Epitaxial films homoepitaxy

Epitaxy is a term that denotes the growth of a thin crystalline film on a crystalline substrate. When the epitaxial film is of the same material as the substrate (for instance silicon on silicon), the process is known as homoepitaxy. When film and substrate are of different... 

It has been widely demonstrated that the preparation of oriented, and in some cases epitaxial films by CSD is possible, despite the relatively large thickness of the films that is deposited in a single step. Lange ° reviewed the various mechanisms that lead to oriented growth, and a variety of factors including reactions at the electrode interface, - organic content within the film," " and the use of seed layers" to promote homoepitaxy have been discussed. The ability to control film properties (remanent polarization, dielectric constant, etc.) through manipulation of film orientation has also been shown. 

When an epitaxial film grows on a substrate of the same nature, one deals with homoepitaxy. If the growth occurs on a different substrate, one deals with heteroepitaxy. 

Epitaxy is defined as the oriented overgrowth of film material and typically refers to the growth of single crystal films. Homoepitaxy is the epitaxial growth of a deposit on a substrate... 

The nature of the deposit and the rate of nucleation at the very beginning of the deposition are affected, among other factors, by the nature of the substrate. A specific case is that of epitaxy where the structure of the substrate essentially controls the structure of the deposit.Plb lP ] Epitaxy can be defined as the growth of a crystalline film on a crystalline substrate, with the substrate acting as a seed crystal. When both substrate and deposit are of the same material (for instance silicon on silicon) or when their crystalline structures (lattice parameters) are identical or close, the phenomena is known as homoepitaxy. When the lattice parameters are different, it is heteroepitaxy. Epitaxial growth cannot occur if these stmctural differences are too great. 

Fundamental to forming high quality structures and devices with thin-films of compound semiconductors is the concept of epitaxy. The definition of epitaxy is variable, but focuses on the formation of single crystal films on single crystal substrates. Homoepitaxy is the formation of a compound on itself. Heteroepitaxy is the formation of a compound on a different compound or element, and is much more prevalent. 

MBE (molecular beam epitaxy), which involves epitaxial growth of thin films on either the same material as substrate (homoepitaxial) or a lattice-matched substrate (heteroepitaxial) the heated substrate reacts with a molecular beam of compounds containing the constituent elements of the semiconductor as well as any dopants the resultant film is essentially a single crystal slow growth rates produce films from a few nanometers thick to at most several hundred nanometers that have very high purity and controlled levels of dopants. 

Epitaxy The deposition of a single-crystal film of a material upon a template of atoms provided by the surface of a crystalline solid called the substrate. Such a film is termed an epitaxial layer If the film and substrate are composed of materials having the same lattice parameter, the film is homoepitaxial," and if the film and substrate are formed from materials with different lattice parameters, the film is heteroepitaxial. ... 

Epitaxial metal deposition — In an epitaxial deposition the crystal lattice of the substrate is continued in the deposit. In homoepitaxy the substrate and the growing film... 

If two crystals are placed side by side, it is possible to define vector relations that express the characteristic crystallographic directions of one of the ctystals in a set of coordinates defined by the cell of the other crystal. These are referred to as epitaxy relations. By extrapolation, when the grains that comprise a polyctystalUne film all have virtually the same orientation, it is possible to define ctystallographic axes specific to this orientation and to find the relation between these axes and those, for example, of the single ctystal on which the film is deposited. If the film and the substrate share the same ctystal nature, we are dealing with homoepitaxy, otherwise, it is referred to as heteroepitaxy. Epitaxy relations are three-dimensional and therefore they are usually written as follows ... 

Diamond homoepitaxy and heteroepitaxy have been achieved on diamond and cBN, respectively. Epitaxially textured and fiber textured, highly oriented diamond films have been grown on Si(lOO). The feasibility of diamond heteroepitaxy on Ni, Ti, Co and Cu has also been confirmed by several experiments. Diamond can grow on Fe, but not yet by epitaxy. 

Molecular beam epitaxy. Epitaxial techniques are techniques of arranging atoms in single-crystal fashion on crystalline substrates so that the lattice of the newly grown film duplicates that of the substrate. If the film is of the same material as the substrate, the process is called homoepitaxy, epitaxy, or simply epi. The most important applications here are Si epi on Si substrates and GaAs epi on GaAs substrates. If the deposit is made on a substrate that is chemically different, the process is termed heteroepitaxy. An important application is the deposition of silicon on an insulator (SOI) e.g. with sapphire (AI2O3) as the insulator in the silicon on sapphire (SOS) process. 

FIGURE 4.4 Radioluminescence and absorption spectra of the 1mm thick plate of undoped ZnO at RT around the band edge. (Ehrentraut, D., Sato, H., Kagamitani, Y. et al.. Fabrication and luminescence properties of single-crystalline, homoepitaxial zinc oxide film doped with tri- and tetravalent cations prepared by liquid phase epitaxy, J. Mater. Chem., 16,3369-3374, 2006. With permission from Royal Society of Chemistry.)... 

Electrochemical atomic layer epitaxy (EC-ALE) is the combination of underpotential deposition (UPD) and ALE. UPD is the formation of an atomic layer of one element on a second element at a potential under, or prior to, that needed to deposit the element on itself [5, 6]. The shift in potential results from the free energy of the surface compound formation. Early UPD studies were carried out mostly on polycrystalline electrode surfaces [7], This was due, at least in part, to the difficulty of preparing and maintaining single-crystal electrodes under well-defined conditions of surface structure and cleanliness [8]. The definition of epitaxy is variable but focuses on the formation of single crystal films on single crystal substrates. This is different from other thin film deposition methods where polyciystalline or amorphous film deposits are formed even on single crystal substrates. Homoepitaxy is the formation of a compound on itself. Heteroepitaxy is the formation of a compound on a different compound or element and is much... 

GaAs films 4 GaN films 3 Ge epitaxy 4 Heteroepitaxial film 1 Heteroepitaxy 1 Homoepitaxy 4... 

Huang Y-P, Zhu S-Y, Li A-Z, Wang J, Huang J-Y, Ye Z-Z (2001) Epitaxial growth of high-quality silicon films on double-layer porous sihcon. Chinese Phys Lett 18(11) 1507 Ito T, Yasumatsu T, Hiraki A (1990) Homoepitaxial growth of silicon on anodized porous silicon. Appl Surf Sci 44 97-102... 

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