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The previously proposed technique of microwave volt–impedance spectroscopy of semiconductors has been experimentally verified. The technique allows one to determine the local values of electrical parameters of a semiconductor. The investigations have been carried out on a homogeneous single-crystal GaAs wafer with a system of concentric antennas formed on the top of it. The resolution is determined by the antenna central disk diameter, which has been 12, 27, and 57 μm. A dc bias voltage of 0 V ≤ U ≤ 5 V has been applied between antenna contact pads. The complex Z(f, U) impedance spectrum of each antenna has been measured on a Cascade Microtech probe station in the frequency range of f = 0.1–10 GHz. The electrical characteristics of the semiconductor have been determined from the Z(f, U) spectra by solving the inverse problem. The n-type of the semiconductor has been established, and the contact potential difference at the interface with a metal has been determined. The local values of electron density, mobility and electrical conductivity have been found have been found. The four-point probe Hall effect measurements of the surface-averaged values of the same parameters have shown good agreement of the results for the investigated homogeneous wafer.

Using the methods of optically stimulated electron emission (OSEE) and ambient pressure photoemission spectroscopy (APS), the energy characteristics of carbyne-containing films on copper and silicon substrates have been studied. The average contact potential difference and the work function were determined, and the positions of the Fermi level for carbyne-containing films of various thicknesses were calculated. It was found that the electrons work function and the position of the Fermi level of the studied film samples do not depend on the film thickness and the type of substrate. The information content of the OSEE and APS methods for evaluating the quality of carbon coatings on substrates is shown.

The chemical states and changes in the work function of a heterogeneous multilevel film have been determined during the adsorption of cesium at 295 K on a cylindrical gas-phase polycrystalline tungsten coating (30 μm) of Nb–1%Zr alloy with a minimum concentration of residual oxygen using low-energy threshold electron spectroscopy and contact potential difference methods. The chemical states and the change in the work function of this film have been found during successive heating up to 1875 K.

Using low-energy (0–25 eV) threshold electron spectroscopy and contact potential difference in vacuum not worse than 2 × 10–8 Pa, oxygen films obtained at 295, 325–1425 (in steps of 50), and 1575 K, including in subsequent heating from the adsorption temperature to 1925 ± 50 K, on ​​the cylindrical surface of a gas-phase tungsten coating 30 μm thick on NbC-1 alloy (Nb – 1% Zr), used as a collector material for thermal emission in space-borne nuclear power plants, have been studied.

Analysis of the contact-barrier height taking into account the distribution of surface states along coordinate x perpendicular to the insulator–semiconductor interface is performed for metal–semiconductor contacts with a dielectric gap. It is shown that taking into account the spatial dependence of the density of surface states at rather high semiconductor doping levels leads to a substantial decrease in the barrier height, which promotes the realization of ohmic contacts. It is established that the smaller the metal–semiconductor contact potential difference ϕ ms is, the stronger the effect of barrier-height lowering. If ϕ ms is negative, this effect can lead to potential sign reversal, i.e., to the realization of an enrichment layer in the space-charge region of the semiconductor even at a high density of surface states. This in turn promotes the manifestation of an anomalous dependence of the contact resistivity on temperature; the resistivity increases with an increase in temperature.

The types of cells and methods of electrochemical reduction of graphene oxide films were described. The possibility of creating ultrathin membrane–electrode assemblies of supercapacitor cells was demonstrated. The peculiarities of the electrochemical behavior of films of different thicknesses that contact with carbon and metal current collectors were shown. The limiting charge (1500–2000 C/g) for complete electrochemical reduction of graphene oxide was determined. Possible mechanisms of proton conductivity along the basal faces of graphene oxide flakes were proposed. The nature of the current collector was shown to affect the electron–hole conductivity of graphene oxide films and the observed contact potential difference.

