Effects of mask absorber thickness on printability in EUV lithography with high resolution resist
Konferenz: EMLC 2009 - 25th European Mask and Lithography Conference
12.01.2009 - 15.01.2009 in Dresden, Germany
Tagungsband: EMLC 2009
Seiten: 12Sprache: EnglischTyp: PDFPersönliche VDE-Mitglieder erhalten auf diesen Artikel 10% Rabatt
Kamo, Takashi; Aoyama, Hajime; Tanaka, Toshihiko; Suga, Osamu (MIRAI - Semiconductor Leading Edge Technologies, Inc. (Selete), 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569, Japan)
The effects of mask absorber thickness on printability in EUV lithography was studied from the viewpoint of lithographic requirements which can give high imaging contrast and reduce shadowing effect. From lithography simulation, optimum thickness range of mask absorber (LR-TaBN) for exposure latitude was predicted, and the effect of absorber thickness on MEF and H-V (Horizontal - Vertical) printed CD difference was determined using resist blur model. From printability experiments with a Small Field Exposure Tool (SFET) and with high resolution resist, optimum thickness of LR-TaBN absorber was demonstrated. When thinner absorber mask is employed in EUVL for ULSI chip production, it becomes necessary to introduce EUV light shield area in order to suppress the leakage of EUV light from neighboring exposure shots. Resist pattern CD change from the neighboring exposure shots was estimated by lithography simulation.