Susan can be considered superior to equivalent state of the art equipment due to the following reasons:

• The concept allows a significant increase of the measurement speed.
• Air bearing guideways allow a frictionless operation while safeguarding a high stiffness.
• An innovative and hitherto for these applications unused drive system combines a high bandwidth with low maintenance and clean room feasibility.
• The upgraded system will be the first on the market allowing high lateral resolution measurements combined with geometrical measurements.
• The wafer will be measured on the whole wafer surface due to wafer rotation
• The measurement is conducted simultaneous on both sides with the wafer mounted vertically to avoid any errors due to gravity.