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This paper presents an analytical review that addresses physicochemical principles underlying the synthesis of granular structures in semiconductor–ferromagnet systems. Such systems comprise a II–IV–V2, II2–V3, or II–V2 compound as a semiconductor and MnAs as a ferromagnet. We demonstrate that granular magnetic structures are an alternative to superlattices in spintronic devices and can exhibit giant magnetoresistance and tunneling magnetoresistance effects. It is shown that, owing to the high carrier mobility in semiconductors, they are more attractive as matrices of granular materials than are metals or dielectrics. We have formulated the basic principles underlying the synthesis of granular structures with high magnetoresistance based on eutectic systems. Eutectic crystallization involves simultaneous crystallization of all the constituent phases, leading to the formation of an unusual, fine structure. High cooling rates are favorable for metastable crystallization. This causes a synergistic effect, stimulating nanostructuring and favoring the formation of granular structures. We present results on semiconductor–ferromagnet systems and demonstrate the possibility of producing granular magnetic structures with high magnetoresistance in such systems.

Thin (~50 nm) cadmium arsenide films have been grown by magnetron sputtering on single-crystal silicon and sapphire substrates. Using X-ray diffraction, scanning electron microscopy, atomic force microscopy, and Raman spectroscopy, the composition of the films has been shown to correspond to the Cd3As2 stoichiometry. Along with the α-Cd3As2 phase, the films contained trace levels of the α'-Cd3As2 phase. Annealing at 520 K led to recrystallization and the formation of [112] textured films on single-crystal silicon substrates. In the annealed films, the crystallite size evaluated using the Debye–Scherrer equation was ~30 nm.

We have studied the effect of hydrostatic pressure on the galvanomagnetic properties of a Cd3As2 + 20 mol % MnAs alloy in a transverse magnetic field of up to 4 kOe. The pressure dependences of the Hall coefficient and resistivity for the alloy provide evidence of reversible phase transitions. The observed negative magnetoresistance of the alloy is shown to be induced by high pressure.

We have studied the growth of zinc selenide layers on flat and shaped indium phosphide surfaces. The growth rate of zinc selenide has been shown to depend on substrate orientation. It has been shown that the present results can be useful in designing mesa stripe structures for quantum electronic instruments. We have fabricated mesa stripe laser diodes operating on the absorption band of methane and suitable for producing fiber-optic signal transmission systems.

We have studied the interaction of etchants and etchant mixtures with {100} planes of InP substrates. The results demonstrate that mesa stripes and grooves faceted by a combination of planes differing in polarity—{111}A, {111}B, {110}, {112}A, or {221}A—can be obtained by properly selecting the etchant and the orientation of the mask coating. The mesa stripes have been shown to be faceted by the most close-packed planes and, in the case of polar properties, they are faceted by planes with a low dissolution rate ({111}A for the sphalerite lattice). The most close-packed planes {111}A and {111}B differ in their orientation relative to the (110) and ( $$\bar {1}$$ 10) basal planes.

We have studied the caloric and magnetic properties of alloys in the MnAs–ZnGeAs2 eutectic system. The results demonstrate that the heat effect and temperature range of the ferromagnetic-to-paramagnetic phase transformation depend on the crystallite size of manganese arsenide. Reducing the crystallite size to ≤60 nm causes the heat effect of the transformation to disappear, significantly changes the temperature range of the magnetic transition, and raises the Curie temperature of the alloy to 351 K.

Manganese monoarsenide samples have been prepared by the sealed-ampule technique and characterized by X-ray diffraction, differential thermal analysis, and scanning electron microscopy. The hexagonal- to-orthorhombic phase transition of MnAs has been studied using differential scanning calorimetry (DSC) and magnetic measurements. The enthalpy and temperature range of the transition have been determined to be ΔH =–5.6 J/g and 312.5–319 K, respectively. The enthalpy and temperature range of the transition are influenced by the quality of the samples. The samples containing inclusions of the metastable, orthorhombic phase have a lower enthalpy and broader temperature range of the magnetostructural transformation of manganese monoarsenide. It has been demonstrated that DSC is an effective tool for assessing the quality of MnAs samples. Temperature dependences of specific magnetization and magnetic permeability for MnAs lend support to the DSC results. From these data, the Curie temperature of MnAs has been determined to be 40°C, in good agreement with previously reported data.

