scholarly journals Исследование вольт-амперных характеристик новых гетероструктур MnO-=SUB=-2-=/SUB=-/GaAs(100) и V-=SUB=-2-=/SUB=-O-=SUB=-5-=/SUB=-/GaAs(100), прошедших термическую обработку

2019 ◽  
Vol 53 (8) ◽  
pp. 1074
Author(s):  
Б.В. Сладкопевцев ◽  
Г.И. Котов ◽  
И.Н. Арсентьев ◽  
И.С. Шашкин ◽  
И.Я. Миттова ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Thermal Oxidation ◽  
Current Density ◽  
Chemical Bonding ◽  
Room Temperature ◽  
Reverse Bias ◽  
Electrical Parameters ◽  
Internal Interface ◽  
Current Voltage ◽  
Bias Range

AbstractComplex oxide films with a thickness of about 200 nm are formed during the thermal oxidation of GaAs with magnetron-deposited V_2O_5 and MnO_2 nanolayers. The electrical parameters of the films (reverse-bias breakdown voltage and current density) are determined by the method of current–voltage ( I – V ) characteristics at room temperature in the bias range from –5 to +5 V, and their composition and surface morphology are investigated. It is shown that V_2O_5 facilitates the more intense (in comparison with MnO_2) chemical bonding of arsenic at the internal interface with the formation of As_2O_5. As a result, thermally oxidized V_2O_5/GaAs heterostructures exhibit higher breakdown voltages.

Effect of Pulse Electrical Parameters on Performance of Deposited Copper Coatings with Citrate System at Room Temperature

2014 ◽  
Vol 528 ◽  
pp. 8-13
Author(s):  
Jian Jun Xi ◽  
Jun Zhao ◽  
Zhi Gang Wang ◽  
Chun Ping Zhao ◽  
Mei Ping Xue
Keyword(s):  
Surface Morphology ◽  
Current Density ◽  
Coating Thickness ◽  
Room Temperature ◽  
Duty Ratio ◽  
Thickness Gauge ◽  
Copper Plating ◽  
Electrical Parameters ◽  
Uniform Coating ◽  
Copper Coatings

This article presents a detailed research on pulse electrical parameters for non-cyanide electroplating copper plating on stainless still substrate. The study was made about the effect of the current density, duty ratio and frequency on the surface morphology, thickness and uniformity of the deposited layers. The surface morphology was examined by MIT 300 metallurgical microscope and the thickness of copper coatings was examined by TT260 coating thickness gauge. Current density 0.4A/dm2 is the optimum current at which the best uniform coating can be formed.

The Properties of n-ZnO/p-SiC Heterojunctions and their Potential Applications for Devices

2006 ◽  
Vol 527-529 ◽  
pp. 1571-1574 ◽  
Author(s):  
Cole W. Litton ◽  
Ya.I. Alivov ◽  
D. Johnstone ◽  
Ümit Özgür ◽  
V. Avrutin ◽  
...  
Keyword(s):  
Room Temperature ◽  
Molecular Beam ◽  
Reverse Bias ◽  
Zno Films ◽  
Turn On ◽  
Forward Current ◽  
Current Voltage ◽  
Potential Applications ◽  
Current Voltage Characteristics ◽  
P Type

Heteroepitaxial n-ZnO films have been grown on commercial p-type 6H-SiC substrates by plasma-assisted molecular-beam epitaxy, and n-ZnO/p-SiC heterojunction mesa structures have been fabricated and their photoresponse properties have been studied. Current-voltage characteristics of the structures had a very good rectifying diode-like behavior with a leakage current less than 2 x 10-4 A/cm2 at -10 V, a breakdown voltage greater than 20 V, a forward turn on voltage of ∼5 V, and a forward current of ∼2 A/cm2 at 8 V. Photosensitivity of the diodes, when illuminated from ZnO side, was studied at room temperature and photoresponsivity of as high as 0.045 A/W at -7.5 V reverse bias was observed for photon energies higher than 3.0 eV.

Electrical properties, characterization, and preparation of composite materials containing a polymethacrylate with α-naphthyl side group and nanographene fillers

2019 ◽  
pp. 089270571988297
Author(s):  
Abdullahi Musa Abubakar ◽  
Fatih Biryan ◽  
Kadir Demirelli
Keyword(s):  
Ideality Factor ◽  
Ac Conductivity ◽  
Room Temperature ◽  
Decomposition Temperature ◽  
Electrical Parameters ◽  
Scanning Calorimetry ◽  
Current Voltage ◽  
Polymerization Method ◽  
Hopping Model ◽  
Pure Poly

