Probing buried defects in extreme ultraviolet multilayer blanks using ultrasound holography

Gajendra S. Shekhawat, Shraddha Avasthy, Arvind K. Srivastava, Soo Hyun Tark, Vinayak P. Dravid

Research output: Contribution to journalArticlepeer-review

20 Scopus citations


Imaging high-resolution subsurface defects nondestructively in MoSi multilayer (ML) blanks used in extreme ultraviolet lithography is a challenge and no known metrology tools are available to identify such defects in a nondestructive way. The understanding of their growth mechanism during ML deposition necessitates the monitoring of these defects, which can then lead to fabricating defect-free ML blanks. Here, we report for the first time, a unique and novel application of scanning near-field ultrasound holography (SNFUH) in nondestructive imaging of high-resolution e-beam patterned lines and bumps buried under Mo/Si ML film stacks used for ultraviolet lithography. Our results indicate the successful identification of buried defects under ML blanks using SNFUH.

Original languageEnglish (US)
Article number5491187
Pages (from-to)671-674
Number of pages4
JournalIEEE Transactions on Nanotechnology
Issue number6
StatePublished - Nov 2010


  • Defect detection
  • metrology
  • near field
  • ultrasonics

ASJC Scopus subject areas

  • Computer Science Applications
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Probing buried defects in extreme ultraviolet multilayer blanks using ultrasound holography'. Together they form a unique fingerprint.

Cite this