Schottky Barrier and Electronic States at Silicide-Silicon Interfaces

1985 ◽  
Vol 54 ◽  
Author(s):  
P. E. Schmid ◽  
M. Liehr ◽  
F. K. Legoues ◽  
P. S. Ho
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Interface States ◽  
Impurity Incorporation ◽  
Defect States ◽  
Fermi Level Pinning ◽  
Barrier Heights ◽  
Interfacial Defect ◽  
Consistent Picture ◽  
Chemical Correlation

ABSTRACTThis paper reviews the recent studies on Schottky barrier and interface states at silicide-silicon interfaces, with emphasis placed on the results obtained from the epitaxial Ni suicides. A model based on interfacial defect states has been proposed to account for the overall chemical correlation between the barrier height and the metal electronegativity. Measurements on the barrier heights of type A, B and C epitaxial Ni suicides show that these three interfaces can be formed with high degrees of perfection to yield a barrier of 0.78 eV. Similar interfaces formed under less ideal conditions or with impurity incorporation decrease the barrier to 0.66 eV. The density and distribution of the interface states measured by a capacitance spectroscopy method correlate well with the structural perfection of the single and mixed-phase interfaces. A consistent picture seems to have emerged suggesting that the barrier height at silicide-Si interfaces is formed as a result of Fermi level pinning by interfacial defect states which are controlled primarily by the degree of perfection of the interface instead of the specific epitaxy.

Increase in Schottky Barrier Height in the CoSi2/Si (100) Interface Caused by Hydrogen

1992 ◽  
Vol 281 ◽  
Author(s):  
A. D. Marwick ◽  
M. O. Aboelfotoh ◽  
R. Casparis
Keyword(s):  
Fermi Level ◽  
Schottky Barrier ◽  
Barrier Height ◽  
Schottky Barrier Height ◽  
Interface States ◽  
Hydrogen Atoms ◽  
Fermi Level Pinning ◽  
Gap States

ABSTRACTIt is shown that the presence of 8 × 1015 hydrogen atoms/cm2 in the CoSi2/Si (100) interface causes an increase in the Schottky barrier height of 120 meV, and that passivation of dopants in the substrate is not the cause of this change. The data is evidence that the position of the Fermi level in this interface is controlled by defect-related interface states. After hydrogenation the Schottky barrier height agrees with that predicted by theory for Fermi level pinning by virtual gap states of the silicon.

Electrical Properties and Schottky Barriers of Metal-Semiconductor Interfaces

1990 ◽  
Vol 181 ◽  
Author(s):  
M.O. Aboelfotoh
Keyword(s):  
Electrical Properties ◽  
Temperature Dependence ◽  
Schottky Barrier ◽  
Barrier Height ◽  
Fermi Level Pinning ◽  
Barrier Heights ◽  
Semiconductor Interfaces ◽  
Barrier Formation ◽  
Indirect Band Gap ◽  
P Type

ABSTRACTThe electrical properties of metal/Si(100) and metal/Ge(100) interfaces formed by the deposition of metal on both n-type and p-type Si(100) and Ge(100) have been studied in the temperature range 77-295 K with the use of current- and capacitance-voltage techniques. Compound formation is found to have very little or no effect on the Schottky-barrier height and its temperature dependence. For silicon, the barrier height and its temperature dependence are found to be affected by the metal. For germanium, on the other hand, the barrier height and its temperature dependence are unaffected by the metal. The temperature dependence of the Si and Ge barrier heights is found to deviate from the predictions of recent models of Schottky-barrier formation based on the suggestion of Fermi-level pinning in the center of the semiconductor indirect band gap.

scholarly journals Reduction of Schottky Barrier Height at Graphene/Germanium Interface with Surface Passivation

2019 ◽  
Vol 9 (23) ◽  
pp. 5014
Author(s):  
Courtin ◽  
Moréac ◽  
Delhaye ◽  
Lépine ◽  
Tricot ◽  
...  
Keyword(s):  
Fermi Level ◽  
Schottky Barrier ◽  
Barrier Height ◽  
Schottky Barrier Height ◽  
Surface Passivation ◽  
2D Materials ◽  
Semiconductor Interface ◽  
Weakly Interact ◽  
Fermi Level Pinning ◽  
Semiconductor Interfaces

Fermi level pinning at metal/semiconductor interfaces forbids a total control over the Schottky barrier height. 2D materials may be an interesting route to circumvent this problem. As they weakly interact with their substrate through Van der Waals forces, deposition of 2D materials avoids the formation of the large density of state at the semiconductor interface often responsible for Fermi level pinning. Here, we demonstrate the possibility to alleviate Fermi-level pinning and reduce the Schottky barrier height by the association of surface passivation of germanium with the deposition of 2D graphene.

