Seed crystal

Seed crystal

A seed crystal is a small piece of single crystal material from which a large crystal of the same material typically is to be grown. The large crystal can be grown by dipping the seed into a supersaturated solution, into molten material that is then cooled, or by growth on the seed face by passing vapor of the material to be grown over it.

The theory behind this effect is thought to derive from the physical interaction that occurs intermolecularly between compounds in a supersaturated solution (or possibly vapor). In solution, liberated (soluble) molecules (solute) are free to move about in random flow. This random flow permits for the possibility of two or more molecular compounds to interact. This interaction can potentiate intermolecular forces between the separate molecules and form a basis for a crystal lattice. The placement of a seed crystal into solution allows the recrystallization process to expedite by eliminating the need for random molecular collision/interaction. By introducing an already pre-formed basis of the target crystal to act upon, the intermolecular interactions are formed much more easily/readily than relying on random flow. Often, this phase transition from solute in a solution to a crystal lattice will be referred to as nucleation. Seeding is therefore said to decrease the necessary amount of time needed for nucleation to occur in a recrystallization process.

One example where a seed crystal is used to grow large boules or ingots of a single crystal is the semiconductor industry where methods such as the Czochralski process or Bridgeman technique are employed.

See also

* Crystal
* Crystal growth
* Crystal structure
* [Crystallization]
* Recrystallization
* Single crystal

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См. также в других словарях:

  • seed crystal — kristalo užuomazga statusas T sritis fizika atitikmenys: angl. crystal nucleus; seed; seed crystal vok. Kristallisationskeim, m; Kristallkeim, m; Kristallkern, m rus. зародыш кристалла, m pranc. germe cristallin, m; germe de cristal, m; nacelle… …   Fizikos terminų žodynas

  • seed crystal — kristaliklis statusas T sritis chemija apibrėžtis Įterpta kristalizuojamos arba kitos medžiagos dalelė, kurios dydis didesnis už kritinį ir apie kurią gali išaugti kristalas. atitikmenys: angl. inoculating crystal; seed crystal rus. затравка;… …   Chemijos terminų aiškinamasis žodynas

  • seed crystal — užuomazginis kristalas statusas T sritis fizika atitikmenys: angl. inoculating crystal; seed crystal vok. Impfkristall, m; Kristallzuchtkeim, m rus. затравочный кристалл, m pranc. cristal germe, m …   Fizikos terminų žodynas

  • seed crystal — užuomazginis kristalas statusas T sritis radioelektronika atitikmenys: angl. seed crystal vok. Impfkristall, m; Keimkristall, m; Kristallkeim, m rus. затравочный кристалл, m pranc. cristal germe, m; germe cristallin, m ryšiai: palygink –… …   Radioelektronikos terminų žodynas

  • seed crystal — /ˈsid krɪstl/ (say seed kristl) noun 1. Chemistry a small crystal added to a saturated solution to initiate crystallisation. 2. one of a large number of crystals scattered into clouds to induce precipitation …   Australian English dictionary

  • Seed (disambiguation) — Seed, seeds or seeding may refer to: * Seed, an encased plant embryo * SEEDS, a non governmental organization * Sperm or semenBuddhism and Hinduism* Bija, literally seed , a metaphor for the origin or cause of thingsIn computing and technology*… …   Wikipedia

  • crystal — crystallike, adj. /kris tl/, n., adj., v., crystaled, crystaling or (esp. Brit.) crystalled, crystalling. n. 1. a clear, transparent mineral or glass resembling ice. 2. the transparent form of crystallized quartz. 3. Chem., Mineral. a solid body… …   Universalium

  • Crystal — /kris tl/, n. 1. a city in SE Minnesota, near Minneapolis. 25,543. 2. a female given name. * * * I Any solid material whose atoms are arranged in a definite pattern and whose surface regularity reflects its internal symmetry. Each of a crystal s… …   Universalium

  • Crystal oscillator — A miniature 4 MHz quartz crystal enclosed in a hermetically sealed HC 49/US package, used as the resonator in a crystal oscillator. A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal …   Wikipedia

  • Crystal growth — Crystallization Concepts …   Wikipedia

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