Schottky defect

Schottky defect

A Schottky defect is a type of point defect in a crystal lattice named for Walter H. Schottky. The defect forms when oppositely charged ions leave their lattice sites, creating vacancies. These vacancies are formed in stoichiometric units, to maintain an overall neutral charge in the ionic solid. The vacancies are then free to move about as their own entities. Each vacancy is a separate Schottky defect.Normally these defects will lead to a decrease in the density of the crystal.The following are the chemical equations in Kröger-Vink Notation for the formation of Schottky defects in TiO_2 and BaTiO_3.

Ø Leftrightarrow V_{Ti}"" + 2V_O^{ullet ullet}

Ø Leftrightarrow V_{Ba}" + V_{Ti}"" + 3V_O^{ullet ullet}

This can be illustrated schematically with a two-dimensional diagram of a sodium chloride crystal lattice:


ee also

*Frenkel defect
*Crystallographic defects

References

External links


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • schottky defect — ˈshätkē noun Usage: usually capitalized S Etymology: after Walter Schottky b1886 German physicist : a defect in a crystal lattice created by removing an ion from its normal site and placing it on the crystal surface * * * /shot kee/, Crystall. an …   Useful english dictionary

  • Schottky defect — Šotkio defektas statusas T sritis fizika atitikmenys: angl. Schottky defect vok. Schottky Defekt, m rus. дефект Шотки, m; дефект Шоттки, m pranc. défaut de Schottky, m …   Fizikos terminų žodynas

  • Schottky defect — /shot kee/, Crystall. an unoccupied position in a crystal lattice caused by the relocation of an atom or ion from the interior to the surface of the crystal. [named after Walter Hans Schottky (1886 1976), German physicist, who described it] * * * …   Universalium

  • Schottky — Notable people named Schottky include:* Ernst Max Schottky, botanist * Walter H. Schottky, physicist * Friedrich Schottky, mathematicianOther links:* Schottky diode and Schottky barrier in electronics and physics * Schottky group in mathematics * …   Wikipedia

  • Schottky, Walter — ▪ German physicist born July 23, 1886, Zürich, Switz. died March 4, 1976, Pretzfeld, W.Ger.       German physicist whose research in solid state physics and electronics yielded many devices that now bear his name.       Schottky obtained… …   Universalium

  • Schottky anomaly — noun A variation in the heat capacity of a solid at low temperatures which arises from the thermal population of discrete energy levels as the temperature is raised See Also: Schottky barrier, Schottky defect, Schottky diode, Schottky effect,… …   Wiktionary

  • Schottky-Defekt — Šotkio defektas statusas T sritis fizika atitikmenys: angl. Schottky defect vok. Schottky Defekt, m rus. дефект Шотки, m; дефект Шоттки, m pranc. défaut de Schottky, m …   Fizikos terminų žodynas

  • schottky effect — n. Electronics the increase in thermionic emission from a solid surface due to the presence of an external electric field. Etymology: W. Schottky, Ger. physicist d. 1976 * * * noun Usage: usually capitalized S : the increase of the thermionic… …   Useful english dictionary

  • Schottky noise — Electronics. See shot effect. [see SCHOTTKY DEFECT] * * * …   Universalium

  • schottky barrier — noun Usage: usually capitalized S Etymology: Schottky defect : a potential barrier that exists at a metal semiconductor interface (as in a solid state electronic device) …   Useful english dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”