Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
69 words
A method of monitoring a plasma process which comprises (a) optically monitoring a plurality of preselected emission spectra developed by a plasma in a plasma chamber, (b) amplifying and digitizing a plurality of spectra signals of said spectra, (c) weighting and summing said signals to form a composite function, and (d) comparing the slope of the composite function to a predetermined value to determine preselected conditions within said plasma.
Claim 2
Independent Claim
69 words
A method of monitoring a plasma process which comprises (a) optically monitoring a plurality of preselected emission spectra developed by a plasma in a plasma chamber, (b) amplifying and digitizing a plurality of spectra signals of said spectra, (c) weighting and summing said signals to form a composite function, and (d) comparing the slope of the composite function to a predetermined value to determine preselected conditions within said plasma.
Claim 3
Dependent Claim
21 words
A method according to claim 1 wherein a D.C. bias channel of a cathode within said plasma chamber is also monitored.
Claim 4
Dependent Claim
24 words
A method according to claim 1 wherein the step of forming a composite includes forming a weighted sum of said plurality of spectral components.
Claim 5
Dependent Claim
24 words
A method according to claim 1 wherein said composite of said plurality of parameters includes a weighted sum of at least four spectral components.
Claim 6
Dependent Claim
34 words
A method according to claim 1 wherein said step of comparing is repeated a plurality of times and wherein endpoint is determined after a number of consecutive comparisons indicate endpoint conditions in said plasma.
Claim 7
Independent Claim
58 words
A method of monitoring the endpoint of a plasma etch process in a plasma etch system which comprises (a) collecting a plurality of digital emission signals from said plasma, (b) calculating a composite emission curve from said signals by weighting and summing said signals, and (c) determining when the slope of said composite curve exceeds a predetermined slope.
Claim 8
Independent Claim
58 words
A method of monitoring the endpoint of a plasma etch process in a plasma etch system which comprises (a) collecting a plurality of digital emission signals from said plasma, (b) calculating a composite emission curve from said signals by weighting and summing said signals, and (c) determining when the slope of said composite curve exceeds a predetermined slope.
Claim 9
Dependent Claim
23 words
A method according to claim 6 wherein said signals are obtained from a plurality of portions of an optical spectrum of said plasma.
Claim 10
Dependent Claim
35 words
A method according to claim 6 further comprising monitoring the D.C. bias of a cathode within said plasma etch system; and forming said composite using both said plurality of spectral components and said D.C. bias.
Claim 11
Dependent Claim
23 words
A method according to claim 6 wherein said step of calculating the composite further includes removing the background level from said weighted sum.
Claim 12
Dependent Claim
21 words
A method according to claim 9 wherein said step of calculating the composite further includes filtering undesired components from said composite.
Claim 13
Dependent Claim
49 words
A method according to claim 9 wherein said step of calculating the composite includes; summing said time related sum function over time to develop a time related background function; and subtracting said time related background function from said time related sum function to develop a time related offset function.
Claim 14
Dependent Claim
35 words
A method according to claim 11 wherein said step of calculating the composite includes; performing a notch filter function on said time related offset function to remove undesired components from said time related offset function.