scholarly journals Path Way For Electrical Conduction In ZnO Basedternary Nanocomposite Room Temperature Ethanol Sensors

2021 ◽  
Author(s):  
Chitra Muthukumaravel ◽  
Geramilla Mangamma ◽  
Rajesh Arumugam ◽  
Uthayarani Karunakaran ◽  
Rajib Sahu
Keyword(s):  
Vanadium Oxide ◽  
Barrier Height ◽  
Room Temperature ◽  
Schottky Barrier Height ◽  
Electronic Effects ◽  
Hydrothermal Route ◽  
Atomic Force ◽  
Ethanol Sensing ◽  
Hierarchical Morphology ◽  
Oxide Vanadium

Abstract In the present investigations, the samples such as zinc oxide, tin oxide, vanadium oxide and their ternary combinations prepared by hydrothermal route were characterised using the state-of-the-art facilities and were systematically analysed. The interface properties between the grain and grain boundaries of these oxides were studied using Conductive atomic force microscopic (CAFM) studies. From the detailed investigations on topography and I-V characteristics, it is revealed that, zinc-tin-vanadium oxide nanocomposite with smaller barrier height of 0.189 eV exhibited pronounced response magnitude of 98.96 % at a faster rate of 32 s at room temperature. The outstanding ethanol sensing property of the ternary nanocomposite is attributed to the hierarchical morphology with large surface area, the formation of heterojunction at the interface, tuning the schottky barrier height, depletion layer manipulation and the electronic effects.

Ohmic Contact Formation Mechanism of Pd-based Contact to p-GaN

2000 ◽  
Vol 622 ◽  
Author(s):  
Dae-Woo Kim ◽  
Joon Cheol Bae ◽  
Woo Jin Kim ◽  
Hong Koo Baik ◽  
Chong Cook Kim ◽  
...  
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Formation Mechanism ◽  
Ohmic Contact ◽  
Room Temperature ◽  
Schottky Barrier Height ◽  
Contact Formation ◽  
Ohmic Behavior ◽  
Plane Direction ◽  
Ohmic Contact Formation

ABSTRACTWe have investigated surface treatment effect on the interfacial reaction of Pd/p-GaN interface and also room temperature ohmic contact formation mechanism of Pd-based ohmic contact. In order to examine room temperature ohmic behavior, various metal contact systems were deposited and current-voltage measurements were carried out. In spite of large theoretical Schottky barrier height between Pd and p-GaN, Pd-based contact showed perfect ohmic characteristic even before annealing. According to the results of synchrotron X-ray radiation, the closed-packed atomic planes (111) of the Pd film were quite well ordered in surface normal direction as well as in the in-plane direction. The effective Schottky barrier height of Au/Pd/Mg/Pd/p-GaN was 0.47eV, which was estimated by Norde method. This discrepancy between theoretical barrier height and the measured one might be due to the epitaxial growth of Pd contact metal and so the room-temperature ohmic characteristic of Pd-based ohmic contact was related strongly to the in-plane epitaxial quality of metal on p-GaN.

Effect of Indentation on I-V Characteristics of Au/n-GaAs Schottky Barrier Diodes

2008 ◽  
Vol 63 (3-4) ◽  
pp. 199-202 ◽  
Author(s):  
Ahmet Faruk Ozdemir ◽  
Adnan Calik ◽  
Guven Cankaya ◽  
Osman Sahin ◽  
Nazim Ucar
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Schottky Diode ◽  
Ideality Factor ◽  
Room Temperature ◽  
Schottky Barrier Height ◽  
Vickers Microhardness ◽  
Schottky Barrier Diodes ◽  
Microhardness Test ◽  
Current Voltage

Au/n-GaAs Schottky barrier diodes (SBDs) have been fabricated. The effect of indentation on Schottky diode parameters such as Schottky barrier height (φb) and ideality factor (n) was studied by current-voltage (I-V) measurements. The method used for indentation was the Vickers microhardness test at room temperature. The experimental results showed that the I-V characteristics move to lower currents due to an increase of φb with increasing indentation weight, while contacts showed a nonideal diode behaviour.