Fermi-level pinning and Schottky barrier heights on epitaxially grown fully strained and partially relaxed n-type Si1−xGex layers

1999 ◽  
Vol 86 (12) ◽  
pp. 6890-6894 ◽  
Author(s):  
M. Mamor ◽  
O. Nur ◽  
M. Karlsteen ◽  
M. Willander ◽  
F. D. Auret
Keyword(s):  
Fermi Level ◽  
Schottky Barrier ◽  
Fermi Level Pinning ◽  
Barrier Heights

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

2008 ◽  
Vol 22 (14) ◽  
pp. 2309-2319 ◽  
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.

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

2012 ◽  
Vol 90 (1) ◽  
pp. 73-81 ◽  
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.

The influence of Fermi level pinning/depinning on the Schottky barrier height and contact resistance in Ge/CoFeB and Ge/MgO/CoFeB structures

2010 ◽  
Vol 96 (5) ◽  
pp. 052514 ◽  
Author(s):  
Donkoun Lee ◽  
Shyam Raghunathan ◽  
Robert J. Wilson ◽  
Dmitri E. Nikonov ◽  
Krishna Saraswat ◽  
...  
Keyword(s):  
Contact Resistance ◽  
Fermi Level ◽  
Schottky Barrier ◽  
Barrier Height ◽  
Schottky Barrier Height ◽  
Fermi Level Pinning

Interface States and Barrier Heights on Metal/4H-SiC Interfaces

2009 ◽  
Vol 615-617 ◽  
pp. 427-430 ◽  
Author(s):  
Shaweta Khanna ◽  
Arti Noor ◽  
Man Singh Tyagi ◽  
Sonnathi Neeleshwar
Keyword(s):  
Work Function ◽  
Barrier Height ◽  
Surface Preparation ◽  
Interface States ◽  
Careful Examination ◽  
Barrier Heights ◽  
Metal Work Function ◽  
Wide Range ◽  
Metal Work ◽  
Density Of Interface States

Available data on Schottky barrier heights on silicon and carbon rich faces of 4H-SiC have been carefully analyzed to investigate the mechanism of barrier formation on these surfaces. As in case of 3C and 6H-SiC, the barrier heights depend strongly upon method of surface preparation with a considerable scatter in the barrier height for a given metal-semiconductor system. However, for each metal the barrier height depends on the metal work function and strong pinning of the Fermi level has not been observed. The slopes of the linear relation between the barrier heights and metal work functions varies over a wide range from 0.2 to about 0.75 indicating that the density of interface states depends strongly on the method of surface preparation. By a careful examination of the data on barrier heights we could identify a set of nearly ideal interfaces in which the barrier heights vary linearly with metal work function approaching almost to the Schottky limit. The density of interface states for these interfaces is estimated to lie between 4.671012 to 2.631012 states/ cm2 eV on the silicon rich surface and about three times higher on the carbon rich faces. We also observed that on these ideal interfaces the density of interface states was almost independent of metal indicating that the metal induced gap states (MIGS) play no role in determining the barrier heights in metal-4H-SiC Schottky barriers.

Delineation of Defects Reducing Schottky Barrier Heights on 4H-SiC by the Electrochemical Deposition

2008 ◽  
Vol 600-603 ◽  
pp. 373-376
Author(s):  
Masashi Kato ◽  
Kazuya Ogawa ◽  
Masaya Ichimura
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Electrochemical Deposition ◽  
Schottky Barrier Height ◽  
Proper Time ◽  
Etch Pits ◽  
Barrier Heights ◽  
Etch Pit ◽  
Deposition Voltage ◽  
Deposited Films

We identified regions with low Schottky barrier height on 4H-SiC surfaces by the electrochemical deposition of ZnO. When we adopt an appropriate deposition voltage, ZnO grew preferentially at the regions with the low Schottky barrier height. Thus, we were able to identify the ZnO film only at these regions if we stopped the deposition at a proper time. We compared positions of the deposited film and etch pit after molten NaOH etching. As a result, in a bulk 4H-SiC, the films were deposited around some of micropipe positions. On the other hand, in an epitaxial 4H-SiC layer, although approximately a half of deposited films seemed to grow at the etch-pit defect positions, other deposited films were grown at positions without etch-pit defects. Therefore the Schottky barrier heights were reduced by not only defects emerging as etch pits but also other kind of origins in epitaxial 4H-SiC.

Sign in / Sign up

Export Citation Format

Share Document