Haidinger Interferometer for Silicon Wafer TTV Measurement
R E. Parks, L Z. Shao, Angela Davies, Christopher J. Evans
We describe a novel configuration for a Haidinger fringe, phase shifting, interferometer to measure the total thickness variation (TTV) of 300mm silicon wafers. The interferometer has only one optical element that is on the order of the size of the wafer under test, a concave spherical mirror of moderate quality. Further, the interferometer has no moving parts, the phase shifting being done by changing the wavelength of a tunable 1.55 micrometer diode laser. Because of the modest size and quality of the optics, and no moving parts, the interferometer is robust, compact and relatively inexpensive given the 300mm aperature.
Characterization and Metrology for ULSI Technology Conference
Interferometry, Metrology, Total Thickness Variation, Wafer TTV
, Shao, L.
, Davies, A.
and Evans, C.
Haidinger Interferometer for Silicon Wafer TTV Measurement, Characterization and Metrology for ULSI Technology Conference
(Accessed May 31, 2023)