Dainty, “Linnik microscope imaging of integrated circuit structures

Conventional scalar imaging theory has been used successfully to provide measurements of linewidths sults. To investigate further the validity of the waveguide model, a primary measurement systemon photomasks and thin wafers1 1#200 nm2. An important part of this process is the use of a primary linewidth-measurement system to allow measure-ments to be made on real samples under well-characterized conditions consistent with those im-plied by the theory. Such systems have been developed at both the National Institute of Science and Technology in the U.S.A.1,2 and at the Nationa