Fabrication
Quantum wells are formed in semiconductors by having a material, like gallium arsenide sandwiched between two layers of a material with a wider bandgap, like aluminium arsenide. These structures can be grown by molecular beam epitaxy or chemical vapor deposition with control of the layer thickness down to monolayers.
(Other example: layer of indium gallium nitride (InGaN) sandwiched between two layers of gallium nitride (GaN). )
Thin metal films can also support quantum well states, in particular, metallic thin overlayers grown in metal and semiconductor surfaces. The electron (or hole) is confined by the vacuum-metal interface in one side, and in general, by an absolute gap with semiconductor substrates, or by a projected band gap with metal substrates.
Read more about this topic: Quantum Well
Famous quotes containing the word fabrication:
“What preoccupies us, then, is not God as a fact of nature, but as a fabrication useful for a God-fearing society. God himself becomes not a power but an image.”
—Daniel J. Boorstin (b. 1914)
“Some people are under the impression that all that is required to make a good fisherman is the ability to tell lies easily and without blushing; but this is a mistake. Mere bald fabrication is useless; the veriest tyro can manage that. It is in the circumstantial detail, the embellishing touches of probability, the general air of scrupulous—almost of pedantic—veracity, that the experienced angler is seen.”
—Jerome K. Jerome (1859–1927)
“Capitalism is an art form, an Apollonian fabrication to rival nature. It is hypocritical for feminists and intellectuals to enjoy the pleasures and conveniences of capitalism while sneering at it.... Everyone born into capitalism has incurred a debt to it. Give Caesar his due.”
—Camille Paglia (b. 1947)