In this work, an Amphibian XIS interference mini-stepper is used to synthesize the aerial image of 90nm dense line/space pattern produced by an ASML TWINSCAN /1150i immersion scanner, using a second single beam exposure to demodulate the first 100% modulated interference exposure. The experimental data from the scanner and the demodulated interference exposure have near identical exposure latitude and LER (line edge roughness). Whilst the synthetic defocus data also shows a good degree of correlation with the projection data, the level of agreement is a little lower. Overall agreement is good, suggesting that the use of the synthetic aerial image approach is a useful screening tool for photoresists prior to testing on full field scanner system. This technique can be used to predict the performance of future projection tools, allowing cycles of learning in resist development prior to scanner availability.

Date of creation, presentation, or exhibit



Proceedings of the SPIE Conference on Optical Microlithography XIX, vol. 6154, 2006 Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type

Conference Proceeding

Department, Program, or Center

Microelectronic Engineering (KGCOE)


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