RESOLUTION ENHANCEMENT TECHNIQUES COMBINING FOUR BEAM INTERFERENCE-ASSISTED LITHOGRAPHY WITH OTHER PHOTOLITHOGRAPHY TECHNIQUES

摘要

Methods and systems are disclosed that provide multiple lithography exposures on a wafer, for example, using interference lithography and optical photolithography. Various embodiments may balance the dosage and exposure rates between the multiple lithography exposures to provide the needed exposure on the wafer. Other embodiments provide for assist features and/or may apply resolution enhancement to various exposures. In a specific embodiment, a wafer is first exposed using optical photolithography and then exposed using interference lithography.