CHARGING EFFECTS ON TRILEVEL RESIST WITH AN E-BEAM LITHOGRAPHY SYSTEM

The charging effect on a trilevel resist system was investigated with a variable-shaped electron beam (e-beam) lithography system. A test pattern which consists of two-dimensionally arrayed marks was exposed on the trilevel resist and measured by the e-beam. A method evaluating the correlation of repetitive measurement errors due to charging has been developed. This evaluation method was characterized such that the repetitive measurement and charging process occurred simultaneously without a conductive coating on the resist. The evaluation method of the charging process at 20 and 30 kV is demonstrated in this article. The resist result is different from that of silicon dioxide, and these phenomena are discussed together with the associated discharging processes.