We studied the effect of Mn on the structure and properties of Cd3−xMnxAs2 crystals with x = 0–0.24, synthesized by direct fusion of high-purity elements. Obtained X-ray diffraction patters suggest that the incorporation of Mn promotes a structural phase transition from primary α-Cd3As2 (x = 0) phase to the α''– Cd3As2 (x = 0.24) phase, while at intermediate compositions both phases can coexist. In addition, the increase of Mn content results in the decrease of lattice cell parameters, which effectively saturates for x > 0.13. Microstructural, calorimetric and magnetometry studies suggest that at high Mn content (x = 0.24) secondary MnAs phase appears. Using obtained results, we estimated the solubility limit of Mn in Cd3As2 as x~0.13, which corresponds to the formation of ternary Cd3−xMnxAs2 compound where Cd atoms are partially substituted by Mn. Formation of ternary compound was also suggested by the results for Cd3As2 + MnAs composite systems, where we also observed the presence of CdAs2 phase, which is a byproduct of corresponding reaction. Additional studies suggested that the CdAs2 phase formation in composite system can be prevented if one uses the Cd3−xMnxAs2 compound instead of pure Cd3As2 as a matrix material.

Thin cadmium sulfide films grown by pulsed laser deposition on crystalline and amorphous substrates have been shown to consist of a mixture of a cubic (sphalerite structure) and a hexagonal (wurtzite structure) phase. We have demonstrated the possibility of controlling the percentages of the hexagonal and cubic phases in cadmium sulfide films by varying pulsed laser deposition parameters. Varying the deposition parameters allows one to control the optical and structural parameters and surface morphology of thin cadmium sulfide films.

Phase diagram in the ZnSiAs 2 –MnAs nanocomposite system was studied by Х-ray, DTA and SEM. The system has an eutectic character. The coordinates of eutectic are 87±1 mol% MnAs and 847±10 °C. The eutectic consists of the manganese arsenide lattice with ZnSiAs 2 inclusions.

Tetragonal cadmium diphosphide (β-CdP2) single crystals with high structural perfection have been grown and their thermal conductivity has been measured. The results indicate that the higher thermal conductivity across the c axis corresponds to the smaller unit-cell parameter of the crystals (a = 5.08 ± 0.01 A and c = 18.59 ± 0.05 A). The observed thermal conductivity anisotropy is tentatively attributed to the fact that structural basis of β-CdP2 is made up of spectral phosphorus chains running in the [100] and [010] directions.

The transport properties of granular Cd3As2 + MnAs (44.7% MnAs) composite structures have been studied near room temperature at high hydrostatic pressures of up to 9 GPa. The results demonstrate that the composite undergoes a structural phase transition and has a pressure-induced negative magnetoresistance.

Eutectic composites in the InSb–MnSb system have been grown by the Bridgman method in vertical geometry using a growth charge of eutectic composition. The composites consisted of a [110]-oriented single-crystal InSb matrix and single-crystal MnSb needles aligned in the growth direction. As the solidification rate was raised from 0.5 to 6 mm/h, the length of the needles increased, whereas their diameter dropped from 20 to 4 µm. Further raising the solidification rate led to spontaneous crystallization. Characteristically, the electrical and magnetic properties of the eutectic composites in the InSb–MnSb system were found to exhibit large anisotropy. The low-temperature resistivity of the composites across the needles is four to five times that along the needles. With increasing temperature, the resistivity ratio drops by up to a factor of 2–3. This can be accounted for in terms of a geometric factor. The electrical conductivity of the composites is determined primarily by the MnSb phase, whose volume along the growth direction was considerably larger. According to magnetic measurements, the eutectic composites in the InSb–MnSb system are ferromagnets with a Curie temperature of ≃ 600 K.

