Patent · US Expired

System for laser removal of excess material from a semiconductor wafer

US4752668A · kind A · utility

51Cited by
8References
19Claims
0Family size

Inventors

Key dates

Filing dateApr 28, 1986
Grant dateJun 21, 1988
Priority date—
Expiry dateApr 28, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F1/72
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A system for removing excess material from a semiconductor wafer employs an excimer laser for ablative photocomposition. A wafer is positioned on an X-Y stage that is computer controlled to position the wafer at points where the laser may be focused to remove excess material whether over alignment marks or identified contamination. The laser passes through a vacuum chamber which by generating an inward laminar flow constrains any particulate contamination resulting from the ablative photodecomposition from spreading. This material is removed by the vacuum system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.