This paper demonstrates the design strategy in the self-aligned quantum-well InAs MOSFETs with T-shape S/D. A 2-D TCAD simulation is performed based on the experimental data. The effect of air gap between the T-shape metal contacts is taken into account. It is found that the fringing effects induced by the air gap has significant impacts on both DC and RF performances. Further study is carried out based on this TCAD simulation platform. The channel extension region, which is simply considered as part of series resistances, needs to be properly designed to maximize fT and fMAX. RF performances can't be further improved even if the gate length is aggressively scaled down. However, the reduction of contact resistance can improve fT and fMAX without any limitations. This contact resistance reduction can be realized by incorporating the additional annealing process in the self-aligned gate-last T-S/D process.
- InAs self-aligned MOSFET
- Nano-scaled transistor AC simulation
- RF parameters
- Parasitic elements