2-(Naphthalene-1-yl oxy)-2-oxoethyl methacrylate (NOEMA) was synthesized from reaction of naphthalene-1-yl 2-chloroacetate and sodium methacrylate and its homopolymer was prepared by free-radical polymerization method at 60°C. The glass transition temperature of pure poly(NOEMA) was estimated as 102°C by differential scanning calorimetry technique, whereas that of poly(NOEMA) containing 10 wt% nanographene was 83°C. While pure poly(NOEMA) from thermogravimetric analysis measurements was indicating a decomposition at 290°C, poly(NOEMA) composite containing 10 wt% nanographene showed thermal decomposition temperature at 261°C. Semiconducting composites of poly(NOEMA) have been prepared by adding nanographene particles to poly(NOEMA) for preparing nanocomposites with different weight percentages (2, 3, 4, 5, and 10 wt%). The dielectric constant, ∊′, and dielectric loss factor, ∊″, of pure poly(NOEMA) were 3.66 and 0.052, respectively, whereas those of poly(NOEMA) containing 10 wt% nanographene were 186 and 210,152, respectively. Alternating current (AC) conductivity of pure poly(NOEMA) was 2.03 × 10−9 S cm−1, whereas that of poly(NOEMA) containing 10 wt% nanographene was 0.00134 S cm−1. AC conductivity mechanism of poly(NOEMA)/10 wt% nanographene composite indicated the correlated barrier hopping model. Activation energy values of poly(NOEMA)/ x wt% nanographene composites was estimated to be between 4.783 eV and 0.209 eV. The polymer composite/p-Si thin-film heterojunction diode properties have been investigated from current–voltage at room temperature. The electrical parameters of the prepared diodes such as ideality factor ( n), the barrier height (BH; Φ b), rectification ratio, and reverse saturation current ( I o) were investigated at dark and room temperature. The ideality factor ( n) value of the Al/poly(NOEMA)/ x wt% nanographene/p-Si/Al diode for dark was found to be between 5.147 and 7.504, respectively. The BH ( Φ b) value of the Al/poly(NOEMA)/ x wt% nanographene/p-Si/Al diode at dark was found to be between 0.228 and 0.64.

scholarly journals Influence of Defects on Solar Cell Characteristics

2009 ◽  
Vol 156-158 ◽  
pp. 1-10 ◽  
Author(s):  
Otwin Breitenstein ◽  
Jan Bauer ◽  
Pietro P. Altermatt ◽  
Klaus Ramspeck
Keyword(s):  
Solar Cells ◽  
Reverse Bias ◽  
Present Knowledge ◽  
Silicon Solar Cells ◽  
Extended Defects ◽  
Exponential Behavior ◽  
Current Voltage ◽  
Recombination Current ◽  
Bias Range ◽  
The Given

The current-voltage (I-V) characteristics of most industrial silicon solar cells deviate rather strongly from the exponential behavior expected from textbook knowledge. Thus, the recombination current may be orders of magnitude larger than expected for the given material quality and often shows an ideality factor larger than 2 in a wide bias-range, which cannot be explained by classical theory either. Sometimes, the cells contain ohmic shunts although the cell’s edges have been perfectly insolated. Even in the absence of such shunts, the characteristics are linear or super-linear under reverse bias, while a saturation would be classically expected. Especially in multicrystalline cells the breakdown does not tend to occur at -50 V reverse bias, as expected, but already at about -15 V or even below. These deviations are typically caused by extended defects in the cells. This paper reviews the present knowledge of the origin of such non-ideal I-V characteristics of silicon solar cells and introduces new results on recombination involving coupled defect levels.

Laser Engineering of Barrier Structures Based on Solid Solution ZnCdHgTe.

2002 ◽  
Vol 719 ◽  
Author(s):  
Galina Khlyap
Keyword(s):  
Room Temperature ◽  
Film Surface ◽  
Charge Carriers ◽  
Barrier Structure ◽  
Free Charge ◽  
Current Voltage ◽  
Capacitance Voltage ◽  
Laser Engineering ◽  
Charged Defects ◽  
Epilayer Surface

AbstractRoom-temperature electric investigations carried out in CO2-laser irradiated ZnCdHgTe epifilms revealed current-voltage and capacitance-voltage dependencies typical for the metal-semiconductor barrier structure. The epilayer surface studies had demonstrated that the cell-like relief has replaced the initial tessellated structure observed on the as-grown samples. The detailed numerical analysis of the experimental measurements and morphological investigations of the film surface showed that the boundaries of the cells formed under the laser irradiation are appeared as the regions of accumulation of derived charged defects of different type of conductivity supplying free charge carriers under the applied electric field.

Influence of Momentary Annealing on the Nanoscale Surface Morphology of Room Temperature Pulsed Laser Deposited NiO(111) Epitaxial Thin Films on Atomically Stepped Sapphire (0001) Substrates

2013 ◽  
Vol 1507 ◽  
Author(s):  
Ryosuke Yamauchi ◽  
Geng Tan ◽  
Daishi Shiojiri ◽  
Nobuo Tsuchimine ◽  
Koji Koyama ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Room Temperature ◽  
Pulsed Laser ◽  
Film Surface ◽  
Transient State ◽  
Epitaxial Thin Films ◽  
Flat Surfaces ◽  
Surface Nanostructure ◽  
Atomically Flat

