Hiroshi Saeki - A precision table for ultrahigh vacuum made of aluminum alloys

Version 1

      Publication Details (including relevant citation   information):

      J. Vac. Sci. Technol. A 6(5), 2883 - 2886 (1988).

      This article was presented at the 34th National Symposium of the   AVS, Anaheim, U.S.A., 1987.


            07.30.Kf              Vacuum chambers, auxiliary apparatus, and materials      
            85.40.Hp              Lithography, masks and pattern transfer      


      Recently an ultrahigh vacuum environment has been necessary to   reduce impurities in the production of high‐density integrated   circuits. In particular, tables permitting precise positioning   with low outgassing rates have been required for thin‐film   processing equipment and surface analysis systems using spot   beams. An XY–θ three‐axis table made of aluminum   alloys with a special surface treatment for ultrahigh vacuum   environments has been developed. The stroke of the X and Y axes is 75 mm,   and the rotational range of the θ axis is 360°. The X and Y axes are driven   by built‐in stepping motors, connected directly to aluminum alloy   ballscrews. The stator of the motor is made using stainless‐steel   sheath cable. The screws and nuts of the ballscrews are coated   with TiC, and the balls are coated with Ag. The characteristics   of the table have been investigated in atmosphere before and   after baking. The measured error motions for the X axis were pitch   ±2.3 μm/75 mm and yaw±1.4 μm/75 mm; and for the Y axis were pitch   ±0.78 μm/75 mm and yaw ±0.22 μm/75 mm. The resolution and   repeatability for the X and Y axes was 15 μm ±2 μm/pulse, and for   the θ axis was 1.8° ±0.09°/pulse. The mechanical characteristics   were maintained after baking. The table moved in an ultrahigh   vacuum environment of the order of 1011 Torr as it had in atmosphere.

      Address (URL): http://avspublications.org/jvsta/resource/1/jvtad6/v6/i5/p2883_s1