Fully automatic cassette-to-cassette contact aligner  with front and back side alignment for up to 6” & 8” wafers. With UV400 Optics and with the other hardware at VTT, the nominal resolution is 1.5 µm. Prealigner accuracy is +/- 300 µm. Chuck is moved for alignment (mask stays put), and the range of movement is only +/- 3 mm.