THE CURRENT–VOLTAGE CHARACTERISTICS OF THE Au/MBEn-GaAs SCHOTTKY DIODES IN A WIDE TEMPERATURE RANGE

2013 ◽  
Vol 27 (19) ◽  
pp. 1350088 ◽  
Author(s):  
HASAN EFEOǦLU ◽  
ABDULMECIT TURUT

The Au/MBE n- GaAs Schottky diodes have been fabricated by us. The slope of the conventional ln (I0/T2) versus (kT)-1 plotted in the temperature range of 120–350 K has given a Richardson constant (RC) of 7.69 A (cmK)-2 which is in close agreement with the value of 8.16 A/cm2 K 2 known for n-type GaAs . The barrier height (BH) value in 40–160 K range has decreased obeying to Gaussian distribution (GD) model of the BH based on thermionic emission current theory. The modified RC plot according to the GD model has given a RC value of 2.45 A (cmK)-2 or a value of 2.38 A (cmK)-2 by taking into account the temperature dependence of the standard deviation. Therefore, we have modified the Richardson's plot using the temperature dependent values of the effective area of the patches introduced by lateral inhomogeneity of the BHs and we have obtained a RC value of 8.10 A (cmK)-2.

1993 ◽  
Vol 325 ◽  
Author(s):  
Z.C. Huang ◽  
C.R. Wie

AbstractDeep levels have been measured in molecular beam epitaxy grown Ga0.51In0.49P/GaAs heterostructure by double correlation deep level transient spectroscopy. Gold(Au) and Aluminum (Al) metals were used for Schottky contact. A contact-related hole trap with an activation energy of 0.50-0.75eV was observed at the A1/GaInP interface, but not at the Au/GaInP interface. To our knowledge, this contact-related trap has not been reported before. We attribute this trap to the oxygen contamination, or a vacancy-related defect, VIn or VGa. A new electron trap at 0.28eV was also observed in both Au- and Al-Schottky diodes. Its depth profile showed that it is a bulk trap in GaInP epilayer. The temperature dependent current-voltage characteristics (I-V-T) show a large interface recombination current at the GaInP surface due to the Al-contact. Concentration of the interface trap and the magnitude of recombination current are both reduced by a rapid thermal annealing at/or above 450°C after the aluminum deposition.


2012 ◽  
Vol 711 ◽  
pp. 188-192
Author(s):  
Muhammad Yousuf Zaman ◽  
Denis Perrone ◽  
Sergio Ferrero ◽  
Luciano Scaltrito ◽  
Marco Naretto

Forward current-voltage characteristics of a medium sized (3.05mm2)Mo/4H-SiC (molyb-denum on silicon carbide) Schottky diode|fabricated for high power applications | are analysedwithin a temperature range of 125-450 K. Accurate theoretical modeling is carried out using Tung'smodel in which it is considered that numerous low barrier nanometer size patches, present in uniformhigh barrier, are responsible for the inhomogeneities in the Schottky barrier of SiC-based electronicdevices. A significant difference is observed between the effective area involved in the current trans-port and the geometric area of the Schottky contact along with a dependence of the ideality factor andhe barrier height on temperature. The obtained values of uniform Schottky barrier and Richardson'sconstant are seen to be in accordance with previous works. It is concluded that the above mentionedmodel can be used to describe the electrical behaviour of Mo/4H-SiC Schottky diodes.


2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
P. Pipinys ◽  
V. Lapeika

Temperature-dependent reverse-bias current-voltage characteristics obtained by other researchers for Schottky diodes fabricated on GaN are reinterpreted in terms of phonon-assisted tunneling (PhAT) model. Temperature dependence of reverse-bias leakage current is shown could be caused by the temperature dependence of electron tunneling rate from traps in the metal-semiconductor interface to the conduction band of semiconductor. A good fit of experimental data with the theory is received in a wide temperature range (from 80 K to 500 K) using for calculation the effective mass of 0.222 . and for the phonon energy the value of 70 meV. The temperature and bias voltages dependences of an apparent barrier height (activation energy) are also explicable in the framework of the PhAT model.


