How do you optimize the common centroid layout for a differential pair when dealing with multi-finger Transistors?

I always ensure perfect symmetry by using an ABBA or AABB common centroid pattern for multi-finger differential pairs. But in ultra-deep submicron processes, stress effects become significant. To tackle this, I insert dummy fingers at the edges to balance mechanical stress and ensure uniform device matching. Also, using dummy poly and dummy diffusion around the active area helps reduce process variation effects. You should also check the OD spacing and diffusion jogs, as improper design can lead to systematic mismatches that degrade performance.

Also We can try with Interdigitated pattern for Current mirror pairs.