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Unigit Grating Solver Software

Development and Projects

UNIGIT is a universal grating solver that is based on three solving methods:

‐ the Rigorous Coupled Wave Approach (RCWA) for 1D and 2D (non-orthogonal) gratings in classical and conical mount,
‐ the Rayleigh Fourier Method for 1D gratings,
‐ the Coordinate Transformation Method a.k.a. Chandezon Method for 1D gratings and 2D gratings in classical and conical mount.
In addition, the solving methods are embedded in a recursive S-matrix scheme preventing ill conditioning. This matrix scheme permits the step-by-step solution of general layer stacks.

In order to speed up time consuming computations with loops or high truncation order in 2D, the following acceleration techniques are implemented:
- Parallel Loop: max acceleration factor = # of processor cores,
- Smart Order for 2D: acceleration factors up to 4x ... 8x ... even beyond,
- Symmetry oblique for 2D (Grating and incidence have to be symmetric to one axis): max acceleration factor = 4x (8x for only one polarisation),
- Symmetry normal for 2D (Grating has to be symmetric to x- and y-axis and normal incidence): max acceleration factor = 32x (64x for only one polarisation).

A general layer stack can comprise different layer types.
All available layer types are detailed in the following manuals -
- UNIGIT Manual for Version 2.02.01: unigit_manual_v20202.htm
- UNIGIT Manual for Version 2.02.02: unigit_manual.pdf