Temperature dependence of current-and capacitance-voltage characteristics of an Au/4H-SiC Schottky diode


Gulnahar M.

SUPERLATTICES AND MICROSTRUCTURES, cilt.76, ss.394-412, 2014 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 76
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1016/j.spmi.2014.09.035
  • Dergi Adı: SUPERLATTICES AND MICROSTRUCTURES
  • Sayfa Sayıları: ss.394-412

Özet

In this study, the current-voltage (I-V) and capacitance-voltage (C-V) measurements of an Au/4H-SiC Schottky diode are characterized as a function of the temperature in 50-300 K temperature range. The experimental parameters such as ideality factor and apparent barrier height presents to be strongly temperature dependent, that is, the ideality factor increases and the apparent barrier height decreases with decreasing temperature, whereas the barrier height values increase with the temperature for C-V data. Likewise, the Richardson plot deviates at low temperatures. These anomaly behaviors observed for Au/4H-SiC are attributed to Schottky barrier inhomogeneities. The barrier anomaly which relates to interface of Au/4H-SiC is also confirmed by the C-V measurements versus the frequency measured in 300 K and it is interpreted by both Tung's lateral inhomogeneity model and multi-Gaussian distribution approach. The values of the weighting coefficients, standard deviations and mean barrier height are calculated for each distribution region of Au/4H-SiC using the multi-Gaussian distribution approach. In addition, the total effective area of the patches NA(e) is obtained at separate temperatures and as a result, it is expressed that the low barrier regions influence meaningfully to the current transport at the junction. The homogeneous barrier height value is calculated from the correlation between the ideality factor and barrier height and it is noted that the values of standard deviation from ideality factor versus q/3kT curve are inclose agreement with the values obtained from the barrier height versus q/2kT variation. As a result, it can be concluded that the temperature dependent electrical characteristics of Au/4H-SiC can be successfully commented on the basis of the thermionic emission theory with both models. (C) 2014 Elsevier Ltd. All rights reserved.

In this study, the current–voltage (I–V) and capacitance–voltage
(C–V) measurements of an Au/4H-SiC Schottky diode are characterized
as a function of the temperature in 50–300 K temperature
range. The experimental parameters such as ideality factor and
apparent barrier height presents to be strongly temperature
dependent, that is, the ideality factor increases and the apparent
barrier height decreases with decreasing temperature, whereas
the barrier height values increase with the temperature for C–V
data. Likewise, the Richardson plot deviates at low temperatures.
These anomaly behaviors observed for Au/4H-SiC are attributed
to Schottky barrier inhomogeneities. The barrier anomaly which
relates to interface of Au/4H-SiC is also confirmed by the C–V
measurements versus the frequency measured in 300 K and it is
interpreted by both Tung’s lateral inhomogeneity model and
multi-Gaussian distribution approach. The values of the weighting
coefficients, standard deviations and mean barrier height are calculated
for each distribution region of Au/4H-SiC using the multi-
Gaussian distribution approach. In addition, the total effective area
of the patches NAe is obtained at separate temperatures and as a
result, it is expressed that the low barrier regions influence meaningfully
to the current transport at the junction. The homogeneous
barrier height value is calculated from the correlation between the
ideality factor and barrier height and it is noted that the values of
standard deviation from ideality factor versus q/3kT curve are in
close agreement with the values obtained from the barrier height
versus q/2kT variation. As a result, it can be concluded that the
temperature dependent electrical characteristics of Au/4H-SiC
can be successfully commented on the basis of the thermionic
emission theory with both models.