Diluted low dielectric constant materials as bottom antireflective coating layers for both KrF and ArF lithography processes

In this paper, we report on a bottom antireflective coating (BARC) layer for both KrF and ArF lithography processes. The antireflective layers are composed of diluted low-dielectric constant materials, such as bisbenzo(cyclobutene) (BCB), fluorinated poly(arylene)ether (FLARE) and SiLK. By adding an optimized thickness of diluted low-dielectric constant materials, the reflectance of less than 1% at the resist/silicon substrate interface can be achieved. Diluted low-dielectric constant materials also have great potential to be used as BARC layers on various highly-reflectance substrates for metalinterconnect applications. Using this structure, it is easy to reduce reflectance without adding an extra BARC layer for patterning low-dielectric materials. After the lithography procedure, the diluted low-dielectric constant layer need not be removed.