Still referring to FIG. 2, the fin 110 includes two source/drain (S/D) regions 110a and a channel region 110b between the two S/D regions 110a. The S/D regions 110a and the channel region 110b are arranged horizontally along the “y” direction. In the illustrated embodiment, the fin 110 has a substantially rectangular profile in the “x-z” plane. The width of the fin 110 along the “x” direction is denoted as Wfin. The fin 110 has a height Hfin above the isolation structure 112 along the “z” direction. In alternative embodiments, the fin 110 has a trapezoidal profile in the “x-z” plane, and the fin width Wfin is measured at the middle (Hfin/2) of the fin 110. In embodiments, the fin width Wfin may be 10 nanometers (nm) or smaller, such as 6 nm or smaller. In embodiments, the fin height Hfin may be equal to or greater than 30 nm, such as 40 nm or greater, or even 50 nm.
