| 摘要 |
PURPOSE:To improve sensitivity and accuracy in the detection of the end of the dry etching of Al with SiCl4 as a principal etching gas, by detecting the end in accordance with a change in the total intensity of a plurality of plasma emission spectra in a specified wavelength range. CONSTITUTION:In the dry etching of Al with SiCl4 as a principal etching gas, the intensity of plasma light P emitted by exciting the etching gas is measured with a photoelectric transducing element 12 having sufficient sensitivity in the wavelength range of 300-400nm through a light transmitting window 7. By the measurement the total intensity of a plurality of plasma emission spectra in the wavelength range of 300-440nm is measured. The intensity is suddenly increased at the beginning Es of etching, and it is considerably reduced at the time Ee when parts of an Al film corresponding to holes to be pierced are thoroughly removed. The time Ee is considered to be the end of etching. |
