White light interferometer for high precision wafer measurement | interferoMETER IMS5420-TH

The IMS5420 is a high-performance white light interferometer for non-contact thickness measurement of monocrystalline silicon wafers. The controller has a broadband superluminescent diode (SLED) with a wavelength range of 1,100 nm. This enables the thickness measurement of undoped, doped and highly doped SI wafers with only one measuring system and signal stability of less than 1 nm. Depending on the field of application, sensors with large offset distance and with air purge system are available.

Precise wafer thickness measurement

Due to the optical transparency of silicon wafers in the wavelength range of 1,100 nm, the IMS5420 interferometers can precisely detect the thickness. In this wavelength range, both undoped silicon and doped wafers provide sufficient transparency. Therefore, wafer thicknesses up to 1.05 mm can be detected. The measurable thickness of the air gap is even up to 4 mm.