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In this study, electrical changes in diode parameters of Schottky diodes that made of a kesterite semiconductor were examined under different temperatures. For this aim, Cu2ZnSnSe4 (CZTSe) nanocrystals were fabricated using the hot injection technique, and it was covered by spin coating on an ITO glass substrate. We was introduced the physical and structural analyses using scanning electron microscopy and X-ray spectroscopy. Current–voltage measurements were fulfilled at different temperature (from 100 to 325 K) under dark environment. It was observed that its electrical parameters were strongly affected by temperature. [ABSTRACT FROM AUTHOR]

Metal/semiconductor structures, particularly Schottky diodes, play a crucial role in semiconductor identification and the production of electronic devices, like solar cells, photodetectors, photodiodes, and field-effect transistors (FETs). These structures are of great interest due to their ability to modify electrical and optical properties, responding to external factors such as illumination and temperature. However, despite extensive research in this field, there has been limited exploration of silicon-based metal/semiconductor structures incorporating PANI:Borophene interfacial materials. In this study, we prepared PANI:Borophene/p-Si and PANI:Borophene/n-Si structures and examined their photodiode properties using various measurements. The unoccupied trap levels (m) obtained 0.44 and 0.33 for Al/PANI:Borophene/p-Si and Au/PANI:Borophene/n-Si device, respectively. Our investigation revealed that both structures exhibited rectification behavior, with linear characteristics in the forward bias region, and deviations attributed to series resistance effects at higher voltages. Moreover, the presence of borophene in the interfacial layer led to improvements in the devices’ electrical properties. Finally, the PANI:Borophene/Si Schottky diodes was tested for salt detection and the Al/PANI:Borophene/p-Si diode has the characteristics of salt (NaCl) concentration detection sensor and it successfully detected salt concentration changes with respect to current flow. [ABSTRACT FROM AUTHOR]

This study investigated the frequency dependent dielectric spectrum of Au/Si structures in which stannic oxide (SnO2) films formed by spin coating technique on silicon substrate were used as interface. Surface morphological examination of interfacial layer was made by atomic force microscopy and scanning electron microscope. The analyzes revealed a uniform and low surface roughness of 2.66 nm, which is important for high performance applications. Capacitance-frequency (C–f) and conductance-frequency (G/w–f) analysis techniques were used to characterize the produced devices. For this purpose, measurements were made at 1–1000 kHz frequency range and dc voltages between − 0.5 and 6.0 V with steps of 0.02 V. All measurement processes were performed at room temperature and under dark environment. The Complex impedance Cole–Cole plots showed the relaxation behavior as non-Debye type. The contribution of grain and grain boundary to conductance was predicted. Module analysis showed that the electrical transport in the material was in the form of a hopping mechanism. [ABSTRACT FROM AUTHOR]

In this study, metal/Zn-complex/semiconductor (MPS) Schottky photodiodes are fabricated. Interface layer is deposited using a metal-nicotinate/nicotinamide mixed ligand [Zn(C6H6N2O)2(C6H4NO2)2(H2O)]⋅1/2(H2O) complex synthesized with Zn dopant. Different film layers are obtained by dissolving 0.5, 1.0, 2.0, and 3.0 mg Zn-complex in 1 mg spin-coating solution. Thermal analysis techniques are performed between room temperature and 900 °C to study the thermal behavior of the complex as a metal oxide. The surface morphology of the polymeric film layers is investigated by microscopy methods, and the results show relatively smooth and compact surface characteristics for all Zn-complex mass contributions. To evaluate electrical properties of the fabricated device, current–voltage, capacitance–voltage and conductance–voltage measurements are performed under dark and illumination intensities between 20 and 100 mW/cm2 depending on Zn-complex mass at the interface. These measurements indicate light sensitivity of the diodes. In addition, transient characteristics are investigated at these illumination intensities to evaluate photoresponse behaviors. Then, the highest photoconductivity is recorded for 3 mg Zn-complex. The experimental results indicate that the diodes exhibit good photosensitive behavior, and they can be used for opto-electronic applications. [ABSTRACT FROM AUTHOR]

