engineering attempts to exer- cise control of the printers within design tolerances so it is critical to evaluate new equipment performance comprehensively to confmn that it can enter manufac- turing withii specfication and without contributing imag- ing defects.