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This paper discusses and analyzes the quasistatic optimal plasmonic dipole resonance of a small dielectric particle embedded in a lossy surrounding medium. The optimal resonance at any given frequency is defined by the complex valued dielectric constant that maximizes the absorption of the particle under the quasistatic approximation and a passivity constraint. In particular, for an ellipsoid aligned along the exciting field, the optimal material property is given by the complex conjugate of the pole position associated with the polarizability of the particle. In this paper, we employ the classical Mie theory to analyze this approximation for spherical particles in a lossy surrounding medium. It turns out that the quasistatic optimal plasmonic resonance is valid, provided that the electrical size of the particle is sufficiently small at the same time as the external losses are sufficiently large. Hence, it is important to note that this approximation cannot be used for a lossless medium, and which is also obvious, since the quasistatic optimal dipole absorption becomes unbounded for this case. Moreover, it turns out that the optimal normalized absorption cross sectional area of the small dielectric sphere has a very subtle limiting behavior and is, in fact, unbounded even in full dynamics when both the electrical size and the exterior losses tend to zero at the same time. A detailed analysis is carried out to assess the validity of the quasistatic estimation of the optimal resonance, and numerical examples are included to illustrate the asymptotic results. [ABSTRACT FROM AUTHOR]

In this work, ethanol is used as a chemical probe to study the passivation of molecular beam epitaxygrown GaN(0001) by surface oxidation. With a high degree of oxidation, no reaction from ethanol to acetaldehyde in temperature-programmed desorption experiments is observed. The acetaldehyde formation is attributed to a mechanism based on -H abstraction from the dissociatively bound alcohol molecule. The reactivity is related to negatively charged surface states, which are removed upon oxidation of the GaN(0001) surface. This is compared with the Ga2O3(201) single crystal surface, which is found to be inert for the acetaldehyde production. These results offer a toolbox to explore the surface chemistry of nitrides and oxynitrides on an atomic scale and relate their intrinsic activity to systems under ambient atmosphere. [ABSTRACT FROM AUTHOR]

We investigate surface passivation effects of SiNx films deposited by inductive coupled plasma chemical vapor deposition (ICPCVD) and plasma enhanced chemical vapor deposition (PECVD) technologies for InAlAs/InGaAs/InP photo-detectors. It is found that ICPCVD deposited SiNx film effectively reduces the densities of the interface states and slow traps near SiNx/InAlAs interface, which realize the small surface recombination velocity and low surface current for InAlAs/InGaAs/InP photo-detectors. By comparing C-V and XPS results, it is suggested that the trap density reduction by ICPCVD technology could be attributed to the disorder suppression on InAlAs surface due to the high density of SiNx film and less processing energy to the InAlAs surface. [ABSTRACT FROM AUTHOR]

The Al2O3 film formed using an atomic layer deposition (ALD) method with trimethylaluminum as Al precursor and H2O as oxidant at a high temperature (450 °C) effectively passivates the p-type surface conduction (SC) layer specific to a hydrogen-terminated diamond surface, leading to a successful operation of diamond SC field-effect transistors at 400 °C. In order to investigate this excellent passivation effect, we carried out an isotope analysis using D2O instead of H2O in the ALD and found that the Al2O3 film formed at a conventional temperature (100 °C) incorporates 50 times more CH3 groups than the high-temperature film. This CH3 is supposed to dissociate from the film when heated afterwards at a higher temperature (550 °C) and causes peeling patterns on the H-terminated surface. The high-temperature film is free from this problem and has the largest mass density and dielectric constant among those investigated in this study. The isotope analysis also unveiled a relatively active H-exchange reaction between the diamond H-termination and H2O oxidant during the high-temperature ALD, the SC still being kept intact. This dynamic and yet steady H termination is realized by the suppressed oxidation due to the endothermic reaction with H2O. Additionally, we not only observed the kinetic isotope effect in the form of reduced growth rate of D2O-oxidant ALD but found that the mass density and dielectric constant of D2O-grown Al2O3 films are smaller than those of H2O-grown films. This is a new type of isotope effect, which is not caused by the presence of isotopes in the films unlike the traditional isotope effects that originate from the presence of isotopes itself. Hence, the high-temperature ALD is very effective in forming Al2O3 films as a passivation and/or gate-insulation layer of high-temperature-operation diamond SC devices, and the knowledge of the aforementioned new isotope effect will be a basis for further enhancing ALD technologies in general. [ABSTRACT FROM AUTHOR]

