Patent ID: 6936157
Filing Date: 2005-08-30
Classification: G01N

Abstract:
1. A method for determining concentration(s) of a suppressor and/or an accelerator in a sample metal plating solution that contains both the suppressor and the accelerator, said method comprising the steps of: (a) preparing a plurality of calibration solutions, each of which contains the suppressor and the accelerator in different, known concentrations; (b) measuring electroplating potential that is characteristic of a calibration solution; (c) calculating concentrations of the suppressor and the accelerator in said calibration solution, according to Pulsed Cyclic Galvanostatic Analysis of the measured electroplating potential of said calibration solution; (d) repeating steps (b) to (c) for each calibration solution, to obtain calculated concentrations of the suppressor and the accelerator in each calibration solution; (e) determining correction coefficients for the suppressor and/or the accelerator, based on the known concentrations of the suppressor and/or the accelerator and the calculated concentrations of the suppressor and the accelerator in the calibration solutions; (f) measuring electroplating potential that is characteristic of the sample metal plating solution; (g) calculating concentrations of the suppressor and the accelerator in said sample metal plating solution, according to Pulsed Cyclic Galvanostatic Analysis of the measured electroplating potential of said sample metal plating solution; and (h) determining corrected concentration(s) of the suppressor and/or the accelerator in the sample metal plating solution, based on the calculated concentrations of the suppressor and the accelerator in said sample metal plating solution and the correction coefficients determined in step (e) for the suppressor and/or the accelerator.