At the National Institute of Standards and Technology (NIST), we are developing two interferometric methods for measuring the thickness variation and flatness of free-standing and chucked silicon wafers with diameters up to 300mm. The eXtremely accurate CALIBration InterferometeR (XCALIBIR) is a precision phase measuring interferometer with an operating vacelength of 633nm and a test beam of 300 mm diameter. XCALIBIR is used to evaluate the flatness of chucked wafers. NIST''s infrared interferometer (IR2) is a phase measuring interferometer that operates at 1.55um and is used to measure the thickness variation of free-standing 300 mm silicon wafers.
Proceedings Title: American Institute of Physics Proceedings of the 2005 Conference on Characterization and Metrology for ULSI Technology
Conference Dates: March 15-28, 2005
Conference Location: Dallas, TX
Conference Title: American Institute of Physics Conference on Characterization and Metrology for ULSI Technology
Pub Type: Conferences
300mm silicon wafers, wafer flatness, wafer thickness variation (TTV and GBIR)