The transformations in nanosized Ni–MoO3 systems were studied by optical spectroscopy, microscopy, and gravimetry depending on the thickness of the Ni (d = 1–40 nm) and MoO3 (d = 3–50 nm) films, temperature (473–773 K), and thermal treatment time. The contact potential difference was measured for Ni and MoO3 films; photovoltage, for Ni–MoO3 systems. An energy band diagram of the Ni–MoO3 systems was constructed. A model of the thermal transformation of MoO3 films in Ni–MoO3 systems was suggested, which involves a redistribution of equilibrium charge carriers at the contact, formation of a [(Vа)++е] center during the preparation of the MoO3 film, the transformation of this center into an [е(Vа)++е] center during the formation of Ni–MoO3 systems, and the thermal transition of an electron to the level of the [(Vа)++е] center to form an [е(Vа)++е] center.

Conversion of copper into copper nitride at T = 293 K in copper nanofilms of thickness d = 2–13 nm has been studied by optical spectroscopy, optical microscopy, and gravimetry. Kinetic curves for the degree of conversion in the films are adequately represented by a linear, inverse logarithmic, cubic, or logarithmic rate law, depending on copper film thickness. We have measured the contact potential difference across the Cu and Cu3N films and the photovoltage in the Cu–Cu3N system, and constructed the energy band diagram of the Cu–Cu3N films. A model has been proposed for the chemical transformations in the Cu films, which includes ammonia adsorption, an equilibrium carrier diffusion and redistribution in the Cu–Cu3N interfacial field, and copper nitride formation.

Transformations in nanosized manganese films are studied by means of optical spectroscopy, microscopy, and gravimetry at different film thicknesses (d = 4–108 nm) and temperatures of heat treatment (T = 373–673 K). It is found that the kinetic curves of conversion are satisfactorily described in the terms of linear, inverse logarithmic, cubic, and logarithmic laws. The contact potential difference is measured for Mn and MnO films, and photo EMF is measured for Mn–MnO systems. An energy band diagram is constructed for Mn–MnO systems. A model for the thermal transformation of Mn films is proposed that includes stages of oxygen adsorption, the redistribution of charge carriers in the contact field of Mn–MnO, and manganese(II) oxide formation.

The catalytic decomposition of ammonia on (C2B10H4)n organoboron nanoparticles deposited onto SiO2, Al2O3, and graphite substrates at 750 K and 10–6 Torr is studied. The effect of the substrate material on the rate of NH3 decomposition is established. It is demonstrated that the replacement of SiO2 by Al2O3 or graphite increases the decomposition rate 1.9- and 2.3-fold, respectively. The catalytic activity of the nanoparticles increases with the contact potential difference between the nanoparticles and the substrate. The potential difference between the nanoparticles particles and the SiO2, Al2O3 and graphite substrates are found to be–0.5,–0.2, and 0.0 V, respectively.

Transformations in nickel nanofilms as a function of thickness (d = 3–60 nm) and temperature of heat treatment (T = 373–873 K) are studied via optical spectroscopy, microscopy, and gravimetry. It is found that, depending on the thickness of nickel films and temperature of heat treatment, the kinetic curves of the degree of transformation are satisfactorily described in terms of the linear, inverse logarithmic, cubic, and logarithmic laws. The contact potential difference for Ni and NiO films and the photovoltage for Ni-NiO systems are measured. An energy band diagram for Ni-NiO systems is constructed. A model of the thermal transformation of Ni films, including the stages of oxygen adsorption, charge carrier redistribution in a Ni-NiO contact field, and the formation of nickel(II) oxide, is proposed.

Transformations of gallium nanofilms have been studied by optical spectroscopy, optical microscopy, and gravimetry at film thicknesses d = 2–74 nm and heat treatment temperatures T = 423–873 K. Kinetic curves of the degree of conversion in the films are adequately represented by a linear, inverse logarithmic, parabolic, or logarithmic rate law. We have measured the contact potential difference across the Ga and Ga2O3 films and the photovoltage in the Ga-Ga2O3 system and constructed the energy band diagram of the Ga-Ga2O3 films. A model has been proposed for the thermal transformation of Ga films which includes oxygen adsorption, carrier redistribution in the Ga-Ga2O3 interfacial field, and gallium(III) oxide formation.

