Online Monitoring of Copper Damascene Electroplating Bath by Voltammetry: Selection of Variables for Multiblock and Hierarchical Chemometric Analysis of Voltammetric Data

Table 3

Preliminary estimation of the ranges of points of staircase voltammogram, variables , of Figure 1 selected based on results of Figure 2. The potentials are expressed versus reference electrode.

Data range index,	Signal	Range of voltammogram, variables	Width, J	​; mV	​; mV	Average R (see (1)),; whole scan decomposition	Average R (see (1)), individual range decomposition
	Reduction	1401–1430	30	−268	−338	0.9414	0.9804
	Oxidation	1476–1496	21	122	322	0.9204	0.9309
	Reduction	1785–1826	42	−197	−287	0.9592	0.9663
	Oxidation	1865–1888	24	102	333	0.9078	0.9085
	Reduction	2173–2219	47	−168	−268	0.9379	0.9542
	Oxidation	2256–2279	24	102	333	0.8871	0.9005
	Reduction	2562–2612	51	−208	−248	0.9110	0.9455
	Oxidation	2645–2670	26	82	333	0.8599	0.8895
	Reduction	2952–3005	54	−137	−228	0.8867	0.9375
	Oxidation	3038–3062	25	102	343	0.8518	0.8858
	Reduction	3344–3399	56	−148	−198	0.8703	0.9351
	Oxidation	3428–3454	27	92	353	0.8447	0.8755
	Reduction	3734–3793	60	−134	−168	0.8564	0.9280
	Oxidation	3819–3846	28	92	363	0.8436	0.8712