Patent ID: 6689686
Filing Date: 2004-02-10
Classification: C25D

Abstract:
A method for forming a conductive layer on an outer surface of a substrate, comprising:providing a semiconductor substrate with an outer surface; placing the outer surface of the semiconductor substrate in contact with a solution comprising a conductive material, passing electrical current through the solution and the semiconductor substrate so as to cause the conductive material to deposit on the outer surface of the semiconductor substrate under an electromotive force caused by the electrical current; varying the level of the electrical current from a first current level to a second current level to provide for differing rates of deposition of the conductive material on the outer surface of the semiconductor substrate, wherein the change in the current level from the first current level to the second current level is done in a smooth fashion so that substantially instantaneous changes in current level are avoided to reduce rapid changes in the electrical field near the area where the conductive material is adhering to the outer surface of the semiconductor; and varying the current level by smoothly reversing the flow of current so as to deplate the conductive material from the outer surface of the semiconductor substrate without rapid transient changes in the electrical field for a selected period of time.