Strained semiconductor

The derivations for the strained semiconductors follow closely the classical works of Pikus and Bir " (or refer to for the valence-band). The position vector of a specific atom in the primitive cell in the undeformed crystal is described byr=(x,y,z). The position vector of the same atom in the same primitive cell in the deformed crystal is described byr = (x, y,z ). These two vectors are connected through the strain... 

Gosling, T. J. (1996), The stresses due to arrays of inclusions and dislocations of infinite length in an anisotropic half space Application to strained semiconductor structures. Philosophical Magazine A73, 11-45. 

Nanowalled polymer microtubes fabricated by using strained semiconductor templates. Nanotechnology 2010,27, 245305/1-245305/5. 

Raman Microspectroscopy. Raman spectra of small soflds or small regions of soflds can be obtained at a spatial resolution of about 1 p.m usiag a Raman microprobe. A widespread appHcation is ia the characterization of materials. For example, the Raman microprobe is used to measure lattice strain ia semiconductors (30) and polymers (31,32), and to identify graphitic regions ia diamond films (33). The microprobe has long been employed to identify fluid iaclusions ia minerals (34), and is iacreasiagly popular for identification of iaclusions ia glass (qv) (35). 

The data indicate that elastic shock-compression resistance measurements can provide data on the effects of strain on energy gaps and deformation potentials in semiconductors. Drift mobility measurements on holes in germanium and resistivity measurements on samples with different dopings would appear to be of considerable interest. 

Non-epitaxial electrodeposition occurs when the substrate is a semiconductor. The metallic deposit cannot form strong bonds with the substrate lattice, and the stability conferred by co-ordination across the interface would be much less than that lost by straining the lattices. The case is the converse of the metal-metal interface the stable arrangement is that in which each lattice maintains its equilibrium spacing, and there is consequently no epitaxy. The bonding between the met lic lattice of the electrodeposit and the ionic or covalent lattice of the substrate arises only from secondary or van der Waals forces. The force of adhesion is not more than a tenth of that to a metal substrate, and may be much less. 

Another concept for increasing device speed is the strained layer superlattice (SLS), which consists of alternating layers of semiconductor materials with thickness <10 nm deposited by C VD. These materials have the same crystal structure but different lattice... 

Other forces can arise as a result of elastic strain on the growing film, which can be due to a surface-induced ordering in the first few layers that reverts to the bulk liquid structure at larger distances. This elastic energy is stored in intermolecular distances and orientations that are stretched or compressed from the bulk values by the influence of the substrate at short distances [7]. Similar phenomena are well known to occur in the growth of epitaxial layers in metals and semiconductors. 

Earlier sections of this review have already discussed results for quadrupolar nuclei in certain connections for Knight shifts (Sects. 3.4.3 and 3.4.4), for electric-field (Stark) effects upon NQCCs (Sect. 3.1), for measurements of NQCCs in GaN by static NMR and the effects of strain upon NQCCs (Sect. 3.2.1), for obtaining exchange couplings by MAS-NMR (Sect. 3.2.2), and for characterizing polytypes and defects in cubic polytypes by chemical shifts and NQCCs obtained from MAS-NMR (Sect. 3.3.2). This section will give some further examples of information about semiconductors obtained from the NMR of quadrupolar nuclei (see also [18]). 

Answer. There has been little effective interplay between experimental results obtained on single nanostructures grown as quantum-wells and studied by optical-pumping methods and those obtained on bulk nanoscale semiconductors by more conventional NMR approaches. However, this situation may change, since the former studies can provide information about the effects of, e.g., charge carriers or strain or compositional interfaces upon NMR parameters such as chemical and Knight shifts and EFGs in reasonably well-defined systems. 

---