Multi-Channel Field-Effect Transistor (MCFET)—Part I: Electrical Performance and Current Gain Analysis

Multi-Channel Field-Effect Transistor (MCFET) structures with ultralow I_OFF (16 pA/mum) and high I_ON (N: 2.27 mA/mum and P: 1.32 mA/mum) currents are obtained on silicon on insulator (SOI) with a high-kappa/metal gate stack, satisfying both low-standby-power and high-performance requirements. The experimental current gain of the MCFET structure is compared with that of an optimized planar FD-SOI reference with the same high-kappa/metal gate stack and is quantitatively explained by an analytical model. Transport properties are investigated, and the specific MCFET electrostatic properties are evidenced, in particular a higher V_Dsat for MCFETs compared with the planar reference. Finally, through 3-D numerical simulations correlated with specific characterizations, the influence of the channel width on the electrical performance is analyzed. For narrow devices, the parasitic bottom channel increases the total drain current of the MCFET structure without degrading the electrostatic integrity.