Patent ID: 7239161

Claim:
A gantry-type XY stage comprising: a granite plate; a pair of posts made of a first composite material having a Young's modulus of 200 GPa or more, disposed on said granite plate, and spaced apart from one another in a first direction parallel to a top of said granite plate for movements in a second direction intersecting with the first direction; a beam made of a second composite material having a Young's modulus of 200 GPa or more, extended between said pair of posts; a movement base disposed for movements in the first direction relative to said beam; said beam is a hollow body comprising a shell formed with a first hole through a top thereof, and said gantry-type XY stage comprises: a linear guide bearing for guiding movements of said movement base which is made of a metal or an alloy, disposed on the top of said beam, and formed with a second hole at a position in alignment to said first hole; a backing member made of a metal or an alloy, disposed at a position opposite to said linear guide bearing across said shell within said beam, and formed with a third hole at a position in alignment to said first hole; and a securing member for securing said linear guide bearing to said beam through said second hole, said first hole and said third hole.