Laser recovery of subsurface damages in chemomechanically polished silicon wafers

Keiichiro Niitsu, Yu Tayama, Hidenobu Maehara, Taketoshi Kato, Jiwang Yan

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Silicon wafers are the most widely used semiconductor substrates. It has been considered that silicon wafers after chemomechanical polishing (CMP) have no subsurface defects. However, in fact, defects such as dislocation and latent microcracks will remain in the wafers if CMP is performed under unsuitable conditions. In this study, we confirmed the existence of subsurface damages at a depth of submicron level in a silicon wafer after CMP, then used a nanosecond pulsed Nd:YAG laser to repair the subsurface damages. It was found that subsurface defects were recovered to a single crystalline structure by laser irradiation without changing the surface topography. The phase transformation of silicon before and after laser irradiation was confirmed by laser Raman spectroscopy and chemical etching using saturated aqueous solution of Ca(OH)2. The findings from this study contributes to improve the quality of silicon wafers for high-performance semiconductors.

Original languageEnglish
Title of host publicationScience and Engineering of Materials II
Subtitle of host publicationMaterials and Technology for a Sustainable Future
EditorsChin-Che Tin, Chin-Che Tin, Mohd. Rafie Johan
PublisherTrans Tech Publications Ltd
Pages97-100
Number of pages4
ISBN (Print)9783038356875
DOIs
Publication statusPublished - 2016 Jan 1
Event2nd International Conference on Science and Engineering of Materials, ICoSEM 2015 - Kuala Lumpur, Malaysia
Duration: 2015 Nov 162015 Nov 18

Publication series

NameKey Engineering Materials
Volume701
ISSN (Print)1013-9826
ISSN (Electronic)1662-9795

Other

Other2nd International Conference on Science and Engineering of Materials, ICoSEM 2015
CountryMalaysia
CityKuala Lumpur
Period15/11/1615/11/18

Keywords

  • Chemical etching
  • Laser recovery
  • Polished wafer
  • Single crystalline silicon
  • Subsurface damage

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

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  • Cite this

    Niitsu, K., Tayama, Y., Maehara, H., Kato, T., & Yan, J. (2016). Laser recovery of subsurface damages in chemomechanically polished silicon wafers. In C-C. Tin, C-C. Tin, & M. R. Johan (Eds.), Science and Engineering of Materials II: Materials and Technology for a Sustainable Future (pp. 97-100). (Key Engineering Materials; Vol. 701). Trans Tech Publications Ltd. https://doi.org/10.4028/www.scientific.net/KEM.701.97