Transformations of cobalt nanofilms have been studied by optical spectroscopy, optical microscopy, and gravimetry at film thicknesses d = 2–35 nm and heat treatment temperatures T = 473–873 K. Kinetic curves of the degree of conversion in the films are adequately represented by a linear, inverse logarithmic, cubic, or logarithmic rate law. We have measured the contact potential difference across the Co and Co2O3 films and the photovoltage across the interface and constructed the energy band diagram of the Co and Co2O3 films. A model has been proposed for the thermal transformation of Co films which includes oxygen adsorption, carrier redistribution in the Co-Co2O3 interfacial field, and cobalt(III) oxide formation.

The transformations in nanosized chromium layers at different layer thicknesses (d = 14–154 nm) and thermal treatment temperatures (T = 673–873 K) were studied by optical spectroscopy, microscopy, and gravimetry. The kinetic curves of conversion at different chromium film thicknesses and treatment temperatures are well approximated by the linear, inverse logarithmic, cubic, and logarithmic functions. The contact potential difference for Cr and Cr2O3 films and photo-emf for Cr-Cr2O3 systems were measured. An energy band diagram of Cr-Cr2O3 systems was constructed. A model of thermal transformation was constructed for Cr films that included the stages of oxygen adsorption, charge carrier redistribution in the contact field of Cr-Cr2O3, and chromium(III) oxide formation.

The principle of quasi-equilibrium in the study of the structures that contain semiconductors and insulators, in particular, dielectric films in the metal-insulator-semiconductor (MIS) structures is discussed. A possibility of the simultaneous measurements of the averaged convection currents in an insulator and the current flows through the semiconductor-insulator interface in the MIS structures is considered. The methods for the measurement of the concentration of mobile ions in a dielectric film are analyzed.

Exposure to light of intensity I =1.12 × 1015 to 7.0 × 1015 photons/(cm2 s) at λ = 360 nm and T = 293 K produces significant changes in the absorption and reflection spectra and weight of indium films 1 to 32 nm in thickness. Kinetic curves for the photochemical transformation of the indium films are adequately represented by a linear, inverse logarithmic, parabolic, or logarithmic rate law. We have measured the contact potential difference across the In and In2O3 films and the photovoltage in the In-In2O3 system. A model has been proposed which includes the generation and redistribution of nonequilibrium charge carriers in the In-In2O3 interfacial field, oxygen adsorption, In3+ diffusion, and In2O3 formation.

Optical spectroscopy, gravimetric analysis, and microscopy studies show that irradiating bismuth films (d = 3–55 nm) with light (λ = 360 nm and I = 1.8 × 1015–7.0 × 1015 quantum cm−2 s−1) leads to major changes in their absorption and reflectance spectra and in film mass. The kinetic curves of the degree of photochemical transformation of bismuth films are shown to obey linear, inverse logarithmic, cubic, and logarithmic laws. The contact potential difference (CPD) of Bi and Bi2O3 films and the photo-electromotive force (emf) of Bi-Bi2O3 systems are measured. An energy band diagram of Bi-Bi2O3 systems is constructed. A model that includes the stages of generation, recombination, and redistribution of nonequilibrium charge carriers in the contact field of a Bi-Bi2O3 system, oxygen adsorption, diffusion of cation vacancies, and Bi2O3 formation is proposed.

Transformations in Bi-MoO3 nanosized systems are studied by optical spectroscopy, microscopy, and gravimetry. The contact potential difference for the Bi and MoO3 films and the photovoltage of the Bi-MoO3 systems are measured, depending on the thickness of Bi (d = 3–92 nm) and MoO3 films (d = 5–40 nm) and the temperature (373–673 K) and time of heat treatment. An energy band diagram of the Bi-MoO3 systems is constructed. A model of the thermal transformation of MoO3 films in Bi-MoO3 systems is proposed that involves the redistribution of equilibrium charge carriers on a contact, the formation of a ([(Va)++e]) center during the preparation of a MoO3 film, the transformation of this center into a ([e(Va)++e]) center during the formation of Bi-MoO3 systems, and the thermal transition of an electron to the level of a ([(Va)++e]) center to form a ([e(Va)++e]) center.

