Separation of Superimposed Pulse-Echo Signal for Improvement of Resolution of Scanning Acoustic Microscope -Deconvolution Technique Combined with Wavelet Transform-

초음파 주사 현미경의 분해능 향상을 위한 중첩된 펄스에코 신호의 분리 기법(디컨볼루션과 웨이브렛 변환의 혼합기법)

  • 장경영 (한양대학교 기계공학부) ;
  • 장효성 (한양대학교 정밀기계공학) ;
  • 박병일 (한양대학교 정밀기계공학과)
  • Published : 2000.07.01

Abstract

Scanning Acoustic Microscope (SAM) is used as an important nondestructive test tool in semiconductor reliability evaluation and failure analysis. However, inspections of chip attach adhesive interface fer thin chip has proven difficulty as the reflected signals from the chip top and bottom are superimposed. In this paper, in order to overcome this difficulty, a new signal processing method based on the deconvolution technique combined with the wavelet transform is proposed. The wavelet transform complements a disability of deconvolution technique of which performance largely decreases when the waveform of target signal is not identical to that of reference signal. Performances of the proposed method are demonstrated by through computer simulations using model signal and experiments for the fabricated semiconductor samples, and satisfactory results are obtained.

Keywords

References

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