Adding static printing capabilities to the EUV phase-shifting point diffraction interferometer
While interferometry is routinely used for the characterization and alignment of lithographic optics, the ultimate performance metric for these optics is printing in photoresist. Direct comparison of imaging and wavefront performance is also useful for verifying and improving the predictive power of wavefront metrology under actual printing conditions. To address these issues, static, small-field printing capabilities are being added to the extreme ultraviolet (EUV) phase-shifting point diffraction interferometer (PS/PDI) implemented at the Advanced Light Source at Lawrence Berkeley National Laboratory. This Sub-field Exposure Station (SES) will enable the earliest possible imaging characterization of the upcoming Engineering Test Stand (ETS) Set-2 projection optics. Relevant printing studies with the ETS projection optics require illumination partial coherence with {sigma} of approximately 0.7. This {sigma} value is very different from the coherent illumination requirements of the EUV PS/PDI and the coherence properties naturally provided by synchrotron undulator beamline illumination. Adding printing capabilities to the PS/PDI experimental system thus necessitates the development of an alternative illumination system capable of destroying the inherent coherence of the beamline. The SES is being implemented with two independent illuminators: the first is based on a novel EUV diffuser currently under development and the second is based on a scanning mirror design. Here we describe the design and implementation of the new SES, including a discussion of the illuminators and the fabrication of the EUV diffuser.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Director, Office of Science. Office of Basic Energy Studies (US)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 789132
- Report Number(s):
- LBNL-46938; R&D Project: 509201; TRN: US0111395
- Resource Relation:
- Conference: SPIE's 26th Annual International Symposium on Microlithography, Santa Clara, CA (US), 02/25/2001--03/02/2001; Other Information: PBD: 1 Mar 2001
- Country of Publication:
- United States
- Language:
- English
Similar Records
Extreme ultraviolet lithography: A few more pieces of the puzzle
Dual-domain lateral shearing interferometer