A four-axis positioning system intended for 200 and 300-mm wafer inspection features brushless digital servo-control for all four axes. The XY table is based on a high-precision linear-motor stage with 100-nm resolution position feedback. The Z axis has a direct-reading, noncontacting vertical encoder with various resolution options down to 2 nm. The Theta axis is integrated into the Z axis with a direct-drive brushless servo and high-resolution rotary encoder. The servo-control is a Micromatic-5, four-axis version including a DSP motion controller and high-powered digital servo-amplifiers, supplied as a single enclosure control with RS-232/RS-422 port or PC-supported card. X travel ranges from 200 to 1,000 mm, Y travel goes from 100 to 600 mm, and Z travel ranges from 10 to 24 mm. Theta rotation range is 2 to 360?.

Nutec Components Inc., 100 Jefryn Blvd., Deer Park, NY 11729, (631) 242-1225.