Czochralski method

Crystallization
Fundamentals
Concepts
Methods and technology

The Czochralski method, also Czochralski technique or Czochralski process, is a method of crystal growth used to obtain single crystals of semiconductors (e.g. silicon, germanium and gallium arsenide), metals (e.g. palladium, platinum, silver, gold), salts and synthetic gemstones. The method is named after Polish scientist Jan Czochralski,[1] who invented the method in 1915 while investigating the crystallization rates of metals.[2] He made this discovery by accident: instead of dipping his pen into his inkwell, he dipped it in molten tin, and drew a tin filament, which later proved to be a single crystal.[3] The method is still used in over 90 percent of all electronics in the world that use semiconductors.[4]

The most important application may be the growth of large cylindrical ingots, or boules, of single crystal silicon used in the electronics industry to make semiconductor devices like integrated circuits. Other semiconductors, such as gallium arsenide, can also be grown by this method, although lower defect densities in this case can be obtained using variants of the Bridgman–Stockbarger method.

The method is not limited to production of metal or metalloid crystals. For example, it is used to manufacture very high-purity crystals of salts, including material with controlled isotopic composition, for use in particle physics experiments, with tight controls (part per billion measurements) on confounding metal ions and water absorbed during manufacture.[5]

  1. ^ Paweł Tomaszewski, "Jan Czochralski i jego metoda. Jan Czochralski and his method" (in Polish and English), Oficyna Wydawnicza ATUT, Wrocław–Kcynia 2003, ISBN 83-89247-27-5
  2. ^ J. Czochralski (1918). "Ein neues Verfahren zur Messung der Kristallisationsgeschwindigkeit der Metalle [A new method for the measurement of the crystallization rate of metals]". Zeitschrift für Physikalische Chemie. 92: 219–221. doi:10.1515/zpch-1918-9212.
  3. ^ Nishinaga, Tatau (2015). Handbook of Crystal Growth: Fundamentals (Second ed.). Amsterdam, the Netherlands: Elsevier B.V. p. 21. ISBN 978-0-444-56369-9.
  4. ^ Stuart Dowell. "Scientist who laid the foundations for Silicon Valley honoured at long last". thefirstnews.com. Archived from the original on 13 July 2023. Retrieved 3 May 2023.
  5. ^ Son, JK (2020-05-14). "Growth and development of pure Li2MoO4 crystals for rare event experiment at CUP". Journal of Instrumentation. 15 (7): C07035. arXiv:2005.06797. Bibcode:2020JInst..15C7035S. doi:10.1088/1748-0221/15/07/C07035. S2CID 218630318.