Immersion lithography system using a sealed wafer bath

摘要

Immersion lithography system and method using a sealed wafer bottom are described. One embodiment is an immersion lithography apparatus comprising a lens assembly comprising an imaging lens and a wafer stage for retaining a wafer beneath the lens assembly, the wafer stage comprising a seal ring disposed on a seal ring frame along a top edge of the wafer retained on the wafer stage, the seal ring for sealing a gap between an edge of the wafer and the wafer stage. The embodiment further includes a fluid tank for retaining immersion fluid, the fluid tank situated with respect to the wafer stage for enabling full immersion of the wafer retained on the wafer stage in the immersion fluid and a cover disposed over at least a portion of the fluid tank for providing a temperature-controlled, fluid-rich environment within the fluid tank fluid-rich environment within the fluid tank.

主权项

1. An immersion lithography apparatus comprising:
a lens assembly comprising an imaging lens; a wafer stage for retaining a wafer beneath the lens assembly; a fluid tank for retaining immersion fluid, the fluid tank situated with respect to the wafer stage for enabling immersion of the wafer retained on the wafer stage in the immersion fluid; a trench disposed around the fluid tank for capturing immersion fluid overflowing from the fluid tank during operation via at least one overflow hole disposed in a wall of the fluid tank, wherein the wall of the fluid tank is configured so that it may be moved with respect to the fluid tank to allow the immersion fluid to flow out of the fluid tank and into the trench; and a cover disposed over at least a portion of the fluid tank for providing a temperature-controlled, fluid-rich environment within the fluid tank.