Share Email Print

Proceedings Paper

3D semiconductor grooves measurement simulations (scatterometry) using nonstandard FDTD methods
Author(s): Hirokimi Shirasaki
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

In this paper, we analyze the nonstandard finite-difference time-domain (NS-FDTD) method for the rectangular prismatic and cylindrical medium mounts that are put on the substrate periodically. FDTD is useful for analyzing the light scattering from arbitrary shape grooves and mounts. Using the NS-FDTD algorithms, we can get the deep null in the dispersion error at the design frequency and the error is nearly sixth power of grid size with a same computational cost. First, the 3D NS-FDTD formulation is obtained from Maxwell equation for the conducting medium. We analyze structures of rectangular prismatic and cylindrical mounts on the substrate. We show the propagation characteristic calculated by NS-FDTD. Next, the standard (S) FDTD and NS-FDTD reflectance convergences are checked for the grid size h (=Δx=Δy=Δz) changes. The reflectance is compared with the RCWA results. For the case that the layer lattice and the substrate were the same silicon and had some extinction coefficient, the NS-FDTD reflectance convergences are better than the S-FDTD convergences. Finally, we calculate the reflectance from the cubic and cylindrical periodic mounts put on the silicon substrate.

Paper Details

Date Published: 25 March 2008
PDF: 9 pages
Proc. SPIE 6922, Metrology, Inspection, and Process Control for Microlithography XXII, 69223T (25 March 2008); doi: 10.1117/12.773961
Show Author Affiliations
Hirokimi Shirasaki, Tamagawa Univ. (Japan)

Published in SPIE Proceedings Vol. 6922:
Metrology, Inspection, and Process Control for Microlithography XXII
John A. Allgair; Christopher J. Raymond, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?