Microsystem Technologies

, Volume 14, Issue 9–11, pp 1223–1226 | Cite as

Fabricating HARMS by using megasonic assisted electroforming

  • Gang LiuEmail author
  • Xinlong Huang
  • Ying Xiong
  • Yangchao Tian
Technical Paper


Electroforming is a main fabrication method to produce metal microstructures for microelectromechanical systems. Since the mass transport is limited in high aspect ratio microstructures (HARMS), problems such as uneven filling and void formation are often involved in the electroplating of deep molds. In this work, megasonic agitation is employed to improve the electroplating of HARMS, which causes little damage to the resist structure and is thereby advantageous over ultrasonic agitation. Cantilever beams and gaps with a linewidth of 10 μm and an aspect ratio of 25 have been obtained. The main effects of megasonic agitation are analyzed. The results indicate that resonant bubbles in the electrolyte are probably responsible for the mass transport enhancement during the electroforming process.


Cavitation Cantilever Beam Peclet Number Acoustic Streaming Viscous Boundary Layer 
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  1. Chen KS, Evans GH (2004) Two-dimensional modeling of nickel electrodeposition in LIGA microfabrication. Microsyst Technol 10(6/7):444–450CrossRefGoogle Scholar
  2. Deymier PA, Vasseur JO, Khelif A et al (2001) Second-order sound field during megasonic cleaning of patterned silicon wafers: application to ridges and trenches. J Appl Phys 90(8):4211–4218CrossRefGoogle Scholar
  3. Griffiths SK, Nilson RH, Bradshaw RW et al (1998) Transport limitations in electrodeposition for LIGA microdevice fabrication. Proc SPIE 3511:364–375CrossRefGoogle Scholar
  4. Hyde ME, Compton RG (2002) How ultrasound influences the electrodeposition of metals. J Electroanal Chem 531:19–24CrossRefGoogle Scholar
  5. Kupka RK, Bouamrane F, Cremers C et al (2000) Microfabrication: LIGA-X and applications. Appl Surf Sci 164:97–110CrossRefGoogle Scholar
  6. Kuttruff H (1991) Ultrasonics, fundamentals and applications. Elsevier, New YorkzbMATHGoogle Scholar
  7. Nilson RH, Griffiths SK (2002) Enhanced transport by acoustic streaming in deep trench-like cavities. J Electrochem Soc 149(4):G286–G296CrossRefGoogle Scholar
  8. Zanghellini J, Achenback S, El-Kholi A et al (1998) New development strategies for high aspect ratio microstructures. Microsyst Technol 4:94–97CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Gang Liu
    • 1
    Email author
  • Xinlong Huang
    • 1
  • Ying Xiong
    • 1
  • Yangchao Tian
    • 1
  1. 1.National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefeiPeople’s Republic of China

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