We were produced a various Mn-doped complex and presented it in Au/Mn-complex/n-Si structure as an interfacial layer. For this aim, a metal-nicotinate/nicotinamide mixed ligand complex was synthesized with Mn dopant. Surface morphologies were investigated using surface analysis methods (AFM and SEM) and relatively smooth and uniform surfaces were obtained for each doping level. The devices were characterized using current–voltage and time-dependent photoresponse measurements. In order to examine the response to light, the measurements were carried out in the dark and different lighting (from 20 to 100 mW/cm2) intensities. With the increasing amount of Mn dopant, the barrier heights and junction resistance of devices were decreased. Increasing the amount of light was increased the sensitivity of the devices to the light. The highest photoconductivity was recorded for 1 mg Mn-complex. It was seen from obtained results, the fabricated devices exhibited good photodiode behavior and can be used in optoelectronic applications. [ABSTRACT FROM AUTHOR]

A simple wet-chemical synthesis method was developed to fabricate Zinc oxide micro-rod clusters. The synthesis process involved the rapid dilution of a zinc-bearing alkaline solution at 150°C in a convection oven on indium tin oxide (ITO) substrates. The synthesis was carried out by immersing an unseeded ITO substrate in a mixture of zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and hexamethylenetetramine ((CH2)6N4) aqueous solution. The obtained sample was annealed at 400°C for 2 h. The structural, morphological and optical properties of the synthesized ZnO microstructures were investigated by X-ray diffraction, scanning electron microscopy and ultraviolet-visible spectroscopy, respectively. The ZnO rod clusters are hexagonal phase of the wurtzite structure. The crystal grain sizes of the films were found to be 72.6, 84.3 and 66.3 nm for the (100), (002) and (101) crystal planes, respectively. The optical bandgap of the ZnO was determined to be 3.147 eV. [ABSTRACT FROM AUTHOR]

In this work, a metal–semiconductor diode in the form of Au/4H-SiC is fabricated, and the electrical properties of this device are systematically examined under dark and different illumination intensities. To perform this, the current–voltage (I–V) characteristics of the Schottky-type diode are analyzed at room temperature. The performance parameters such as saturation current ( I 0 ), barrier height ( Φ B ), ideality factor (n ) and series resistance ( R s ) are found to be illumination dependent. The reverse biased I - V characteristics under incident light indicate high photo-sensitivity as compared to the response at forward bias. Thus, this result is investigated in detail according to both Schottky and Poole–Frenkel effects. It is found that the Poole–Frenkel mechanism is dominant in the reverse biased region. The Au/4H-SiC Schottky junction has a strong photo-current response to the different illumination intensities and transient photocurrent characteristics of the fabricated device are studied at the illumination intensities of 50 and 100 mW/cm2. All experimental results indicate that the Au/4H-SiC Schottky diode, with a valuable response to the illumination together with change in illumination intensity, can be used for optoelectronic applications. [ABSTRACT FROM AUTHOR]

A simple wet-chemical synthesis method was developed to fabricate Zinc oxide micro-rod clusters. The synthesis process involved the rapid dilution of a zinc-bearing alkaline solution at 150°C in a convection oven on indium tin oxide (ITO) substrates. The synthesis was carried out by immersing an unseeded ITO substrate in a mixture of zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and hexamethylenetetramine ((CH2)6N4) aqueous solution. The obtained sample was annealed at 400°C for 2 h. The structural, morphological and optical properties of the synthesized ZnO microstructures were investigated by X-ray diffraction, scanning electron microscopy and ultraviolet-visible spectroscopy, respectively. The ZnO rod clusters are hexagonal phase of the wurtzite structure. The crystal grain sizes of the films were found to be 72.6, 84.3 and 66.3 nm for the (100), (002) and (101) crystal planes, respectively. The optical bandgap of the ZnO was determined to be 3.147 eV. [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the microbial adherence to the surfaces of a nonprecious metal alloy after plasma nitriding. MATERIALS AND METHODS: The plasma-nitriding process was performed to the surfaces of metals prepared from a nickel-chromium alloy. The microorganisms were labeled with technetium-99m. After the labeling procedure, 60 metal disks were treated with a microorganism for each use. RESULTS: The results revealed that the amount of adherence of all microorganisms on surfaces was changed by plasma-nitriding process; adherence decreased substantially (P < .05) and the differences in plasma nitriding time were not significant (P> .05) CONCLUSION: With the plasma-nitriding process, the surface properties of nonprecious metal alloys can be changed, leading to decreased microbial adherence. [ABSTRACT FROM AUTHOR]

