Abstract

We have carried out a rigorous electromagnetic analysis of nm-linewidth, sub- μ-m period, rectangular semiconductor gratings based on the Modal theory of square-profiled gratings^1,2 using exact ei- gensolutions in the grating region. As opposed to the traditional rigorous coupled wave analysis,³ the modal analysis allows us to analyze the role of each eigenfunction and provides much greater physical insight with comparable computational difficulty. These studies are important for understanding the electromagnetic response of quantum scale semiconductor structures, such as the ~10-nm-wide, 300- run period, 2-pm-deep Si gratings we have reported.⁴

© 1996 Optical Society of America