RESEARCH ARTICLE

Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated circuit (IC) manufacturing process

  • Zilian QU ,
  • Yonggang MENG ,
  • Qian ZHAO
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  • State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China

Received date: 22 Dec 2014

Accepted date: 14 Jan 2015

Published date: 01 Apr 2015

Copyright

2015 Higher Education Press and Springer-Verlag Berlin Heidelberg

Abstract

This paper proposes a new eddy current method, named equivalent unit method (EUM), for the thickness measurement of the top copper film of multilayer interconnects in the chemical mechanical polishing (CMP) process, which is an important step in the integrated circuit (IC) manufacturing. The influence of the underneath circuit layers on the eddy current is modeled and treated as an equivalent film thickness. By subtracting this equivalent film component, the accuracy of the thickness measurement of the top copper layer with an eddy current sensor is improved and the absolute error is 3 nm for sampler measurement.

Cite this article

Zilian QU , Yonggang MENG , Qian ZHAO . Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated circuit (IC) manufacturing process[J]. Frontiers of Mechanical Engineering, 2015 , 10(1) : 1 -6 . DOI: 10.1007/s11465-015-0325-2

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