Thin layers of Al2O3 are well known for the excellent passivation of p-type c-Si surfaces including highly doped p+ emitters, due to a high density of fixed negative charges. Recent results indicate that Al2O3 can also provide a good passivation of certain phosphorus-diffused n+ c-Si surfaces. In this work, we studied the recombination at Al2O3 passivated n+ surfaces theoretically with device simulations and experimentally for Al2O3 deposited with atomic layer deposition. The simulation results indicate that there is a certain surface doping concentration, where the recombination is maximal due to depletion or weak inversion of the charge carriers at the c-Si/Al2O3 interface. This pronounced maximum was also observed experimentally for n+ surfaces passivated either with Al2O3 single layers or stacks of Al2O3 capped by SiNx, when activated with a low temperature anneal (425 °C). In contrast, for Al2O3/SiNx stacks activated with a short high-temperature firing process (800 °C) a significant lower surface recombination was observed for most n+ diffusion profiles without such a pronounced maximum. Based on experimentally determined interface properties and simulation results, we attribute this superior passivation quality after firing to a better chemical surface passivation, quantified by a lower interface defect density, in combination with a lower density of negative fixed charges. These experimental results reveal that Al2O3/SiNx stacks can provide not only excellent passivation on p+ surfaces but also on n+ surfaces for a wide range of surface doping concentrations when activated with short high-temperature treatments. [ABSTRACT FROM AUTHOR]

Growth of dodecanethiol-encapsulated Au nanoparticles on differently terminated (OH-, H-, or Br-terminated) Si(001) substrates by Langmuir-Blodgett method at a constant monolayer surface pressure and their out-of-plane structural modification with time have been investigated. As the substrates have different gradations in the hydrophilic/hydrophobic nature, three different out-of-plane structures have been formed. On H-terminated Si (hydrophobic surface), a fluctuating monolayer of Au nanoparticles has been formed, whereas on Br- (coexistence of hydrophilic and hydrophobic surfaces) and OH-terminated Si (hydrophilic surfaces), trilayer of Au nanoparicles have been formed, but the top layer coverage is more for the OH-terminated Si. The growth of Au nanoparticles on H-terminated Si is similar to the Frank-van der Marwe mode, whereas on Br- and OH-terminated Si, the growth is similar to the Stranski-Krastanov mode. These three different structures modify with time and finally become a thicker monolayer of high density, and positions of naoparticles within the monolayer become random. AFM images of the films also show that positions of the Au nanoparticles are random. Density of the final layer becomes maximum on OH-terminated Si and minimum on H-terminated Si, whereas it becomes intermediate on Br-terminated Si. Reorganization thus helps to obtain nanostructures of tunable nanoparticle density. [ABSTRACT FROM AUTHOR]

An advanced two-step cleaning process of the Ge(001) surface for nanoscience requirements is presented. First, wet-chemical etching with a variant of the Piranha solution (H2SO4, H2O2, H2O) is used to remove contaminants as well as the native oxide layer. Second, passivation of the surface is achieved by a rapid thermal oxidation step, leading to a homogeneous protective oxide layer. The thickness of the oxide layer is tuned to be thick enough to protect the surface, yet thin enough to be completely removed by thermal treatment in ultra-high vacuum. The application of this recipe results in an outstandingly clean and atomically flat surface, with carbon contamination at the detection limit of x-ray photoelectron spectroscopy. Scanning tunneling microscopy and electron diffraction reveal a long range ordered surface with typical terrace diameters of ∼100 nm, suitable for the growth of atomic-scale nanostructures. [ABSTRACT FROM AUTHOR]