Transformations in In-MoO3 nanosystems have been studied by optical spectroscopy, micros-copy, and gravimetry in relation to the thickness of the In and MoO3 layers and heat-treatment temperature and time. We have measured the contact potential difference across the In and MoO3 films and the photo-voltage in the In-MoO3 system and constructed the energy band diagram of the In-MoO3 system. A model has been proposed for the thermal transformation of the MoO3 films in In-MoO3 bilayers, which involves a redistribution of equilibrium charge carriers at the contact, the formation of a [(Va)++e] center during the preparation of the MoO3 film, transformation of the center into a [e(Va)++e] center during the fabrication of the In-MoO3 bilayer, and thermal ionization of the [e(Va)++e] center.

The electron work function in alloys and compounds containing alkali metals, which are of interest for the designing of new photocathode materials and further development of the theory of electron emission, is studied. It is shown that a number of applied and theoretical issues in this field are poorly understood. These are the temperature and concentration dependences of the electron work function in binary metallic systems, the surface activity of components that are inactive in alloys with alkali metals, and some others.

Anisotype surface-barrier n-Cd0.5Zn0.5O/p-CdTe heterojunctions are fabricated by the high-frequency sputtering of a Cd0.5Zn0.5O alloy film onto a freshly cleaved single-crystal CdTe surface. The main electrical properties of the heterojunctions are studied and the dominant mechanisms of charge transport are established, namely, the multistage tunnel-recombination mechanism under forward bias, Frenkel-Pool emission, and tunneling under forward bias. The influence of the surface electrically active states at the heterojunction interface is analyzed and their surface concentration is evaluated: Nss ∼ 1014 cm−2.

The method of contact potential difference is applied to determine the electron work function of ingots and pellets (compacted powder) of LaNi5 − x T x (T = Al, Cu, Fe; x = 0, 1) intermetallics at 293 K. A correlation is revealed between the electron work function and the heats of formation of the intermetallics and their hydrides.

Transformations in indium nanolayers have been studied by optical spectroscopy, microscopy, and gravimetry in relation to the thickness of the layers (2–147 nm) and heat treatment temperature (473–873 K) and time (0–120 min). The kinetic curves for the degree of conversion are adequately described by a linear, inverse logarithmic, parabolic, or logarithmic law, depending on the thickness of the indium film and heat treatment temperature. We have measured the contact potential difference across the In and In2O3 films and the photovoltage in the In-In2O3 system. The results have been used to derive the energy band diagram of the In-In2O3 system. A model has been proposed for the thermal transformation of indium films, which involves oxygen adsorption steps, charge carrier redistribution in the In-In2O3 interfacial field (positive on the In2O3 side), and In2O3 formation.

Transformations in a nanosized bismuth layer are studied by means of optical spectroscopy, microscopy, and gravimetry, depending on the thickness (d = 3–120 nm), thermal treatment temperature (T = 373–673 K) and time (τ] = 0.05–2500 min). It is established that, depending on the initial thickness of the bismuth films and the thermal treatment temperature, the kinetic curves of the degree of transformation are satisfactorily described within linear, inverse logarithmic, cubic, and logarithmic laws. The contact potential difference for the Bi, Bi2O3 films and the photo-electromotive force for the Bi-Bi2O3 systems is measured. An energy-band diagram for the Bi-Bi2O3 systems is constructed. A model for the thermal transformation of Bi films that includes the stage of oxygen adsorption, the redistribution of charge carriers in the Bi-Bi2O3 contact field, and the formation of bismuth(III) oxide is proposed.

