A Theoretical Study on Electron Tunneling Current in Isotropic High-κ Dielectric Stack-Based MOS Capacitors with Charge Trapping

Abstract:

Electron tunneling current in an isotropic metal-oxide-semiconductor (MOS) capacitor with a high-κ dielectric stack has been studied by considering the effect of charge trapping. The transmittance was analytically calculated by employing an Airy-wavefunction approach and including a coupling term between the transverse and longitudinal kinetic energies which is represented by an electron phase velocity in the gate. The transmittance was then applied to obtain tunneling currents in isotropic n⁺poly-Si/HfSiO_xN/trap/SiO₂/Si (100) MOS capacitors for different electron gate phase velocities and trap depths and widths. The calculated results show that the transmittance and tunneling current increase as the electron gate velocity decreases. In addition, the increase in the trap depth and width enhances the tunneling current.

• Periodical: Advanced Materials Research (Volume 896)
• Pages: 363-366
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.896.363
• Online since: February 2014
• Authors: Fatimah A. Noor*, Khairiah Khairiah, Abdullah Mikrajuddin, Khairurrijal Khairurrijal
• Keywords: Airy-Wavefunction Approach, Charge Trapping, Electron Gate Velocity, Tunneling Current

References

[1] S. –H. Lo, D. A. Buchanan, Y. Taur, W. Wang, Quantum-mechanical modeling of electron tunneling current from the inversion layer of ultra-thin-oxide nMOSFET's, IEEE Electron Device Lett. 18 (1997) 209-211.

DOI: 10.1109/55.568766

[2] F. A. Noor, M. Abdullah, Sukirno, Khairurrijal, A. Ohta, S. Miyazaki, Electron and hole components of tunneling currents through an interfacial oxide-high-k gate stack in metal-oxide-semiconductor capacitors, J. Appl. Phys. 108 (2010).

DOI: 10.1063/1.3503457

[3] N. A. Chowdhury, D. Misra, Charge trapping at deep states in Hf–silicate based high-k gate dielectrics, J. Electrochem. Soc. 154 (2007) G30-G37.

DOI: 10.1149/1.2402989

[4] A. Aziz, K. Kassami, ka. Kassami, F. Olivie, Modelling of the influence of charges trapped in the oxide on the I(Vg) characteristics of metal-ultra-thin oxide-semiconductor structure Semicond. Sci. Technol. 19 (2004) 877-884.

DOI: 10.1088/0268-1242/19/7/017

[5] A. Bouazra, S. A. –B. Nasrallah, A. Poncet, M. Said, Current tunnelling through MOS devices, Mater. Sci. Eng. C 28 (2008) 662-665.

DOI: 10.1016/j.msec.2007.10.010

[6] F. A. Noor, M. F. Sahdan, P. Achmari, F. Iskandar, M. Abdullah, Khairurrijal, Electron tunnel current through HfO2/SiO2 nanometer thick layers with a trapped charge: effects of electron incident angle and silicon substrate orientation, AIP Conference Proceedings 1415, American Institute of Physics, Melville, NY, 2011, pp.32-35.

DOI: 10.1063/1.3667213

[7] F. A. Noor, F. Iskandar, M. Abdullah, Khairurrijal, Analysis of electron leakage current in MOS capacitors by using anisotropic and isotropic mass approaches, Electron. Lett. 48 (2012) 1585-1586.

DOI: 10.1049/el.2012.2343

[8] F. A. Noor, M. Abdullah, Sukirno, Khairurrijal., Comparison of electron transmittances and tunneling currents in ananisotropic TiNx/HfO2/SiO2/p-Si(100) metal–oxide–semiconductor (MOS) capacitor, J. Semicond. 31 (2010) 124002-1-124002-5.

DOI: 10.1088/1674-4926/31/12/124002

[9] L. F. Mao, The effects of the injection-channel velocity on the gate leakage current of nanoscale MOSFETs, IEEE Electron Devices Lett. 28 (2007) 161-163.

DOI: 10.1109/led.2006.889214

[10] D. Ahn, S. L. Chuang, Exact calculations of quasi-bound states of an isolated quantum well with uniform electric fields: quantum-well Stark resonance, Phys. Rev. B. 34 (1986) 9034- (1937).

DOI: 10.1103/physrevb.34.9034