Pedestal design for a sputter clean chamber to improve aluminum gap filling ability

A method of sputter cleaning, comprising:

• providing a pedestal formed of conducting metal having a top surface, a bottom surface, and a sidewall;
• providing a vacuum chamber having an exterior shell, wherein said pedestal is contained within said exterior shell;
• providing a layer of first insulating material formed on said top surface of said pedestal;
• providing a layer of second insulating material formed on said sidewall of said pedestal thereby forming an insulating collar on said sidewall of said pedestal;
• providing a cooling channel having an inlet end and an exhaust end formed in said pedestal;
• providing an inlet tube wherein one end of said inlet tube is connected to said inlet end of said cooling channel and said inlet tube passes through said exterior shell of said vacuum chamber;
• providing an exhaust tube wherein one end of said exhaust tube is connected to said exhaust end of said cooling channel and said exhaust tube passes through said exterior shell of said vacuum chamber;
• providing a support mechanism attached to said bottom surface of said pedestal, wherein said support mechanism passes through said exterior shell of said vacuum chamber;
• providing means to maintain a vacuum seal at the region where said inlet tube, said outlet tube, and said support mechanism pass through said exterior shell of said vacuum chamber;
• placing a substrate on said layer of first insulating material;
• and
• sputter cleaning said substrate while flowing cooling liquid through said cooling channel thereby controlling the temperature of said pedestal during said sputter cleaning.