Patent ID: 6890771
Filing Date: 2005-05-10
Classification: G01L,G01N,H01J

Abstract:
1. A plasma processing method using a spectroscopic processing unit, comprising the steps of: a) separating spectrally plasma radiation emitted from a vacuum process chamber into component spectra; b) converting said component spectra into a time series of analogue electric signals composed of different wavelength components at a predetermined period; c) converting said analogue signals into digital signals on a predetermined-period basis; d) adding, for each of at least two predetermined plural kinds of materials within said vacuum process chamber, said digital signals of a set of wavelengths corresponding to a set of emission spectrum wavelengths intrinsic to the material; e) determining discriminatively an end point of a predetermined plasma process on the basis of said added signals obtained in said step d); and f) terminating said predetermined plasma process.