Analytical Method for Calculating Curvature of Circular Silicon Wafer Caused by Boron Doping

Abstract:

Doping can lead to residual strain and change of elastic properties in silicon. Residual strain makes silicon wafer exhibit curvature, which are used for fabricate MEMS structure. The boron doping profile is not uniform through depth, which makes doped silicon become a inhomogeneous material or Functionally Graded Material. For boron-doped circular single crystal silicon wafer, a analytical method which based on functionally graded plate mechanics theory, is proposed to calculate its curvature. Example was used to verify the analytical method through 3D finite element simulation.

• Periodical: Key Engineering Materials (Volumes 562-565)
• Pages: 721-726
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.562-565.721
• Online since: July 2013
• Authors: Jiang Bo He, Jin Xie, Wu Zhou, Hao Qu, Peng Peng
• Keywords: Boron Doping, Curvature, Functionally Graded Plate, Residual Strain, Silicon Wafer

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