Article

Trap-assisted tunneling in high permittivity gate dielectric stacks

Department of Physics, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, B-3001 Leuven, BelgiumIMEC, Kapeldreef 75, B-3001 Leuven, Belgium
Journal of Applied Physics (impact factor: 2.17). 07/2000; DOI:10.1063/1.373587 pp.8615 - 8620
Source: IEEE Xplore

ABSTRACT The electrical characteristics of SiO x/ ZrO 2 and SiO x/ Ta 2 O 5 gate dielectric stacks are investigated. The current–density JG in these dielectric stacks is shown to be strongly temperature dependent at low voltage (below about 2 V), the more so in the ZrO 2 stack. On the other hand, JG is much less temperature dependent at higher voltage. These results are consistent with a model which takes into account the direct tunneling of electrons across the SiO x layer and the trap-assisted tunneling of electrons through traps with energy levels below the conduction band of the high permittivity dielectric layer. The energy levels and densities of these electron trapping centers are estimated by fitting this trap-assisted tunneling model to the experimental results. © 2000 American Institute of Physics.

0 0
 · 
0 Bookmarks
 · 
26 Views
  • Source
    Article: Total Dose and Bias Temperature Stress Effects for HfSiON on Si MOS Capacitors
    D.K. Chen, F.E. Mamouni, X.J. Zhou, R.D. Schrimpf, D.M. Fleetwood, K.F. Galloway, S. Lee, H. Seo, G. Lucovsky, B. Jun, J.D. Cressler
    [show abstract] [hide abstract]
    ABSTRACT: We have performed an experimental study of the effects of ionizing radiation and bias-temperature stress on Si MOS devices with HfSiON gate dielectrics. We compare the responses of homogeneous high-SiN films and low-SiN films that contain crystalline HfO. We observe that the low-SiN films are more sensitive to ionizing radiation than the high-SiN films. In particular, the low-SiN film that includes crystalline HfO is especially vulnerable to electron trapping due to substrate injection under positive irradiation bias. Both film types exhibit reduced radiation-induced charge trapping relative to previous Hf silicates. The high-SiN film exhibits less radiation-induced net oxide-trap charge density than earlier Hf silicate films processed without nitride. We also find that these devices are relatively robust against bias-temperature stress instabilities. Consistent with the radiation response, the low-SiN devices also display elevated levels of charge trapping relative to the high-SiN devices during bias-temperature stress.
    IEEE Transactions on Nuclear Science 01/2008; · 1.45 Impact Factor
  • Source
    Article: Band alignment and enhanced breakdown field of simultaneously oxidized and nitrided Zr film on Si.
    Yew Hoong Wong, Kuan Yew Cheong
    [show abstract] [hide abstract]
    ABSTRACT: ABSTRACT: The band alignment of ZrO2/interfacial layer/Si structure fabricated by simultaneous oxidation and nitridation of sputtered Zr on Si in N2O at 700°C for different durations has been established by using X-ray photoelectron spectroscopy. Valence band offset of ZrO2/Si was found to be 4.75 eV, while the highest corresponding conduction offset of ZrO2/interfacial layer was found to be 3.40 eV; owing to the combination of relatively larger bandgaps, it enhanced electrical breakdown field to 13.6 MV/cm at 10-6 A/cm2.
    Nanoscale Research Letters 08/2011; 6:489. · 2.73 Impact Factor
  • Source
    Article: Capacitance–voltage analysis of a high-k dielectric on silicon
    Davinder Rathee, Sandeep K Arya, Mukesh Kumar
    [show abstract] [hide abstract]
    ABSTRACT: Device characteristics of TiO 2 gate dielectrics deposited by a sol–gel method and DC sputtering method on a P-type silicon wafer are reported. Metal–oxide–semiconductor capacitors with Al as the top electrode were fabricated to study the electrical properties of TiO 2 films. The films were physically characterized by using X-ray diffraction, a capacitor voltage measurement, scanning electron microscopy, and by spectroscopy ellipsometry. The XRD and DST-TG indicate the presence of an anatase TiO 2 phase in the film. Films deposited at higher temperatures showed better crystallinity. The dielectric constant calculated using the capacitance voltage measurement was found to be 18 and 73 for sputtering and sol–gel samples respectively. The refractive indices of the films were found to be 2.16 for sputtering and 2.42 for sol–gel samples.
    journal of Semiconductor. 03/2012; 33(2):022001-1-4.

Show more

Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

conduction band
 
densities
 
dielectric stacks
 
direct tunneling
 
electrical characteristics
 
electron trapping centers
 
electrons
 
experimental results
 
higher voltage
 
permittivity dielectric layer
 
SiO <sub>x</sub> layer
 
trap-assisted tunneling
 
trap-assisted tunneling model