InAs/GaAs

The Sii., Gev/Si quantum well can be prepared by People et al. (52) or Kruek et al. (53). Their products can be applied to the quantum well infrared photodetectors. Similar intraband absorption in the mid-infrared can be achieved by the self-assembled InAs/GaAs as well (54,55). 

Leem, J.-Y., Jeon, M., Lee, J. el al. (2003) Influence of GaAs/InAs quasi-monolayer on the structural and optical properties of InAs/GaAs quantum dots. Journal of Crystal Growth, 252(4), 493-98. 

Similarly, the covalent compound ZnS (zinc blende) is a semiconductor that has a structure similar to diamond, where the Zn atoms occupy the FCC lattice sites, and the S atoms occupy four of the eight tetrahedral sites of the FCC lattice (see Section 1.2.2). Analogous semiconducting properties are obtained when elements from the IIIA and VA columns of the periodic table are formed, for example, InAs, GaAs, and InP and also in the case when elements from the IIB and VIA columns of the periodic table are created, for instance, ZnTe and ZnSe. 

Mitsuru Sugawara, Theoretical Bases of the Optical Properties of Semiconductor Quantum Nano-Structures Yoshiaki Nakata, Yoshihiro Sugiyama, and Mitsuru Sugawara, Molecular Beam Epitaxial Growth of Self-Assembled InAs/GaAs Quantum Dots... 

Adler F., Geiger M., Bauknecht A., Scholz F. and Schweizer H. (1997), Intrinsic carrier relaxation and the exciton lifetime in InAs/GaAs quantum dots , Phys. Status SoUdi A 164, 431 36. 

Lee H., Yang W., Lowe-Webb R. and Sercel P. C. (1998), The shape of InAs/GaAs quantum dots relation to optical properties , in Gershoni D., ed., Proc. 24th. Int. 

Yang W., Lee H., Johnson T. J., Sercel P. C. and Norman A. G. (2000), Electronic structure of self-organized InAs/GaAs quantum dots bounded by 136 facets , Phys. Rev. B 61, 2784-2793. 

Arsenic from the decomposition of high purity arsine gas may be used to produce epitaxial layers of III—V compounds, such as InAs, GaAs, AlAs, etc, and as an -type dopant in the production of germanium and silicon semiconductor devices. A group of low melting glasses based on the use of high purity arsenic (24—27) were developed for semiconductor and infrared applications. 

In InAs/GaAs multilayers, Nakata et al. [7] have shown, from RHEED, that the InAs critical thickness in upper layers was smaller than that of the first layer. However, these authors have not clearly established whether such a decrease of the InAs critical thickness was due to the strain induced by underlying layers or surface migration of In atoms. Similar results have been observed in the Ge/Si system by Schmidt et al. [9, 10]. However, as such measurements were done by means of TEM microanalysis in postgrown samples, no proposal to improve the island size homogeneity has been submitted. 

Figure 5. Schematic view of an InAs/GaAs nanotubes (left) and energy positions of the conduction- (1) and valence-band (2) edges in the tube walls, and the position of the electron (3) and hole (4) energy levels.

In the case of these compounds, dissociation into components is the rule. Nevertheless, using flash evaporation for example AlSb [307, 308] GaAs [309] and InSb [310] or specific recombination as with the so-called three-temperature method [311], e.g. (InSb, InAs, GaAs and also the compounds 2 and CdSe [312, 313], a stoichiometric film deposition can also be achieved. Moreover, three-component films, such as GaAsxP].x can be produced in this way [314]. With the three temperature method, the single components of a compound are separately evaporated each from one source. The concentration of each component in the vapour phase is adjusted via the relevant source temperature. With a suitable substrate temperature, condensation and stoichiometric compound formation can now be achieved, for example in such a way that the Sb atoms which do not react with the In atoms to InSb on the substrate surface are re-emitted into the vapour phase. 

An important group of functional materials is formed by the III-V compounds, e.g. InSb, InAs, GaAs, which have found applications in electronics and in thermoelectric power generation (C. S. Roberts, 1967 Cadoff, 1967). The constitutive ele-... 

Fry, P.W., Itskevich, I.E., Mowbray, D.J., Skolnick, M.S., Finley, J.J., Barker, J.A., et al., 2000. Inverted electron-hole alignment in InAs-GaAs self-assembled quantum dots. Phys. Rev. Lett. 84, 733. 

Metal catalysis - organic solvents Short InP, InAs, GaAs microfibers 2.3 [18]... 

Fig. 3.2 InAs coverage dependence of RHEED diffraction-beam intensity in InAs/GaAs hetero-epitaxy, critical thickness for growth mode transition was about 1.75 ML. RHEED pattern changed from streak to spot pattern at the critical thickness...

Self Size-Limiting Growth of Uniform InAs/GaAs Quantum Dots... 

Figure 3.21 shows (110) cross-sectional STEM images of InAs QDs, annealed at 700°C for Omin (Fig.3.21a), 40min (Fig.3.21b), and 80min (Fig.3.21c). From Fig. 3.21a-c the lateral size (L) of the QDs, the thickness of the wetting layer (W), and the total height (D) were measured, and the results are plotted in Fig. 3.22 as a function of annealing time. Broadening of the InAs/GaAs heterointerface due...

On the other hand, low QD density is desirable for some devices that use individual QDs, such as single-photon sources. However, precise control of low-density QDs is difficult because the growth mode transition from 2D to 3D occurs rapidly. To realize low-density growth, the surface concentration of adatoms should be suppressed, and the supply amount of growth materials should be precisely controlled. In Sect. 3.5.2, an intermittent growth method is presented for the controlled formation of low-density InAs/GaAs QD. 

A QD array structure enables electronic and optical interaction between neighboring QDs. Recently, exciton interactions between QDs have become desirable for certain novel devices [42]. In normal SK growth, the 3D islands are randomly deposited on a surface. However, the self-formation of arranged QDs can be achieved by modification of the underlying layers. In this section, the self-arrangement of vertical and in-plane InAs/GaAs QDs is described. 

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