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Cd1−xZnxTe (CZT)-based matrices have highest absorption capabilities and tunable band gap, so it can be utilized as the central most significant photon absorption layer. In this research, we have briefly investigated the effect of annealing dynamics over the phosphorus ion (P+) implanted Cd1−xZnxTe on different stoichiometric ratios. The P+ ions are introduced at 800 keV in order to tailor/tune the electro-optical characteristics of said ternary compound matrix for its utilization as an active medium in photovoltaic and related application. In this specific study, the annealing dynamics of P+ implanted Cd1−xZnxTe scheme have been studied, and three temperature ranges were chosen ~ 300, 350, and 400 °C for such purpose. The impact of annealing behavior has been envisaged by electrical and electro-optical characterization techniques, i.e., current–voltage (I–V), activation energy, charge-based deep-level transient spectroscopy (Q-DLTS) and transient of photo-voltage (TPV). From Q-DLTS study, one has obtained different defect levels that may limit the overall performance of the as-implant CZT matrix. By adopting RTA process, the damage content in form of trap levels has shifted themselves near premises to their respective band edges i.e., for as-implant cases, the trap level placed near the Fermi level and when the RTA process subjected the trap levels localized themselves to the close proximity to either of its band edge (valance/conduction level), e.g., the trap level of CdTe shift from 0.123 to 0.005 eV, i.e., near the valance band edge which may enhance the trap characteristics. Also, the activation energy and transient of photo-voltage analysis direct the physical importance of RTA process because this process may provide significant increase of carrier’s generation by reduction in activation energy and elevation of photo-voltage by utilizing the appropriate annealing sequence to subject CZT crystal. The TPV analysis of Cd0.75Zn0.25Te sample shows higher extent of physical voltages ~ 63 mV at 400 °C annealing sequences, whereas for as-implant case provides just ~ 10 mV.

Ternary compound semiconductor Cu3BiS3 has been perceived as a potential candidate of solar absorber materials in recent years, due to the low–toxic and earth–abundant component elements as well as excellent optoelectronic properties. However, the fundamental properties vital for Cu3BiS3 photovoltaic device have not been fully explored and the efficiency is still at an extremely low level. Herein, a cation doping strategy was introduced during preparing Cu3BiS3 absorber layers to optimize the material properties and thereby improve the device performances. Basing on a one-step solution method, the effects of Ag doping on the structural, optical, electrical and photovoltaic behaviors of Cu3BiS3 film were investigated in detail. Our results demonstrate that appropriate Ag doping can enlarge the grain size, improve the film compactness, enhance the light absorption, broaden the band gap and increase the carrier concentration of absorber layer. As a result, the photovoltaic performance is also evidently promoted, achieving a highest efficiency improvement of ~85% relative to the undoped Cu3BiS3 solar cell device. Higher Ag incorporation, however, causes phase separation and dramatically deteriorates the absorber properties.

Demand for simple and effective gas sensing sensors is growing rapidly due to the growing threat of triethylamine (TEA). Semiconductor tin oxide (SnO2) is one of the most widely used sensing materials for metal oxide gas sensors. In recent years, a lot of binary ternary compound researches have been carried out. In this paper, five different SnO2 samples were synthesized by simple synthesis method to understand the internal relationship and obtain different gas sensing characteristics. Based on the low temperature nitrogen adsorption tests and the atomic arrangement model, it can be inferred that different exposed surfaces play a key role in TEA sensing properties. In addition, the TEA sensing activity relationship of SnO2 exposed crystal faces is proposed as listed: (200) > (101) > (110).

Research on photovoltaic solar cells has always been exciting due to its clean and green nature. However, the quest for alternative approaches to the design of highly efficient solar cells with optimal cost-efficiency ratios has also been progressing. CuSbS2-based ternary compound semiconductor is a promising candidate for the ultrathin film photovoltaic cell due to the high absorption coefficient, low cost, and earth abundant which makes it suitable to use as a thin-film absorber layer. The impact of various parameters such as thickness, bandgap, band alignment, temperature, carrier concentration, and bandgap grading has been studied to optimize the overall performance of the solar device. In present work, we have adopted the Solar Cell Capacitance Simulator in One Dimension (SCAPS-1D) simulation approach to the design of CuSbS2 absorber-based solar heterostructure cells to boost the electrical properties of the solar cell.

Dark current is the main factor that influences photodiode performance. It should be minimal to reduce noise and ensure a high level of photoelectric parameters. In order to identify the predominant causes of generation–recombination in photodiodes based on a mercury–cadmium–tellurium (MCT) ternary compound in the given voltage range, a calculation model is proposed for dark currents caused by fundamental and other current mechanisms. The components of dark current in photodiodes based on MCT heterostructures grown by molecular beam epitaxy (MBE) and liquid-phase epitaxy (LPE) methods are determined in the reverse bias voltages range from 0 to 40 mV. In the range from 0 to 20 mV, these characteristics are reduced to the diffusion component. When the reverse bias voltage exceeds 30 mV, an increase in the Shockley–Read–Hall (SRH) generation–recombination current and tunneling current through trap levels in the band gap is observed.

The diamond-like compound Cu3PSe4 with low lattice thermal conductivity is deemed to be a promising thermoelectric material, which can directly convert waste heat into electricity or vice versa with no moving parts and greenhouse emissions. However, its performance is limited by its low electrical conductivity. In this study, we report an effective method to enhance thermoelectric performance of Cu3PSe4 by defect engineering. It is found that the carrier concentrations of Cu3−xPSe4 (x = 0, 0.03, 0.06, 0.09, 0.12) compounds are increased by two orders of magnitude as x > 0.03, from 1 × 1017 to 1 × 1019 cm−3. Combined with the intrinsically low lattice thermal conductivities and enhanced electrical transport performance, a maximum zT value of 0.62 is obtained at 727 K for x = 0.12 sample, revealing that Cu defect regulation can be an effective method for enhancing thermoelectric performance of Cu3PSe4.

