The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 24, 2005
Filed:
Dec. 21, 2001
Steven W. Meeks, Fremont, CA (US);
Steven W. Meeks, Fremont, CA (US);
Candela Instruments, Fremont, CA (US);
Abstract
A system and method for measuring defects, film thickness, contamination, particles and height of a thin film disk or a silicon wafer. The system includes a processor for determining height. In addition to measuring the height the system can measure film thickness and defects through the measurement of the phase shift of optical signals. An optical profilometer is described which can measure topography on thin film disks, optical substrates or silicon wafers and whose output is independent of the reflectivity of the substrate. This material independent optical profilometer uses a retro-reflector to achieve reflectivity independence and to increase the height sensitivity to 8 times the height of the surface. The reflectivity independent optical profilometer achieves perfect cancellation of the slope of the surface while measuring the topography of the substrate.