Comparative Study of Temperature Dependent Barrier Heights of Pd/ZnO Schottky Diodes Grown along Zn- and O-Faces

In this study, the effect of polar face on Schottky barrier diodes has been investigated. Two samples of ZnO were grown hydrothermally under similar growth conditions. The Palladium (Pd) metal contacts of area 0.78 mm2were fabricated on both faces and were studied comprehensively using DLS-83 Deep Level Spectrometer over temperature range of 160K330K. The current-voltage (IV) measurements revealed that the ideality factor n and barrier height ϕBwere strongly temperature dependent for both faces (Zn and O-face) of ZnO, indicating that the thermionic emission is not the dominant process, which showed the inhomogenity in the barrier heights of grown samples. This barrier height inhomogenity was explained by applying Gaussian distribution model. The extrapolation of the linear ϕapverses n plot to n = 1 has given a homogeneous barrier height of approximately 0.88±0.01 eV and 0.76±0.01 eV for Zn and O-faces respectively. ϕapversus 1/T plot was drawn to obtain the values of mean barrier height for Zn and O-face (0.88±0.01 eV, 0.76±0.01 eV) and standard deviation (δs) (0.015±0.001 V, 0.014±0.001 V) at zero bais respectively. The value of δsfor the Zn-face is larger than O-face, showing that inhomogenity in the barrier heights is more in the sample grown along Zn-face as compared to the sample grown along O-face.

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Evaluation of On-State Resistance and Boron-Related Levels in n-Type 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.483-485.425 ◽

2005 ◽

Vol 483-485 ◽

pp. 425-428 ◽

Cited By ~ 2

Author(s):

R.R Ciechonski ◽

Samuele Porro ◽

Mikael Syväjärvi ◽

Rositza Yakimova

Keyword(s):

Minority Carrier ◽

Deep Level ◽

Schottky Diodes ◽

Depth Profiling ◽

Thermionic Emission ◽

Barrier Heights ◽

Transient Spectroscopy ◽

State Resistance ◽

Thick Layers

Specific on-resistance Ron estimated from current density-voltage characteristics of Schottky diodes on thick layers exhibits variations from tens of mW.cm2 to tens of W.cm2 for different doping levels. In order to understand the occurrence of high on-state resistance, Schottky barrier heights were first estimated for both forward and reverse bias with the application of thermionic emission theory and were in agreement with a literature reported values. Decrease in mobility with the temperature was observed and its dependencies of T–1.3 and T–2.0 for moderately doped and low doped samples respectively were estimated. From deep level measurements by Minority Carrier Transient Spectroscopy, an influence of shallow boron related levels and D-center on dependence of on-state resistance was observed, being more pronounced in low doped samples. Similar tendency was observed in depth profiling of Ron. This suggests a major role of boron in a compensation mechanism thus resulting in high Ron.

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Analysis of temperature-dependent Schottky barrier parameters of Cu–Au Schottky contacts to n-InP

Canadian Journal of Physics ◽

10.1139/p11-142 ◽

2012 ◽

Vol 90 (1) ◽

pp. 73-81 ◽

Cited By ~ 1

Author(s):

V. Lakshmi Devi ◽

I. Jyothi ◽

V. Rajagopal Reddy

Keyword(s):

Schottky Barrier ◽

Barrier Height ◽

Gaussian Distribution ◽

Ideality Factor ◽

Thermionic Emission ◽

Schottky Contacts ◽

Temperature Dependent ◽

Semiconductor Interface ◽

Zero Bias ◽

Barrier Heights

In this work, we have investigated the electrical characteristics of Au–Cu–n-InP Schottky contacts by current–voltage (I–V) and capacitance–voltage (C–V) measurements in the temperature range 260–420 K in steps of 20 K. The diode parameters, such as the ideality factor, n, and zero-bias barrier height, Φb0, have been found to be strongly temperature dependent. It has been found that the zero-bias barrier height, Φb0(I–V), increases and the ideality factor, n, decreases with an increase in temperature. The forward I–V characteristics are analyzed on the basis of standard thermionic emission (TE) theory and the assumption of gaussian distribution of barrier heights, due to barrier inhomogeneities that prevail at the metal–semiconductor interface. The zero-bias barrier height Φb0 versus 1/2kT plot has been drawn to obtain the evidence of a gaussian distribution of the barrier heights. The corresponding values are Φb0 = 1.16 eV and σ0 = 159 meV for the mean barrier height and standard deviation, respectively. The modified Richardson plot has given mean barrier height, Φb0, and Richardson constant, A**, as 1.15 eV and 7.34 Acm−2K−2, respectively, which is close to the theoretical value of 9.4 Acm−2K−2. Barrier heights obtained from C–V measurements are higher than those obtained from I–V measurements. This inconsistency between Schottky barrier heights (SBHs) obtained from I–V and C–V measurements was also interpreted. The temperature dependence of the I–V characteristics of the Au–Cu–n-InP Schottky diode has been explained on the basis of TE mechanism with gaussian distribution of the SBHs.

