Patent Number: 6,486,946

Title: Method for discriminating between holes in and particles on a film covering a substrate

Abstract: P-polarized light or having a strong P-polarized component is directed onto a filmed substrate at two (or more) different incidence angles, one angle being relatively large and the other angle being relatively small as measured from a surface normal. Light that is scattered into a back region of the hemispherical space above the substrate surface is collected and the intensity of the collected light is measured for each of the two incident angles. A defect can be classified as either a hole in the film or a particle on the film based on the relative intensities of the collected light.

Inventors: Stover; John C. (Charlotte, NC), Eremin; Yuri A. (Moscow, RU)

Assignee: ADE Corporation

International Classification: G01N 21/88 (20060101); G01N 21/94 (20060101); G01N 21/95 (20060101); G01N 21/84 (20060101); G01N 021/00 (); G01N 021/83 ()

Expiration Date: 11/26/2019