Use the optical Microscope to measure the coordinates of Your PreMarker with respect to the Faraday Cup. Your wafer is covered with suitable markers.

  • Mount the sample stage with the wafer to the optical Microscope. Turn the locking screw 90 degree clockwise.
  • Move to the farraday cup so that the crosshair is in the center of the hole of the cup with the highest magnification. Check, if this position is close to the one in the holders table glued to the wall.
  • Rotate the sample to align the angle correction to be as close to zero as possible. (The machine accepts onlu +/- 0.2 degree!
  • Find one marker on your wafer (any marker will do, you just have to know which it is.) This is Your PreMarker.
  • Center the crosshair at this PreMarker with the same (highest) magnification of the scope.
  • Write down the X and Y coordinate of this position.