Dual-cathode dc unbalanced magnetron sputtering for the deposition of ternary compound films with a high deposition rate was designed and constructed. It consists of two magnetrons of opposite magnetic polarities. Each magnetron consists of central and outer ring magnets with the residual inductions of 500 and 600 mT, respectively. The testing results of the system showed that high plasma volume could be created at a long substrate distance of about 15 cm from the targets. In addition, by using this sputtering system for coating TiAlN film, the result showed that at a target to substrate distance of 13 cm the film growth rate was 7.3 nm/min. It indicates that the sputtering system developed in this study is suitable for large substrate area coating due to the long distance of target to substrate.

This work focuses on the preparation and structural characterization of the semiconductor Cu3In5Se9, an important member of ordered vacancy compounds family, belonging to the semiconductor system I3-III5--VI9, where denotes the cation vacancy which is included in the formula to maintain the same number of cations and anions sites. This material was synthesized by the Bridgman-Stockbarger technique, and its structure was refined from powder X-ray diffraction data using the Rietveld method. Cu3In5Se9 crystallizes with tetragonal symmetry in the space group P2c (Nº 112), with a = 5.7657(1) Å, c = 11.5353(4) Å, V = 383.47(2) Å3. This ternary compound consists of a three-dimensional arrangement of distorted CuSe4 and InSe4 tetrahedral connected by common faces. In this structure, each Se atom is coordinated by four cations located at the corners of a slightly distorted tetrahedron, and each cation is tetrahedrally bonded to four anions. Cu3In5Se9 is related to the p-type CuInSe2 and n-type CuIn3Se5 semiconductor compounds, which are being used in the preparation of high-efficiency solar cells. DO: http://dx.doi.org/10.17807/orbital.v13i3.1560

In this study, we present a quantitative analysis of the electrical properties of a series of bottom- gate top-contact n-channel transparent thin film transistors (TFTs) based on zinc indium tin oxide (Zn-In-SnO) ternary compound with various ZnO content. In addition, the effect of annealing on the TFTs electrical properties was examined theoretically and experimentally. The obtained results revealed that the thermal annealing of fabricated devices in air atmosphere at 300 °C has enhanced their performances; this behavior is well observed for all devices fabricated with different composition of Zn-In-SnO. TFTs having the lowest Zn content of 17.1% and annealed 300°C showed the high electrical performances in term of drain current, saturation mobility, threshold voltage. For the total resistance modeling of the fabricated devices with various content of ZnO and that annealed 300 °C, grain boundary model based on Meyer–Neldel rule was applied. The obtained results revealed that the total resistance was increased with increasing ZnO content. Furthermore, an analytical model has been refined in order to reproduce the current-voltage relationships of the fabricated TFTs using the overall resistance obtained from the NMR–GBT model. The calculated results are in good agreement with the experimental measurements of all fabricated devices. The obtained performance of TFTs based on zinc indium tin oxide with low content of ZnO and annealed will be promising for application in the future backplane of flat panel displays.

Despite the improvements seen in efficiency of GaAs cells over the years, there remains room for improvement for it to approach the theoretical single junction limit posited by Shockley and Quiesser decades ago. One of the more pursued options is the growth of quantum wells within the structure of GaAs to enhance its photon absorption below its bandgap. Multiple Quantum Wells (MQW) have been an ongoing topic of research and discussion for the scientific community with structures like InGaAs/GaAs and InGaP/GaAs quantum wells producing promising results that could potentially improve overall energy conversion. Here, we used WEIN2K, a commercial density functional theory package, to study the ternary compound Ga1-xTlxAs and determine its electronic properties. Using these results combined with experimental confirmation we extend these properties to simulate its application to form a MQW GaAs/ Ga1-xTlxAs solar cell. Ga1-xTlxAs is a tunable ternary compound, with its bandgap being strongly dependent on the concentration of Tl present. Concentrations of Tl as low as 7% can reduce the bandgap of Ga1-xTlxAs to roughly 1.30 eV from GaAs’s 1.45 eV at room temperature with as little as a 1.7% increase in lattice constant. The change in bandgap, accompanied by the relatively small change in lattice constant makes Ga1-xTlxAs a strong candidate for a MQW cell with little to no strain balancing required within the structure to minimize unwanted defects that impede charge collection within the device. Our GaAs photodiode with TlGaAs MQWs shows an expanded absorption band and improved conversion efficiency over the standard GaAs photovoltaic cell with dilute concentrations of Tl incorporated into the compound.

Copper indium diselenide (CuInSe2) is a prototype ternary compound and group I–III–VI semiconductor with useful optoelectronic properties. CuInSe2 nanocrystals have been of significant interest because of their size-tunable optical properties and lack of toxic heavy metals. Because of the particular vacancy and antisite substitutional point defects in CuInSe2, large stoichiometric deviations can be tolerated, sometimes leading to the so-called ordered vacancy compounds (OVCs). Here, we use Raman spectroscopy of oleylamine-capped CuInSe2 nanocrystals and ab initio lattice dynamics modeling to study the concentration and arrangements of (2vCu– + InCu2+) defect pairs in the nanocrystals. The nanocrystals have randomly distributed defect pairs that become mobile under light excitation and accumulate, as in OVCs, along the [100] direction. Because the high concentration of vacancies in CuInSe2 nanocrystals is compensated by InCu2+ antisite defects, these nanocrystals do not exhibit an optical plasmon resonance...

