A new complementary hetero-junction vertical Tunnel-FET integration scheme

This paper presents a new integration scheme for complementary hetero-junction vertical Tunnel FETs (VTFETs), whereby a sacrificial source layer is used during the device fabrication and replaced by the final hetero-source materials, respectively for n- or p-TFETs, thereby minimizing the thermal budget applied to the source junctions. With the demonstration of this source-replacement-last module for a vertical Ge hetero-junction n-TFET, we show that it is possible to grow highly doped hetero-junctions on a Si channel with steep doping profiles and without damaging the high-κ gate-dielectric interface. This scheme allows for the integration of complementary low-bandgap materials on a Si platform providing high on-currents combined with the Si channel based low off-currents.