We investigate ambipolar charge transport in organic field-effect transistors (OFETs) with copper-phthalocyanine (CuPc) as active material. It is shown that charge carrier mobilities can be increased by at least one order of magnitude using the long-chain alkane tetratetracontane (TTC) as a passivation layer on top of silicon dioxide. TTC and CuPc films are characterized by atomic force microscopy and x-ray diffraction. TTC forms a highly crystalline layer that passivates electron traps on the SiO2 surface very efficiently and serves as a template for the growth of CuPc films with significantly improved crystallinity. High electron mobilities comparable to the values reported on single crystals are reached. We show that the contact resistance for hole transport as determined by the transmission line method can be reduced considerably by using organic charge-transfer complexes as top contacts in OFETs based on CuPc. [ABSTRACT FROM AUTHOR]

By analyzing photoconductive decay curves, we compared the surface recombination velocities of semi-insulating CdMnTe:In crystals grown by the vertical Bridgman method with or without surface passivation. Sulfur passivation effectively prevents the formation of a conductive Te oxide layer on the CdMnTe surface and reduces the surface recombination velocities by about one third. We demonstrated, from IR observations of the distribution maps of Te precipitates, that their configuration affects the anomalous photoconductive decay curves and the gamma-ray spectrum in some areas of the CdMnTe crystal. Notably, not only the size but also the spatial configuration of the Te precipitates modulates the carrier-transport properties. [ABSTRACT FROM AUTHOR]

This work analyzes heterojunction with intrinsic thin layer (HIT) solar cells using numerical simulations. The differences between the device physics of cells with p- and n-type crystalline silicon (c-Si) wafers are substantial. HIT solar cells with n-type wafers essentially form a n/p/n structure, where tunneling across the junction heterointerfaces is a critical transport mechanism required to attain performance exceeding 20%. For HIT cells with p-type wafers, only tunneling at the back-contact barrier may be important. For p-wafer cells, the hydrogenated amorphous silicon (a-Si:H) between the indium tin oxide (ITO) and crystalline silicon may act as a passivating buffer layer but, otherwise, does not significantly contribute to device performance. For n-wafer cells, the carrier concentration and band alignment of this a-Si:H layer are critical to device performance. [ABSTRACT FROM AUTHOR]

A study of the surface passivation of strained InGaAs using vacuum annealing and silane (SiH4) passivation was reported for the first time. X-ray photoelectron spectroscopy reveals the elimination of As–O bond after vacuum annealing and SiH4 surface passivation. Vacuum annealing eliminated poor quality native oxide on InGaAs surface, while a thin silicon interfacial layer was formed by SiH4 treatment, therefore effectively preventing the InGaAs surface from exposure to an oxidizing ambient during high-k dielectric deposition. Transmission electron micrograph confirmed the existence of a thin oxidized silicon layer between high-k dielectric and InGaAs. By incorporating this surface technology during gate stack formation, TaN/HfAlO/InGaAs metal-oxide-semiconductor capacitors demonstrate superior C-V characteristics with negligible frequency dispersion, small hysteresis, and interface state density as low as (3.5×1011)–(5.0×1011) cm-2 eV-1. [ABSTRACT FROM AUTHOR]

The SiOxFy passivation layer created on structure sidewalls during silicon cryoetching is investigated. This SiOxFy passivation layer formation strongly depends on O2 content, temperature and bias. It is a fragile layer, which mostly disappears when the wafer is warmed up to ambient temperature. A mass spectrometer was used to analyze the desorbed species during the warm-up and using this instrument allowed us to find a large signal increase in SiF3+ between -80 °C and -50 °C. SiF4 etching products can participate in the formation of the passivation layer as it is shown by a series of test experiments. SiF4/O2 plasmas are used to form a thin SiOxFy layer on a cooled silicon wafer. Thickness and optical index of this thin film can be determined by in situ spectroscopic ellipsometry. It is shown that the passivation layer spontaneously desorbs when the silicon wafer temperature increases in good agreement with the mass spectrometry analysis. Two physical mechanisms are proposed to explain the SiOxFy passivation layer buildup involving either the etching products or the SiFx sites created during etching. In both cases, oxygen radicals react at the surface to form the SiOxFy layer. [ABSTRACT FROM AUTHOR]

