Reducing Ambipolar Current in Germanene Nanoribbon Tunneling Field Effect Transistor (GeNR-TFET) using Gate-Drain Overlap and Decreasing Doping Density in the Drain Side

Document Type : Original Article

Authors

1 Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan, Iran

2 Department of Electrical and Computer Engineering, University of Kashan, Kashan, Iran

3 Technical and Vocational University, Kashan, Iran

Abstract

In this research, we investigate the ambipolar current in germanene nanoribbon tunneling field effect transistor (GeNR-TFET) using combination of density functional theory (DFT) and non-equilibrium Green’s function method (NEGF). We propose two different methods to reduce the ambipolar current in the GeNR-TFET: using overlapped gate metal to cover part of the drain side and the other idea is to decrease the doping density in the drain side. The results show that by extension of the metal gate on the drain region, the hole current from the drain to channel reduces and it is possible to reduce this current more by using longer overlapping length. Also, results prove that by decreasing the doping density in the drain side compared with the source region, the ambipolar current declines. We obtain that by mixing two proposed ways, the ambipolar current can significantly be reduced. Suppression of this ambipolar current is an important challenge in digital circuit design.

Keywords


[1]      مهسا مهراد و میثم زارعی، «ارائه ساختار نوین ترانزیستور اثر میدان سیلیسیم روی عایق دو گیتی با پنجره اکسید در درین گسترده شده به منظور کاربرد در تکنولوژی نانو» مجله مهندسی برق دانشگاه تبریز، جلد 47، شماره 2، صفحات 727-733، 1396
[2]      حامد نجفعلی زاده، علی اصغر اروجی، «طراحی ساختاری از ترانزیستور ماسفت دوگیتی با به کارگیری دو ماده، اکسید هافنیوم(HfO2) و سیلیسوم-ژرمانیوم (SiGe) در کانالی از جنس سیلیسیم (DM-DG)» مجله مهندسی برق دانشگاه تبریز، جلد 47، شماره 1، صفحات 299-304، 1396.
[3]      A. C. Seabaugh and Q. Zhang, “Low-Voltage Tunnel Transistors for Beyond CMOS Logic,” Proc. IEEE, vol. 98, no. 12, pp. 2095–2110, 2010.
[4]      A. M. Ionescu and H. Riel, “Tunneling Field-Effect Transistors as Energy-Efficient Electronic Switches,” Nature, vol. 479, pp. 329–337, 2011.
[5]      S. Saurabh and M. J. Kumar, “Estimation and Compensation of Process Induced Variations in Nanoscale Tunnel Field Effect Transistors (TFETs) for Improved Reliability,” IEEE Trans. on Device and Materials Reliability, vol. 10, pp. 390–395, 2010.
[6]      M. J. Kumar and S. Janardhanan, “Doping-less Tunnel Field Effect Transistor: Design and Investigation,” IEEE Trans. Electron Devices, vol. 60, pp. 3285–3290, 2013.
[7]      M. S. Ram and D. B. Abdi, “Single Grain Boundary Tunnel Field Effect Transistors on Recrystallized Polycrystalline Silicon: Proposal and Investigation,” IEEE Electron Device Letters, vol. 35, no. 10, pp. 989–992, 2014.
[8]      A. Chaudhry and M. J. Kumar, “Controlling Short-Channel Effects in Deep Submicron SOI MOSFETs for Improved Reliability: A Review,” IEEE Trans. on Device and Materials Reliability, vol. 4, pp. 569–574, 2004.
[9]      A. H. Bayani, D. Dideban, M. Vali and N. Moezi “Germanene nanoribbon tunneling field effect transistor (GeNR-TFET) with a 10 nm channel length: analog performance, doping and temperature effects,” Semiconductor Science and Technology, vol. 31, no. 4, 2016.
[10]      D. B. Abdi and M. J. Kumar, “Controlling ambipolar current in tunneling FETs using overlapping Gate-on-Drain,” Journal of Electron Devices Society, vol. 2, no. 6, 2014.
[11]      H. J. Monkhorst and J. D. Pack, “Special points for Brillouin-zone integrations,” Phys. Rev. B, vol. 13, pp. 5188, 1976.
[12]      A. A. Mostofi, J. R. Yates, Y. Lee, I. Souza, D. Vanderbilt and N. Marzari, “wannier90: A tool for obtaining maximally-localized Wannier functions,” Computer Physics Communications, vol. 178, no. 9, pp. 685-699, 2008.
[13]      J. P. Perdew, K. Burke and Y. Wang. “Generalized gradient approximation for the exchange-correlation hole of a many electron system,” Phys. Rev. B, vol. 54, pp. 16533–9, 1996.
[14]      J. P. Perdew, J. A. Chevary, S. H. Vosko, K. A. Jackson, M. R. Pederson, D. J. Singh and C. Fiolhais. “Atoms, molecules, solids, and surfaces: applications of the generalized gradient approximation for exchange and correlation,” Phys. Rev. B, vol. 46, pp. 6671–87, 1992.
[15]      E. Gnani, A. Gnudi, S. Reggiani and G. Baccarani, “Drain-Conductance Optimization in Nanowire TFETs by Means of a Physics-Based Analytical Model,” Solid State Electronics, vol. 84, pp. 96–102, 2013.
[16]      S. M. Sze and Kwok K. NG, Physics of semiconductor devices, 3rd edition. John Wiley & Sons; 2006.
A. Shaker, M. E. Sabbagh and M. M. El-Banna, “Influence of Drain Doping Engineering on the Ambiploar conduction and High-Frequency Performance of TFETs,” IEEE Trans. Electron Device, vol. 64, no. 9, pp. 3541-3547, 2017