Lasertec releases new large mask blank inspection system LBIS


Major performance upgrade from previous model, contributing to yield improvement in high-resolution large photomask production

Lasertec Corporation announced the release of LBIS today. LBIS is an inspection system that delivers high sensitivity, high throughput inspection and defect review for large mask blanks used in the production of flat panel displays (FPDs).


The FPD industry today is facing challenges to meet the market demand for higher resolution displays used for high-definition smartphone displays and 4K and 8K TV sets. Patterns on large photomasks are shrinking fast, and yield critical defects on mask blank are getting smaller. Traditionally, mask blank manufacturers have employed visual inspection for quality assurance, but it is no longer a viable method for the large mask blank inspection. The industry now needs a highly reliable alternative that enables the high-sensitivity automated defect inspection and classification.

Lasertec has developed LBIS as a successor to LB79, released in 2008, to address the need for high-sensitivity mask blank inspection. LBIS incorporates a new optical design to achieve high sensitivity and high throughput. It also offers automated defect review and classification as a standard feature. LBIS is expected to play a key role in blank quality enhancement and mask yield improvement.

Key Features

  • New high-power laser light scattering optical system for high sensitivity and high throughput inspection
  • Reflected-light differential interference contrast (DIC) optics and transmitted-light optics for high magnification defect review
  • New software for automated defect review and classification
  • Up to G8/G10-size mask blanks supported
  • Compatible with various assist arms


  • Outgoing or incoming inspection and review of quartz substrates (after cleaning or polishing)
  • Defect inspection and review after chromium or chromium oxide deposition
  • Defect inspection and review after resist coating