@User @User i have included this ft simulation example in the xschem_sky130 repository, it's an interesting test case. Thanks Rafael!. I have made some little changes: 1. used lvt transistors, these have lower threshold and frequency limit can be pushed a little higher. 2. i have set the idref biasing current on the drain side so both transistors have same vgs and same vbs. Picture below shows ft and also vgs. This shows that with 1V Vgs we are already close to 120GHz.