The interaction of ytterbium nanofilms evaporated on tungsten substrates with oxygen has been studied by Auger electron spectroscopy, thermal desorption spectroscopy, and contact potential difference measurements. It has been shown that at room temperature, no oxide is formed in the above interaction. In place of the oxide, a chemisorbed layer of nondissociated O2 molecules is formed on the surface of the ytterbium nanofilms. This layer modifies the ytterbium. This modification transforms ytterbium from the divalent state into the trivalent state.

The problems of the electric field action on carbon nanotubes (CNTs) during their growth and under the electron field emission conditions are considered. The relations determining the growth rate of an extended structure under the action of the electric field are established. The relation connecting the angle of orientation of a CNT inclined to the substrate surface and the applied electric field is used for computing current-voltage characteristics of the cathode consisting of inclined CNTs. The degree of deviation of these characteristics from the Fowler-Nordheim classic dependence is determined, on the one hand, by the parameters characterizing the CNT spread over the angles of inclination and, on the other hand, by the value of the Young modulus characterizing the bending stiffness of a nanotube. It is shown that in zero external electric field, a certain effect on the CNT orientation can be produced by the CNT potential relative to the substrate, which is due to the effect of the contact potential difference.

Transformations in Pb-WO3 nanodimensional systems are investigated in dependence on the thickness of the Pb and WO3 films, temperature, and thermal treatment duration by means of optical spectroscopy, microscopy, and gravimetry. The contact potential difference for Pb and WO3 films and the photoelectric power of Pb-WO3 systems is measured. A diagram of the energy bands of Pb-WO3 systems is constructed. A model of thermal transformation for the WO3 films in Pb-WO3 systems is suggested. The model involves the redistribution of equilibrium charge carriers on the contact, formation of the ([(Va)++e]) center during the preparation of a WO3 film, its transformation into a ([e(Va)++e]) center during the formation of the Pb-WO3 systems, and thermal ionization of the ([e(Va)++e]) center.

The real and chemical thermodynamic characteristics of the resolvation of Cu2+ ions in water-methanol mixtures were determined by the Kenrick method at 298.15 K from the experimental compensating voltages of the Volta circuits and the surface potential at the interface between the nonaqueous solvent and the gas phase \(\Delta \chi _{H_2 O}^{MeOH}\). The assumption about the constancy of \(\Delta \chi _{H_2 O}^{MeOH}\) starting from X = 0.1 of methanol in the mixture was confirmed by the Harkins method.

The effect of the electric potential of the surface of technically pure A85 aluminum on stress relaxation is studied. It is found that upon a change in the electric potential of the sample from a stabilized power supply, the average relaxation rate increases, and the activation volume decreases upon an increase in the absolute value of the electric potential. If a metal with a work function differing from that of aluminum is connected to the sample, the dependences of the average relaxation rate and activation volume on the contact potential difference are nonmonotonic. The results of experiments are discussed.

A model of the potential distribution in voltage terminating structures (VTSs) with floating p+-n junction rings in silicon radiation detectors is proposed. The model is based on experimental current-voltage characteristic of interring gaps, measured for detectors based on high-resistivity silicon with resistivities from 1 to 25 kΩ cm. The physical basis of the model is the injection principle of current flow through VTS interring gaps, which becomes possible at a certain electric field distribution in space charge regions of p+-n junctions of the sensitive contact and rings. It is shown that the injection current flow is a universal operation principle of the VTS with floating rings, which leads to rigid stabilization of potentials of individual rings. As a result, it becomes possible to divide the potential irrespective of the semiconductor material resistivity.

It is shown that the Berglund method for determining the metal-insulator-semiconductor surface potential relaxation as the structure voltage changes is valid only in the absence of convective currents in the insulator. A method for determining the potential relaxation in the presence of convective currents is suggested. The currents induced in the structure due to changes in the contact potential difference during temperature variations are also considered.

The electron work function in cast samples and cylindrical compacts of YNi3 − xTx (T = Cu, Fe, Mn; x = 0, 0.5) intermetallics is determined using the contact potential difference method. A correlation is found between the electron work function and the electronegativity of elements substituting Ni in the YNi3 structure.

