3-D Integrated Track-and-Hold Circuit Using InAs Nanowire MOSFETs and Capacitors

This letter presents a vertical integration scheme where track-and-hold circuits, consisting of a MOSFET in series with a metal–insulator–metal (MIM) capacitor, are successfully fabricated along vertical InAs nanowires. The nanowire MOSFET is used as a switch with varying switch resistance, ${R}_{sw}$ , as the gate-source voltage, ${V}_{\mathrm{GS}}$ , is varied. The track-and-hold circuit operation is verified by a sine wave that is properly evaluated by the circuit. In addition, calculations show that the three-dimensional integration reduces the track-and-hold area a factor of 2, as compared with planar MIM capacitor only. With further nanowire pitch reduction, about ten times area saving is projected.