Source/drain optimization of underlapped lightly doped nanoscale double-gate MOSFETs

✍ Scribed by D.H. Tassis; A. Tsormpatzoglou; C.A. Dimitriadis; G. Ghibaudo; G. Pananakakis; N. Collaert

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 650 KB
• Volume: 87
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/j.mee.2010.04.006

✦ Synopsis

The impact of the spacer length at the source (L s ) and drain (L d ) on the performance of symmetrical lightly-doped double-gate (DG) MOSFET with gate length L = 20 nm is analyzed, with the type and doping concentration of the spacers kept the same as in the channel material. Using the transport parameters extracted from experimental data of a double-gate FinFET, simulations were performed for optimization of the underlapped gate-source/drain structure. The simulation results show that the subthreshold leakage current is significantly suppressed without sacrificing the on-state current for devices designed with asymmetrical source/drain extension regions, satisfying the relations L s = L/2 and L d = L. In independent drive configuration, the top-gate response can be altered by application of a control voltage on the bottom-gate. In devices with asymmetrical source/drain extension regions, simulations demonstrate that the threshold voltage controllability is improved when the drain extension region length is increased.