X-ray lithography processing at CXrL from beamline to quarter-micron NMOS devices

In this paper we present the activities at the Center for X-ray Lithography (CXrL) that are dedicated to applying x-ray lithography to 0.25 μm processing. We first present the results of optimizing the parameters of the x-ray resist, AZ-PF 514, to achieve 0.25 micron features with variations of less than 10%; second, we discuss the properties of an exposure station (ES3) that feeds the in-house built aligner; third, we present the novel in-house built Two State Aligner (TSA) and its ability to achieve < 32 nm registration error; fourth, we present a developed fabrication process that produces masks with the required membrane stress, optical transparency, and mask flatness; and finally, we present the integration of all the above subprocesses by showing preliminary results from the in-progress 0.25 μm NMOS device run. The requirements and results of each sub-process are discussed and judged according to the 0.25 μm error budget goals that were initially set for 1997.