Hints, Tips and Solutions
Adding Random Noise to Mask Layout
Introduction
Geometrical module of Victory Process allows the fast and accurate transfer of mask patterns to the structure. However, sometimes it is necessary to emulate the imperfections of physical processes while retaining the speed and accuracy of the geometrical approximation. For example, you may want to test the tolerance of the final device to random fluctuations in structure’s geometry.
With Victory Process you can achieve this by adding the random noise to the existing mask layout and using the resulting mask in further process simulation steps.
Algorithm
Victory Process allows you to create a new mask layout based on the existing one by adding a random noise with given amplitude and frequency to layout’s edges. The following algorithm is used:
- Each side of the polygon(s) forming the layout is divided into intervals based on noise frequency;
- Each interval is split in two by inserting a single random point;
- Newly inserted point is shifted in direction orthogonal to original polygon’s side either inwardly or outwardly. The shift distance is a random number between zero and half of the given amplitude;
The newly generated perturbed mask is then added to the layout and can be used in subsequent simulation steps.