The kinetics of solid phase epitaxy (SPE) in surface amorphous silicon layers doped with a single arsenic profile have been examined in relation to the generalized Fermi level shifting model of the SPE growth process. The model has been extended to include passivation by hydrogen of the defects responsible for SPE and/or passivation of dopant atoms. A previous study has suggested that the asymmetry between the dopant-enhanced SPE rate and the arsenic concentration profile is due to the infiltration of hydrogen from the surface oxide. Theoretical calculations of the dopant-enhanced SPE rate compare well with experiment if it is assumed that the indiffusing hydrogen passivates some of the SPE defects and/or some of the dopant atoms. [ABSTRACT FROM AUTHOR]

Gallium oxide thin films deposited by electron cyclotron resonance plasma molecular beam epitaxy on GaAs(110) surfaces are reported. Room temperature photoluminescence spectra show an enhancement over as-is surfaces by greater than an order of magnitude for semi-insulating wafers. This enhancement is corroborated by low temperature photoluminescence spectra, showing a reduction in AS[sub Ga], O[sub As], and carbon-related emissions. The bonding configuration at the interface to GaAs was investigated by x-ray photoelectron spectroscopy depth profiling and secondary ion mass spectroscopy: Arsenic oxide related compounds were below the sensitivity limits of the former technique, while carbon (both in the film and in the vicinity of the interface) was below the sensitivity limit of the latter technique. Photoluminescence enhancement is also attributed to hydrogen passivation of EL2 defects, which is found to be stable following deposition at temperatures of 400 °C on semi-insulating and p-type wafers. [ABSTRACT FROM AUTHOR]

We have analyzed the role of the bond densities of a-SiN[sub χ] :H films on the passivation properties at the SiN[sub χ] :H/Si interface. The films are deposited onto silicon wafers by plasma enhanced chemical vapor deposition using a 13.56 MHz direct plasma system and a SiH[sub 4]/N[sub 2]/H[sub 2] gas mixture. Fourier transform infrared spectroscopy measurements are performed in order to obtain the bonding concentration of Si-Si, Si-H, Si-N and N-H. The passivation properties are deduced by lifetime measurements using a microwave-detected photoconductance decay technique. Carrier lifetimes of the SiN[sub χ] :H-passivated silicon wafers of up to 1200 µs correlate to surface recombination velocities, S[sub eff], as low as 4-6 cm/s. This means that the films provide excellent passivation of silicon surfaces, which is necessary for high-efficiency solar cells. The Si-H bond density and the total bond density are considered as measures of the passivation quality. Models for the formation of K[sup +] centers and for the passivation pathways during the plasma deposition are proposed. The addition of a further hydrogen source to the plasma gas (H[sub 2]) leads to a better defect passivation of Si dangling bonds during the deposition. [ABSTRACT FROM AUTHOR]

