A plasma processing chamber (250, 300, 400) for generating plasma, the plasma processing chamber comprising: a powered electrode (252, 309, 404) configured to receive a wafer or a substrate; a first grounded electrode (260, 302, 406) disposed opposite to said powered electrode, wherein said plasma is configured to be generated between said powered electrode and said first grounded electrode; a second grounded electrode (264, 306, 416) surrounding said first grounded electrode; at least one confinement ring configured to confine said plasma; a third grounded electrode (268, 308, 418), wherein the third grounded electrode is adjacent to powered electrode (252, 309, 404), wherein said third grounded electrode (268, 308, 362) being disposed below said focus ring such that said focus ring is disposed between said second grounded electrode (264, 306, 416) and said third grounded electrode; a first adjustable coupling to ground circuit (262, 304, 408) electrically coupled to said first grounded electrode, said first grounded electrode being electrically coupled to a ground through said first adjustable coupling to ground circuit, said first adjustable coupling to ground circuit configured to modify an impedance of said first grounded electrode, wherein said first adjustable coupling to ground circuit (262, 304) comprises at least one capacitor (262, 304, 356, 410); and a second adjustable coupling to ground circuit electrically coupled to said second grounded electrode (264, 306) and/or a variable capacitor is electrically coupled to said third grounded electrode (268, 308), or an inductor is electrically coupled to said third grounded electrode. a powered electrode (252, 309, 404) configured to receive a wafer or a substrate; a first grounded electrode (260, 302, 406) disposed opposite to said powered electrode, wherein said plasma is configured to be generated between said powered electrode and said first grounded electrode; a second grounded electrode (264, 306, 416) surrounding said first grounded electrode; at least one confinement ring configured to confine said plasma; a third grounded electrode (268, 308, 418), wherein the third grounded electrode is adjacent to powered electrode (252, 309, 404), wherein said third grounded electrode (268, 308, 362) being disposed below said focus ring such that said focus ring is disposed between said second grounded electrode (264, 306, 416) and said third grounded electrode; a first adjustable coupling to ground circuit (262, 304, 408) electrically coupled to said first grounded electrode, said first grounded electrode being electrically coupled to a ground through said first adjustable coupling to ground circuit, said first adjustable coupling to ground circuit configured to modify an impedance of said first grounded electrode, wherein said first adjustable coupling to ground circuit (262, 304) comprises at least one capacitor (262, 304, 356, 410); and a second adjustable coupling to ground circuit electrically coupled to said second grounded electrode (264, 306) and/or a variable capacitor is electrically coupled to said third grounded electrode (268, 308), or an inductor is electrically coupled to said third grounded electrode.