DOI QR코드

DOI QR Code

Theoretical Analysis of Secondary Current Distributions for Electrode with a Projection Part in Electroplating System

돌출부를 지닌 전극의 전기도금시스템에 대한 이론적 이차 전류분포 해석

  • Sohn, Tai-Won (Department of Chemical Engineering, Hong Ik University) ;
  • Ju, Jeh-Beck (Department of Chemical Engineering, Hong Ik University)
  • 손태원 (홍익대학교 공과대학 화학공학과) ;
  • 주재백 (홍익대학교 공과대학 화학공학과)
  • Published : 2009.11.30

Abstract

Theoretical calculations for the secondary current distributions for the electrode with a projection part in electroplating were performed. Two kinds of electrodes were considered. One is a electrode with the overall conducting surfaces(Case 1) and the other is an electrode in which only a projection part has a conducting surface(Case 2). The effects of applied potential, the ratio of ion exchange current to conductivity, $\xi$ and the aspect ratio on the current distribution were examined. The increase of applied current or the value of $\xi$ decreased the uniformity of current distribution. The small value of aspect ratio resulted the more uniform current distribution and Case 2 showed the better uniformity than Case 2. When this model was applied into an electrode with various projection parts, the local current distribution along the electrode surface were obtained successfully. In this case, the decrease of $\xi$ also increase the uniformity of current distribution as seen previously.

돌출부를 지니고 있는 전극의 전기도금 공정에 대한 이론적 이차 전류분포에 대하여 고찰하였다. 전극이 모두 전도체인 경우(Case 1)와 돌출부위만 전도체인 경우(Case 2) 두 가지 경우에 대하여 인가전위, 이온교환 전류밀도와 용액의 비전도도의 비인 $\xi$값, aspect ratio의 영향 등에 대하여 살펴보았다. 그 결과 인가 전위와 $\xi$값이 증가할수록 전류분포는 불균등화가 심화됨을 알 수 있었다. Aspect ratio가 작아질수록 전류분포가 보다 균등화되며 Case 2의 경우가 Case 1의 경우 보다 균등도가 좋아짐을 알 수 있었다. 돌출부위가 다양한 모양으로 이루진 전극에 대해서도 이 모델을 적용한 결과 전극 표면에 따른 국부 전류분포를 동시에 계산할 수 있음을 알 수 있었고 이 경우에도 이전과 마찬가지로 $\xi$값이 감소할수록 전류분포의 균등도가 좋아짐을 알 수 있었다.

Keywords

References

  1. M. Datta, 'Microfabrication by Electrochemical Metal Removal' IBM J. Res. & Devel,, 42, 655 (1988) https://doi.org/10.1147/rd.425.0655
  2. D. Landolt, 'Electrodeposition Sciences and Technology in the Last Quater of the Twenties Century', J. Electrochemical Society, 149, S9 (2002) https://doi.org/10.1149/1.1469028
  3. M. Narashimhan, 'Inline Process Control of Advanced Thin Films' www.kla-tencor.com/magazine, 1 (2004)
  4. R. Moutton, "Three-dimensional PCB Electroplating Simulation Tools", Presented at IPC Printed Circuits EXPO, www. ipcprintedcircuitsexpo.org, S10-2-1 (2001)
  5. T. Park, T. Tugbawa, and D. Boning, 'Pattern Dependent Modeling of Electroplated Copper Profiles' International Interconnect Technology Conference(IITC), 274, San Francisco, CA, June (2001)
  6. T. Park, Ph. D. Thesis, "Characterization and Modeling of Pattern Dependencies in Copper Interconnects for Integrated Circuits", MIT, June (2002)
  7. G. A. Prentice and C. W. Tobias, 'A Survey of Numerical Methods and Solutions for Current Distribution Problems' J. Electrochemical Society. 129, 72 (1982) https://doi.org/10.1149/1.2123795
  8. J. Newman," Electrochemical Systems", John & Wileys, New York (1991)
  9. C. T. J. Low, E. P. L. Roberts and F. C. Walsh, 'Numerical Simulation of the Current, Potential and Concentration Distributions along the Cathode of Rotating Cylinder Hull Cell', Electrochimica Acta , 52, 3831 (2007) https://doi.org/10.1016/j.electacta.2006.10.056
  10. I. O. Dukovic, 'Computation of Current Distribution in Electrodeposition, a Review' IBM J. Res. & Devel,, 34, 693 (1990) https://doi.org/10.1147/rd.345.0693
  11. J. Deconinck, "Current Distributions and Electrode Shape Changes in Electrochemical Systems", Springer-Verlag, London (1992)
  12. J. Lee and J.B. Talbot, "Simulation of Electrochemical Processes" WIT Transactions on Eng. Sci., 48, WIT Press, Boston (2005)
  13. FlexPde Professional, www.PdeSolutions.com