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Title: Alternative process for thin layer etching: Application to nitride spacer etching stopping on silicon germanium

Abstract

Silicon nitride spacer etching realization is considered today as one of the most challenging of the etch process for the new devices realization. For this step, the atomic etch precision to stop on silicon or silicon germanium with a perfect anisotropy (no foot formation) is required. The situation is that none of the current plasma technologies can meet all these requirements. To overcome these issues and meet the highly complex requirements imposed by device fabrication processes, we recently proposed an alternative etching process to the current plasma etch chemistries. This process is based on thin film modification by light ions implantation followed by a selective removal of the modified layer with respect to the non-modified material. In this Letter, we demonstrate the benefit of this alternative etch method in term of film damage control (silicon germanium recess obtained is less than 6 A), anisotropy (no foot formation), and its compatibility with other integration steps like epitaxial. The etch mechanisms of this approach are also addressed.

Authors:
; ;  [1]
  1. CEA-LETI-Minatec, 17 rue des martyrs, 38054 Grenoble cedex 09 (France)
Publication Date:
OSTI Identifier:
22314477
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ETCHING; FABRICATION; GERMANIUM; PLASMA; SILICON; SILICON NITRIDES; THIN FILMS

Citation Formats

Posseme, N., E-mail: nicolas.posseme@cea.fr, Pollet, O., and Barnola, S. Alternative process for thin layer etching: Application to nitride spacer etching stopping on silicon germanium. United States: N. p., 2014. Web. doi:10.1063/1.4892543.
Posseme, N., E-mail: nicolas.posseme@cea.fr, Pollet, O., & Barnola, S. Alternative process for thin layer etching: Application to nitride spacer etching stopping on silicon germanium. United States. doi:10.1063/1.4892543.
Posseme, N., E-mail: nicolas.posseme@cea.fr, Pollet, O., and Barnola, S. Mon . "Alternative process for thin layer etching: Application to nitride spacer etching stopping on silicon germanium". United States. doi:10.1063/1.4892543.
@article{osti_22314477,
title = {Alternative process for thin layer etching: Application to nitride spacer etching stopping on silicon germanium},
author = {Posseme, N., E-mail: nicolas.posseme@cea.fr and Pollet, O. and Barnola, S.},
abstractNote = {Silicon nitride spacer etching realization is considered today as one of the most challenging of the etch process for the new devices realization. For this step, the atomic etch precision to stop on silicon or silicon germanium with a perfect anisotropy (no foot formation) is required. The situation is that none of the current plasma technologies can meet all these requirements. To overcome these issues and meet the highly complex requirements imposed by device fabrication processes, we recently proposed an alternative etching process to the current plasma etch chemistries. This process is based on thin film modification by light ions implantation followed by a selective removal of the modified layer with respect to the non-modified material. In this Letter, we demonstrate the benefit of this alternative etch method in term of film damage control (silicon germanium recess obtained is less than 6 A), anisotropy (no foot formation), and its compatibility with other integration steps like epitaxial. The etch mechanisms of this approach are also addressed.},
doi = {10.1063/1.4892543},
journal = {Applied Physics Letters},
number = 5,
volume = 105,
place = {United States},
year = {Mon Aug 04 00:00:00 EDT 2014},
month = {Mon Aug 04 00:00:00 EDT 2014}
}
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