Background: Ankle injuries are more frequently observed in youth and athletes, and may lead to permanent disabilities if not treated properly. Approximately 10% of ankle injuries are associated with syndesmotic ligament injuries and fixation with screw is frequently applied as surgical treatment. The present study we aimed to determine the most proper model and model parameters by evaluating the minimum equivalent von Mises stress value developed in syndesmotic fixation of the ankle. Methods: By modeling the normal lower extremity in a healthy subject via the finite element analysis (FEA) method, we compared stress developed in a normal standing position in the models of syndesmotic injuries approached by frequently used cortical screws of various lengths and diameters, and by considering the number of screws and localization of fixation. Tibia, fibula, talus, and calcaneus were modeled as a three dimensional (3D) solid model via images of computerized tomography (CT), using the MIMICS program (version 10.01). The obtained 3D model was saved in the MIMICS program in STL (steriolithography) format, and transferred to the Geomagic Studio (version 10) program. Essential corrections were applied to the bones with the aid of the Geomagic program. The model of lower extremity designed was transferred to the Solidworks (version 2014) program in IGES (Initial Graphics Exchange Specification) format, and thus the meniscus and cartilage were modeled. Tensions that developed in the ankle were calculated after forming a mesh pattern via the ANSYS Workbench (version 15.0) software. Results: Sixteen different models obtained were analyzed by the Taguchi method, and the most appropriate models and model parameters were indicated by determining the minimum equivalent von Mises stress value. Conclusion: Screw diameter was determined to be the most important parameter. When 16 different models were considered, a screw diameter of 4.5 mm and threecortex fixation with two screws parallel to the tibial joint surface were found to produce the most convenient model. [ABSTRACT FROM AUTHOR]

In this work, the perylene-monoimide/n-Si (100) Schottky structures have been fabricated by spin coating process. We have studied the capacitance-voltage ( C- V) and conductance-voltage ( G- V) characteristics of the Au/perylene-monoimide/n-Si diodes at 500 kHz before and after Co γ-ray irradiation. The effects of Co γ -ray irradiation on the electrical characteristics of a perylene-monoimide/n-Si Schottky diode have been investigated. A decrease both in the capacitance and conductance has been observed after Co γ -ray irradiation. This has been attributed to a decrease in the net ionized dopant concentration that occurred as a result of Co γ-ray irradiation. Some contact parameters such as barrier height (Φ) interface state density ( N) and series resistance ( R) have been calculated from the C- V and G- V characteristics of the diode before and after irradiation. It has been observed that the Φ and N values are decreased after the applied radiation, while the R value is increased. [ABSTRACT FROM AUTHOR]

The article discusses the features of computered-controlled uniaxial tensile test machine and its supporting equipment to study the inelastic behaviors of rubber-like materials. It states that the major features of uniaxial machines include the simplicity of its mechanical system, its cost, and its flexible software which was developed by utilizing LabView data acquisition and control software. Inelastic behaviors of rubber-like materials and details on processing the data are also cited.

