APPARATUS FOR EXPOSING WAFER

摘要

An apparatus for exposing a wafer is provided to transfer certain light on a wafer through a changed optimal focusing position by moving a wafer stage to the optimal focusing position. A light source(10) emits a light exposing a wafer(15). A reticle(20) is mounted on a lower end of the light source. A certain pattern to be transferred to the wafer is formed on the reticle. An optical system(30) is mounted on a lower end of the reticle. The optical system measures an optimal focusing distance to irradiate light so that the light is irradiated on a certain position as certain amount in order to transfer the pattern formed on the reticle to the wafer. A wafer stage(40) supports the wafer and moves the wafer to the optimum focusing position measured in the optical system to a vertical direction. A driving unit(50) drives the wafer stage.