Patterning of SnO2/SnTe binary mask structure for extreme ultra-violet lithography using inductively coupled H2/Ar plasmas
作者单位：Department of Advanced Materials Science and EngineeringSungkyunkwan University SKKU Advanced Institute of NanotechnologySungkyunkwan University Department of PhysicsInha University Photomask TeamMemory DivisionSemiconductor BusinessSamsung Electronics Co.Ltd.
会议名称：《第三届微电子及等离子体技术国际会议》
会议日期：2011年
学科分类：080903[工学-微电子学与固体电子学] 080901[工学-物理电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080401[工学-精密仪器及机械] 080501[工学-材料物理与化学] 0804[工学-仪器科学与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0803[工学-光学工程]
关 键 词：EUVL ESL(Etch Stop Layer) SnTe SnO2
摘 要：Currently,extreme ultra-violet lithography（EUVL） is the major candidate of next generation lithography for below 25 nm technology *** fabrication is quite different from the transmissive optics of conventional photolithography masks because of the use of new reflective optics due to absorption of UV light by the quartz *** investigated selective etching of SnTe（tin tellurium alloy） as a new absorber material having high EUV absorbance due to its large extinction *** additional SnO2（tin oxide） layer as an anti reflection coating（ARC） required to reduce the reflectance of the absorber layer was selectively ***,patterning process of the binary mask structure of SnO2（anti reflection coating）/SnTe（absorber layer）/Ru（capping/etch stop layer）/Mo-Si multilayer（reflective layer）/Si（substrate） was *** infinitely high selectivity of the SnTe layer to the Ru ESL is required due to the ultrathin nature of the Ru layer,the various etch parameters were varied in the inductively coupled H2/Ar plasmas in order to find the process window required for the infinitely high etch selectivity of the SnTe layer to Ru layer during one-step etching of SnO2/SnTe stacked *** results showed that the gas flow ratio and self-bias voltage Vdc played an important role in determining the process window for the ultra-high selective etching even with increasing overetch *** high EUV-absorbance SnTe layer,patternable by a dry process,would allow a smaller absorber thickness,which can mitigate the geometric shadowing effects observed during exposure of EUV by using high performance binary EUVL masks.