Current–voltage characteristics of Schottky barriers with barrier heights larger than the semiconductor band gap: The case of NiGe∕n-(001)Ge contact

We have used depth-resolved cathodoluminescence spectroscopy (DRCLS) to correlate subsurface deep level emissions and double barrier current-voltage (I-V) characteristics across an array of Ni/4H-SiC diodes on the same epitaxial wafer. These results demonstrate not only a correspondence between these optical features and measured barrier heights, but they also suggest that such states may limit the range of SB heights in general. DRCLS of near-ideal diodes show a broad 2.45 eV emission at common to all diode areas and associated with either impurities or inclusions. Strongly non-ideal diodes exhibit additional defect emissions at 2.2 and 2.65 eV. On the other hand, there is no correlation between the appearance of morphological defects observed by polarized light microscopy or X-ray topography and the presence of double barrier characteristics. The DRCLS observations of defect level transitions that correlate with non-ideal Schottky barriers suggest that these sub-surface defect features can be used to predict Schottky barrier behavior.

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Impact of Interface Traps on Current-Voltage Characteristics of 4H-SiC Schottky-Barrier Diodes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.710 ◽

2014 ◽

Vol 778-780 ◽

pp. 710-713 ◽

Cited By ~ 1

Author(s):

Hamid Amini Moghadam ◽

Sima Dimitrijev ◽

Ji Sheng Han

Keyword(s):

Schottky Barrier ◽

Schottky Barrier Height ◽

Schottky Diodes ◽

Forward Bias ◽

Interface Traps ◽

Barrier Heights ◽

Current Voltage ◽

Donor Type ◽

Current Voltage Characteristics ◽

Expected Values

This paper presents a physical model based on interface traps to explain both the larger barrier heights of practical Schottky diodes in comparison to the theoretically expected values and the appearance of a knee in the log I–V characteristics. According to this model, acceptor-type interface traps near the valance band increase the Schottky barrier height, which shifts the log I–V characteristic to higher forward-bias voltages. In addition to the acceptor traps, donor-type interface traps can appear near the conduction band, and when they do, they cause the knee in the log I–V characteristics as their energy level falls below the Fermi level and the charge associated with these traps changes from positive to neutral.

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Study of the Effect of Metal/Semiconductor Interface Properties on a Resistance Switching Device

MRS Proceedings ◽

10.1557/proc-0997-i07-06 ◽

2007 ◽

Vol 997 ◽

Author(s):

Manuel Villafuerte ◽

Silvia P. Heluani ◽

Gabriel Juárez ◽

David Comedi ◽

Gabriel Braunstein ◽

...

Keyword(s):

Resistance Switching ◽

Electrical Contacts ◽

X Ray Diffraction ◽

Semiconductor Interface ◽

Si Substrates ◽

Barrier Heights ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Terminal Structure ◽

Gap States

AbstractN-doped ZnO thin films were deposited by pulsed laser deposition on SiO2/Si substrates. X-ray diffraction analysis revealed that the films had the wurtzite structure, and were highly oriented along the c-axis direction. Au and Al electrical contacts were deposited by sputtering on the top surface of the samples, forming a two-terminal structure in each case. The current-voltage characteristics of the two terminal structure, and the temperature dependence of the resistance switching effect, were studied in the 125-300 K temperature range. The results of these measurements are presented and discussed in terms of the different Schottky barrier heights, as well as in terms of interfacial defect-induced gap states.

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Evaluating AlGaN/AlN/GaN heterostructure Schottky barrier heights with flat-band voltage from forward current-voltage characteristics

Applied Physics Letters ◽

10.1063/1.3643139 ◽

2011 ◽

Vol 99 (12) ◽

pp. 123504 ◽

Cited By ~ 26

Author(s):

Yuanjie Lv ◽

Zhaojun Lin ◽

Lingguo Meng ◽

Yingxia Yu ◽

Chongbiao Luan ◽

...

Keyword(s):

Schottky Barrier ◽

Flat Band ◽

Flat Band Voltage ◽

Barrier Heights ◽

Forward Current ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Gan Heterostructure

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Electrical properties modulation of thin film solar cell using gold nanostructures at textured FTO/p–i–n interface

Functional Materials Letters ◽

10.1142/s1793604715500174 ◽

2015 ◽

Vol 08 (02) ◽

pp. 1550017 ◽

Cited By ~ 5

Author(s):

A. Gentile ◽

G. Cacciato ◽

F. Ruffino ◽

R. Reitano ◽

G. Scapellato ◽

...

Keyword(s):

Thin Film ◽

Electrical Properties ◽

Open Circuit ◽

Optical Measurements ◽

Gradual Reduction ◽

Materials Properties ◽

Barrier Heights ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Open Circuit Voltages

We report about the modulation of the electrical properties of thin film solar cells due to the incorporation of size-selected Au nanostructures (NSs) at a textured FTO/p–i–n interface. By increasing the Au NSs size, the analyses of current-voltage characteristics show lower Schottky barrier heights and the gradual reduction of the open-circuit voltages (V OC ). The optical measurements show higher parasitic absorption by larger Au NSs that reduces the amount of radiation transmitted by the transparent to absorber layer. This process decreases the number of photo-generated carriers and may explain the V OC reduction related to the devices with larger Au NSs at the interface. So, the correlation between materials properties and device performances was established.

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Analysis of Forward Current-Voltage Characteristics of Non-Ideal Ti/4H-SiC Schottky Barriers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.615-617.431 ◽

2009 ◽

Vol 615-617 ◽

pp. 431-434 ◽

Cited By ~ 1

Author(s):

Pavel A. Ivanov ◽

Alexander S. Potapov ◽

Tat'yana P. Samsonova

Keyword(s):

Energy Distribution ◽

Ideality Factor ◽

Energy Barrier ◽

Schottky Barriers ◽

Interface Trap Density ◽

Interface Trap ◽

Titanium Layer ◽

Forward Current ◽

Current Voltage ◽

Current Voltage Characteristics

Forward current-voltage characteristics of non-ideal Ti / 4H-SiC Schottky barriers with ideality factor n = 1.1 - 1.2 have been analyzed. The non-ideality is considered as a result of formation of a thin intermediate dielectric layer between the deposited titanium layer and 4H-SiC. Using experimental current-voltage characteristics, the electro-physical characteristics of Ti contacts such as the energy barrier height, the thickness of the intermediate layer and the energy distribution of the interface trap density are determined.

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