SYSTEM AND METHOD FOR LASER BEAM EXPANSION WITHOUT EXPANDING SPATIAL COHERENCE

摘要

PURPOSE: A system and a method are provided to expand emitted light from a laser beam without changing spatial coherence or producing speckle. CONSTITUTION: A system(100) expands a light(102) emitted from a laser(104) without changing spatial coherence of the light and that substantially eliminates speckle patterns. The laser(104) is an excimer or deep UV excimer laser. The light(102) is received by a multiplexer(106) in a beam conditioner(108). The beam conditioner outputs light to illumination optics(110), which in turn transmits light through a mask or reticle(112) onto a substrate(116) via projection optics(114). By using the pre-expansion system, speckle and other problems related to conventional expansion system is substantially eliminated.