Application molecular beam epitaxy

In practical applications, gas-surface etching reactions are carried out in plasma reactors over the approximate pressure range 10 -1 Torr, and deposition reactions are carried out by molecular beam epitaxy (MBE) in ultrahigh vacuum (UHV below 10 Torr) or by chemical vapour deposition (CVD) in the approximate range 10 -10 Torr. These applied processes can be quite complex, and key individual reaction rate constants are needed as input for modelling and simulation studies—and ultimately for optimization—of the overall processes. 

Recent applications of e-beam and HF-plasma SNMS have been published in the following areas aerosol particles [3.77], X-ray mirrors [3.78, 3.79], ceramics and hard coatings [3.80-3.84], glasses [3.85], interface reactions [3.86], ion implantations [3.87], molecular beam epitaxy (MBE) layers [3.88], multilayer systems [3.89], ohmic contacts [3.90], organic additives [3.91], perovskite-type and superconducting layers [3.92], steel [3.93, 3.94], surface deposition [3.95], sub-surface diffusion [3.96], sensors [3.97-3.99], soil [3.100], and thermal barrier coatings [3.101]. 

Optoelectronics is a relatively new and fast-growing industry with many applications. Thin-film processes, such as reactive sputtering, molecular-beam epitaxy (MBE), and particularly MOCVD, play a major part in their production. Equipment and materials are similar to those used in the semiconductor industry and many companies manufacture both types of products. In fact the distinction between the two areas is often blurred. Statistics generally do not single out optoelectronics as such and, for that reason, it is difficult to define the scope of the industry accurately. 

Another evaporation technique is molecular beam epitaxy (MBE). MBE produces extremely pure and very thin films with abrupt composition changes and is being considered for extremely exacting electronic and optoelectronic applications. PI However, the deposition rate is very slow and the process is still considered experimental. 

R. F. C. Farrow, ed., Molecular Beam Epitaxy Applications to Key Materials, Noyes Publications, Park Ridge, N.J., 1995. 

Thin semiconductor films (and other nanostructured materials) are widely used in many applications and, especially, in microelectronics. Current technological trends toward ultimate miniaturization of microelectronic devices require films as thin as less than 5 nm, that is, containing only several atomic layers [1]. Experimental deposition methods have been described in detail in recent reviews [2-7]. Common thin-film deposition techniques are subdivided into two main categories physical deposition and chemical deposition. Physical deposition techniques, such as evaporation, molecular beam epitaxy, or sputtering, involve no chemical surface reactions. In chemical deposition techniques, such as chemical vapor deposition (CVD) and its most important version, atomic layer deposition (ALD), chemical precursors are used to obtain chemical substances or their components deposited on the surface. 

S. K. Hong, Y. Chen, H. J. Ko, H. Wenisch, T. Hanada and T. Yao, ZnO and related materials Plasma-assisted molecular beam epitaxial growth, characterization, and application. J. Electron. Mater. 30 (2001) pp. 647-658. 

Recently, Mg and Be compounds have been used in alloys with ZnSe to make blue and green semiconductor lasers. Bulk growth by zone melting and molecular beam epitaxy (MBE) ° has been used. In these cases, good semiconductor material has been obtained dilution with group IIB compounds may be responsible. However, growth of pure MgS in very thin films on ZnSe has been achieved the epitaxial orientation effect of the substrate results in a tetrahedral cubic (sphalerite or zinc-blende) structure. It is likely that improvements in these materials will take place at a rapid rate, driven in part by applications and in part by newer, cleaner synthetic methods. 

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. 

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