BGaAs/GaAs epilayers and BInGaAs/GaAs quantum well (QW) have been prepared using metal-organic chemical vapor deposition under different growth conditions, and their physical and structural properties have been examined. SEM-EDS investigation showed a dependence of surface properties of the ternary compound on the growth conditions. High-resolution X-ray diffraction evidenced a tensile strain for the ternary alloys whatever the growth condition, while the quaternary QW always shows a compressive strain state. Room temperature optical absorption allowed to follow the variation of the bandgap with boron incorporation. Photoluminescence measurements confirmed the carrier-localization phenomenon and its dependence with the growth conditions. Deposition temperature and diborane (B2H6) flow rate are with particularly significant effects on the optical properties: lower diborane flow rate and high growth temperature enhance the radiative emission. Computer simulation using localized state ensemble model quantitatively relates the lattice inhomogeneity to the optical properties and suggests a way to engineer the localization phenomenon and avoid clustering effects. Electrical investigations by current-voltage, capacitance and conductance methods have been performed for the first time on selected BGaAs samples. The ideality factor of Schottky barriers has been determined, while their height and film doping level could only be approximately estimated. Such physical properties make boron-based alloys very promising for applications in multijunction solar cells.

Bi2X3 (X = S, Se, and Te) binary compounds have been widely studied as thermoelectric materials and reference topological insulators. Replacing one of the X atoms with a different atom Y of the same group has resulted in a new family of ternary compounds Bi2X2Y (X, Y = O, S, Se, and Te), which have attracted increasing attention very recently. By means of first-principles calculations within density functional theory, we have systematically studied the geometric structures and electronic properties of the whole family of these ternary compounds. We find that these compounds can be divided into two major groups. The first is traditional semiconductors, which include (i) Bi2O2Y, (ii) Bi2S2Y, and (iii) Bi2OY2. The other is topological insulators, which are (i) Bi2Se2Y and (ii) Bi2Te2Y. The optimized lattice parameters, band gaps as well as effective masses are in excellent agreement with recently available experimental measurements. In particular, we have found a new semiconductor material Bi2S2Te, which possesses an orthorhombic structure in space group pnma with a moderate direct gap of 0.5 eV at the HSE06 level and a small hole effective mass (∼0.22m0), which should favour fast hole transport and deserves further experimental studies. This work provides a road map for the exploration of the fundamental properties of the ternary compounds in this family as well as for their practical applications at the device level.

Recently, the ternary compound, CuSbS2, has been attracting a lot of interest in developing sustainable photovoltaic energy conversion because of its use as an absorber layer material due to the low toxicity, cost and abundance of constituents in nature. However, the recent conversion efficiencies reported for copper antimony sulfide (CAS) thin-film photovoltaics is still about 3%. Consequently, this research work is geared toward optimising the absorber layer material using numerical modelling and simulation to enhance the device performance. The simulation of the baseline model was achieved using the Solar Cell Capacitance Simulator (SCAPS-1D). Results of the simulation showed good agreement with experimental results. Subsequently, a step by step optimisation was done on the absorber layer. The optimisation process includes the variation of the acceptor concentration at various thicknesses, followed by the electron affinity and the back-contact metal work function. Results showed that the optimal carrier concentration of CuSbS2 is 1 × 10 17 c m − 3 at a thickness of 2.6 μm. The electron affinity of 4.15 eV was obtained as the optimum value of the absorber. Also, it suggests that the back contact electrode optimal work function is 5.0 eV, which corresponds to that of Molybdenum. A combination of these optimisations doubled the recent experimentally obtained photo-conversion efficiency with a value of 7.42%.

Solidly mounted resonator is a type of film bulk acoustic resonator for microwave operation applications. ZnO piezoelectric films provide a choice to produce solidly mounted resonator, but show a low longitudinal acoustic velocity and a relatively low response. In this work, a ternary compound magnesium doped zinc oxide (Mg x Zn 1-x O) piezoelectric film is introduced and investigated, which has a flexible frequency response and a higher acoustic velocity. X-ray diffraction (XRD) θ-2θ coupled scans of the Mg x Zn 1-x O films are investigated versus different RF magnetron sputtering deposition conditions. Residual stresses are studied to ensure a reliable fabrication of solidly mounted resonators. A typical device fabricated based on Mg x Zn 1-x O piezoelectric film show a resonant frequency at 2.046 GHz with a return loss of −38.9 dB, a quality factor of 965 and a coupling coefficient of 2.5%. The calculated longitudinal acoustic velocity of a Mg x Zn 1-x O film is 6854.1 m/s, faster than that of ZnO.

Owing to their high extinction coefficient and moderate band gap, cadmium chalcogenides are known as common semiconductors for photoelectric conversion. Nevertheless, no ideal cadmium chalcogenide with proper band structure is available yet for photoelectrochemical hydrogen evolution. In this work, we modified the band structure of CdTe via alloying with Se to achieve a ternary compound (CdSe0.8Te0.2) with n-type conduction, a narrower band gap, and a more negative band position compared to those of CdSe and CdTe. This novel material exhibits strong light absorption over a wider spectrum range and generates more vigorous electrons for hydrogen reduction. As a result, a photoelectrode based on nanoflake arrays of the new material could achieve a photocurrent density 2 times that of its CdSe counterpart, outperforming similar materials previously reported in the literature. Moreover, the quick transfer of holes achieved in the novel material was found to depress photocorrosion processes, which led to improv...

To reveal the complicated mechanism of the multicomponent mass transfer during the growth of ternary compound semiconductors, a numerical model based on Maxwell-Stefan equations was developed to simulate the Bridgman growth of CdZnTe crystal. The Maxwell-Stefan diffusion coefficients in the melt were estimated. Distributions of Zn, Cd, and Te were calculated with variable ampoule traveling rate and diffusion coefficients. The experimental results show that Zn in melt near the growth interface decreases and diffuses from the bulk melt to the growth interface. For Cd, the situation is just the opposite. The coupling effects of Zn and Cd diffusions result in an uphill diffusion of Te at the beginning of the growth. Throughout the growth, the concentration of Te in the melt keeps low near the growth interface but high far from the growth interface. Increasing the ampoule traveling rate will aggravate the segregation of Zn and Cd, and hence deteriorate the uniformity of Te. We also find that not only the diffusion coefficients but also the ratios between them have significant influence on the species diffusions.

