@User, @User: Yes, you have the right idea. "RF" is for "radio frequency" and generally means that the layouts follow best practices for using in RF circuits. But the models themselves are the same; there isn't anything that distinguishes an RF model from a non-RF model; it's all the same model. Consequently, there are "RF" layouts but not "RF" models (except in a couple of cases where there is only one model for a device which has only one RF-optimized layout, so it is effectively an RF model). So for a simple nFET device, you could draw it in Magic as poly over diffusion, and you get an nFET device. But it's not an RF device unless you follow best practices for RF-capable layout.