A conducting organic polymer is visualized on a laser photoelectron projection microscope, which is based on Letokhov’s concept and has a nanometer spatial resolution. Photoelectron images of polyaniline (which is the most promising representative of conducting polymers) with a magnification of ∼105 have been obtained when a 100-nm quartz capillary coated with a film of this material was irradiated by femtosecond laser pulses. The projection photoelectron method using 400- and 800-nm laser radiation has made it possible to directly reveal the existence of the redox heterogeneity of the organic polymer, which is due to the contact of the sections of polyaniline with different oxidation degrees and strongly affects the electric conductivity of the sample.

The volta potential difference method at 298.15 K was used to determine the real primary medium effect for magnesium, calcium, cadmium, and copper ions, and also the real Gibbs transfer energy of these ions from water into a mixed water ethanol (EtOH) solution. The surface potential value at the nonaqueous solution/gas phase interface \( \Delta \chi _{H_2 O}^{EtOH} \) was obtained. With account for this value, chemical thermodynamic characteristics of the studied ions in the water-ethanol solvent were calculated and the effect of composition and nature of the mixed solvent on the values obtained was analyzed. The dependence of variation in the thermodynamic characteristics of cation resolvation was established on their crystallographic radius that corresponds to the following sequence: Ca2+ < Cd2+ < Cu2+ < Mg2+.

The effect of an electric potential φ ≤ 5 V on the creep and microhardness of a number of metals and alloys is considered. The creep rate and microhardness are shown to vary as an excess electric charge is induced on a surface by applying a potential from a voltage source or due to a contact potential difference. These effects are nonmonotonic and irreversible, and their nature is discussed.

The effect of electric potential on the microindentation resistance is investigated experimentally for aluminum and zirconium samples. The effects of the electric potential proper applied to a sample and of the potential arising due to contact potential difference between metals with different electron work functions are compared. A qualitative equivalence of these two types of electrical action is revealed. A possibility of a significant (over 10%) change in the metal microhardness due to the above nentioned actions is established.

Investigations of the potential of the free surface of gallium arsenide and of the surface coated (locally or entirely) by thin layers of gold or platinum have been carried out using atomic force microscopy in the Kelvin mode. The results obtained show that the potential measured in the metal-probe system corresponds as a whole to its contact potential difference (CPD). CPD values measured for the gallium arsenide-probe system depend on the type of processing that may be related to the influence of the processing on the electron affinity of a semiconductor. The lateral size effect consisting in the presence of a significant (about 10 µm) transition zone (aureole) between the metal contact and the GaAs free surface has been found. In this region the potential varies gradually between values of the potential of the metal contact and the free surface of the semiconductor. The potential of a contact depends on its dimensions (diameter and thickness) and on the substrate material’s (GaAs) properties.

A new approach to investigating the leakage of nonequilibrium holes and electrons from the active region of a semiconductor laser diode is proposed. According to this, the scanning Kelvin probe force microscopy is used to measure averaged local changes in the contact potential difference on the surface of laser mirrors of a device operating at a pulsed bias voltage. It is shown that the measured signal level is determined by the degree of charge exchange between the slow surface states and nonequilibrium minority carriers, the concentration of which is directly related to the leakage current.

The effect of the electric potential on the microhardness of aluminum, zirconium, and ferrosilicon was studied experimentally. The effect of the proper electric potential applied to a sample is compared with the effect of the potential induced by the contact potential difference upon contact with metals with a different electron work function. These two types of electrical action are revealed to be qualitatively equivalent to each other. It is established that these effects can markedly (up to 15%) change the microhardness of the metals.