This work takes place in the context of the development of a transport phenomena simulation based on group III nitrides. Gallium and boron nitrides (GaN and BN) are both materials with interesting physical properties; they have a direct band gap and are relatively large compared to other semiconductors. The main objective of this paper is to study the effect of boron content on the electron transport of the ternary compound BxGa(1-x)N and the effect of the temperature of this alloy at x=50% boron percentage, specifically the piezoelectric, acoustic, and polar optical scatterings as a function of the energy, and the electron energy and drift velocity versus the applied electric field for different boron compositions (BxGa(1-x)N), at various temperatures for B0.5Ga0.5N. Monte carlo simulation, was employed and the three valleys of the conduction band (Γ, L, X) were considered to be non-parabolic. We focus on the interactions that do not significantly affect the behavior of the electron. Nevertheless, they are introduced to obtain a quantitative description of the electronic dynamics. We find that the form of the velocity-field characteristic changes substantially when the temperature is increased, and a remarkable effect is observed from the boron content in BxGa(1-x)N alloy and the applied field on the dynamics of holders within the lattice as a result of interaction mechanisms.

Ternary chalcogenide semiconductor copper germanium sulfide (Cu 2 GeS 3 ) composed of earth-abundant and non-toxic elements is considered to be a suitable light harvesting material for photovoltaics. In this study, Cu 2 GeS 3 thin film solar cells are creatively fabricated based on combustion method. XRD and Raman analyses reveal that the combustion synthesized product is composed of Cu-Ge alloy rather than metal oxides. The structural, morphological, optical and electrical properties of CGS films are analyzed in detail. The best power conversion efficiency of Cu 2 GeS 3 thin film solar cell achieve 2.67% with a high open-circuit voltage of 592 mV. The experiment results reveal that the p-type semiconductor Cu 2 GeS 3 is an extremely promising light harvesting material for photovoltaics due to its suitable band gap and carrier concentration.

A ternary compound semiconductor ZnSnP2 has the order–disorder transition, where the ordered and disordered phases are chalcopyrite (I42d, a = 5.651 A, c = 2a) and sphalerite (F43m, a = 5.651 A), respectively. In this study, the quantitative relationship between bandgap and long-range order parameter η was investigated by analyzing ZnSnP2 bulk crystals obtained by various cooling rates in crystal growth. The Chipman and Warren method was used to evaluate the long-range order parameters from X-ray difffaction profiles. The results showed that the long-range order parameter η decreases from 0.94 to 0.54 with the increase in cooling rates, and the bandgap gradually reduced from 1.60 to 1.37 eV, corresponding to the η value. It was also demonstrated that bandgap tuning of ZnSnP2 was possible by controlling the long-range order parameter through annealing process. This study clarified the effects of the order–disorder phenomena on bandgap in a model material, ZnSnP2, based on the evaluation of long-range ord...

Semiconductor nanowires are versatile building blocks for optoelectronic devices, in part because nanowires offer an increased freedom in material design due to relaxed constraints on lattice matching during the epitaxial growth. This enables the growth of ternary alloy nanowires in which the bandgap is tunable over a large energy range, desirable for optoelectronic devices. However, little is known about the effects of doping in the ternary nanowire materials, a prerequisite for applications. Here we present a study of p-doping of InxGa1-xP nanowires and show that the growth dynamics are strongly affected when diethylzinc is used as a dopant precursor. Specifically, using in situ optical reflectometry and high-resolution transmission electron microscopy we show that the doping results in a smaller nanowire diameter, a more predominant zincblende crystal structure, a more Ga-rich composition, and an increased axial growth rate. We attribute these effects to changes in seed particle wetting angle and increased TMGa pyrolysis efficiency upon introducing diethylzinc. Lastly, we demonstrate degenerate p-doping levels in InxGa1-xP nanowires by the realization of an Esaki tunnel diode. Our findings provide insights into the growth dynamics of ternary alloy nanowires during doping, thus potentially enabling the realization of such nanowires with high compositional homogeneity and controlled doping for high-performance optoelectronics devices.

CuGaSe 2 is an important thin film electronic material that possesses several attributes that make it appealing for solar energy conversion. Due to its properties it can be incorporated in to various devices, among the greatest highlights are photovoltaic cells, as well as its potential use as photocathodes for hydrogen production, via the photoelectrolysis. There are several methods of its preparation, most notably electrodeposition that has the potential for large areas and high volumes. Electrodeposition of ternary and/or quaternary semiconductors generally proceeds via the formation of a binary, which is subsequently reacted to form the ternary compound. Several conditions must be controlled to form binary compounds that include the use of complexing agents, buffers, temperature, etc. In this paper, we discuss the effect of anion composition in the electrolytic bath and the type of lithium salts, in order to manipulate the atomic concentration of CuGaSe 2 during the electrodeposition of thin films, yielding copper-rich, gallium-rich or stoichiometric thin films. We also present the results of a study on the morphology and structure obtained using two types of substrates both before and after performing a heat treatment.