Electron spin resonance studies have been carried out on the isothermal passivation kinetics in 1 atm molecular H[sub 2] of trivalent Si traps (P[sub b]s;Si[sub 3]≡Si[sup •]) at the interface of thermal (111)/Si/SiO[sub 2] as a function of oxidation temperature T[sub ox] in the range 250-1100°C. Interpretation within the generalized simple thermal (GST) passivation model, based on first-order interaction kinetics, reveals a distinct increase in spread σE[sub f] in the activation energy for passivation E[sub f] with decreasing T[sub ox] (∼3 times in the covered T[sub ox] window), while the other key kinetic parameters (E[sub f], preexponential factor) remain essentially unchanged. The variation in σE[sub f] is ascribed to differently relaxed interfacial stress, affecting the spread in P[sub b], defect morphology. In a second analytic part, the impact of the variation in E[sub f], and correlatively in the activation energy E[sub d] for P[sub b]H dissociation, on P[sub b]-hydrogen interaction kinetics is assessed within the GST-based full interaction scheme, describing parallel competing action of passivation and dissociation. In particular, the passivation behavior in 1 atm H[sub 2] of an initially exhaustively depassivated P[sub b] system, is analyzed exposing, as a major result, that growing spreads σE[sub f], σE[sub d] result in a drastic reduction in passivation efficiency (drop by four orders of magnitude for a threefold increase in σE[sub f]). For σE[sub f]/E[sub f] ... 20%, the P[sub b] system cannot be inactivated beyond the 90% level, incompatible with device quality requirements. Heating time/temperature vs spread conditions for optimum passivation in H[sub 2] have been established, and the technological impact of altering σE[sub f], σE[sub d] is discussed. At film edges and trench corners, which are vulnerable local regions of exces stress, and hence enhanced σE[sub f], &sigma... [ABSTRACT FROM AUTHOR]

This study presents a method for surface passivation using silicon dioxide (SiO[sub 2]). The proposed method has shown great effectiveness on metal-semiconductor barrier height enhancement. A high quality SiO[sub 2] layer is developed via liquid phase deposition, a method which naturally leaves a doping-level fluorine residue in the SiO[sub 2]. The addition of fluorine to enhance the Schottky barrier height (SBH) is first discussed. Experimental results are presented. It is found that this fluorine addition enhances the Schottky barrier height, which allows a larger positive gate bias for enhancement mode metal-semiconductor field-effect transistors, thus permitting the fabrication of digital logic circuits with improved noise margins and relaxed tolerance with regard to device threshold voltage uniformity. The SBH to n-gallium arsenide (GaAS) is found to be approximately 0.7 eV. Finally, the effective barrier height of the metal-insulator-semiconductor structure reache! d 1.03 eV after annealing. The enhancement of SBH has been attributed to the formation of these stable interface layers. A model for fluorine-enhanced SiO[sub 2] SBH enhancement is also presented. © 2001 American Institute of Physics. This study presents a method for surface passivation using silicon dioxide (SiO[sub 2]). The proposed method has shown great effectiveness on metal-semiconductor barrier height enhancement. A high quality SiO[sub 2] layer is developed via liquid phase deposition, a method which naturally leaves a doping-level fluorine residue in the SiO[sub 2]. The addition of fluorine to enhance the Schottky barrier height (SBH) is first discussed. Experimental results are presented. It is found that this fluorine addition enhances the Schottky barrier height, which allows a larger positive gate bias for enhancement mode metal-semiconductor field-effect transistors, thus permitting the fabrication of digital logic circuits with improved noise margins and ! relaxed toler... [ABSTRACT FROM AUTHOR]

Investigates the effects of PH[sub 3]/H[sub 2] plasma passivation of metal-organic chemical vapor deposition grown GaAs on silicon substrate. Capacitance-voltage profiling studies; Auger electron spectroscopy studies; Photoluminescence studies; Schottky diode studies; Solar cell studies.

Analyzes the simultaneous action of passivation and dissociation during thermochemical interaction of trivalent interfacial silicon (Si) traps with molecular hydrogen. Full interaction case; Passivation in hydrogen; Successive passivation treatments in hydrogen; Experimental assessment and verification.