Low-temperature formation of Mg/n-type 4H-SiC ohmic contacts with atomically flat interface by lowering of Schottky barrier height

2021 ◽  
Author(s):  
Takuma Doi ◽  
Shigehisa Shibayama ◽  
Mitsuo Sakashita ◽  
Kazutoshi Kojima ◽  
Mitsuaki Shimizu ◽  
...  
Keyword(s):  
Low Temperature ◽  
Schottky Barrier ◽  
Barrier Height ◽  
Ohmic Contacts ◽  
Schottky Barrier Height ◽  
Force Microscopy ◽  
Flat Interface ◽  
Low Temperature Annealing ◽  
Atomic Force ◽  
Low Temperature Process

Abstract To obtain an ohmic contact with a flat interface using a low-temperature process, we investigated the behavior of Schottky barrier height (SBH) at the Mg/n-type 4H-SiC interface to low-temperature annealing. Our results revealed that annealing at 200 °C reduced SBH; a low SBH of 0.28 eV was obtained on the lightly doped substrate. Atomic force microscopy measurements revealed negligible increase in the surface roughness after Mg deposition and annealing. Using the low-temperature process, a contact resistivity of 6.5 × 10−5 Ω⋅cm2 was obtained on the heavily doped substrate, which is comparable to Ni/4H-SiC subjected to annealing of above 950 °C.

scholarly journals Multi-Barrier Height Characterization and DLTS Study on Ti/W 4H-SiC Schottky Diode

2019 ◽  
Vol 963 ◽  
pp. 576-579
Author(s):  
Teng Zhang ◽  
Christophe Raynaud ◽  
Dominique Planson
Keyword(s):  
High Temperature ◽  
Barrier Height ◽  
Room Temperature ◽  
Schottky Barrier Height ◽  
Schottky Diodes ◽  
Metal Contact ◽  
High Temperature Annealing ◽  
Static Characteristics ◽  
Current Voltage ◽  
Capacitance Voltage

Schottky barrier height (SBH) has been characterized on 4H-SiC Schottky diodes with metal contact of Ti/W by Current-Voltage (I-V) and Capacitance-Voltage (C-V) measurements between 80 K and 400 K. Multi-barrier has been recognized and calculated according to different models. No clear difference has been found between single barrier diode and diode with multi-barrier from DLTS tests. Evolution on the I-V characteristics has been observed after high temperature annealing. The effect of annealing at room temperature (RT) and high temperature DLTS scan (stress under high temperature) have also been studied on both static characteristics and DLTS results.

scholarly journals Electrical and Structural Properties of All-Sputtered Al/SiO2/p-GaN MOS Schottky Diode

Coatings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 685 ◽  
Author(s):  
Tran Anh Tuan Thi ◽  
Dong-Hau Kuo ◽  
Phuong Thao Cao ◽  
Pham Quoc-Phong ◽  
Vinh Khanh Nghi ◽  
...  
Keyword(s):  
Schottky Diode ◽  
Carrier Mobility ◽  
Room Temperature ◽  
Schottky Barrier Height ◽  
Cost Effective ◽  
Oxide Semiconductor ◽  
Radio Frequency Sputtering ◽  
Atomic Force ◽  
The Cost ◽  
Gan Film

The all-sputtered Al/SiO2/p-GaN metal-oxide-semiconductor (MOS) Schottky diode was fabricated by the cost-effective radio-frequency sputtering technique with a cermet target at 400 °C. Using scanning electron microscope (SEM), the thicknesses of the electrodes, insulator SiO2 layer, and p-GaN were found to be ~250 nm, 70 nm, and 1 µm, respectively. By Hall measurement of a p-Mg-GaN film on an SiO2/Si (100) substrate at room temperature, the hole’s concentration (Np) and carrier mobility (μ) were found to be Np = 4.32 × 1016 cm−3 and μ = 7.52 cm2·V−1·s−1, respectively. The atomic force microscope (AFM) results showed that the surface topography of the p-GaN film had smoother, smaller grains with a root-mean-square (rms) roughness of 3.27 nm. By I–V measurements at room temperature (RT), the electrical properties of the diode had a leakage current of ~4.49 × 10−8 A at −1 V, a breakdown voltage of −6 V, a turn-on voltage of ~2.1 V, and a Schottky barrier height (SBH) of 0.67 eV. By C–V measurement at RT, with a frequency range of 100–1000 KHz, the concentration of the diode’s hole increased from 3.92 × 1016 cm−3 at 100 kHz to 5.36 × 1016 cm−3 at 1 MHz, while the Fermi level decreased slightly from 0.109 to 0.099 eV. The SBH of the diode at RT in the C–V test was higher than in the I–V test because of the induced charges by dielectric layer. In addition, the ideality factor (n) and series resistance (Rs) determined by Cheung’s and Norde’s methods, other parameters for MOS diodes were also calculated by C–V measurement at different frequencies.