A silicon based ternary compound was supposed to be solid synthesized with In, Si and O elements by magnetron sputtering of indium tin oxide target (ITO) onto crystal silicon substrate at 250 °C. To make clear the configuration of the intermediate region, a potential method to obtain the chemical bonding of Si with other existing elements was exploited by X-ray photoelectron spectroscopy (XPS) instrument combined with other assisted techniques. The phase composition and solid structure of the interfacial region between ITO and Si substrate were investigated by X-ray diffraction (XRD) and high resolution cross sectional transmission electron microscope (HR-TEM). A photovoltaic device with structure of Al/Ag/ITO/SiOx/p-Si/Al was assembled by depositing ITO films onto the p-Si substrate by using magnetron sputtering. The new matter has been assumed to be a buffer layer for semiconductor-insulator-semiconductor (SIS) photovoltaic device and plays critical role for the promotion of optoelectronic conversion performance from the view point of device physics.

Nowadays, the attention of researchers is focused on the large family of chalcogenides that poses very unique and interesting properties. One of them is the teallite – PbSnS2, almost unrevealed ternary compound, promising thermoelectric material. In this work, we present first detailed Raman studies of PbSnS2, including the polarization-dependent and temperature-dependent measurements (80–400 K range). The strong effect of polarization angle and temperature on the Raman spectra was observed. The polarization studies allowed to assign symmetry of observed modes. The temperature evolutions of the Raman spectra were explained by optical phonon decay into two or three acoustic phonons with equal energies. The extracted first-order temperature coefficients are among the largest reported so far for layered materials. Our results might be helpful in understanding the anisotropic optical, thermal and electrical properties of PbSnS2. Copyright © 2016 John Wiley & Sons, Ltd.

A distinct materials combination is presented for tunnel field-effect transistors (TFETs): gallium arsenide phosphide (GaAsP) as a wider-bandgap material in the drain and channel regions with indium gallium arsenide (InGaAs) as a narrow-bandgap material for the source region. The introduction of this novel materials combination greatly improves the ON-state current, OFF-state current, ambipolar behavior, threshold voltage, and subthreshold slope compared with other group III---V ternary heterojunction TFETs. In GaAsP---InGaAs TFETs, the ambipolar current remains equal to the OFF-state current. This paper explores the potential of the proposed device for ultralow-power high-performance applications.

In this work, we developed a technology for growing a single crystal of a ternary compound, using the Atomic Force Microscope (AFM), we studied the surface microrelief in 2D and 3D modes, using X-ray diffraction (XRD) analysis, determined the parameters of the unit cell of this phase and revealed that it crystallizes in tetragonal symmetry with lattice parameters [Formula: see text] Å and [Formula: see text] Å, space group I4/mcm. Using the density functional method, using the ABINIT software package, using the Troiller–Martins pseudopotentials in the basis of plane waves, the band structure was calculated, the origin of the valence and conduction bands was determined. It was revealed that this phase is a direct-gap semiconductor with a bandgap of 0.56 eV. The parameters of the InGaTe2 unit cell were calculated by the pseudopotential and linearized attached plane wave (LAPW) methods, the theoretical and experimental values of the lattice parameters are in good agreement. Based on the band structure, the effective masses of electrons and holes are determined. It is shown that the tensors of the inverse effective mass for both extreme have a diagonal form.

With their broad range of properties, ternary chalcogenides have long served as a platform for optoelectronic as well as photovoltaic applications. In this paper, we present for the first time a theoretical study of the layered Sn2Sb2S5 ternary compound. To do this task, we carried out first-principles calculations within the density functional theory framework. It has been shown that Sn2Sb2S5 has dynamical stability in the layered orthorhombic structure. Additionally, to evaluate the correct bandgap as well as their related optical properties the modified Becke-Johnson potential was employed. It is shown that the investigated material has a narrower bandgap favoring visible optoelectronic applications. The bonding properties were deeply analyzed; the results show that the chemical pattern of Sn2Sb2S5 is mainly governed by covalent lone pair and strong van der Waals interactions.

The n-type PbTe still maintains relatively low thermoelectric performance compared with its p-type counterpart. Thus, to promote its performance in n-type PbTe, we conduct successive strategies that firstly suppressing the lattice thermal conductivity (κlat) through alloying with ternary compound AgSbSe2, and then optimizing carrier density with Sb, Bi or I doping. In AgSbSe2-alloyed PbTe samples, the κlat can be evidently reduced, and the minimum κlat decreases from ∼1.1 Wm−1K−1 in undoped PbTe to ∼0.8 Wm−1K−1 in PbTe–5%AgSbSe2. Based on PbTe–5%AgSbSe2 matrix, several dopants (Sb, Bi or I) are used to optimize its carrier density, and found that I element is verified to be the most effective dopant to enhance its electrical transport properties. In I-doped PbTe–5%AgSbSe2 samples, the carrier density raises from ∼2.49 × 1016 cm−3 in PbTe–5%AgSbSe2 to ∼1.15 × 1019 cm−3 in PbTe0.992I0.008-5%AgSbSe2, which contributes to the maximum power factor ∼14.8 μWcm−1K−2. Combining the reduced lattice thermal conductivity and improved power factor, the maximum ZTmax and average ZTave values in PbTe0.992I0.008-5%AgSbSe2 are boosted to ∼1.0 at 723 K and ∼0.77 at 300–823 K, respectively. This work points out a valid avenue to improve thermoelectric transport property in n-type PbTe with separately successive strategies to adjust its thermal and electrical performance.

The electronic, optoelectronic, and thermoelectric properties of a ternary structure MgSrSe2 are investigated using density functional theory. MgSrSe2 is found to be a direct bandgap semiconductor with a bandgap of 2.04 eV. The photon energy calculated results show that the absorption spectra are in UV-A light, and MgSrSe2 could be applied for a photodetector. Optoelectronic properties, such as the dielectric function, absorption coefficient, reflectivity, refractive index, extinction coefficient, and energy-loss of MgSrSe2, are systematically discussed. The effective mass of the band edge curvature analysis indicates that the p-type MgSrSe2 is suitable for the thermoelectric material, and the maximum dimensionless figure of merit value can be up to 1.33 at 800 K. The results show that MgSrSe2 is a potential optoelectronic and thermoelectric material, and encourage further experimental works for its synthesis.

