Atomic-scale silicon etching control using pulsed Cl-2 plasma

作者:Petit Etienne Camille*; Darnon Maxime; Bodart Paul; Fouchier Marc; Cunge Gilles; Pargon Erwine; Vallier Laurent; Joubert Olivier; Banna Samer
来源:JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B, 2013, 31(1): 011201.
DOI:10.1116/1.4768717

摘要

Plasma etching has been a key driver of miniaturization technologies toward smaller and more powerful devices in the semiconductor industry. Thin layers involved in complex stacks of materials are approaching the atomic level. Furthermore, new categories of devices have complex architectures, leading to new challenges in terms of plasma etching. New plasma processes that are capable to etch ultra-thin layers of materials with control at the atomic level are now required. In this paper, the authors demonstrate that Si etching in Cl-2 plasma using plasma pulsing is a promising way to decrease the plasma-induced damage of materials. A controlled etch rate of 0.2 nm min(-1) is reported by pulsing the chlorine plasma at very low duty cycles. Using quasi-in-situ angle resolved XPS analyses, they show that the surface of crystalline silicon is less chlorinated, the amorphization of the top crystalline silicon surface is decreased, and the chamber wall are less sputtered in pulsed plasmas compared to continuous wave plasmas. This is attributed to the lower density of radicals, lower ion flux, and lower V-UV flux when the plasma is pulsed.

  • 出版日期2013-1
  • 单位中国地震局