Demonstration of BPM for Non-planar Lithography : Demonstration of BPM for Non-planar Lithography

Requires: SSuprem 4/Optolith
Minimum Versions: Athena 5.22.3.R

This example shows the dose-dependence effect on patterning over a non-planar structure. The structure with symmetrical trench is created and saved in the anopex21.str file for subsequent lithography simulation. Also, the intensity distribution corresponding to a simple layout with the main feature aligned with the center of the trench is calculated and saved in the anopex21_int.str file.

Two separate exposure-bake-development simulation sequences are performed. The first one uses the constant refraction index (n0 = 1.4 + i * 0.02) specified in the OPTICAL statement. In the second simulation the refraction index varies linearly with dose from n0 to n1=1.6 + i * 0.04. The comparison of final structures shows that the "dose effect" could be very strong. In the constant refraction index case the strong reflections from the walls with subsequent "undercut" during development may even result in complete removal of the feature.

To load and run this example, select the Load button in DeckBuild > Examples. This will copy the input file and any support files to your current working directory. Select the Run button in DeckBuild to execute the example.