Patent ID: 7838848

Claim:
A patterning device holding apparatus for use in charged particle beam imaging, said patterning device comprising a patterning area at the center and a margin area surrounding said patterning area, comprising: a support platform unit for supporting said patterning device thereon, said support platform unit comprising a plurality of first positioning projections; a gripper unit for fixing said patterning device in place through rotation of said gripper unit about a pivot substantially parallel with a center axis of a rolling member set at a base portion of said gripper unit, said gripper unit further comprising a head portion and a plurality of second positioning projections disposed on said head portion, wherein when said patterning device is fixed in place, said plurality of first positioning projections abut against two edges of said patterning device and said plurality of second positioning projections abut against the other two edges of said patterning device.