ZnS, ZnSe, ZnTe

Equilibria considerations on solution-grown zinc chalcogenide compounds have been put forward by Chaparro [28] who examined the chemical and electrochemical reactivity of solutions appropriate for deposition of ZnS, ZnSe, ZnTe (and the oxide ZnO) in order to explain the results of recipes normally used for the growth of such thin films. The author compared different reaction possibilities and analyzed the composition of solutions containing zinc cations, ammonia, hydrazine, chalcogen anions, and dissolved oxygen, at 25 °C, by means of thermodynamic diagrams, applicable for concentrations usually employed in most studies. 

Fig. 7.24 Experimental isomer shifts of Ga/XY sources (XY = ZnO, ZnS, ZnSe, ZnTe, MgO) relative to ZnO as absorber at 4.2 K are plotted against the lattice spacing parameter (Mav/p) (from [55]). The isomer shift for MgO was taken from [61]...

Bernard, J. E., and A. Zunger (1987). Electronic structure of ZnS, ZnSe, ZnTe and their pseudobinary alloys. Phys. Rev. B36, 3199-228. 

Eckelt, P. (1967). Energy band structures of cubic ZnS, ZnSe, ZnTe and CdTe (Korringa-Kohn-Rostoker method). Phys. Status Solidi 23, 307-12. Edwards, A. H., and W. B. Fowler (1985). Semiempirical molecular orbital techniques applied to silicon dioxide MIND03. J. Phys. Chem. Solids 46, 841-57. 

Among compounds of this type, zinc blende and wurtzite structures often occur viz, (BeS, BeSe, BeTe, ZnS, ZnSe, ZnTe, CdS, CdSe, GdTe, HgS, HgSe, HgTe, MgTe, AIN, AlP, AlAs, AlSb, GaP, GaAs, GaSb). In these structures where the coordination number is 4, the bond is predominantly covalent, as we have seen previously. 

ZnS ZnSe ZnTe CdS CdSe CdTe HgS HgSe HgTe... 

The zinc blende lattice Is named after its parent compound, ZnS. Zinc sulfide also exists in a different structure known as the wurtzite lattice. Molecules that can exist in more than one type of crystalline form exhibit polymorphism. The wurtzite lattice is comprised of one type of ion forming a hexagonal closest-packed unit cell, with the other type of ion occupying half of the tetrahedral holes. The following molecules can assume the wurtzite lattice ZnO, ZnS, ZnSe, ZnTe, BeO, Agl, CdS, MnS, SiC, AIN, and NH4F. Both types of lattices consist of corner-shared tetrahedrons, but the tetrahedrons in wurtzite are canted in alternating layers. 

The compounds by the atoms in the groups II-VI like ZnS, ZnSe, ZnTe, CdTe, HgSe, HgTe, CdS, CdSe, and MgTe also possess semiconductor proprieties. As in the case of the III-V compounds a large number of semiconducting alloys may also be realized from the II-IV compounds such as (Hg,Cd)Te, Zn(S,Se), Cd(S,Se), etc. 

Colleti LP, Thomas S, WUmer EM, Stickney JL (1997) Thin layer electrochemical studies of ZnS, ZnSe, and ZnTe formation by Electrochemical Atomic Layer Epitaxy (ECALE). Mater Res Soc Symp Proc 451 235. 

Griesinger et al. [56] recorded Zn Mossbauer spectra with sources of Zn diffused into ZnO, ZnS (both wurtzite and sphalerite), ZnSe, ZnTe, and Cu, and an enriched ZnO absorber. The isomer shifts extracted from their spectra cover a velocity range of 112 pm s and were found to follow linearly the lattice spacing parameter where p and Mav are the host density and average... 

The approach in question allows one to produce a wide range of device structures for opto- and acoustoelectronics, e.g. ZnO/ZnSe, ZnS/ZnSe, CdS/CdSe, and ZnO/ZnTe, with variable parameters. For example, ZnO layers grown on ZnSe may be both n- and / -type. 

