The continued downscaling of silicon CMOS technology presents challenges for achieving the required low power consumption. While high mobility channel materials hold promise for improved device performance at low power levels, a material system which enables both high mobility n-FETs and p-FETs, that is compatible with Si technology and can be readily integrated into existing fabrication lines is required. Here, we present high performance, vertical nanowire gate-all-around FETs based on the GeSn-material system grown on Si. While the p-FET transconductance is increased to 850 µS/µm by exploiting the small band gap of GeSn as source yielding high injection velocities, the mobility in n-FETs is increased 2.5-fold compared to a Ge reference device, by using GeSn as channel material. The potential of the material system for a future beyond Si CMOS logic and quantum computing applications is demonstrated via a GeSn inverter and steep switching at cryogenic temperatures, respectively.

A process for the fabrication of vertical gate-all-around (GAA) nanowire p-FETs with diameters of down to 20 nm based on Ge and GeSn/Ge-heterostructures is presented. The resulting Ge-based devices exhibit a low subthreshold slope (SS) of 66 mV/dec, a low drain-induced barrier lowering of 35 mV/V and an I on/I off-ratio of 2.1×106 for devices with a diameter of 20 nm. Using a GeSn/Ge-heterostructure with GeSn as the top layer and source of the device, the on-current was increased by ~32%. With these results the high potential of incorporation of GeSn into Ge-MOSFET technology is demonstrated.

The continued downscaling of silicon CMOS technology faces big challenges in achieving the required low power consumption. While high mobility channel materials hold promise for improved device performance at low power levels, to date a material system which enables both high mobility n-FETs and p-FETs, that is compatible with Si technology and can be readily integrated into existing fabrication lines is still missing. Here, we present high performance, vertical nanowire gate-all-around FETs based on the GeSn-material system grown on Si. While the p-FET performance is improved by exploiting the small band gap of GeSn as source yielding high injection velocities, the mobility in n-FETs is increased 2.5-fold compared to a Ge reference device, by using GeSn as channel material. The very high potential of the material system for future beyond Si CMOS logic and quantum computing applications is demonstrated via a GeSn inverter and steep switching at cryogenic temperatures, respectively.

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