Mushroom shaped bump on repassivation

Abstract

Systems, methods and/or techniques for mushroom shaped bump on repassivation are described. A method of forming a chip scale package may include applying a first photoresist layer over a semiconductor wafer, developing away a portion of the first photoresist layer to define a cylindrically shaped template with substantially vertical side walls, and plating metal at least partially within the template to form a bump. The bump may include a first cylindrical base portion, a cap, and a lip formed by a portion of the cap that extends horizontally outward beyond the first cylindrical base portion. The cap and lip may be formed such that a vertical distance exists between the lip and the semiconductor wafer, defining an intrusion area. The method may include removing excess portions of the first photoresist layer, including portions residing in the intrusion area, to isolate the bump.

Dependencies are inferred from the claim text.