Cylindrical parts made from pre-strengthened Fe-Cu-C and Fe-Zn-C powders, fabricated under 1000 MPa-cold press, were welded in a vacuum furnace at different temperatures by diffusion welding. A novel approach was used where powder metallurgy parts were sintered together with diffusion welding with no extra pressure applied during the welding process. Chemical composition, cold press pressure, and sintering time (consequently welding time) were constant during the experimental works. Samples were examined by means of optical microscopy for metallographic inspection and by energy dispersive spectroscopy for compositional analysis. The shear strength and hardness profiles of joints were determined. It was observed that shear strength and hardness values of welding increased with increasing welding temperature. [ABSTRACT FROM AUTHOR]

The current–voltage (I–V) characteristics of Ag Schottky contacts on a Bridgman–Stockbarger grown p-type SnSe layered semiconducting material have been measured over the temperature range of 80–350 K. Their analysis based on the thermionic emission (TE) theory has revealed an abnormal decrease of zero-bias barrier height and increase of ideality factor at lower temperatures. This behaviour has been interpreted on the basis of the assumption of a Gaussian distribution of barrier heights due to barrier height inhomogeneities that prevail at the interface. The inhomogeneities are considered to have Gaussian distribution with a mean barrier height of [inline image] and standard deviation of σs0 = 0.075 V at zero-bias. Furthermore, the mean barrier height and the Richardson constant values were obtained by means of the modified Richardson plot, ln(I0/T2) - (q2σ2s0/2k2T2)versus 1000/T, as 0.603 eV and 7.72 A K-2 cm-2 respectively, of which latter is close to its theoretical value of 18 A K-2 cm-2 used for the determination of the zero-bias barrier height. Hence, it has been concluded that the temperature dependence of the I–V characteristics of the Schottky barrier on p-type SnSe can be successfully explained on the basis of TE mechanism with Gaussian distribution of the barrier heights. [ABSTRACT FROM AUTHOR]

The current–voltage (I–V) characteristics of Ag Schottky contacts on a Bridgman–Stockbarger grown p-type SnSe layered semiconducting material have been measured over the temperature range of 80–350 K. Their analysis based on the thermionic emission (TE) theory has revealed an abnormal decrease of zero-bias barrier height and increase of ideality factor at lower temperatures. This behaviour has been interpreted on the basis of the assumption of a Gaussian distribution of barrier heights due to barrier height inhomogeneities that prevail at the interface. The inhomogeneities are considered to have Gaussian distribution with a mean barrier height of [inline image] and standard deviation of σs0 = 0.075 V at zero-bias. Furthermore, the mean barrier height and the Richardson constant values were obtained by means of the modified Richardson plot, ln(I0/T2) - (q2σ2s0/2k2T2)versus 1000/T, as 0.603 eV and 7.72 A K-2 cm-2 respectively, of which latter is close to its theoretical value of 18 A K-2 cm-2 used for the determination of the zero-bias barrier height. Hence, it has been concluded that the temperature dependence of the I–V characteristics of the Schottky barrier on p-type SnSe can be successfully explained on the basis of TE mechanism with Gaussian distribution of the barrier heights. [ABSTRACT FROM AUTHOR]

The current–voltage (I–V) characteristics of Ag/p-SnS Schottky barrier diodes were measured in the temperature range of 100–300 K and have been interpreted on the basis of the assumption of a Gaussian distribution of barrier heights (BHs) due to barrier height inhomogeneities that prevail at the interface. It is shown that the occurrence of a Gaussian distribution of the BHs is responsible for the decrease of the apparent barrier height ΦB0, increase of the ideality factor n and nonlinearity in the activation energy plot at low temperatures. The inhomogeneities are considered to have a Gaussian distribution with a mean barrier height of [inline image] and a standard deviation of σs0 = 0.093 V at zero bias. Furthermore, the mean barrier height and the Richardson constant values were obtained as 0.642 eV and 12.89 A K-2 cm-2, respectively, by means of the modified Richardson plot, ln(I0/T2) - (q2σ2s0/2k2T2) versus 103/T. Hence, it has been concluded that the temperature dependence of the I–V characteristics of the Schottky barrier on p-type SnS 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. [ABSTRACT FROM AUTHOR]