Edge roughness study of chemically amplified resist in low-energy electron-beam lithography using computer simulation

We investigated the line edge roughness (LER) of chemically amplified resist (CAR) in the high-sensitivity resist process in low-energy electron beam lithography (LEEBL). We have confirmed that a sub-100 nm pattern having a small line edge toughness could be obtained at the exposure dose below sub-1 muC/cm(2) for LEEBL. In order to explain the experimental results, we have proposed a resist exposure model, considering the generation yield and diffusion of secondary electrons (SEs), Based on the proposed model, we analyzed the LER for LEEBL using a simulation. When the beam blur and the acceptable LER were 30 nm (a) and 2nm (a), the acceptable exposure doses for 2-5 keV and 50keV were 0.3 muC/cm(2) and 2.5 muC/cm(2). respectively. This means that a high-sensitivity CAR process at the exposure dose below 0.5 muC/cm(2) can be achieved in LEEBL.