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A New Approach to Temperature Dependent Ideality Factors in Schottky Contacts

MRS Proceedings ◽

10.1557/proc-260-359 ◽

1992 ◽

Vol 260 ◽

Cited By ~ 13

Author(s):

Zs. J. Horváth

Keyword(s):

Experimental Data ◽

Low Temperatures ◽

Schottky Diodes ◽

Thermionic Emission ◽

Schottky Contacts ◽

Temperature Dependent ◽

Model Calculations ◽

New Approach ◽

Barrier Heights ◽

Thermionic Field Emission

ABSTRACTSchottky diodes often exhibit anomalous current-vol tage characteristics at low temperatures (T) with T dependent ideality factors (IF) and apparent barrier heights (BH) evaluated for the thermionic emission. In this paper theoretical expressions are first presented for the T dependences of the IF and the apparent BH for the thermionic-field emission (TFE) including the bias dependence of BH. Model calculations are reported, which has been performed using these expressions, and their results are compared with the available experimental data. It is shown that the T dependence of the 1 Fs and apparent BHs often may be explained self consistently by the TFE with anomalously high characteristic energies Eoo.

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Current-Voltage and Capacitance-Voltage Characteristics of Pd Schottky Diodes Fabricated on ZnO Grown along Zn- and O-Faces

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.313-314.270 ◽

2013 ◽

Vol 313-314 ◽

pp. 270-274

Author(s):

M. Faisal ◽

M. Asghar ◽

Khalid Mahmood ◽

Magnus Willander ◽

O. Nur ◽

...

Keyword(s):

Barrier Height ◽

Ideality Factor ◽

Doping Concentration ◽

Series Resistance ◽

Schottky Diodes ◽

Thermionic Emission ◽

Temperature Dependent ◽

Current Voltage ◽

Capacitance Voltage ◽

Increasing Temperature

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.

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Measure and analysis of 4H-SiC Schottky barrier height with Mo contacts

The European Physical Journal Applied Physics ◽

10.1051/epjap/2018180282 ◽

2019 ◽

Vol 85 (1) ◽

pp. 10102 ◽

Cited By ~ 9

Author(s):

Teng Zhang ◽

Christophe Raynaud ◽

Dominique Planson

Keyword(s):

Barrier Height ◽

Deep Level ◽

Schottky Contact ◽

Thermionic Emission ◽

Distribution Model ◽

Emission Model ◽

Height Distribution ◽

Current Voltage ◽

Transient Spectroscopy ◽

Fluctuation Model

Current–voltage (I–V) and capacitance–voltage (C–V) characteristics of Schottky Mo/4H-SiC diodes have been measured and analyzed as a function of temperature between 80 and 400 K. The I–V characteristics significantly deviate from ideal characteristics predicted by the thermionic emission model because of the inhomogeneity of Schottky contact. After a brief review of the different existing models, the main parameters (ideality factor, barrier height, and effective Richardson constant) of both diodes have been extracted in the frame of a Gaussian barrier height distribution model, whose mean and standard deviation are linearly dependent on voltage and temperature, as well as in the context of the potential fluctuation model. The results are compared with the values extracted by C–V and the values in the literature. A link is established between these two models. Diodes of different I–V characteristics, either identified as single barrier or double barrier, have been analyzed by Deep Level Transient Spectroscopy (DLTS) to investigate the deep level defects present. No noticeable difference has been found.

