A wafer processing system for use with a driver and a material supply source, the driver being operable to generate a driving signal, the material supply source being operable to provide a material, said wafer processing system comprising: an upper confinement chamber portion having an upper confinement chamber portion inner surface (126, 526, 626, 726, 826, 926); a lower confinement chamber portion detachably disposed in contact with said upper confinement chamber portion, said lower confinement chamber portion having a lower confinement chamber portion inner surface; a confinement ring (308, 608, 708, 808, 908) removably disposed in contact with said upper confinement chamber portion inner surface and said lower confinement chamber portion inner surface, said confinement ring having a confinement ring inner surface; and an electro-static chuck having an electro-static chuck upper surface and being arranged to receive, in use, the driving signal, wherein said upper confinement chamber portion, said lower confinement chamber portion, said confinement ring (308, 608, 708, 808, 908) and said electro-static chuck are arranged such that said upper confinement chamber portion bottom surface (126, 526, 626, 726, 826, 926), said lower confinement chamber portion top surface, said confinement ring inner surface and said electro-static chuck top surface surround a plasma-forming space that is capable of receiving the material, wherein said upper confinement chamber portion, said lower confinement chamber portion, said confinement ring (308, 608, 708, 808, 908) and said electro-static chuck are operable to transform the material into a plasma when said electro-static chuck receives the driving signal, and wherein said confinement ring has a non-rectangular, c-shaped cross section. an upper confinement chamber portion having an upper confinement chamber portion inner surface (126, 526, 626, 726, 826, 926); a lower confinement chamber portion detachably disposed in contact with said upper confinement chamber portion, said lower confinement chamber portion having a lower confinement chamber portion inner surface; a confinement ring (308, 608, 708, 808, 908) removably disposed in contact with said upper confinement chamber portion inner surface and said lower confinement chamber portion inner surface, said confinement ring having a confinement ring inner surface; and an electro-static chuck having an electro-static chuck upper surface and being arranged to receive, in use, the driving signal, wherein said upper confinement chamber portion, said lower confinement chamber portion, said confinement ring (308, 608, 708, 808, 908) and said electro-static chuck are arranged such that said upper confinement chamber portion bottom surface (126, 526, 626, 726, 826, 926), said lower confinement chamber portion top surface, said confinement ring inner surface and said electro-static chuck top surface surround a plasma-forming space that is capable of receiving the material, wherein said upper confinement chamber portion, said lower confinement chamber portion, said confinement ring (308, 608, 708, 808, 908) and said electro-static chuck are operable to transform the material into a plasma when said electro-static chuck receives the driving signal, and wherein said confinement ring has a non-rectangular, c-shaped cross section.