Investigating line-edge roughness in calixarene fine patterns using Fourier analysis

The line-edge roughness (LER) of patterns of negative-tone electron-beam resists. methyl-acetoxy calix[n]arene (n = 6-8), was investigated using Fourier analysis. LER Measurements were carried out by determining the intensity peaks of the pattern edges in scanning electron micrographs. The Fourier analysis showed that the roughness of the resist materials produced large peaks in the 10 to 100 nm wavelength range. The total intensity of LER spectra clearly depended on the electron dose and the "n" number of the calixarene resists. The smallest LER was observed in the calix[7]arene films, In contrast, the calix[6]arene films had a relatively large intensity in their Fourier spectra, X-ray diffraction measurements (XRD) revealed crystallization in the calix[6]arene films and an amorphous phase in the calix[7]arene and calix[8]arene films.