Three self-assembled nanogranular composites based on MnAs ferromagnetic inclusions embedded in ZnSnAs 2 semiconductors with MnAs concentration 10, 20, 47 mol.% were synthesized. The samples were studied by X-ray, SEM, AFM, MFM and SQUID methods. It has been shown that the increasing of the MnAs concentration in composite leads to slightly increasing of the size of the magnetic inclusions. Their size depends mainly on the speed of the crystallization, but the shape of the inclusions depends on the type of the interaction between materials. The connection between equilibrium and non-equilibrium structure of the compounds has been demonstrated. Magnetic properties of the ZnSnAs 2 + MnAs samples show ferromagnetic phase transition with the Curie temperature having values from 313 K to 336 K, increasing as a function of the MnAs concentration in the nanocomposite. A small paramagnetic signal is observed at low temperatures due to individual Mn ions randomly distributed in the ZnSnAs 2 lattice. All our samples show only a narrow magnetic hysteresis loop except of the sample with 47 mol.% of MnAs, for which the coercive field increases to about 120 G. The carrier transport of the alloy shows significant influence of the MnAs clusters. All our samples have p-type conductivity with magnetotransport strongly influenced by the presence of the MnAs phase in the nanocomposite samples. The magnetoresistance (MR) of the alloy shows a complex behavior. The grain boundaries and MnAs clusters influence on the amplitude, sign, and temperature of MR.

The interest in thorough description of Zn 1– x Mn x GeAs 2 arises from its suitability for application in the field of non-linear optics. The room temperature far-infrared reflectivity spectra of single crystals Zn 1– x Mn x GeAs 2 , where 0 ≤ x ≤ 0.078, were measured in the spectral range from 80 cm −1 to 500 cm −1 . The spectra were analyzed by fitting procedure using a dielectric function which includes interaction between a plasmon and two different phonons. The detected phonons are in excellent agreement with the theoretical predictions. The MnAs cluster phonons are detected, as well.

Zn3As2 + MnAs composite films 0.7–0.9 μm in thickness have been grown on silicon and sapphire substrates by vacuum thermal evaporation. As shown by scanning electron microscopy, the films consisted of spherical grains ranging in size from 5 to 150 nm and had uniform Zn, As, and Mn elemental concentration distributions. The grains were made up of magnetic clusters less than 10 nm in size, as determined by atomic force microscopy, magnetic force microscopy, and small-angle X-ray scattering.

Six equilibrium samples of (1 − x )ZnSnAs 2 + x MnAs ( x = 0, 0.1, … 0.5 mol.%) and one quenched sample of 0.8ZnSnAs 2 + 0.2MnAs were synthesized. The samples were studied with X-ray, DTA, MFM and SEM. The system ZnSnAs 2 –MnAs has eutectic point with coordinates 45 ± 2 mol.% MnAs and 744 ± 10 °C. The eutectic compound contains isolated, practically round shape inclusions of MnAs in the host ZnSnAs 2 . Based on the earlier investigations, we predict negative magnetoresistance effect in this semiconductor–ferromagnet compound with nanogranular structures. The lattice parameters of ZnSnAs 2 without manganese arsenide and ZnSnAs 2 + MnAs are similar, meaning MnAs does not influence the lattice parameters. Therefore one can make conclusion that solubility of the MnAs in ZnSnAs 2 is low. The lattice parameters are a = 5.8509 A, c = 11.7135 A for tetragonal and a = 5.8558 A for cubic symmetry. The density of the ZnSnAs 2 calculated from the HR-XRD is 5.5314 g/cm 3 for tetragonal and 5.5230 g/cm 3 for cubic structure.

Eutectic GaSb + MnSb films ranging in thickness from 80 to 130 nm have been grown on sapphire substrates by pulsed laser deposition using mechanical droplet separation. The films were similar in composition to the ablation target, consisting of the eutectic GaSb-MnSb alloy. According to atomic force and electron microscopy data, the films were homogeneous, with p-type conductivity. Their electrical properties depended significantly on deposition conditions. The best films had a resistivity of 7 × 10−3 Ω cm, carrier concentration of 8.1 × 1019 cm−3, and carrier mobility of 102 cm2/(V s). Characteristically, the films had a negative magnetoresistance. Their magnetization curves showed saturation in a magnetic field of ∼1 × 10−1 T. According to the magnetic-field dependences, the coercive force in the films was within 3 × 10−2 T; that is, the films were soft magnets with a small domain size.

The phase equilibria in the ZnGeAs 2 –CdGeAs 2 system were investigated by X-ray, DTA, EDXRF, microstructure observations and SEM. The solid solutions are present in all range of concentrations above 440 °С. Below this temperature a decay region of solid solution of Zn 1− x Cd x GeAs 2 is observed in the range of concentrations x = 0.19–0.92 at room temperature. The investigation of the system was obstructed by liquation and segregation processes occurring during the synthesis.