The gravimetric and optical spectroscopic methods reveals that light irradiation with λ = 300–750 nm and intensity I = 6.9 × 1014–1.1 × 1016 quanta cm−2 s−1 for τ = 1–160 min in atmospheric conditions significantly changes the absorption and reflection spectra and mass of aluminum films (d = 2–200 nm). The kinetic curves of the degree of conversion versus aluminum film thickness are satisfactorily described in the inverse logarithmic and parabolic terms. The contact potential difference is measured for Al and Al2O3 films along with the photo-EMF of Al-Al2O3 systems. The suggested model includes the stages of generation and redistribution of nonequilibrium charge carriers in the contact field of Al-Al2O3 systems, oxygen adsorption, Al3+ diffusion, and Al2O3 formation.

The electron work function, contact potential difference, and surface tension of elastically deformed faces of metal with an insulating coating have been calculated within the Kohn-Sham method. The calculations demonstrate the opposite deformation dependences of the electron work function and contact potential difference. An insulating coating leads to a negative change in the work function and a positive change in the contact potential difference. It is shown that the measurements of the contact potential difference of a deformed face by the Kelvin method give only the change in the value of the one-electron effective potential on the plane of a virtual image behind the surface rather than the value of the electron work function. The calculated values of the electron work function and surface tension for Al, Au, Cu, and Zn are in agreement with the results of experiments for polycrystals and first-principles calculations.

The surface tension, electron work function, and contact potential difference of elastically deformed faces of Al, Au, Cu, and Zn crystals are calculated in the stable jelly model with the help of the self- consistent Kohn-Sham method. Calculations demonstrate a decrease (increase) in the electron work function and an increase (decrease) in the contact potential difference upon axial extension (compression) of the metal crystal surface. Dielectric coating leads to a negative (positive) change in the work function (contact potential difference). It is shown that the measurement of the contact potential difference of a deformed face by the Kelvin method corresponds to a change not in the electron work function, but in the value of one-electron effec- tive potential on the virtual image plane behind the surface. The calculated values are in conformity with exper- imental results for polycrystals and the results of ab initio calculations.

The baroelectric emf of an Ag+-conducting solid-state cell Ag-Ag4RbI5-Ag is investigated. It is shown that, when one of the electrodes of the ion-conducting solid-state cell is loaded, the baroelectric emf of the cell is equal to the sum of the electronic and ionic baroelectric contact potential differences. The electronic (ionic) baroelectric contact potential difference is determined by the work done by the load on changing the electrode volume upon the removal of one electron (ion). The elementary processes responsible for the change in the volume due to the removal of a particle are discussed.

The effect of the thickness of a buffer layer of intrinsic GaSe oxide on the electrical, photoelectric, and emissive properties of ITO-GaSe heterojunctions is studied. It is established that the introduction of a Ga2O3 layer with thickness as large as 5–6 nm into the ITO-GaSe heterojunction results in a change in the current-flow mechanisms in the structure, an increase in the open-circuit voltage V oc by more than twofold (in this case, the situation where the V oc exceeds appreciably the contact potential difference is realized), an increase in the electroluminescence intensity by more than an order of magnitude, and an increase in the efficiency of photoconversion by more than two times compared to samples where the Ga2O3 layer was not grown intentionally.

The formation and properties of the Yb-Si(100) thin-film system were studied by high-resolution photoelectron spectroscopy with synchrotron radiation, Auger electron spectroscopy, the contact potential difference technique, and low-energy electron diffraction measurements over a wide range of coverages and at different temperatures. It was established that the formation of the Yb-Si(100) system prepared by solid-phase epitaxy occurs through a mechanism close to the Stranski-Krastanow mechanism. It was shown that, at submonolayer coverages, it is primarily these two-dimensional (2D) 2 × 3 and 2 × 6 structures that are formed, while at higher coverages a three-dimensional Yb silicide film grows. Data on the morphology and phase composition of the silicide film and on the electronic state of the Si atoms and the valence state of the Yb atoms in the silicide and the 2D structures, as well as on the atomic structure of these films, were obtained. The components of the Si 2p spectra were studied for different coverages. The relation between the shape of these spectra obtained for multilayer Yb silicide films and their phase composition was revealed.