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Temperature-Dependent Electrical Characteristics of Ag Schottky Contacts to Differently Grown O-Polar Bulk ZnO

Journal of Electronic Packaging ◽

10.1115/1.4023404 ◽

2013 ◽

Vol 135 (1) ◽

Cited By ~ 3

Author(s):

Hogyoung Kim ◽

Ahrum Sohn ◽

Yunae Cho ◽

Dong-Wook Kim

Keyword(s):

Electron Transport ◽

Electrical Properties ◽

Schottky Contact ◽

Thermionic Emission ◽

Schottky Contacts ◽

Current Transport ◽

Electrical Characteristics ◽

Temperature Dependent ◽

Barrier Heights ◽

Two Samples

The temperature-dependent electrical properties of Ag Schottky contacts to differently grown O-polar bulk ZnO single crystals were comparatively investigated in the temperature range of 100–300 K. Schottky contact to hydrothermal ZnO produced the higher barrier heights (lower ideality factors) than that of pressurized melt-grown ZnO. The modified Richardson plots for two samples produced the larger Richardson constant compared to the theoretical value of 32 A cm−2 K−2 for n-type ZnO, indicating that the inhomogeneous barrier height with the thermionic emission (TE) model could not explain the current transport. The conductive accumulation layers on the ZnO surfaces might not be removed effectively for two samples, which degraded the rectifying characteristics. The different electron transport characteristics between hydrothermal and pressurized melt-grown ZnO could be explained by the different degree of Ag-O formation at the interface.

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The Effect of Sintering Temperature on the Barrier Height of p-type PtSi Schottky Diodes

Australian Journal of Physics ◽

10.1071/ph910067 ◽

1991 ◽

Vol 44 (1) ◽

pp. 67 ◽

Cited By ~ 4

Author(s):

Vincent WL Chin ◽

Stephen M Newbery ◽

John WV Storey ◽

Ulrich Theden

Keyword(s):

Barrier Height ◽

Sintering Temperature ◽

Schottky Diodes ◽

Consistent Difference ◽

Two Samples ◽

Different Temperatures ◽

P Type

The effect of sintering temperature on the barrier height of p-type PtSi Schottky diodes is studied by electrical and infrared photoresponse methods. It is revealed that there is a consistent difference of about 0�06 eV for two samples sintered at different temperatures.

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Investigation of temperature dependent barrier height of Au/ZnO/Si schottky diodes

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/60/1/012041 ◽

2014 ◽

Vol 60 ◽

pp. 012041 ◽

Cited By ~ 7

Author(s):

M Asghar ◽

K Mahmood ◽

S Rabia ◽

Samaa B M ◽

M Y Shahid ◽

...

Keyword(s):

Barrier Height ◽

Schottky Diodes ◽

Temperature Dependent

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TEMPERATURE DEPENDENCE OF ELECTRICAL CHARACTERISTICS OF Cr/p–Si(100) SCHOTTKY BARRIER DIODES

International Journal of Modern Physics B ◽

10.1142/s0217979208039496 ◽

2008 ◽

Vol 22 (14) ◽

pp. 2309-2319 ◽

Cited By ~ 1

Author(s):

K. ERTURK ◽

M. C. HACIISMAILOGLU ◽

Y. BEKTORE ◽

M. AHMETOGLU

Keyword(s):

Temperature Dependence ◽

Schottky Barrier ◽

Barrier Height ◽

Thermionic Emission ◽

Electrical Characteristics ◽

Schottky Barrier Diodes ◽

Semiconductor Interface ◽

Linear Portion ◽

Barrier Heights ◽

P Type

The electrical characteristics of Cr / p – Si (100) Schottky barrier diodes have been measured in the temperature range of 100–300 K. The I-V analysis based on thermionic emission (TE) theory has revealed an abnormal decrease of apparent barrier height and increase of ideality factor at low temperature. The conventional Richardson plot exhibits non-linearity below 200 K with the linear portion corresponding to activation energy 0.304 eV and Richardson constant (A*) value of 5.41×10-3 Acm-2 K -2 is determined from the intercept at the ordinate of this experimental plot, which is much lower than the known value of 32 Acm-2 K -2 for p-type Si . It is demonstrated that these anomalies result due to the barrier height inhomogeneities prevailing at the metal-semiconductor interface. Hence, it has been concluded that the temperature dependence of the I-V characteristics of the Cr/p – Si Schottky barrier diode can be successfully explained on the basis of TE mechanism with a Gaussian distribution of the barrier heights. Furthermore, the value of the Richardson constant found is much closer than that obtained without considering the inhomogeneous barrier heights.

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