Epitaxial structures

Epitaxial structures

Epitaxial interfaces in solids are a special class of crystalline interfaces where the molecular arrangement of one crystal on top of another is defined by the crystallographic and chemical features of the underlying crystal. The term “epitaxy” was introduced to describe the importance of having parallelism between two lattice planes with similar networks of closely similar spacing. Epitaxial phenomena are important to study and understand, as they occur widely in nature (such as oxidation) and are the foundation by which modern semiconductor devices are grown and fabricated.

Epitaxial interfaces are a subset of a class of interfaces where lattice planes achieve a correspondence across an interface. If the matching is not perfect, such a correspondence can be achieved by a number of ways, including dilation and contraction of lattice planes; rotation of overgrowth (epilayer relative to the orientation of the substrate) until a set of closely matched lattice spacing can be found; and tilting of the epilayer with respect to the substrate (see illustration).

The extent to which epitaxial films are mechanically stable due to coherency stresses is governed not only by the extent of lattice misfit but also by the strength of the chemical bond between the epilayer and the substrate. This property of adhesion is manifested by the extent to which the overlayer wets the substrate. Extremely thin layers that are only a few atoms thick can be produced. Such thin layers form the microstructural foundation for the fabrication of quantum wells, which are extremely important in semiconductor device applications. See Quantized electronic structure (QUEST)

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He also serves as Chairman of Firmus SAM, a Monaco-based nanotechnology company active in the production of graphene and other epitaxial structures and as Executive Chairman of Hudson Oil, a Canadian downstream energy firm active in Poland.
The researchers agree that their new findings were made possible by their crystal-metal hybrid nanostructures, which offer a number of benefits over the epitaxial structures used for previous work.
While suppliers have traditionally focused on providing HBT (Heterojunction Bipolar Transistor), HEMT (High Electron Mobility Transistor) and FET (Field Effect Transistor) epitaxial structures, the market is seeing greater emphasis on solutions that allow multiple structures to be combined on the one substrate in order to provide BiFET (Bipolar Field Effect Transistor) or BiHEMT (Bipolar High Electron Mobility Transistor) devices.
This partnership with Soitec to commercialize sSOI further extends ASM's leadership in supplying single-wafer epitaxial tools with unique production solutions for precisely controlled epitaxial structures.
The key to this success was the optimization of the epitaxial structures, particularly with regard to reducing electrical losses to a minimum.
Most recently, Dr Kordina was Senior Scientist at Linko-ping University in Sweden where he developed epitaxial structures for radio frequency and power devices.
Our extensive MOCVD experience and capabilities enable us to grow a wide variety of GaAs and InP epitaxial structures," said Edward D.
The Company is a pioneer in the growth and processing of nano-scaled semiconductor-based materials, such as quantum cascade epitaxial structures, which enable the fabrication of many advanced optoelectronic devices including terahertz lasers and detectors.
The company's activities encompass manufacturing of III-V epitaxial wafers, development of new MOCVD technologies and the design and production of semiconductor devices based on MOCVD epitaxial structures.
Vektor-DCD uses classic double-crystal x-ray optics for the best possible combination of resolution and intensity when measuring epitaxial structures with low dislocation densities such as GaAs and InP based lasers, p-HEMTs and HBTs.
IQE's Silicon Compounds division is Europe's first fully flexible, dedicated outsource service for silicon based epitaxial structures, and is an ideal partner for us because it takes our intellectual property position and moves it into global high-volume production," said Mark Wolf, President and CEO of AmberWave Systems.