The present disclosure herein relates to an apparatus and method for plating a substrate, and more particularly, to a substrate plating apparatus and method for performing a metal plating process on a semiconductor substrate.
Copper (Cu) having low electrical resistance and high electromigration resistance than those of aluminium (Al) or an Al alloy is used in recent years as a material for forming an interconnection circuit on a semiconductor substrate. Generally, Cu is filled into an interconnection pattern trench formed in a surface of the substrate to form a Cu interconnection. Various techniques for forming the Cu interconnection are known. For example, the techniques may include chemical vapor deposition (CVD), sputtering, plating, etc. However, the CVD process requires relatively high manufacturing costs when the Cu interconnection is formed. Also, according to the sputtering process, it is difficult to fill Cu or its alloy into the interconnection pattern trench in case where the interconnection pattern trench has a high aspect ratio. On the other hand, the plating process has improved efficiency because Cu or its alloy is deposited on the substrate to form the Cu interconnection.
FIG. 1A is a schematic view of a typical substrate plating apparatus. FIG. 1B is an enlarged view illustrating a portion “a” of FIG. 1A. As illustrated in FIG. 1A, a typical substrate plating apparatus 10 includes a substrate support member 11 supporting a substrate W to allow a surface to be plated (hereinafter, referred to as a plating surface) of the substrate W to look down and a plating bath 15 disposed below the substrate support member 11 and including a positive electrode 12 and an ion exchange membrane 13. The substrate W is supported by the substrate support member 11 to allow the plating surface to look down and is immersed into a plating solution.
According to the typical substrate plating apparatus 10, since the substrate W transferred in a state in which the plating surface looks up should be reversed to allow the plating surface to look down in order that the substrate W is supported by the substrate support member 11, a separate unit for reversing the substrate W is required. Also, as illustrated in FIG. 1B, due to a chemical reaction during the plating process or the rotation of the substrate support member 11, bubbles 27 may occur in the plating solution. Thus, the generated bubbles 27 rise up by buoyancy to stay on a contact hole 25 for interconnection or a trench 26. If the bubbles 27 staying on the contact hole 25 for interconnection or the trench 26 are not removed, a defect pattern of the substrate W may occur during the plating process.