High-Resolution Core Level Study of the Co/Si(111) Interface

1986 ◽  
Vol 83 ◽  
Author(s):  
F. Boscherini ◽  
J. J. Joyce ◽  
M. W. Ruckman ◽  
J. H. Weaver
Keyword(s):  
High Temperature ◽  
High Resolution ◽  
Schottky Barrier ◽  
Barrier Height ◽  
Room Temperature ◽  
Schottky Barrier Height ◽  
Core Level ◽  
Reaction Products ◽  
Semiconductor Structures ◽  
Epitaxial Interface

There has recently been considerable interest in the reaction between Co and a clean Si surface. This interest stems from the epitaxy of CoSi2 and NiSi2 on Si and its potential for the construction of reliable and stable metal-semiconductor structures. In fact, the fabrication of a Si/CoSi2/Si transistor has been recently reported.[l] On a more fundamental side, it has been possible to address the problem of the relation between Schottky barrier height and structure at the NiSi2/Ni interface, which exhibits both a rotated (B-type) and unrotated (A-type) geometry.[2] For CoSi2/Si only the 180° rotated, B-type disilicide is formed. By studying the room temperature interface, we have attempted to describe the nature and physical extent of reaction products; such knowledge is important to understand the formation of interface silicides which ultimately control the nature of the high temperature epitaxial interface.

Electrical Properties of Graphene Contacts to AlGaN/GaN Heterostructures

2015 ◽  
Vol 821-823 ◽  
pp. 986-989
Author(s):  
Gabriele Fisichella ◽  
Giuseppe Greco ◽  
Fabrizio Roccaforte ◽  
Filippo Giannazzo
Keyword(s):  
Barrier Height ◽  
Schottky Barrier Height ◽  
Schottky Contact ◽  
Electrical Characterization ◽  
Conductive Atomic Force Microscopy ◽  
Force Microscopy ◽  
Atomic Force ◽  
Free Sample ◽  
The Impact

A nanoscale electrical characterization of graphene (Gr) contacts to AlxGa1-xN/GaN heterostructures has been carried out using conductive atomic force microscopy. The impact of the AlGaN microstructure on the current transport at Gr/AlGaN interface was evaluated considering two Al0.25Ga0.75N/GaN heterostructures with very different quality in terms of surface roughness and defectivity, i.e. a uniform and defect-free sample and a sample with a high density of V-defects, that locally cause a reduction of the AlGaN thickness. Rectifying contacts were found on the bare (Gr-free) AlGaN surfaces of both samples, but with a more inhomogeneous and lower Schottky barrier height (ΦB≈0.6 eV) in the presence of V-defects with respect to the case of the uniform AlGaN (ΦB≈0.9 eV). Very different electrical behaviour was observed for Gr on the two AlGaN samples, i.e. a low barrier height Schottky contact (ΦB≈0.4 eV) for the uniform AlGaN and an Ohmic contact for the defective AlGaN. Both Schottky and ohmic Gr/AlGaN contacts exhibit an excellent lateral uniformity, that can be ascribed to an averaging effect of the Gr electrode over the AlGaN interfacial inhomogeneities.

The Electronic Characteristics of IrSi Thin Films

2005 ◽  
Vol 475-479 ◽  
pp. 3363-3366
Author(s):  
Xi Ying Ma
Keyword(s):  
Thin Films ◽  
Pulsed Laser Deposition ◽  
Schottky Barrier ◽  
Barrier Height ◽  
Room Temperature ◽  
Schottky Barrier Height ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Measurement Temperature

The Schottky barrier height (SBH) of IrSi nanometer thin films prepared by pulsed laser deposition at room temperature and annealed at 600 °C has been studied. The SBH of the sample is deduced from C-V and I-V data. These SBHs decrease with increasing measurement temperature.

Cryogenic atomic force microscopy

1991 ◽  
Vol 49 ◽  
pp. 54-55
Author(s):  
K. A. Fisher ◽  
M. G. L. Gustafsson ◽  
M. B. Shattuck ◽  
J. Clarke
Keyword(s):  
Room Temperature ◽  
Rapid Freezing ◽  
Cryogenic Temperatures ◽  
Soft Or ◽  
Electrically Conductive ◽  
Force Microscopy ◽  
Flexible Molecules ◽  
Advantages And Disadvantages ◽  
Atomic Force ◽  
Chemical Perturbation

The atomic force microscope (AFM) is capable of imaging electrically conductive and non-conductive surfaces at atomic resolution. When used to image biological samples, however, lateral resolution is often limited to nanometer levels, due primarily to AFM tip/sample interactions. Several approaches to immobilize and stabilize soft or flexible molecules for AFM have been examined, notably, tethering coating, and freezing. Although each approach has its advantages and disadvantages, rapid freezing techniques have the special advantage of avoiding chemical perturbation, and minimizing physical disruption of the sample. Scanning with an AFM at cryogenic temperatures has the potential to image frozen biomolecules at high resolution. We have constructed a force microscope capable of operating immersed in liquid n-pentane and have tested its performance at room temperature with carbon and metal-coated samples, and at 143° K with uncoated ferritin and purple membrane (PM).

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