We present the passivation mechanism and the chemistry of an (NH[sub 4])[sub 2]S[sub x] treated (100) InGaP surface using x-ray photoelectron spectroscopy. The native oxide on the as-etched InGaP surface could be further removed by a suitable (NH[sub 4])[sub 2]S[sub x]-treatment process. The measured x-ray photoelectron spectra revealed that the S atoms, in addition to bonding to the elemental sulfur, also bonded with the In and Ga atoms on the (NH[sub 4])[sub 2]S[sub x]-treated InGaP surface. However, the S atoms occupied the phosphorous-related vacancies instead of bonding with the P atoms. A proposed structural model of a sulfur-passivated surface is then presented. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Girish Karnad's Flowers, like Broken Images, is also a monologue that leads us deep into the human unconscious and presents before us the conflict between the inner artistic self and the Dharma or religion. Karnad very clearly presents the flow of human thoughts that reveals the psychic discourse of a person who is deeply rooted in Indian Dharma and who is torn between his inner self and his devotion to religion, God, and family. In this play, instead of delineating the female sexual desire like Naga-Mandala, Karnad focuses on the male desire for carnal love. The Priest obtains great satisfaction in displaying his art while decorating the linga. The linga not only provides the basis for religious devotion to him but also gives him opportunity to realise his artistic freedom. In Flowers the phallic symbol Shiva Linga becomes a medium for attaining salvation. Its benignity and benevolence drive him to the complete renunciation of the worldly desires and strive for attaining Moksha or the Mukti. Total submission to God comes after the arousal of the sense of guilt within the psyche of the individual. The Priest is more burdened with the unexpected and impartial benevolence of God ushered on him than with the sin of adultery and sacrilege. He cannot think himself going unpunished by God. He also cannot exist without realising the freedom of his artistic self. The state of passivity and the sense of guilt compels him to denounce the world and look for the answers to his question in total identification with God. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Thermodynamic parameters of Fe-based glasses hop as c Nb rises from 7 to 10 at.%. • Passive ability of these glasses increases drastically as c Nb rises from 7 to 10 at.%. • Netlike structure in these glasses associated with Fe 23 B 6 cell is verified with simulations. • Netlike structure explains the structure and passivation changes in these glasses. Abstract The atomic structure and corrosion behavior of Fe 87- x B 13 Nb x (x = 0, 7, 10 and 13) metallic glasses were investigated using various experimental techniques and simulations. The netlike (Fe, Nb) 23 B 6 structure units, which took root in the Nb-contained amorphous matrix, emerged after annealing and raised markedly corrosion resistance of as-spun amorphous samples as c Nb > 7 at.%, such as the occurrence of wider passive platform in the potentiodynamic polarization plots and the transformation from the porous holes to stable passive films on corrosion surfaces. [ABSTRACT FROM AUTHOR]

Presents a study which used a film of silicon oxide to passivate gold:germanium:nickel on gallium arsenide during the alloying cycle used to fabricate ohmic contacts. Sample preparation; Results and discussion; Conclusions.

Presents two kinetic models for the hydrogen passivation of polycrystalline silicon. Significance of the introduction of monatomic hydrogen into polysilicon grain boundaries; Description of the models of the passivation process; Apparent surface enhancement of the passivation process.

Studies the use of chlorine-containing oxides in improving the performance of surface passivation of solar cells. Details on the experiment; Discussion of data; Conclusions.

Investigates the influence of hydrogen passivation on the conduction mechanism in the undoped polycrystalline silicon films near room temperature. Prediction of two current components from the temperature dependence of the conductivity in the films; Hopping and conventional thermionic current; Phenomena of resistivity in the undoped films.

Discusses a study which investigated the influence of sulfur passivation on the surface composition of In[sub0.53]Ga[sub0.47]As(001). Background on the sample materials; Methods used; Findings.

Investigates the mechanism of recombination and its effect on cell performance using two-dimensional numerical computer simulations. Extent to which lateral conduction in the rear surface channel contributes to the observed recombination saturation in the cells; Factors contributed to the behavior of passivated emitter and rear locally diffused silicon solar cells; Overview of the electrostatic conditions.

Presents a study that examined the fabrication of conventional and electromagnetically casted multicrystalline silicon solar cells using different passivation schemes. Implementation of plasma-enhanced chemical-vapor-deposition; Information on multicrystalline silicon; Discussion on hydrogen plasma passivation.

