Impact of the Zn diffusion process at the source side of InXGa1-XAs nTFETs on the analog parameters down to 10 K

Abstract

In this work, the impact of the Zn diffusion processes in the source and the amount of Indium for InxGa1-xAs nTFET was analyzed, focusing on the basic analog parameters. Three different splits were analyzed: In0.53Ga0.47As with Spin-on-Glass (SoG) Zn diffusion in the source, In0.7Ga0.3As using SoG and In0.53Ga0.47As with Gas Phase Zn diffusion in the source. The ION increase of the Gas Phase device can be related to its higher source/channel junction abruptness that also reduces the tunneling length. The Gas Phase device has presented better subthreshold swing, which increases the transistor efficiency in the weak conduction regime. The Gas Phase device presents the lowest intrinsic voltage gain (AV) for high gate voltage (V-GS) values due to its significant output conductance (gD) degradation. However, the reduction of the temperature affects more gD than gm, resulting in an improvement of AV by more than 20 dB at 10 K for the Gas Phase device compared to both SOG splits.