Cadmium zinc telluride is a tunable band gap II–VI compound semiconductor, which has received considerable attention due to its applications such as nuclear radiation detectors and industrial process monitoring. We have studied the optical properties of the ternary compound semiconductors Cd1-xZnxTe grown by vertical Bridgman-Stockbarger method in the whole range of zinc content 0

Buffer layers, such as CdS and MgxZn1–xO (MZO), are critical for CdTe and other thin film polycrystalline solar cells. A ternary compound, such as MZO, allows for interface engineering by adjusting...

HgCdTe crystals are very important semiconductors for the realization of infrared (IR) detectors, and as a rule an optimal response range is usually expected by controlling the exact balance of the ternary compound. Two approaches are available for the synthesis of HgCdTe semiconductors. The first is the well-known alloy process, in which the bandgap is tailored by varying the mole fraction x of CdTe in an Hg 1-x Cd x Te alloy. The second is a superlattice structure, in which the bandgap is determined by the relative thicknesses of alternating HgTe and CdTe layers in a composite semiconductor. This Overview concerns colloidal synthesis, which is used as a new technology for obtaining new plasmon materials - transparent self-assembled conductive Ag 2 O, Ag, graphene oxides in the production of plasmon material based on HgCdTe (MCT). In general, the results will be used to create multi-range HgCdTe detectors based on the plasmon resonance effect.

CdZnS quantum dots (QDs) QDs containing concentrations of 0.25, 0.5, 1, 3 and 5% Zn were synthesized at room temperature by chemical precipitation method and then incident photons to current efficiency (IPCE) measurements were performed to determine optimum Zn concentration in CdZnS QDs. Moreover, Zn2SnO4, a ternary compound semiconductor, was used instead of TiO2 as counter electrode for the first time. As a last part of the study, the structural and optical properties of CdZnS QDs containing optimum Zn content were investigated, respectively. Consequently, it appears that CdZnS QDs have a higher efficiency than CdS and that Zn doping plays an important role in this increase.

The layered ternary compound TaIrTe4 is an important candidate to host the recently predicted type-II Weyl Fermions that break Lorentz invariance. Photodetectors based on Weyl semimetal promise extreme performance in terms of highly sensitive, broadband, and self-powered operation owing to its topologically protected band structures. In this work, we report the realization of a broadband self-powered photodetector based on TaIrTe4. The photocurrent generation mechanisms are investigated with power- and temperature-dependent photoresponse measurements. The prototype metal-TaIrTe4-metal photodetector exhibits a responsivity of 20 μA W–1 or a specific detectivity of 1.8 × 106 Jones with 27 μs response time at 10.6 μm. Broadband responses from 532 nm to 10.6 μm are experimentally tested with potential detection range extendable to far-infrared and terahertz. Furthermore, anisotropic response of the TaIrTe4 photodetector is identified using polarization-angle-dependent measurement with linearly polarized light. The anisotropy is found to be wavelength dependent, and the degree of anisotropy increases as the excitation wavelength gets closer to the Weyl nodes. Our results suggest this emerging class of materials can be harnessed for broadband, polarization angle-sensitive, self-powered photodetection with reasonable responsivities.

Alx Ga1-x N thin-film-based piezotronic strain sensors with ultrahigh strain sensitivity are fabricated through alloying of AlN with GaN. The strain sensitivity of the ternary compound Alx Ga1-x N is higher than those of the individual binary compounds GaN and AlN. Such a high performance can be attributed to the piezoelectric constant enhancement via intercalation of Al atoms into the GaN matrix, the effect of residual strain, and a suppressed screening effect.

The optical absorption coefficient α as a function of the incident photon energy hν at different temperatures between 50 and 300 K and the infrared spectra between 80 and 375 meV have been studied in the ternary compound CuGaSe2 and the ordered defect compound CuGa3Se5. It is found that the phonon energy hνp involved in the formation of Urbach tail is much higher than the highest lattice vibrational modes in these compounds. A combined analysis of the Raman modes and infrared spectra shows, after discarding the possible donor/acceptor transitions, replicas of phonon modes at higher energies in both Raman and infrared spectra, and the peaks originating from the spectrophotometer, that the average phonon energy h ν p ∗ of the remaining lattice vibrational and localized modes are in good agreement with the phonon energy hνp obtained from the study of Urbach tail. This confirms that in the formation of Urbach tail, in addition to the contribution of lattice vibrational modes, other localized modes caused by structural defects and enhanced electronic distortion, originating from ordered defects, are also involved. It is suggested that this type of study can be a useful tool in determining the quality of the samples and the ingots, important in device applications.

The visible-light-induced gas sensors based on the ternary compound CdSxSe1−x nanoribbons have been successfully fabricated. The compound was obtained via a metal-catalyzed physical evaporation route. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were employed to confirm the formation and composition of CdSxSe1−x nanoribbons. The optimum operating temperature of CdSxSe1−x-based gas sensors in the dark is 200 °C when they were used in detection of acetic acid with the concentration range from 25 to 400 ppm, while the optimum operating temperature could be reduced by approximately 100 °C under visible light irradiation. More importantly, the sensors can even work efficiently at room temperature under visible light. The calculated limit of detection decreased from 1.13 ppm (200 °C, dark) to 0.87 ppm (100 °C, visible light) and 1.03 ppm (room temperature, visible light), respectively. The enhanced sensing properties of the CdSxSe1−x-based gas sensors were due to photo-generated electrons. This work will pave a way for the development of the low-cost practical gas sensors.

