Mask holder for microlithography exposure
AssigneeNikon Corporation
InventorNoriyuki Hirayanagi
Life of this patent
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Abstract
Mask holders are disclosed for holding a mask used during a microlithographic exposure. The mask holder comprises an outer frame and an inner frame. The outer frame contacts the periphery of a main surface of the mask to hold the mask. The inner frame is connected to the outer frame, and contacts an inner portion of said main surface of the mask to hold the mask. The mask holder can include one or more electrostatic and/or vacuum chucks, a thermally conductive material that contacts the mask whenever the mask is being held by the mask holder, and/or an electrically conductive material to discharge accumulated electrical charge on the mask during use.
Claims12
A mask holder for holding a microlithography mask defining a pattern to be projection-transferred to a sensitive substrate, the mask comprising a periphery, an inner region, and a main surface, the mask holder comprising an outer frame and an inner frame connected to the outer frame, the outer frame being adapted to contact the periphery of the main surface of the mask to hold the mask and the inner frame being adapted to contact the inner region of the main surface of the mask so as to provide support for the inner region of the mask when the mask is being held by the mask holder.
Dependencies are inferred from the claim text.