Abstract: A method of improving the uniformity of etching of a film on an article, the method including the steps of immersing the article containing the film into a tank of etchant, rotating the article while in the etchant for a desired amount of time so as to cause improved uniformity of etching of the film compared to etching without rotating the article, and removing the article from the tank of etchant. In a preferred embodiment of the invention, the article is a semiconductor wafer.

Abstract: Form a solder connector on a semiconductor device starting with a first step of forming at least one dielectric layer over a doped semiconductor substrate. Then form a hole through the dielectric layer down to the semiconductor substrate. Form a metal conductor in the hole. Form intermediate layers over the metal conductor and the dielectric layer. Then form a tapered opening down to the surface of the metal conductor. Form BLM layers including a titanium-tungsten (TiW) layer over the metal conductor and the dielectric layer with the remainder of the BLM layers being formed over the TiW layer. Form a mask over the top surface of the BLM layers with a patterning through hole located above the metal conductor exposing a portion of the surface of the BLM layers. Plate a C4 solder bump on the BLM layers in the patterning hole. Remove the mask. Wet etch away the BLM layers aside from the solder bump leaving a residual TiW layer over the dielectric layer.