University of California Berkeley: VUV beam experiments

1. CO2 MAMA 193 nm PR RAMA NSF GOALI Interactions of Plasma/Energetic Beams with Organic Masking MaterialsGottlieb S. Oehrlein, University of Maryland College Park, DMR 0705953 Instability of 193nm Photoresist under VUV radiation University of Maryland: Plasma reactor experiments University of California Berkeley: VUV beam experiments UV/VUV radiation Material loss 193nm PR Key Result: Plasma-generated VUV radiation degrades methacrylate-based 193nm photoresist (PR) masks during plasma etch (PE), whereas previous generation PR masks are radiation stable. ~100nm 193 nm PR mask thickness reduction by plasma-generated UV/VUV measured using real time ellipsometry in conjunction with optical filters. Complementary mass spectrometry measurements confirm the VUV radiation induced material loss of CO2 at 65oC and adamantyl (not shown). Densification This GOALI project collaboration involves a multidisciplinary team of University of Maryland (plasma experiments), University of California Berkeley (beam experiments), Dow Electronic Materials (providing custom polymer materials) and Lam Research (plasma etching and characterization expertise) Approach Conclusions: Unmodified 193nm PR • Plasma UV/VUV radiation exposure of advanced 193nm PR causes detachment and removal of polymer pendant groups (lactone and adamantane) in a depth of ~100nm as quantified for the first time by real-time measurements on plasma systems, and confirmed by UV alone exposures in a beam system. Observed material modifications are in agreement with product evolution characterization during VUV only exposures. • Instability of advanced photoresist masks during exposure to plasma-generated UV/VUV radiation is found to be central to degradation of nanoscale polymer masks by plasma.

2. NSF GOALI Interactions of Plasma/Energetic Beams with Organic Masking Materials Gottlieb S. Oehrlein, University of Maryland College Park, DMR 0705953 • Our insights are the foundation of rational design of • next generation polymer materials and • novel plasma etching processes • which will minimize surface and line edge roughness of plasma transferred nano-scale patterns. Significance • Monthly meetings of academic and industrial partners - University of Maryland, University of California Berkeley, Lam Research and Dow Electronic Materials, to discuss latest results and make systematic progress. • Involvement of undergraduate students Nirav Kumar and Sivan Shachar at University of Maryland. • Student presentations at National meetings, e.g. AVS, along with numerous invited presentations by PIs at international conferences. • F. Weilnboeck, summer internship at Lam Research (2009). • Significant progress in development of experimental techniques, simulations and data analysis methodologies to enable improved and unambiguous scientific insights. Education and Outreach Graduate Student Ting-Ying Chung working on our beam system at UC Berkeley. Graduate Student FlorianWeilnboeck working with undergraduate student Nirav Kumar on a plasma reactor at University of Maryland