Using Expert’s Pcell Feature to Generate Complex Shaped Layers

One of the strengths of Expert is to generate complex shaped layers such as spiral inductors, parabolic waveguides, etc. For the case of the spiral inductor, it has already been well-documented in CELEBRITY example package as “spiral.eld”, from which interested users may learn or use.

In some specific applications, e.g. photonics design, designers may need to generate parabolic-shaped layers such as waveguides. For example, a customer is designing a layer as seen in Figure 1.

Layers like this may appear complicated but by using Expert’s Pcell feature, they can be implemented with ease. The idea is based on using many small rectangles to approximate the actual shape as seen in Figure 2. By choosing a proper resolution, the generated layer will be much closer to the desired shape. The error will be so small that it can be neglected under current process technologies.