Patent · US Active

Silicon filter for photoluminescence metrology

US8330946B2 · kind B2 · utility

3Cited by
3References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 15, 2009
Grant dateDec 11, 2012
Priority date—
Expiry dateJan 12, 2031

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/9501
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus identifies defects in a sample using photoluminescence with a silicon filter to filter out the primary excitation light from the return light received by the detector. The silicon filter passes the light emitted by the sample in response to the excitation light, while absorbing the lower wavelength excitation light that is reflected by or transmitted through the sample. The silicon filter has introduced impurities that reduce the recombination lifetime which reduces or eliminate photoluminescence in the silicon filter in response to the excitation light, thereby improving the signal to noise ratio of the signal received by the detector.

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