Structure Effects in the gate-all-around Silicon Nanowire MOSFETs

We theoretically examine the structure effects (cross-section shape, channel orientation and the size of nanowires) of the gate-all-around silicon nanowire metal-oxide-semiconductor field-effect- transistors (MOSFETs) on their ultimate performance. Among these different types of silicon nanowire MOSFETs, the rectangular nanowire MOSFETs present the best device performance in terms of the ON-state currents with the consideration of the fixed nanowire size. However, the triangular nanowire MOSFETs show the largest bandgap change caused by the quantum confinement effects, indicating the largest V_T variations. As the size of the nanowire decreases, the quantum effects play the more important role in the device performance, for example, the significant performance enhancements in the P-type MOSFETs due to carrier effective mass changes in P-type Si nanowire MOSFETs.