EUV-induced hydrogen plasma: pulsed mode operation and confinement in scanner

In recent years, EUV lithography scanner systems have entered high-volume manufacturing for state-of-the-art integrated circuits, with critical dimensions down to 10 nm. This technology uses 13.5-nm radiation, which is shaped and transmitted through a near-vacuum H2 background gas. gas excited into low-density plasma by the as generated in pulsed mode operation laser-produced source. Thus, confinement created walls mirrors within system, reductive environment that must be understood detail maximize mirror transmission over lifetime minimize molecular particle contamination scanner. addition irradiated mirrors, reticle, wafer, radical load surrounding construction materials also considered. We provide an overview of EUV-induced context. Special attention given parameters confined geometry, such found area near reticle. It shown resulting contributions from secondary electron emission delay formation sheath thereby reduce peak ion energies below sputtering threshold materials. Furthermore, pulse period shorter than decay time plasma, consists quasi-steady-state cold periodic transient peaks energy flux. terms modeling, this means no assumptions can made on distribution functions (Monte-Carlo) particle-in-cell (PIC) model needed. present extension PIC approach complex three-dimensional geometries multiple pulses using hybrid PIC-diffusion approach. Also, translation these specific off-line setups aspects included make meaningful laboratory are discussed.