A predictive divergence compensation approach for the fabrication of three-dimensional microstructures using focused ion beam machining

J. Sun, Xichun Luo, J. Ritchie, T. Hrncir

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

In this paper, the major factors which cause fabrication divergence in the focused ion beam (FIB) milling process are discussed. A divergence compensation approach is outlined which calculates the corrected dwell time in order to allow for the divergence caused by the FIB milling process; this is due to overlap effects and the angular-dependent sputter yield. A multi-pass scanning method is used to reduce the fabrication divergence precipitated by atom redeposition. Microstructures, such as parabolic, hemispherical and sinusoidal shapes and a nano hemispherical structure have been produced during the FIB milling experiments using conventional bitmap milling and proposed divergence compensation approaches. A flat top/bottom surface is obtained in convex/concave structures when using the conventional bitmap FIB milling approach. Further research shows that the reasons for this phenomenon are mainly related to both the aspect ratio of the structures and the existence of an oxide layer on the substrate surface. The flat top/bottom phenomenon can be removed by using the combination of a novel divergence compensation approach and the removal of the oxide layer from the substrate surface prior to FIB machining. The experimental results show that the surface form accuracy has been greatly improved by using this method and the overlap effect can be suppressed by carefully choosing the normalized pixel spacing.
LanguageEnglish
Pages229-238
Number of pages10
JournalProceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture
Volume226
Issue number2
Early online date12 Nov 2011
DOIs
Publication statusPublished - Feb 2012

Fingerprint

Focused ion beams
Machining
Fabrication
Microstructure
Oxides
Substrates
Aspect ratio
Pixels
Compensation and Redress
Scanning
Atoms
Experiments

Keywords

  • focused ion beam (FIB)
  • micro fabrication
  • bitmap
  • divergence compensation
  • error correction

Cite this

@article{001f8b1c6ad44a8ba29b9380e61eee60,
title = "A predictive divergence compensation approach for the fabrication of three-dimensional microstructures using focused ion beam machining",
abstract = "In this paper, the major factors which cause fabrication divergence in the focused ion beam (FIB) milling process are discussed. A divergence compensation approach is outlined which calculates the corrected dwell time in order to allow for the divergence caused by the FIB milling process; this is due to overlap effects and the angular-dependent sputter yield. A multi-pass scanning method is used to reduce the fabrication divergence precipitated by atom redeposition. Microstructures, such as parabolic, hemispherical and sinusoidal shapes and a nano hemispherical structure have been produced during the FIB milling experiments using conventional bitmap milling and proposed divergence compensation approaches. A flat top/bottom surface is obtained in convex/concave structures when using the conventional bitmap FIB milling approach. Further research shows that the reasons for this phenomenon are mainly related to both the aspect ratio of the structures and the existence of an oxide layer on the substrate surface. The flat top/bottom phenomenon can be removed by using the combination of a novel divergence compensation approach and the removal of the oxide layer from the substrate surface prior to FIB machining. The experimental results show that the surface form accuracy has been greatly improved by using this method and the overlap effect can be suppressed by carefully choosing the normalized pixel spacing.",
keywords = "focused ion beam (FIB) , micro fabrication, bitmap, divergence compensation, error correction",
author = "J. Sun and Xichun Luo and J. Ritchie and T. Hrncir",
year = "2012",
month = "2",
doi = "10.1177/0954405411408185",
language = "English",
volume = "226",
pages = "229--238",
journal = "Proceedings for Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture",
issn = "0954-4054",
number = "2",

}

TY - JOUR

T1 - A predictive divergence compensation approach for the fabrication of three-dimensional microstructures using focused ion beam machining

AU - Sun, J.

AU - Luo, Xichun

AU - Ritchie, J.

AU - Hrncir, T.

PY - 2012/2

Y1 - 2012/2

N2 - In this paper, the major factors which cause fabrication divergence in the focused ion beam (FIB) milling process are discussed. A divergence compensation approach is outlined which calculates the corrected dwell time in order to allow for the divergence caused by the FIB milling process; this is due to overlap effects and the angular-dependent sputter yield. A multi-pass scanning method is used to reduce the fabrication divergence precipitated by atom redeposition. Microstructures, such as parabolic, hemispherical and sinusoidal shapes and a nano hemispherical structure have been produced during the FIB milling experiments using conventional bitmap milling and proposed divergence compensation approaches. A flat top/bottom surface is obtained in convex/concave structures when using the conventional bitmap FIB milling approach. Further research shows that the reasons for this phenomenon are mainly related to both the aspect ratio of the structures and the existence of an oxide layer on the substrate surface. The flat top/bottom phenomenon can be removed by using the combination of a novel divergence compensation approach and the removal of the oxide layer from the substrate surface prior to FIB machining. The experimental results show that the surface form accuracy has been greatly improved by using this method and the overlap effect can be suppressed by carefully choosing the normalized pixel spacing.

AB - In this paper, the major factors which cause fabrication divergence in the focused ion beam (FIB) milling process are discussed. A divergence compensation approach is outlined which calculates the corrected dwell time in order to allow for the divergence caused by the FIB milling process; this is due to overlap effects and the angular-dependent sputter yield. A multi-pass scanning method is used to reduce the fabrication divergence precipitated by atom redeposition. Microstructures, such as parabolic, hemispherical and sinusoidal shapes and a nano hemispherical structure have been produced during the FIB milling experiments using conventional bitmap milling and proposed divergence compensation approaches. A flat top/bottom surface is obtained in convex/concave structures when using the conventional bitmap FIB milling approach. Further research shows that the reasons for this phenomenon are mainly related to both the aspect ratio of the structures and the existence of an oxide layer on the substrate surface. The flat top/bottom phenomenon can be removed by using the combination of a novel divergence compensation approach and the removal of the oxide layer from the substrate surface prior to FIB machining. The experimental results show that the surface form accuracy has been greatly improved by using this method and the overlap effect can be suppressed by carefully choosing the normalized pixel spacing.

KW - focused ion beam (FIB)

KW - micro fabrication

KW - bitmap

KW - divergence compensation

KW - error correction

U2 - 10.1177/0954405411408185

DO - 10.1177/0954405411408185

M3 - Article

VL - 226

SP - 229

EP - 238

JO - Proceedings for Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture

T2 - Proceedings for Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture

JF - Proceedings for Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture

SN - 0954-4054

IS - 2

ER -