Presented in this work are the results concerning formation of nano-scale patterns on the surface of a ternary compound Hg1–xCdxTe (x ∼ 0.223). Modification of this ternary chalcogenide semiconductor compound was performed using the method of oblique-incidence ion bombardment with silver ions, which was followed by low-temperature treatment. The energy and dose of implanted ions were 140 keV and 4.8×1013 cm-2, respectively. Atomic force microscopy methods were used for the surface topography characterization. The structural properties of MCT-based structure was analyzed using double and triple crystal X-ray diffraction to monitor the disorder and strain of the implanted region as a function of processing conditions. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Refinement of the class A I B II C V materials continue as a candidate for solid-state neutron detectors. Such a device would have greater efficiency, in a compact form, than present day gas-filled 3 He and 10 BF 3 detectors. The 6 Li( n , t ) 4 He reaction yields a total Q value of 4.78 MeV, larger than 10 B, and easily identified above background radiations. Hence, devices composed of either natural Li (nominally 7.5% 6 Li) or enriched 6 Li (usually 95% 6 Li) may provide a semiconductor material for compact high efficiency neutron detectors. A sub-branch of the III–V semiconductors, the filled tetrahedral compounds, A I B II C V , known as Nowotny–Juza compounds, are known for their desirable cubic crystal structure. Starting material was synthesized by equimolar portions of Li, Zn, and As sealed under vacuum (10 −6 Torr) in quartz ampoules with a boron nitride lining, and reacted in a compounding furnace [1] . The synthesized material showed signs of high impurity levels from material and electrical property characterization. In the present work, a static vacuum sublimation of synthesized LiZnAs loaded in a quartz vessel was performed to help purify the synthesized material. The chemical composition of the sublimed material and remains material was confirmed by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Lithium was not detected in the sublimed material , however, near stoichiometric amounts of each constituent element were found in the remains material for LiZnAs. X-ray diffraction phase identification scans of the remains material and sublimed material were compared, and further indicated the impurity materials were removed from the synthesized materials. The remaining powder post the sublimation process showed characteristics of a higher purity ternary compound.

We identify a new ternary compound, ReCN and characterize its properties including structural stability and indicators of hardness using first principles calculations. We find that there are two stable structures with space groups P63mc (HI) and P3m1 (HII), in which there are no C–C and N–N bonds. Both structures, H1 and III are elastically and dynamically stable. The electronic structures show that ReCN is a semiconductor, although the parent compounds, ReC2 and ReN2 are both metallic. ReCN is found to possess the outstanding mechanical properties with the large bulk modulus, shear modulus and excellent ideal strengths. In addition, ReCN may perhaps be synthesized relatively easily because it becomes thermodynamic stable with respect to decomposition at very low pressures.

The ternary compound Cu2SnS3 (CTS) is composed of elements that are low in cost, non-toxic, and abundant in the Earth's crust. In addition, CTS is a p-type semiconductor with a high reported absorption coefficient of more than 104 cm−1 and a band gap energy of 0.92–1.77 eV. It is, therefore, considered to be a suitable candidate for the absorber layer in thin film solar cells. In the present study, CTS thin films were produced by first depositing precursor films by co-evaporation of Cu, Sn, and S, and then annealing them. Solar cells were then fabricated using the CTS films as absorber layers, and the dependence of their photovoltaic properties on the annealing temperature was investigated. The solar cell using the CTS thin film annealed at 570 °C exhibited an open-circuit voltage of 248 mV, a short-circuit current density of 33.5 mA/cm2, a fill factor of 0.439, and a conversion efficiency of 3.66%.

It is ~50 years now since the first development of the ternary compound cadmium mercury telluride (MCT) in bulk crystal form for infrared (IR) applications. MCT (Cd x Hg1–x Te) is still the pre-eminent infrared material, and by varying the x value the material can be made to cover all the important IR ranges of interest (i.e. 1–3, 3–5 and 8–14 μm). The first half of its history really concerned the use of bulk-grown slices to produce a wide range of photoconductive (PC) IR detectors for various applications in the longwave (8–12 μm), midwave (3–5 μm) and shortwave (1–3 μm) regions. The second half of its history has seen its main function supplanted by various forms of epitaxial growth, particularly liquid phase epitaxy, metal-organic vapor phase epitaxy and molecular beam epitaxy, to produce the more versatile photovoltaic focal plane arrays (FPA) currently being manufactured. However, there have been small pockets of activity across the world during the last 25 years studying defects, growth issues, some residual PC detector work and lately its use in large-area optical components that give protection to MCT FPAs in niche applications. It is this later period that forms the focus of this paper.

Defect calculations are standard practice for understanding the electronic structure of dopants and alloying elements in semiconductors and insulators. However, these calculations have untapped potential to quantitatively determine thermodynamic properties of doped semiconductor systems. We present a methodology which couples defect energetics and compound formation energies to determine defect concentrations in a host material as functions of temperature and chemical equilibrium. From these defect concentrations we find the solvus boundaries of the host phase in a multi-dimensional composition space. As an example, we present first-principles calculations of the solvus boundaries of PbTe and PbS in Na–Pb–Te and Na–Pb–S. We calculate the formation energies of compounds in Na–Pb–S–Te and the defect energetics of a large number of intrinsic and Na-containing defects in PbTe and PbS. With these, we obtain equilibrium defect concentrations and solvus boundaries for PbTe and PbS. We find vacancies are the lowest-energy intrinsic defects in PbTe and PbS. We also find Na substituted for Pb is the lowest-energy Na defect in both PbTe and PbS. We find that the PbTe solvus boundary in Na–Pb–Te is a sharply peaked function of composition. We find negative defect formation energies for Na on Pb in PbS, suggesting the existence of a ternary compound in the Na–Pb–S system. The methodology presented herein is a general and straightforward way to extend the use of defect calculations from making inferences about the electronic structure of dopants to calculating solvus boundaries in multicomponent systems.