We have measured the resistivity and relative bulk compressibility of Zn1 − xMnxGeAs2 (x = 0.02 and 0.4) samples at hydrostatic pressures of up to 9 GPa. The pressure dependences of the resistivity and relative compressibility demonstrate sharp changes in resistivity and volume. The changes occur at the same high pressure, attesting to a structural phase transition.

Currently, complex ferromagnetic semiconductor systems are of significant interest due to their potential applicability in spintronics. A key feature in order to use semiconductor materials in spintronics is the presence of room temperature ferromagnetism. This feature was recently observed and is intensively studied in several Mn-alloyed II-IV-V2 group diluted magnetic semiconductor systems. The paper reviews the origin of room temperature ferromagnetism in II-IV-V2 compounds. In view of our recent reports the room temperature ferromagnetism in Mn-alloyed chalcopyrite semiconductors with more than 5 molar % of Mn is due to the presence of MnAs clusters. The solubility of magnetic impurities in bulk II-IV-V2 materials is of the order of a few percent, depending on the alloy composition. High values of the conducting hole - Mn ion exchange constant Jpd have significant value equal to 0.75 eV for Zn0.997Mn0.003GeAs2. The sample quality has significant effect on the magnetotransport of the alloy. The magnetoresistance of the alloy change main physical mechanism from spin-disorder scattering and weak localization for homogeneous samples to cluster-related geometrical effect observed for nanocomposite samples. The magnetoresistance of the II-IV-V2 alloys can be then tuned up to a few hundreds of percent via changes of the chemical composition of the alloy as well as a degree of disorder present in a material. [Projekat Ministarstva nauke Republike Srbije, br. III45003]

We have studied the key features of the chemical bonding in hexagonal and rhombohedral antimony and determined polymorphism boundaries that would allow one to extend technological potentialities of creating novel antimony-based materials.

We have synthesized a new ferromagnetic material based on a Zn3P2 + MnP composite with a Curie temperature of 290 K. Experimental data demonstrate that its magnetic and electrical properties are determined by manganese phosphide nanoclusters. The composite has metallic conductivity. Its electrical resistance drops with increasing magnetic field, and its magnetoresistance in a magnetic field of 14 T at 7 K reaches 9%.

Optical properties of p-type Zn1−xMnxGeAs2 for 0 ⩽ x ⩽ 0.078 were investigated by Raman spectroscopy at room temperature. Phonons of ZnGeAs2 are experimentally determined and they are in excellent agreement with those theoretically predicted. Existence of MnAs clusters was confirmed in the sample with the highest concentration of Mn. MnAs was found in α and β phases and their vibrational frequencies are obtained experimentally. Plasmon – two different phonons interaction in Zn1−xMnxGeAs2 is registered and analyzed.

The resistivity (ρ) and Hall coefficient (RH) of n-Cd1 − xCoxGeAs2 with x = 0.05–0.15 were measured as functions of temperature (at atmospheric pressure) and pressure (up to p = 7 GPa). The temperature-dependent ρ data were used to determine the ionization energy of a cobalt-related impurity center. In the ρ(p) and RH(p) curves, we identified structural semiconductor-semiconductor phase transitions under both increasing and decreasing pressure. Using a mixed-phase structure-effective medium model, we assessed the dynamics of the variation of phase composition with pressure.

The structural and magnetic phase transitions and magnetoresistance of the diluted magnetic semiconductors Cd1 − xMnxGeAs2 and Cd1 − xMnxGeP2 have been studied at high hydrostatic pressures, up to 7 GPa. The normal and anomalous Hall coefficients of the samples have been determined graphically from experimental data.

The theory of elasticity and lattice dynamics are used to analyze the key features of chemical bond formation in cadmium. The results increase the possibilities of finding appropriate technological solutions.

The magnetic properties of a Cd1−xMnxGeAs2: MnAs hybrid micro-composite have the signature of ferromagnetic order at room temperature. Magnetotransport reveals the presence of a large linear positive magnetoresistance, with maximum values of about 550% ( B = 22 T) for x = 0.028 . This is interpreted in terms of an effective medium approximation with the value and the shape of the magnetoresistance depending on the structural and electronic properties of the semiconductor rather than on its magnetic properties. The absence of an anomalous Hall effect leads to the conclusion that ferromagnetic ordering is not the only factor necessary for the occurrence of asymmetric scattering in granular ferromagnetic materials.

