Atomic layer etching

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Atomic layer etching (ALE) is an emerging technique in semiconductor manufacture, in which a sequence alternating between self-limiting chemical modification steps which affect only the top atomic layers of the wafer, and etching steps which remove only the chemically-modified areas, allows the removal of individual atomic layers. The standard example is etching of silicon by alternating reaction with chlorine and etching with argon ions.

This is a better-controlled process than reactive ion etching, though the issue with commercial use of it has been throughput; sophisticated gas handling is required, and removal rates of one atomic layer per second are around the state of the art. [1]

The equivalent process for depositing material is atomic layer deposition (ALD). ALD is substantially more mature, having been used by Intel for high-κ dielectric layers since 2007 and in Finland in the fabrication of thin film electroluminescent devices since 1985. [2]

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<span class="mw-page-title-main">Semiconductor device fabrication</span> Manufacturing process used to create integrated circuits

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Glossary of microelectronics manufacturing terms

References

  1. "Atomic Layer Etch now in Fab Evaluations". 2014-08-04. Archived from the original on 2017-07-15. Retrieved 2015-05-29.
  2. Puurunen, Riikka L. (2014-12-01). "A Short History of Atomic Layer Deposition: Tuomo Suntola's Atomic Layer Epitaxy". Chemical Vapor Deposition. 20 (10–11–12): 332–344. doi: 10.1002/cvde.201402012 . ISSN   1521-3862.