Dec et al. 1993, Wu 1998). The NMR spectra of all the zinc chalcogenides (ZnS, ZnSe and ZnTe) have been determined, showing that static Zn lineshapes of the hexagonal forms contain a CSA contribution (Bastow and Stuart 1988). 

MAR/GOL] De Maria, G., Goldfmger, P., Malaspina, L., Piacente, V., Mass-spectrometric study of gaseous molecules ZnS, ZnSe and ZnTe, Trans. Faraday Soc., 61, (1965), 2146-2152. Cited on page 260. 

Several techniques have been reported and, at the present time, the vapor phase deposition processes operating at temperatures around 300 °C are the most used. Thus II-VI compounds films like CdS, CdSe, CdTe, ZnS, ZnSe, and ZnTe have been grown epitaxially on Si, InP, GaAs, GaP, by molecular beam epitaxy (MBE) [204-207], by metal organic chemical vapor deposition (MOCVD) [208-210], or by pulsed laser deposition [211, 212]. Epitaxial deposition from aqueous solutions at low temperatures (< 100 °C) represents another approach. Specific beneficial effects may be also expected due to the simplicity of the process involving low cost investments. On the other hand the low temperature has for consequence the absence of interdiffusion processes around interfaces and the interfacial properties of the solids in contacts with solutions implicate excellent coverage properties at low thicknesses. Different... 

S.h.f.s. are observed (208, 662) in F , S, Se , and Te crystals and in all cases are attributable to interaction with first and, in some cases, second sphere coordination of the anion (see Table XXXIII). In ZnS, S splittings are observed, a rare event since the isotope is only in 0.74% natural abundance. The decrease in Ag (g — 2.0023) and in Cr h.f.s. in the series of host lattices ZnS, ZnSe, and ZnTe follows the order of increase in covalency as expected. There are no paramagnetic chemical compounds of Cr+ with 8 =. ... 

Use of the alternative methods whose selection rules admit of spectral activity of the LO modes. One such method is polarized Raman spectroscopy, which is applicable to substances with cubic zinc blend and hexagonal wurtzite structures such as ZnS, ZnSe, CdS, ZnO, ZnTe, and the III-V compounds (see Refs. [47-49] and literature cited therein). The most direct method to measure vlo is inelastic neutron scattering (INS) since there are no selection rules for INS spectroscopy and as a result all modes are allowed [50, 51]. 

Ves S (1991) Band-gaps and phase transitions in cubic ZnS, ZnSe and ZnTe. In Hochheimer HD, Etters RD (eds) Frontiers of high-pressure research. NATO ASI Ser B 286 369-376 Tang Z, Gupta Y (1988) Shock-induced phase transformation in cadmium sulfide dispersed in an elastomer. J Appl Phys 64 1827-1837... 

Similar reactions can be used to produce GaN, GaP, GaSb, the corresponding compounds of A1 and In and also mixed solid solutions. The method can be extended to isoelectronic Group II/VI compounds such as ZnS, ZnSe or ZnTe (Me2Zn-f H2S, H2Se or Me2Te) or Group IV/VI derivatives such as PbY (Y = S, Se, Te). 

Nanostructures (nanocrystals, nanopartides, nanowires, nanorods) are made from semiconductive ZnS, ZnO, ZnSe, ZnTe, HgSe, MgSe, CaSe, SrSe, BaS, BaTe, GaN, GaP, InP, PbS, PbSe, AIS, and AlSb and used as film electrodes. 

This structure can be obtained from the diamond structure by exchanging two carbon atoms with Zn and S atoms, so that the operation of interchange of two atoms in the primitive unit cell disappears. The zincblende structure is known for different compounds (Agl, AlAs, AlP, AlSb, BAs, BN, BP, BeS, BeSe, BeTe, CdS, CuBr, CuCl, CuF, Cul, GaAs, GaP, GaSb, HgS, HgSe, HgTe, INAs, InP, MnS, MnSe, SiC, ZnSe, ZnTe). For a=5.4093 A the ZnS structure data are the following ... 

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