Abstract: A method of deprocessing damascene type integrated circuits which include copper (Cu) and tantalum nitride (TaN) layers is provided. An etch is used which includes an acetic salt in a solution with an hydroxide. The acetic salt etches the copper layer.

Abstract: A dispenser for ejecting slurry into a liquid stream so that optimum mixing s attained. This dispenser may include an elongated body having nose and main sections, the forward end of the main body section having an annular slurry receiving cavity which is located adjacent the nose. Means are provided for mounting the nose to the main body section for longitudinal movement so as to open and close the annular cavity to the liquid stream. In this manner the slurry can be ejected and dispersed into the liquid stream when the annular cavity is opened thereto. In order to obtain controlled mixing the dispenser may further include a conduit in which the elongated body is disposed.