SI-traceable calibration of line-width roughness of 25nm NanoCD standard

Abstract

SI-traceable critical dimension 3DAFM was used to characterize 25 nm NanoCD linewidth standard. The standard has a uniquely low linewidth roughness (LWR) and can be used as a benchmark during development of advanced patterning technologies. The following results were obtained: (a) Mean LWR for two 25 nm standards with uncertainty ±0.02 nm (0.95 CL). The LWR is below 0.7 nm (1s). (b) Distribution of LWR and linewidth (LW) at 3 line heights (20, 50 and 80% from the line top) along 3 mm segment of the standards. Variations are below 0.25 nm and 0.07 nm (1s) for LW and LWR, respectively. (c) Spatial power spectra of LWR of the standards. The NanoCD spectrum resembles reported earlier spectra of polycrystalline Si.