Zinc blende lattice

Crystalline form cubic close pack (zinc blende) Lattice parameters a = 0.56531 O.nm... 

Aluminium phosphide crystallises in a zinc blende lattice Both... 

Cubic zinc blende lattice (e.g., precipitated CdS), spinel lattice (e.g., Fe304, CoA1204)... 

The luminescent properties can be influenced by the nature of the activators and coactivators, their concentrations, the composition of the flux, and the firing conditions. In addition, specific substitution of zinc or sulfur in the host lattice by cadmium or selenium is possible, which also influences the luminescent properties. Zinc sulfide is dimorphic and crystallizes below 1020 °C in the cubic zinc-blende structure and above that temperature in the hexagonal wurtzite lattice. When the zinc is replaced by cadmium, the transition temperature is lowered so that the hexagonal modification predominates. Substitution of sulfur by selenium, on the other hand, stabilizes the zinc-blende lattice. 

Figure 6. Top, diamond lattice (Si) bottom, zinc blende lattice (GaAs). (Reproduced with permission from reference 8. Copyright 1985 Wiley.)...

If half of the nickel atoms in Figure 3.26a are removed, the half-Heusler ABC structure of Figure 3.26b is obtained. In the half-Heusler strucmre, each atom still resides on a cesium-chloride lattice site. The rock-salt component (B and C) remains intact, but the A atoms form a zinc blende lattice with B and C. Examples of compounds with this structure include MnNiSb, AuMgSn, BiMgNi, and RhSnTi. 

The interstitial sites of a diamond or zinc blend lattice are usually vacant. The probability of an interstitial atom finding an available site to jump into is very high. As it jumps from one site to another, it faces a constriction due to the host atoms (see Fig. 9.11a) the jumping atom needs a little push to squeeze by. This situation is described as having an activation or energy barrier. In this case the barrier is also periodic in the lattice. 

This section draws attention to some of the common structure types adopted by semiconductors. The diamond-type network (often referred to an adamantine solid structure) is adopted by Si and Ge the addition of dopants occurs without structural change. Related to this network is the zinc blende lattice and among compounds adopting this structure are GaAs, InAs, GaP, ZnSe, ZnTe, CdS, CdSe,... 

Gallium arsenide is an important semiconductor and crystallizes with a zinc blende lattice (see Figure 5.18b). Slow hydrolysis occurs in moist air and protection of semiconductor devices from the air is essential N2 is often used... 

It was established by x- ray structure analysis that the phase having the composition InAsTe has the zinc-blende lattice with a constant of 6,13 A. 

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. 

Fig. 4.1 -2 The zinc blende lattice (a is the lattice parameter). This is a diamond lattice in which the two elementary cubes are occupied by different atomic species, for example by Zn-ions and by S-ions of opposite charge. Each Zn-ion is surrounded tetrahedrally by four nearest neighbour S-atoms and vice versa...

Fig. 4.1-23 Brillouin zone of the diamond and of the zinc blende lattice...

Fig. 4.1-130 The wurtzite lattice (a and c are the lattice Fig. 4.1-131 The zinc blende lattice (a is the lattice param-...

Zinc sulfide ZnS 45.358 352 77 Zinc blende lattice, 6>d calculated from Cp... 

Although the eommon semieonduetor materials share this basie diamond/zinc blende lattiee strueture, some semieonduetor erystals are based on a hexagonal elose-paeked (hep) lattice. Examples are CdS and CdSe. In this example, all of the Cd atoms are located on one hep lattice whereas the other atom (S or Se) is located on a second hep lattice. In the spirit of the diamond and zinc blende lattices, the complete lattice is constructed by interpenetrating these two hep lattices. The overall crystal structure is called a wurtzite lattice. Type IV-VI semiconductors (PbS, PbSe, PbTe, and SnTe) exhibit a narrow bandgap and have been used for infrared detectors. The lattice structure of these example IV-VI semiconductors is the simple cubic lattice (also called an NaCl lattice). 

Our further assumption is that the dielectric permittivity e may be treated as scalar. This assumption is valid for aU semiconductors with diamond and zinc-blende lattice [342, 343]. 

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