This review describes the principles of semiconductor spintronics, represents the physicochemical properties of materials based on manganese-alloyed AIIBIVC 2 V compounds, considers the results from theoretical simulation of magnetic properties of AIIBIVC 2 V alloyed with 3d metals, summarizes the basic approaches to explanation of ferromagnetism with Curie points above room temperature arising in AIIBIVC 2 V :Mn, and indicates promising ways to synthesize and study magnetic semiconductors based on chalcopyrites AIIBIVC 2 V in order to produce a suitable material for spintronic devices.

The ferromagnetic semiconductor Cd0.7Mn0.3GeAs2 undergoes a high-pressure ferromagnetic-to-antiferromagnetic phase transition. We have studied this transition at different temperatures. From magnetic-field dependences of the Hall resistance measured at different temperatures, we have derived the normal and anomalous Hall coefficients of the material as functions of temperature. Its transverse magnetoresistance changes from positive to negative near the ferromagnetic-to-antiferromagnetic phase transition.

Structurally perfect CdAs2, ZnAs2, Cd1 − xZnxAs2, and Zn1 − xCdxAs2 single crystals have been grown, and the main parameters of their band structure have been determined. We have proposed band structure models for the crystals and presented evidence in favor of the models of structural defects responsible for the donor and acceptor levels in CdAs2, ZnAs2, Cd1 − xZnxAs2, and Zn1 − xCdxAs2.

Chemical bonding theory is used to examine fine details of the melting and crystallization behaviors of CdSb, ZnSb, and CdSb-ZnSb solid solutions and to identify conditions for the preparation of these materials with tailored properties.

The Si-ZnAs2 pseudobinary join of the Zn-Si-As system has been studied using physicochemical characterization techniques. It contains a congruently melting compound of composition ZnSiAs2 and has two eutectics: Si-ZnSiAs2, at 55 mol % Si + 45 mol % ZnAs2, with the melting point at 1010°C, and ZnSiAs2-ZnAs2, at 93 mol % ZnAs2 + 7 mol % Si, melting at 730°C. The solubilities of the end-members in ZnSiAs2 are within 1 mol %.

The electrical resistivity and Hall coefficient of oriented single-crystal p-Cd1 − xMnxGeAs2 samples have been measured at high pressures. The results indicate that the crystals undergo a reversible structural transformation at 5.5 GPa, which is independent on the sample orientation.

The first data are presented on the band structure of monoclinic Zn1 − xCdxAs2 crystals. The fundamental absorption edge of Zn1 − xCdxAs2 for the E ‖ c polarization is shown to be dominated by an indirect allowed transition for absorption coefficients α‖ 6 cm−1, both transitions involving excitonic levels. The absorption edge for E ⊥ c is due to a direct forbidden transition with the participation of excitonic levels. We have determined the band gap values for these transitions in the temperature range 80–300 K, the exciton binding energy, and the ionization energies of four deep acceptor levels produced in the band gap by structural defects.

The transmittance of Zn1−x Cd x As2 anisotropic single crystals in their transparency region is found to depend on the incident light polarization, photon energy, and sample thickness. This effect is shown to be associated with light scattering in Zn1−x Cd x As2, which can be understood in terms of the crystal structure of the monoclinic crystals. The fundamental absorption edge in Zn1−x Cd x As2 is dominated by an indirect forbidden transition for the E ‖ c polarization and by a direct forbidden transition for E ⊥ c.

The electrical resistivity and Hall coefficient of Cd1−xMnxGeP2 (x=0−0.19) have been measured at 300 K and hydrostatic pressures of up to 5 GPa. The results indicate that CdGeP2 dissociates to CdP2 and Ge at p = 3.2 GPa, while the incorporation of manganese stabilizes the crystal structure of CdGeP2, and Cd0.81Mn0.19GeP2 undergoes a reversible phase transition at p = 3.5 GPa.

The transmittance of β-ZnP2 crystals is measured as a function of the incident light polarization, photon energy, and sample thickness over the transmission window of the crystals. The results attest to anomalous light propagation through β-ZnP2, which is attributable to refractive-index nonuniformity. The intrinsic edge in β-ZnP2 for the E ∥ c polarization is shown to be dominated by indirect and direct allowed transitions for α below and above 1 cm−1, respectively. The 300-K indirect band gap of β-ZnP2 is evaluated.

Structurally perfect NiSb single crystals ≃25 mm in diameter and 250 mm in length were grown by the Bridgman method. Polishing etch compositions were selected for the preparation of NiSb substrate surfaces.