Demonstrates a scheme for the surface passivation of GaAs by using electrolytically deposited organic thin molecular layers with terminating reactive sulfur atoms. Methods used to characterize electronic properties of the passivated surface; Advantages of electrodeposition; Details of the synthesis of amphiphilic organic, sodium dioctadecyldithiocarbamate (DODTC); Comparison between the steady-state photoluminescence of DODTC-treated GaAS and an untreated sample.

Presents a study that investigated a back-side passivation film deposited on a-Si:H thin film transistors as a passivation layer. Important characteristic required for a thin-film transistor (TFT) in a liquid crystal display; Fabrication process for the TFT; Effect of the passivation layer on the TFT current-voltage characteristics.

Examines the influence of hydrogen passivation and proton implantation on the electrical properties of AlGaAsSb. Results of isochronal annealing studies in proton implanted samples; Effects of hydrogen passivation; Observations on the thermal stability of hydrogen.

Presents a study that analyzed the modification of interfacial properties of n-gallium arsenide semiconductor with vacuum-evaporated polyphenylene sulphide. Methodology; Measurement of the surface recombination velocity on the gallium arsenide surface; Examination of the passivation effects of propylene sulphide.

Examines the surface chemistry of gallium arsenide (GaAs) passivated wih P[sub2]S[sub5] solutions modified with sulfur and other sulfides. Reason for the interest in surface passivation of GaAs; Measurement of the degree of passivity achieved; Collection of room-temperature photoluminescence data.

Discusses a study which examined the passivation of superconducting YBa[sub2]Cu[sub3]O[sub7-x] thin films by a wet fluoride vapor method. Techniques to prevent degradation of YBa[sub2]Cu[sub3]O[sub7-x] during exposure to air; Measurement of the film resistance during water immersion; Reaction products on the superconducting YBa[sub2]Cu[sub3]O[sub7-x] thin-film surface due to exposure to moist air.

Presents a study that investigated hydrogen passivation of chalcogen impurities in silicon diodes using deep-level transient spectroscopy. Analysis of the passivation of the sulfur-related center; Evaluation of the reactivation of chalcogen double donors; Examination of the chalcogen-related donor defects.

Reports a surface passivation study using passivated diodes on Schottky-barrier diodes formed by gold and aluminum contacts. Information on the reverse leakage current barrier height of the passivated diodes; Examination of various approaches to reduce surface state density.

Presents a study that investigated the passivation of an amorphous nickel-14 chromium-17 phosphorus-0.5 carbon alloy thin films. Methodology; Examination of the surface morphology of the samples; Analysis of the optical and electrical characteristics of the samples.

Analyzes hydrogen passivation of acceptors in p-indium phosphorous (InP). Background on the problem of hydrogenation of InP; Investigation of the shallow receptors in InP; Comparison of the plasma exposures of gallium arsenide and InP passivation; Results and discussion.

Presents a comparative study of methods for low-temperature preparation of clean surfaces needed to fully enable fabrication processes in silicon. Comparison of silicon surfaces for residue and chemical passivation following hydrogen termination; Characterization of surface residue using various spectroscopic techniques; Evaluation of passivation.

Presents results on the passivation of mercury cadmium telluride with thin films of cadmium sulphide grown anodically from non-aqueous polysulphide electrolytes. Capacitance-voltage measurements on metal-insulator-conductor device structures; Surface spectroscopies carried out at 170 Kelvin; Interdiffusion of zinc into the interface.

Demonstrates the effectiveness of the implantation of hydrogen into cadmium telluride in passivating deep levels in the bulk and surfare shallow defect levels in Si[sup18,19] and GaAs[sup10,11]. Evaluation of the influence of ion-induced damage during implantation; Details of experimental procedures; Passivation of deep defect levels.

Presents information on a study which introduced copper to passivate the defects in silicon materials and improve the efficiencies of solar cells. Examples of silicon materials that have a number of defects which degrade electrical properties; Methodology of the study; Results and discussion.

