| abstract |
PROBLEM TO BE SOLVED: To provide a processing condition capable of realizing high-precision etching with high selectivity without causing film damage in a low dielectric constant film (Low-k film, for example, SiOCH). In a BARC etching step, a groove or a hole is processed to be narrower than a pattern dimension, and etching is performed under a high mask selection ratio condition including N 2 or O 2 . Then free of N 2 or O 2, high mask containing N 2 or O 2 which reduces the bias output to be applied to the wafer performing isotropic etching, or than the pattern dimension is processed slightly thinner grooves or holes Isotropic etching is performed periodically by reducing the selection ratio condition and the bias output applied to the wafer without containing N 2 or O 2 . [Selection] Figure 6 |