Background and Objectives: In this work, a dual workfunction gate-source pocket-retrograde doping-tunnel field effect transistor (DWG SP RD-TFET) is proposed and investigated.
Methods: The dual workfunction gate-source pocket-retrograde doping-tunnel field effect transistor is a Silicon-channel TFET with two isolated metal gates (main gate and auxiliary gate) and a source pocket in the channel close to the source-channel junction to increase the carrier tunneling rate.
Results: For further enhancement in the tunneling rate, source doping near the source-channel junction, i.e., underneath the auxiliary gate is heavily doped to create more band bending in energy band diagram. Retrograde doping in the channel along with auxiliary gate over the source region also improve device subthreshold swing and leakage current. Based on our simulation results, excellent electrical characteristics with ION/IOFF ratio > 109, point subthreshold swing (SS) of 6 mV/dec and high gm/ID ratio at room temperature shows that this tunneling FET can be a promising device for low power applications
Conclusion: In order to increase the ON-current in this device, we utilized several methods including incorporation of high-K material in top oxide, source pocket in channel and a thin auxiliary gate with high workfunction over the source region. Incorporating auxiliary gate over the source also caused a barrier formation in the energy band diagram profile of this device which it leds electron concentration in the channel, subthreshold swing and OFF-current to be reduced.