DOI QR코드

DOI QR Code

Investigation and Analysis of Cracks in Multi-layer Ceramic Capacitor

다층세라믹 콘덴서에서 생성된 크랙의 관찰과 분석

  • Published : 2009.03.31

Abstract

For the Y5V characteristic MLCC which is very prone to crack, it is important to to find out the basic cause of the crack. After finding out the crack origin, the materials and processes should be developed to remove the crack. The microstructures of the cracks were investigated using the fractographic method for the various types of cracks such as an exterior crack, a cyclic thermal shock crack, and an piezo-electric crack. It was found out that the crack origin was the pore at the end of the Ni inner electrode after bake-out. Even though the three dimensional crack shapes were different, the crack origins were seemed to be similar. The exterior crack could grow from the origin with the aids of residual and applied stress. FEM (finite element method) analysis was used to calculate the stress distribution of residual and applied stress. And the concept of fracture mechanics was applied for the explanation of the crack initiation and propagation from the stresses concentration.

Keywords

References

  1. F. Guiberteau, N. P. Padture, and B. R. Lawn, “Effect of Grain Size on Hertzian Contact in Alumina,” J. Am. Ceram. Soc., 77 [7] 1825-31 (1994). https://doi.org/10.1111/j.1151-2916.1994.tb07057.x
  2. B. R. Lawn and T. R. Wilshaw, “Indentation Fracture: Principles and Applications,” J. Mater. Sci., 10 [6] 1049-81 (1975). https://doi.org/10.1007/BF00823224
  3. B. R. Lawn, Fracture of Brittle Solids, 2nd Ed., Chp 2, pp.16-50, and chp8, pp.249-306, Cambridge University Press, Cambridge, 1993.
  4. L. M. Braun, S. J.p Bennison, and B. R. Lawn, “Objective Evaluation of Short-Crack Toughness-Curves Using Indentation Flaws: Case Study on Alumina-Based Ceramics,” J. Am. Ceram. Soc., 75 [11] 3049-57 (1992). https://doi.org/10.1111/j.1151-2916.1992.tb04385.x
  5. B. R. Lawn, E. R. Fuller, and S. M. Wiederhorn, “Strength Degradation of Brittle Surfaces: Sharp Indenters,” J. Am. Ceram. Soc., 59 [5-6] 193-97 (1976). https://doi.org/10.1111/j.1151-2916.1976.tb10930.x
  6. G. R. Anstis, P. Chantikul, D. B. Marshall, and B. R. Lawn, “A Critical Evaluation of Indentation Techniques for Measuring Fracture Toughness: I. Direct Crack Measurements,” J. Am. Ceram. Soc., 64 [9] 533-38 (1981). https://doi.org/10.1111/j.1151-2916.1981.tb10320.x

Cited by

  1. Design and Analysis of Electrical Properties of a Multilayer Ceramic Capacitor Module for DC-Link of Hybrid Electric Vehicles vol.8, pp.4, 2013, https://doi.org/10.5370/JEET.2013.8.4.808