The electron density and physical stress at the thermally oxidized SiC/SiO2 interface, and their change with nitrogen incorporation, were observed using x-ray reflectivity, Raman scattering, and in-situ stress measurement. There is no evidence for residual carbon species at the SiO2/SiC. Instead, a ∼1 nm thick low electron density layer is formed at this interface, consistent with interfacial suboxides (SiOx, 0.3 < x < 2), along with high interfacial stress. Nitrogen passivation, a known process to improve the interface state density and electronic properties, eliminates the low density component and simultaneously releases the interface stress. On the basis of these findings, a chemical interaction model is proposed to explain the effect of the nitrogen in terms of both stress reduction and elemental control of the dielectric/SiC interface, resulting in a higher quality gate stack on SiC. [ABSTRACT FROM AUTHOR]

Abstract In this work, the passivation behavior of Nb in acid fluoride-containing solutions with pH of 4, 5 and 6 was investigated. Both electrochemical measurements and surface characterization were systematically used to explore the pH effect on the electrochemical stability of Nb in aggressive oral cavity environment. The point defect model (PDM) and surface charge approach (SCA) were used as theoretical basis to analyze the passive film growth and dissolution kinetics. As the pH value decreases, the passive film becomes more reactive and suffers more severe dissolution, leading to higher point defect density across the passive film and more pronounced surface charge behavior at the film/solution interface. Furthermore, the surface becomes rougher and the passive film is thinner with less amount of suboxide as the solution is more acid. Since high electrochemical stability of the passive films is desirable for Nb implants, the results from this work shed insight into the use of fluoride-containing prophylactic substances. Highlights • pH dependent passivation behavior of Nb in acid F−‒containing is examined. • The PDM and SCA are used to analyze the film growth and dissolution kinetics. • The pH effect is quantitatively characterized with kinetics parameters. • The decrease of pH promotes the dissolution reactivity of the passive film. • The decrease of pH leads to a rougher and thinner passive film with less suboxide. [ABSTRACT FROM AUTHOR]

This paper reviews the most recent available literature relating to the electrochemical techniques and test procedures employed to assess tribocorrosion behaviour of passive materials. Over the last few decades, interest in tribocorrosion studies has notably increased, and several electrochemical techniques have been adapted to be applied on tribocorrosion research. Until 2016, the only existing standard to study tribocorrosion and to determine the synergism between wear and corrosion was the ASTM G119. In 2016, the UNE 112086 standard was developed, based on a test protocol suggested by several authors to address the drawbacks of the ASTM G119 standard. Current knowledge on tribocorrosion has been acquired by combining different electrochemical techniques. This work compiles different test procedures and a combination of electrochemical techniques used by noteworthy researchers to assess tribocorrosion behaviour of passive materials. A brief insight is also provided into the electrochemical techniques and studies made by tribocorrosion researchers. [ABSTRACT FROM AUTHOR]

Aging of passive film formed on UNS N08031 was investigated as a function of passivation time in Green-Death solution at 40°C. The specimen surface was in a stable passive state in the solution. The passive current density increased with an increase in the passivation potential. Electrochemical impedance spectroscopy and Mott-Schottky (M-S) analyses revealed that a more defective n-type semiconductive passive film formed as the potential increased while the film became stable as the defects in the film decreased at potential lower than 1.0 VSSE. The increase of the applied potential and the polarisation time are likely reasons for the change in passive film stability. [ABSTRACT FROM AUTHOR]

The mechanism of passivity breakdown on Cu 2 O films was studied. The thickness and components of the film were estimated by EIS, AES and XPS analyses. The structural relaxations, energies, electronic properties and diffusion coefficients were calculated by first-principles calculations. Both the experimental and calculated results demonstrate that the film thinning is due to the adsorption of Cl − on the surface instead of a penetration process. The inner point defects facilitate the adsorption of Cl − , and the introduction of Cl − , in turn, increases the transport rate of point defects. A theoretical model was proposed, which is also applicable to local breakdown. [ABSTRACT FROM AUTHOR]