Methods are presented for facilitating fabricating stacked nanowire, field-effect transistors. The methods include: forming a cut mask spacer on a gate structure disposed above multiple layers above a substrate structure, the gate structure including a sidewall spacer along its sidewalls, and the cut mask spacer overlying the sidewall spacer; defining a stack structure by cutting through the multiple layers using the cut mask spacer and gate structure as a mask, and selectively etching at least one layer of the multiple layers to undercut, in part, the mask, where at least one other layer of the multiple layers remains un-etched by the selectively etching; and providing an alignment mask spacer over the gate structure and over end surfaces of the multiple layers below the gate structure, the alignment mask spacer facilitating etching the other layer(s) of the multiple layers to selectively expose, in part, end surfaces of the other layer(s).