| US 7,455,790 B2 | ||
| Emission spectroscopic processing apparatus and plasma processing method using it | ||
| Tetsunori Kaji, Tokuyama (Japan); Shizuaki Kimura, Kudamatsu (Japan); Tatehito Usui, Chiyoda (Japan); and Takashi Fujii, Coppell, Tex. (US) | ||
| Assigned to Hitachi, Ltd., Tokyo (Japan); and Hitachi High-Technologies Corporation, Tokyo (Japan) | ||
| Filed on Mar. 10, 2005, as Appl. No. 11/75,803. | ||
| Application 10/659394 is a division of application No. 10/090759, filed on Mar. 06, 2002, granted, now 6,716,300. | ||
| Application 11/075803 is a continuation of application No. 10/659394, filed on Sep. 11, 2003, granted, now 6,890,771. | ||
| Claims priority of application No. 2001-364626 (JP), filed on Nov. 29, 2001. | ||
| Prior Publication US 2005/0155952 A1, Jul. 21, 2005 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. H01L 21/302 (2006.01) | ||
| U.S. Cl. 216—67 [438/9; 156/345.24; 216/60] | 6 Claims |
| 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) adding together analogue signals of the different wavelength components;
d) converting a plurality of plural added said analogue electric signals into digital signals on a predetermined period basis;
e) adding, for each of at least two of 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;
f) determining discriminatively an end point of a predetermined plasma process on a basis of said added signals obtained in
said step e); and
g) terminating said predetermined plasma process.
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