Patents Examined by J. Lund
  • Patent number: 5906684
    Abstract: In a method of holding a substrate and a substrate holding system where, the amount of foreign substances on the back surface of the substrate can be decreased and only a small amount of foreign substances transferred from a mounting table to the substrate. For this purpose, the substrate holding system has a ring-shaped leakage-proof surface providing a smooth support surface on the specimen table corresponding to the periphery of the substrate, a plurality of contact holding portions which bear against the substrate on the specimen table between the corresponding position to the periphery of the substrate and the corresponding position to the center of the substrate, and electrostatic attraction means for fixing the substrate by contacting the back surface of the substrate to the ring-shaped leakage-proof surface and the contact holding portions.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: May 25, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Naoyuki Tamura, Kazue Takahashi, Youichi Ito, Yoshifumi Ogawa, Hiroyuki Shichida, Tsunehiko Tsubone