Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

FIG. 1 illustrates a cross-sectional view of a package in accordance with some embodiments;

FIG. 2 illustrates the top view of a package and openings in a top dielectric layer of the package in accordance with some embodiments, wherein corner openings are elongated connectors;

FIG. 3 illustrates the top view of a package and openings in a top dielectric layer of the package in accordance with some embodiments, wherein a plurality of elongated openings is distributed to each corner;

FIG. 4 illustrates the top view of a package and non-solder openings of the package in accordance with some embodiments, wherein elongated openings and non-elongated openings are distributed depending on their distances to a neutral-stress point of the package;

FIG. 5 illustrates a top view of a package and openings in a top dielectric layer of the package in accordance with some embodiments, wherein inner openings adjacent to the corners of an underlying device die are elongated;

FIG. 6 illustrates the top view of a package and openings in a top dielectric layer of the package in accordance with some embodiments, wherein inner openings adjacent to the corners of an underlying device die group are elongated;