Layout optimization of RF CMOS in the 90nm generation by a physics-based model including the multi-finger wiring effect

The multi-finger layout optimization of RF CMOS in the 90nm generation based on a physics-based model is presented. The key features of the physics-based model which was developed are that 1) the transistor model includes a wiring and substrate model of the multi-finger layout, and 2) the physical parameters are adopted from DC measurements and TCAD simulation. By means of a physics-based model, the dependence of ft/fmax on Wf (channel width of one finger) is simulated within 12% accuracy. The dominant parameters of ft/fmax are analyzed by sensitivity analysis. After optimization, fmax experiment data showed a 40% increase (166GHz) from the initial layout