InGaAs nanowires offer great promise in fundamental studies of ternary compound semiconductors with variable composition and opens up a wide range of applications due to their bandgap tunability and high carrier mobility. Here, we report a study on the growth of Au-seeded InGaAs nanowires by metal-organic vapour phase epitaxy and present a model to explain the mechanisms that govern the growth and composition evolution in ternary III-V nanowires. The model allows us to further understand the limitations on the growth rate and incorporation of the two group III species imposed by the deposition conditions and some intrinsic properties of the material transport and nucleation. Within the model, the evolution of InGaAs nanowire growth rate and composition with particle size, temperature and V/III ratio is described and correlates very well with experimental findings. The understanding gained in this study should be useful for the controlled fabrication of tunable ternary nanowires for various applications.

CdZnS/ CdZnTe photovoltaic solar cell is proposed in this research work. Solar cell performance is described on the basis of numerical analysis. Heterojunction photovoltaic solar cell performance is simulated and analyzed using simulation software called SCAPS (Solar Cell Capacitance Simulator). The cell structure is based on CdZnTe ternary compound semiconductor as the absorber layer and n- doped Cadmium Zinc Sulphide (CdZnS) as the buffer layer. Analysis is performed on the parameters such as the thickness of the CdZnTe absorber layer and its carrier density, working temperature, CdZnS buffer layer thickness and its carrier density to analyze their effects on the cell performance. The simulations show that the optimized thickness for the absorbing layer and the buffer layer should be from 0.1µm to 5 µm and 0.01µm to 0.1µm, respectively. The optimal photovoltaic properties have been achieved with an conversion efficiency of 25.74% with Fill Factor (FF) =89.03%, short circuit density (J sc ) = 26.348 mA/cm2 and Open circuit voltage (Voc) = 1.0973 V when the thickness and carrier density of the CdZnTe is 0.7-µm and1 × 1015cm-3, carrier density and the thickness of the CdZnS is 1 ×1017cm-3 and 0.05µm respectively. The above results will give some important guide for feasibly of fabricating higher efficiency CdZnTe solar cells.

We present antimonide-based resonant tunneling photodetectors with GaSb/AlAsSb double barrier structures and pseudomorphically grown prewell emitter structures comprising the ternary compound semiconductors GaInSb and GaAsSb. Due to the incorporation of GaInSb and GaAsSb prewell emitters, room temperature resonant tunneling with peak-to-valley current ratios of up to 2.4 are shown. The room temperature operation is attributed to the enhanced Γ-Lvalley energy separation and consequently a re-population of the Γ-conduction band of the ternary compound emitter prewell with respect to bulk GaSb. By integration of a quaternary absorption layer, RTDs photodetectors with cut-off wavelengths up to 3 μm have been realized.

Thin films of AgInSe2 ternary compound were grown by a successive process in which the production of AIS-Ag–AIS-Ag–AIS-Ag layers was deposited by e-beam and thermal evaporation on p-type silicon substrates. The formation of a stoichiometric AgInSe2 thin film with 75.2% crystallinity was achieved and the film had homogenous and smooth surfaces. n-AgInSe2/p-Si structure has exhibited good rectifying behavior with rectification ratio of 3.99 × 103. The ideality factor and saturation current were found to be 1.74 and 2.71 × 10−7 A, respectively. The n-AgInSe2/p-Si heterojunction diode exhibited non-ideal reverse-bias capacitance–voltage (C −2–V) characteristic due to fully depletion of n-AgInSe2 side. The basic photovoltaic parameters of the diode such as open-circuit voltage (V oc), short-circuit current (I sc), and fill factor (FF) were obtained as 0.49 V, 4.03 mA, and 27.65%, respectively.

The paper presents a simulation study using the numerical simulator SCAPS-1D to model ZnO/Cd 0.8 Zn 0.2 S/CuIn (1-y) Ga y Se 2 /CuInSe 2 structures. Effects of thickness of graded and ungraded CIGS absorbers and buffer layers on cell performance have been investigated with the aim to reach a higher efficiency. Quantum efficiency (QE) as function of wavelength and thickness of these layers was studied . The high efficiency of CIGS cells, in order of 22.05%, has reached with the absorbers thickness between 2I¼m and 3.5I¼m and with acceptor concentration of about 2.10 16 cm 3 . Other hand, we investigate the effect of Cd 0.8 Zn 0.2 S ternary compound buffer on the top of the p-CIGS cell. These simulation results give some important indication to enable further development of multilayer thin-film solar cells based on CuInGaSe 2 with Cd 0.8 Zn 0.2 S as buffer layer instead of CdS

Thin film of ternary compound semiconductor, copper cadmium sulphide (CuCdS2) was deposited on glass substrate by low temperature solution process. The deposited CuCdS2 thin film was found to suitable for the fabrication of efficient thin film solar cells at low cost. Hexagonal structure of poly crystalline CuCdS2 was formed from the combination of its binary constituents CuxS and CdS. The film was continuously coated and particles were aggregated like spherical granules. The presence of elements Cu, Cd and S were confirmed by electron energy loss spectroscopy and X-ray photoelectron spectroscopy. The absorption spectrum showed that the deposited material had wide range of absorption in visible and near-IR region (300–1100 nm) and band gap was estimated to be 1.42 eV using Tauc’s plot. Vibration modes of CdS and CuxS binary phases were observed and shift between them revealed the existence of binding state between CdS and CuxS. Hall measurement showed p-type conducting nature of charge carriers with higher carrier concentration 3.48 × 1018 cm−3. The mobility and resistivity were measured to be 10.63 cm2/V s and 0.17 Ω cm, respectively. The analyses revealed that the deposited CuCdS2 thin film was suitable material for the fabrication of thin film solar cells at low cost.