Standard thermodynamic parameters characterizing the resolvation of the Cu2+ ions and the surface potential at the gas-phase/acetone interface, ΔχMe2CO, are determined on the basis of the results of measuring compensating voltages of the Volta circuits by the Kenrick method at 298.15 K and the value of the surface potential at the nonaqueous-solvent/gas phase interface, ΔχH2OS, which was obtained earlier. A comparison of thermodynamic parameters characterizing the resolvation of the copper ions with similar quantities for the calcium and cadmium ions is performed. Specific features pertaining to the solvation of copper ions in a mixed water-acetone solvent are elucidated and the effect of the composition and nature of the mixed solvent on the quantities obtained is determined. A dependence of variations in the thermodynamic parameters characterizing the resolvation of cations on their charge and crystallographic radius is established. The dependence corresponds to the series K+, Ca2+, Cd2+, Cu2+.

Compared to PbN6(Ab), the PbN6(Ab)-Cd system was found to be characterized by a low photolysis rate within the region of intrinsic absorption of PbN6(Ab) and, at the same time, by a broader range of spectral sensitivity of PbN6(Ab), up to 510 nm. Preliminary irradiation by 380-nm light resulted in an increase in the photolysis rate. The photolysis rate constants for the PbN6(Ab)-Cd system were determined. An analysis of the voltammetric characteristics, photocurrent, and contact potential difference made it possible to develop a model of the photolysis of the PbN6(Ab)-Cd system, including the stages of generation, recombination, redistribution of nonequilibrium charge carriers in the contact field, the photoemission of electrons, formation of the photolysis products, and genesis of the PbN6(Ab)-Pb(photolysis product)-Cd system. It was demonstrated that the diffusion of anionic vacancies to neutral Pbn0 sites is the limiting stage of the photolysis of the PbN6(Ab)-Cd system.

We present a method for investigating the charge state of the semiconductor-insulator interface using the measurements of the contact potential difference between the surface of the insulator film and a vibrating probe. In this method, the surface electrostatic potential is changed through charge variation at the outer surface of the insulator. The charge value is determined by the time of the structure exposure to a corona discharge. The method is applied for investigating the effect of exposure of a silicon-silicon dioxide system to radiation and pulse magnetic fields.

Silicide formation in thin films produced by depositing Eu atoms on the Si(111) surface is studied using LEED, Auger electron spectroscopy, contact potential difference, and isothermal thermal-desorption spectroscopy. It is shown that if Eu is deposited on a substrate at room temperature, the growing film is disordered and consists of almost pure Eu. At high temperatures (T≥500 K), the Eu-Si(111) system forms through the Stranski-Krastanow mechanism; namely, first a two-dimensional transition layer (reconstruction) with the (2×1) structure forms and then three-dimensional silicide crystallites grow on it. A specific feature of this system is a low rate of diffusion of Si atoms in the europium silicides. This feature accounts for the concentration gradient of Si atoms across the silicide film thickness and, as a consequence, the multiphase film composition.

Low-energy electron diffraction, thermodesorption spectroscopy, and contact potential difference techniques were used in a first study on the coadsorption of Sm and Yb atoms on the Si(111) surface. At comparatively low coverages, in both one-component adsorption systems of the rare-earth metal-Si(111) type and the two-component system (Sm + Yb)-Si(111), the same sequence of diffraction patterns of the (n×1) type, where n=3, 5, and 7, was observed. This indicates that Sm and Yb atoms occupy the same adsorption centers in a mixed film. At higher coverages, at which the \((\sqrt 3 \times \sqrt 3 )R30^\circ \) reconstruction forms in the case of the Sm-Si(111) system and the surface undergoes the 2×1 reconstruction in the Yb-Si(111) system, the structure of the mixed film is governed by the ytterbium coverage θ(Yb). At low ytterbium coverages, θ(Yb) 0.15, however, the former pattern disappears, whereas the latter persists. A comparison of this evolution of a binary adsorbed layer with the properties of the Sm-Si(111) and Yb-Si(111) systems indicates its anomalous character.