Calibration and impact of bulk trap-assisted tunneling and Shockley-Read-Hall currents in InGaAs tunnel-FETs

Published

September 1, 2017

Author(s)

Quentin Smets, Anne S. Verhulst, Eddy Simoen, David J. Gundlach, Curt A. Richter, Nadine Collaert, Marc Heyns

Abstract

The tunnel-FET (TFET) is a promising candidate for future low-power logic applications because it enables a sub-60 mV/dec subthreshold swing. However, most experimental TFETs are plagued by unwanted trap-assisted tunneling (TAT) and Shockley-Read-Hall (SRH) generation currents, which degrade the swing and increase the leakage floor, hence forming a major roadblock for TFET adoption. It is still unclear which type of traps causes this degradation. In this letter, we calibrate TAT and SRH caused by bulk traps with the help of In0.53Ga0.47As p+/n+ and p+/i/n+ diodes on lattice matched substrates. Using these calibrated models, we then make performance predictions for an In0.53Ga0.47As TFET. We find that the bulk SRH and TAT currents are sufficiently low compared to the target off-state current and hence not a significant issue. Therefore it is likely that the degradation commonly observed in experimental In0.53Ga0.47As TFETs on lattice matched substrates is not caused by bulk semiconductor defects, but by semiconductor/oxide interface defects.

Citation

IEEE Electron Device Letters

Volume

64

Issue

9

Pub Type

Journals

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DOI Link

Keywords

nanoelectronics, tunnel-FETs, TFET, tunnel diode, low-energy computing, Shockley-Read-Hall, SRH

Citation

Smets, Q. , Verhulst, A. , Simoen, E. , Gundlach, D. , Richter, C. , Collaert, N. and Heyns, M. (2017), Calibration and impact of bulk trap-assisted tunneling and Shockley-Read-Hall currents in InGaAs tunnel-FETs, IEEE Electron Device Letters, [online], https://doi.org/10.1109/TED.2017.2724144 (Accessed October 8, 2025)