2012 ◽  
Vol 711 ◽  
pp. 174-178 ◽  
Author(s):  
Muhammad Yousuf Zaman ◽  
Denis Perrone ◽  
Sergio Ferrero ◽  
Luciano Scaltrito ◽  
Marco Naretto

Various attempts have been made to evaluate the correct value (A*=146 A/cm2.K2) ofRichardson's constant. In 2005 S. Ferrero et al. published their research in which they performedan analysis of electrical characterizations of twenty Ti/4H-SiC(titanium on silicon carbide) Schottkydiodes with the help of thermionic emission theory and evaluated the value of Richardson's constantto be 17±8 A/cm2.K2; which is very low as compared to the theoretical value of 146 A/cm2.K2.Wehave tried in this paper to evaluate the Richardson's constant's value by nearly same experimental tech-niques followed by S. Ferrero et al. and additionally, have applied Tung's theoretical approach whichdeals with the incorrect value of A* in the perspective of Schottky barrier inhomogeneities caused bythe presence of nanometer size low barrier patches present in the uniform high barrier of the Schottkydiode.We have fabricated two Ti/4H-SiC (titanium on silicon carbide) Schottky diodes with differentareas and oneMo/4H-SiC (molybdenumon silicon carbide) Schottky diode. In this paper we have pre-sented a comparative analysis of forward current-voltage characteristics of all three Schottky diodes.In all three cases we were successful in the evaluation of nearly correct value of Richardson's constant.This work emphasizes the effects of differentmetal-SiC combinations and laboratory environments onthe evaluation of Richardson's constant and the effective area involved in the current transport. As pre-dicted by Tung's model the effective area is seen to be substantially different from the geometric areaof the Schottky diode. Evaluated values of A*, with an error of ±2, come out to be 145.39, 148.33and 148.33 A/cm2.K2for Ti/4H-SiC(large area), Mo/4H-SiC and Ti/4H-SiC(small area) Schottkydiodes, respectively.


2013 ◽  
Vol 313-314 ◽  
pp. 270-274
Author(s):  
M. Faisal ◽  
M. Asghar ◽  
Khalid Mahmood ◽  
Magnus Willander ◽  
O. Nur ◽  
...  

Temperature dependent current-voltage (I-V) and capacitance-voltage (C-V) measurements were utilized to understand the transport mechanism of Pd Schottky diodes fabricated on Zn- and O-faces of ZnO. From I-V measurements, in accordance with the thermionic emission mechanism theory, it was found that the series resistance Rsand the ideality factor n were strongly temperature dependent that decreased with increasing temperature for both the faces (Zn and O-face) of ZnO revealing that the thermionic emission is not the dominant process. The barrier height øB(I-V)increased with increasing temperature for both faces. The measured values of ideality factor, barrier height and series resistance for Zn- and O-faces at room temperature were 4.4, 0.60 eV, 217 Ω and 2.8, 0.49 eV, 251 Ω respectively. The capacitance-voltage (C–V) measurements were used to determine the doping concentration Nd, the built-in-potential Vbi, and the barrier height øB(C-V). The doping concentration was found to be decreased with increasing depth. The barrier height øB(C-V)calculated for O-polar and Zn-polar faces decreases with increasing temperature. The values of barrier height øB(C-V)determined from C-V measurements were found higher than the values of barrier height øB(I-V). Keeping in view the calculated values of ideality factor, barrier height, and series resistance shows that O-polar face is qualitatively better than Zn-polar face.


2012 ◽  
Vol 209 (8) ◽  
pp. 1575-1578 ◽  
Author(s):  
Basanta Roul ◽  
Thirumaleshwara N. Bhat ◽  
Mahesh Kumar ◽  
Mohana K. Rajpalke ◽  
A. T. Kalghatgi ◽  
...  

2013 ◽  
Vol 858 ◽  
pp. 171-176
Author(s):  
Nathaporn Promros ◽  
Ryūhei Iwasaki ◽  
Suguru Funasaki ◽  
Kyohei Yamashita ◽  
Chen Li ◽  
...  

n-Type NC-FeSi2/p-type Si heterojunctions were successfully fabricated by PLD, and their forward current-voltage characteristics were analyzed on the basis of thermionic emission theory (TE) in the temperature range from 300 down to 77 K. With a decrease in the temperature, the ideality factor was increased while the zero-bias barrier height was decreased. The calculated values of ideality factor and barrier height were 3.07 and 0.63 eV at 300 K and 10.75 and 0.23 eV at 77 K. The large value of ideality factor indicated that a tunneling process contributes to the carrier transport mechanisms in the NC-FeSi2 films. The series resistance, which was estimated by Cheungs method, was strongly dependent on temperature. At 300 K, the value of series resistance was 12.44 Ω and it was dramatically enhanced to be 1.71× 105 Ω at 77 K.


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