Ternary Chalcopyrites

Shay, J. L. 1975. Ternary Chalcopyrite Semiconductors Growth, Electronic Properties, and Applications. International Series of Monographs in the Science of the Solid State, Vol. 7. Pergamon, New York. 

Furthermore, the number of tunable sites within the complex allows for their utility in preparing several ternary chalcopyrites of varying composition, in addition to engineering the SSP to match a given spray CVD process (Fig. 6.4). 

Banger, K. K. Cowen, J. E. Hepp, A. F. 2001. Synthesis and characterization of the first liquid single-source precursors for the deposition of ternary chalcopyrite (CuInS2) thin film materials. Chem. Mater. 13 3827-3829. 

Jaffe, J. E. Zunger, A. 1983. Anion displacements and the band-gap anomaly in ternary ABQ chalcopyrite semiconductors. Phys. Rev. B Condens. Matter. 28 5176-5179. 

Ternary semiconductors of the I-III-VI groups (I = Cu, Ag III = Al, Ga, In VI = S, Se, Te) with a chalcopyrite structure have attracted attention as new functional materials for solar hydrogen production [164-167]. With the aim of capturing a larger fraction of solar light, solid solutions of two or more sulfides were prepared. A... 

The analysis of the surface reaction zone has been applied to laboratory-scale PVD of binary and ternary group II-VI compound semiconductors, such as CdS, ZnS, (Cd ZnJS, CdTe, HgTe, and (Cd HgjTe, and the ternary group I-III-VI chalcopyrite CuInSe2 (17). For example, Figure 14 shows the comparison between the predicted and measured compositions of ternary (Zn Cd jS alloys. The predicted composition is within 3 atom % of the measured composition across the range of composition from 10 to 90 atom %. 

Chalcocite forms a limited binary solid solution series (Cu2 S) extending into the ternary diagram beyond a composition of bornite. The central portion of the system is dominated by the biconvex chalcopyrite stability field. Pyrrhotite displays binary as well as ternary solid solubility, in both cases >4 wt.%, whereas pyrite has... 

J.L. Shay, J.H. Wernick, Ternary Chalcopyrite Semiconductors (Pergamon, Oxford, 1975)... 

The most prevalent ternary chalcopyrite materials are p-type Cu(In Ga)(S Se)2 (CIGS), which crystallize in the tetragonal chalcopyrite stmcture and are used in the photovoltaic modules. The complexity of the phase diagrams for Cu-III-VI materials results in a large number of intrinsic... 

The diversity in structure and bonding possible for phosphides is effectively demonstrated by the monophosphides. Monophosphides MP of the group 1 and 2 elements (El, E2) are polyphosphides with i(P ) chains and P2" dumbbells, respectively. Ell and E12 monophosphides are not known. The E3 and E13 monophosphides are the so-called normal compounds with 3x = (M) (see Section 2). With El3, they form the zinc blende structure with tetrahedral heteroatomic bonds. Ternary derivatives such as MgGeP2 and CuSi2P3 have a random distribution of the M atoms, whereas CdGeP2, crystallizes in the ordered chalcopyrite type with a TO[GeP4/2] tetrahedral net (see Section 6.4). The E3 monophosphides form the NaCl structure. CeP is remarkable because of its physical properties (metal-semiconductor transition heavy-fermion behavior). The E14 monophosphides show the break usually observed when passing the Zintl border. Binary lead phosphides are not known SiP and GeP... 

When the compound formation step is performed in the gas phase, as in ILGAR, the end product is less mobile and therefore more homogeneously distributed over the surface. Very thin continuous layers can therefore be prepared in this way, as shown by Muffler et al. (2002). In their work one or more metallic components are deposited from solution on the substrate and then converted to the semiconductor compound by exposure to a reactant gas. The method is able to produce extremely thin coatings of chalcopyrite, chalcogenide and oxide semiconductors on nearly arbitrarily shaped substrates, including very deep nanoporous structures. A number of binary and ternary compounds, such as CdS, ZnS, CulnSa, In2Sc3, ZnO, ZrOa, 263 and others, have been prepared. 

There has been a recent increase in studies of the formation of CuInSej and related chalcopyrite compounds, as they appear to be good candidates for the formation of photovoltaics. Electrochemical formation of a ternary compound presents additional problems, such as increased problems with stoichiometry. 

Other ternary sulfides with a definite composition have been reported, such as CuInS2 [104] which belongs to the important family of chalcopyrite semiconductors. 

The in situ interface conditioning of p-lnP by photoelectrochemical processes, described in Section 2.4.2, is a key procedure for the preparation of efficient and stable photovoltaic and photoelectrocatalytic solar cells and surface analyses wiU be presented that describe the induced chemical and electronic changes. The ternary chalcopyrites CulnSe2 and CulnS2 have meanwhile been developed for use in commercially available solid-state solar cells. For the sulfide-based cell, the use of a toxic KCN etch step of Cu-rich CulnS2 to remove Cu-S surface phases is considered as deleterious for wide-scale application and an electrochemical method will be presented in Section 2.4.3 that replaces the chemical etching procedure. 

Figure 2.71 Structural arrangement of Cu, In, and S or Se atoms in ternary chalcopyrites large gray circles. In smaller light gray circles, Cu small dark gray circles S, Se.

The selection made covers the first efficient and stable system based on the ternary chalcopyrite CulnSe2, an electrochemical treatment to avoid a toxic etching step in solid-state CIS device fabrication, the first stable and efficient liquid-junction solar cell (InP), and a novel concept where nanoemitters, interspersed in a nanoporous passivating film, are used to scavenge excess minority carriers. 

Shay, J. L. and Wemick, J. H., Ternary Chalcopyrite Semiconductors Growth, ElectronicProperties, andApplications, Pergamon Press, 1975. Bergman, R., Thermal Conductivity in Solids, Clarendon, Oxford, 1976. 

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