The impurity photoconductivity spectra of undoped Cd1 − x Zn x As2 single crystals with x ≤ 0.06 are measured in the range 85–300 K. The results are used to determine the ionization energies of donor and acceptor levels produced in the crystals by structural defects: ɛd ≈ 0.019, 0.26, and 0.42 eV; ɛa = 0.24 and 0.34 eV, respectively. The nature of the structural defects responsible for these levels is discussed.

Single crystals of the Zn0.97Cd0.03As2 solid solution are prepared, and their structure is determined by x-ray diffraction. The incorporation of Cd into ZnAs2 has no effect on its lattice parameters (to within the error of determination). Cd is shown to occupy interstitial sites in the solid solution.

Optically homogeneous single crystals of tetragonal cadmium diphosphide (β-CdP2) are prepared by vapor-phase growth, and their electrical conductivity, dielectric permittivity, and loss tangent are measured during slow heating from 78 to 400 K in the [001] and [100] directions at frequencies of 102, 103, 104, and 106 Hz. The permittivity of the crystals increases with temperature. The electrical properties of β-CdP2 are shown to be anisotropic.

Large, perfect CdGeAs2 single crystals doped with 0.006, 0.49, and 0.89 wt % Mn are grown by the Bridgman method. The Mn concentration in the crystals is determined by atomic absorption spectrophotometry. X-ray diffraction results indicate that Mn doping influences the bond distances in CdGeAs2 and its lattice parameters. Based on the observed structural changes, a model is proposed for the Mn incorporation into the structure of CdGeAs2.

The optical absorption, photoconductivity, and short-circuit photocurrent spectra of structurally perfect Cd1 - x ZnxAs2 (x = 0.03, 0.05, 0.06) single crystals are studied for the first time near the intrinsic edge in the range 80–300 K. The results demonstrate that the intrinsic edge in the solid solutions is due to indirect transitions involving the formation of excitons for both the E ‖ c and E ⊥ c polarizations. The indirect gaps ɛ g i of the solid solutions are determined. In the range 80–300 K, the data for x = 0–0.06 and both polarizations are well fitted by ɛ g i (x) = ɛ g i (0) + 0.0866x + 2.35x 2. The introduction of 6 mol % ZnAs2 into CdAs2 increases its ɛ g i ≃ by 14 meV.

Pressure-dependent resistivity and Hall effect measurements indicate that p - type Cd1 - xMnx GeAs2 solid solutions with x = 0.06 and 0.18 undergo a high-pressure semiconductor-metal transition. The characteristic points of the phase transition are located, and its dynamics is analyzed in terms of the theory of mixed-phase systems.

The initial stages of the formation of CdAs2-ZnAs2 solid solutions are analyzed in terms of crystalchemical energetics. Given that the bond enthalpies decrease in the order H (Zn-As)< H (Cd-As)< H (As-As), it is concluded that, most likely, CdAs2-based solid solutions are substitutional and ZnAs2-based solid solutions are interstitial, and that the thermochemical stability of the substitutional solid solutions is higher than that of CdAs2 . The conclusions drawn from crystal-chemical analysis correlate with the reported x-ray diffraction, chemical analysis, resistivity, and Hall data for the solid solutions.

Cd1 – x Zn x As2 (x = 0.03, 0.05, 0.06) single crystals are grown by the Bridgman method, and their optical absorption spectra are measured. The introduction of Zn is shown to increase the band gap of CdAs2, by up to ≃14 meV at x = 0.06. The highest content of ZnAs2 incorporated into CdAs2 is 6 mol %.

Data are presented on the chemical bonding in CdSb and the synthesis of CdSb-based materials for novel optical, thermoelectric, and other devices.

Phase relations along the Cd3As2–ZnAs2 and Zn3As2–CdAs2 joins are studied by differential thermal analysis, x-ray diffraction, and microstructural analysis. The results, in conjunction with earlier data on the CdAs2–ZnAs2, Zn3As2–Cd3As2, Cd3As2–CdAs2, and ZnAs2–Zn3As2 binaries, are used to map out the phase diagram of the liquidus surface in the composition region Zn3As2–ZnAs2–CdAs2–Cd3As2 of the ternary system Cd–As–Zn. The ternary eutectic revealed in this region has an approximate composition of 26 at. % Cd + 65 at. % As + 9 at. % Zn and melts at 863 K.