ABSTRACTWe examined the influence of momentary annealing on the nanoscale surface morphology of NiO(111) epitaxial thin films deposited on atomically stepped sapphire (0001) substrates at room temperature in O2 at 1.3 × 10−3 and 1.3 × 10−6 Pa using a pulsed laser deposition (PLD) technique. The NiO films have atomically flat surfaces (RMS roughness: approximately 0.1–0.2 nm) reflecting the step-and-terrace structures of the substrates, regardless of the O2 deposition pressure. After rapid thermal annealing (RTA) of the NiO(111) epitaxial film deposited at 1.3 × 10−3 Pa O2, a periodic straight nanogroove array related to the atomic steps of the substrate was formed on the film surface for 60 s. In contrast, the fabrication of a transient state in the nanogroove array formation was achieved with RTA of less than 1 s. However, when the O2 atmosphere during PLD was 1.3 × 10−6 Pa, random crystal growth was observed and resulted in a disordered rough surface nanostructure after RTA.

Study on Electrodeposition of Ni-Graphite Composite Coatings in Sulfamate Bath

2010 ◽  
Vol 150-151 ◽  
pp. 1546-1550 ◽  
Author(s):  
Xiang Zhu He ◽  
Xiao Wei Zhang ◽  
Xin Li Zhou ◽  
Zhi Hong Fu
Keyword(s):  
Surface Morphology ◽  
Process Parameters ◽  
Current Density ◽  
Graphite Particle ◽  
Particle Concentration ◽  
Composite Coatings ◽  
Nickel Matrix ◽  
Graphite Composite ◽  
Surface Morphologies ◽  
Sulfamate Bath

This paper presented the composite coatings of nickel with graphite particle on the aluminum substrate using a nickel sulfamate bath. Effects of graphite particle concentration on the surface morphologies of the composite coatings were investigated. The inclusion of graphite particle into metal deposits was dependent on many process parameters, including particle concentration, current density, pH and temperature. Results of SEM and XRD demonstrated that graphite particle had successfully deposited on that nickel matrix; besides, the surface morphology of coatings obtained from sulfamate bath containing 2g/L graphite particle dispersed more uniformly than the ones with higher concentration.

Photoconductivity of Nanocomposite MEH-PPV: TiO2 Thin Films

2011 ◽  
Vol 13 ◽  
pp. 87-92 ◽  
Author(s):  
M.S.P Sarah ◽  
F.S. Zahid ◽  
M.Z. Musa ◽  
U.M. Noor ◽  
Z. Shaameri ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Surface Morphology ◽  
Spin Coating ◽  
Glass Substrate ◽  
Spin Coating Technique ◽  
Coating Technique ◽  
Current Voltage ◽  
Current Voltage Characteristics

The photoconductivity of a nanocomposite MEH-PPV:TiO2 thin film is investigated. The nanocomposite MEH-PPV:TiO2 thin film was deposited on a glass substrate by spin coating technique. The composition of the TiO2 powder was varied from 5 wt% to 20 wt% (with 5 wt% interval). The concentration of the MEH-PPV is given by 1 mg/1 ml. The current voltage characteristics were measured in dark and under illumination. The photoconductivity showed increment in value as the composition of the TiO2 is raised in the polymer based solution. The absorption showed augmentation as the amount of TiO2 is increased. The escalation of the current voltage is then supported by the results of surface morphology.

AFM Study of Surface Morphology of Aluminum Nitride Thin Films

1995 ◽  
Vol 388 ◽  
Author(s):  
Yoshihisa Watanabe ◽  
Yoshikazu Nakamura ◽  
Shigekazu Hirayama ◽  
Yuusaku Naota
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Substrate Temperature ◽  
Single Crystal ◽  
Room Temperature ◽  
Ion Beam ◽  
Soda Lime ◽  
Silicon Single Crystal ◽  
Soda Lime Glass ◽  
Average Roughness

AbstractAluminum nitride (AlN) thin films have been synthesized by ion-beam assisted deposition method. Film deposition has been performed on the substrates of silicon single crystal, soda-lime glass and alumin A. the influence of the substrate roughness on the film roughness is studied. the substrate temperature has been kept at room temperature and 473K and the kinetic energy of the incident nitrogen ion beam and the deposition rate have been fixed to 0.5 keV and 0.07 nm/s, respectively. the microstructure of the synthesized films has been examined by X-ray diffraction (XRD) and the surface morphology has been observed by atomic force microscopy(AFM). IN the XRD patterns of films synthesized at both room temperature and 473K, the diffraction line indicating the alN (10*0) can be discerned and the broad peak composed of two lines indicating the a1N (00*2) and a1N (10*1) planes is also observed. aFM observations for 100 nm films reveal that (1) the surface of the films synthesized on the silicon single crystal and soda-lime glass substrates is uniform and smooth on the nanometer scale, (2) the average roughness of the films synthesized on the alumina substrate is similar to that of the substrate, suggesting the evaluation of the average roughness of the film itself is difficult in the case of the rough substrate, and (3) the average roughness increases with increasing the substrate temperature.

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